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Background: Rapid urease tests for Helicobacter pylori have a sensitivity of 80% to 90%. Therefore histologic examination of gastric biopsies is recommended as a "backup" diagnostic test in rapid urease test-negative patients. However, noninvasive tests (urea breath test, serology, whole blood antibody tests) may provide a more rapid diagnosis and be less expensive but offer similar accuracy., Methods: Sixty-seven patients (no prior treatment for H pylori, no proton pump inhibitors, antibiotics, or bismuth within 4 weeks) undergoing endoscopy for evaluation of dyspepsia symptoms and testing rapid urease test-negative by antral biopsy were enrolled. All had the following tests: gastric biopsies (2 antral, 1 fundus; H&E and Alcian Yellow stain) examined for gastritis and H pylori; (13)C-UBT; capillary blood for whole blood rapid antibody tests: FlexSure HP, QuickVue, AccuStat, and Stat-Simple Pylori; serum for FlexSure HP; HM-CAP enzyme-linked immunoassay. H pylori infection was diagnosed (reference standard) if chronic gastritis was present on histology and at least 2 of the 3 following tests were positive: urea breath test, H pylori organisms unequivocally demonstrated in biopsies on special stain, and/or enzyme-linked immunoassay. The test and treatment costs per patient were calculated., Results: Of 67 patients with a negative rapid urease test, 4 were positive for H pylori. None had active peptic ulcer disease. Histology only identified 1 patient with organisms visible on special stain. Using chronic active gastritis (neutrophilic and mononuclear infiltrate) as a diagnostic criterion for H pylori, 6 patients would have been judged positive. However, only 2 of these were truly positive by the reference standard (positive predictive value 33%). Negative predictive value for presence of organisms and chronic active gastritis was 95% and 97%, respectively. All of the noninvasive tests identified all 4 truly positive patients correctly. Urea breath test and FlexSure whole blood assay yielded a substantial number of false-positive results (positive predictive value 31% and 36%, respectively); positive predictive value for the other tests ranged from 50% to 80%. All tests except histology had a negative predictive value of 100%. Histology was the most costly test (p < 0. 001 compared with all other tests), followed by urea breath test and HM-CAP serology (p < 0.001 compared with all rapid antibody tests)., Conclusions: Whole blood or serum antibody testing is a rapid, accurate, and cost-effective means for establishing H pylori status in rapid urease test-negative patients. Whole blood or serology rapid antibody testing should substitute for histology when the patient has not been previously treated for H pylori.

Background: The major impediment to success in solid organ transplantation is chronic rejection (CR). The characteristic lesion of CR is transplant vascular sclerosis (TVS). Although the mechanism of TVS is thought to have an immunologic basis, in humans immunosuppression does not prevent or reverse it. One possible therapy to prevent TVS is induction of donor-specific tolerance. Bone marrow chimerism has been successful in inducing tolerance in acute and chronic rejection heart and kidney transplant models. The highly immunogenic small bowel (SB) allograft provides a rigorous test of the efficacy of this tolerance regimen. We examined whether induction of tolerance by bone marrow chimerism could prevent TVS in a model of Fisher 344 (F344) to Lewis (LEW) rat SB transplantation., Methods: Bone marrow chimeras (BMC) were created by transplantation of T-cell-depleted F344 bone marrow into irradiated LEW rats. Chimerism was assessed by flow cytometric method. F344 SB, heterotopically transplanted into the chimeras, was clinically and histologically assessed for CR. F344 SB grafts, transplanted into cyclosporine-A-treated LEW recipients, served as control grafts for CR., Results: Cyclosporine-A-treated LEW rats chronically rejected F344 SB grafts. By contrast, the BMC group demonstrated tolerance and had long-term SB graft survival (>120 days) without TVS. The BMC demonstrated immunocompetence by prompt rejection of third party ACI (RT1av1) SB allografts., Conclusions: Bone marrow chimerism prevents chronic graft failure secondary to TVS in a model of chronic SB rejection. TVS fails to develop when tolerance is established, suggesting that the mechanisms involved in TVS are, in part, immunologically mediated.

The majority of renal neoplasms can be distinguished on the basis of histologic examination alone; however, there are morphologic similarities between clear cell renal carcinoma and chromophobe cell carcinoma, as well as between the granular/eosinophilic variants of these tumors and renal oncocytoma. Only a limited number of histochemical markers are available to aid in the differential diagnosis of these neoplasms. Hale's colloidal iron usually yields strong, diffuse cytoplasmic staining of chromophobe cell carcinomas whereas clear cell carcinomas are generally negative; however, interpretation of this stain is not always straightforward. By immunohistochemistry, vimentin is detectable in most clear cell carcinomas and is absent from most chromophobe cell tumors and oncocytomas, but reliance on a single antibody can be misleading. In this report we examine the use of commercially available monoclonal antibodies to RCC and CD10 in the differential diagnosis of common renal tumors. Eighty-five percent of clear cell carcinomas (53 of 62) had detectable surface membrane staining for RCC, and 94% (58 of 62) were positive for CD10. Papillary carcinomas were likewise strongly positive for RCC and CD10 in nearly all cases (13 of 14 each). In contrast, all 19 chromophobe cell carcinomas examined were completely negative for surface membrane staining with both of these markers. Oncocytomas were also negative for RCC (0 of 9), but CD10 was detectable in some cases (3 of 9). These results suggest that the presence of surface membrane staining for RCC and CD10 may be used to confirm a diagnosis of suspected clear cell or papillary renal carcinoma. Chromophobe cell carcinomas should be negative for both markers. The absence of RCC staining may also be helpful in the diagnosis of renal oncocytoma.

Objective: The aim of this study was to compare the performance characteristics of one serum and four whole blood rapid antibody tests for Helicobacter pylori infection., Methods: A total of 97 outpatients referred for endoscopic evaluation of dyspepsia were included. Antral biopsies were obtained for histology and rapid urease test. Serum was tested with an enzyme-linked immunoassay (HM-CAP) and a rapid serology test (FlexSure HP). A commercially available 13C-urea breath test was performed. Capillary blood obtained by fingerstick was tested with FlexSure HP, QuickVue, Accustat, and StatSimple pylori tests. Sensitivity, specificity, and accuracy of each rapid test was calculated relative to a criterion standard of histological gastritis and at least two of the four following tests positive: identifiable organisms on specially stained slides, rapid urease test, urea breath test, or serum immunoassay., Results: A total of 30 patients (31%) were infected. The FlexSure HP Serum, and FlexSure HP, QuickVue, Accustat, and StatSimple pylori whole blood tests had sensitivities of 90%, 87%, 83%, 76%, and 90%; specificities of 94%, 90%, 96%, 96%, and 98%, and accuracies of 93%, 88%, 92%, 87%, and 96%, respectively. Sensitivities were not statistically different. StatSimple pylori was more specific than FlexSure HP whole blood (p<0.03), and more accurate than FlexSure whole blood (p<0.024) and Accustat (p< 0.01). Serum immunoassay was significantly more sensitive (97%) than FlexSure whole blood, QuickVue, and Accustat (p<0.01), but its specificity (95%) was not statistically different from the rapid tests., Conclusion: Rapid antibody testing provides an accurate diagnosis of H. pylori infection. In general, these tests are less sensitive than, but as specific as, standard serology.

Background: Hepatitis C-related liver failure is the leading indication for liver transplantation worldwide. Although histologic recurrence is identified in the majority of patients, the spectrum of allograft injury is wide. To date, most studies have focused on the contribution of immunosuppression and viral factors. We hypothesized that the allograft plays a significant role in determining timing and severity of hepatitis C virus (HCV) recurrence. The purpose of this analysis was to determine if genetic polymorphisms of the tumor necrosis factor (TNF) locus were associated with the highly variable severity of HCV recurrence., Methods: Thirty-one HCV-seropositive liver transplant recipients with long-term follow-up were studied. Genomic DNA was extracted from archived donor spleens which corresponded to each patient. We performed polymerase chain reaction amplification, followed by sequencing for two promoter TNF-alpha variants (at positions -238 and -308), and restriction fragment length analysis for four polymorphic loci within the TNF-beta gene (NcoI, TNFc, aa13, and aa26)., Results: The relative prevalence of polymorphisms corresponded to distributions previously reported in normal control populations. Twenty-two of 31 (71%) patients received a donor liver homozygous for the wild type allele (TNF1) at the -308 TNF-alpha promoter region. The interval to histologic recurrence was significantly shorter and severity of HCV allograft hepatitis was significantly greater in patients with one or two TNF308.2 alleles. At last follow-up biopsy, 5 of 9 (56%) patients with a TNF308.2 donor liver had evidence of severe histological activity index as compared to 2 of 22 (9%) of patients receiving a donor liver homozygous for the TNF1 allele (P = 0.01). There was no correlation between rejection rates and the presence of any TNF-alpha or TNF-beta alleles. TNF-beta polymorphisms within the donor liver did not correlate with severity of HCV recurrence., Conclusions: The donor TNF-alpha promoter genotype may influence the inflammatory response to HCV reinfection of the graft and contribute to accelerated graft injury. If the association between this genetic marker (TNF308.2) and disease progression is confirmed, it could improve our understanding of HCV pathogenesis and influence donor selection and patient management.

Background: Radiofrequency (RF) ablation has been reported as a means of liver tumor destruction. This study evaluates the use of ultrasound monitoring of radiofrequency lesion creation and describes the morphology, histologic characteristics, and vascular effects of radiofrequency ablations in a pig liver model., Materials and Methods: Hemodynamic monitoring was established and laparotomies were performed in 50-kg pigs. Under ultrasound guidance, radiofrequency needle probes were placed in the liver at predetermined locations. Radiofrequency energy was applied over 15 min to generate lesions 3 cm in diameter. Eighty lesions were generated in 10 animals. At the completion of the experiment, the lesions were examined with ultrasound and then excised for CT, gross, and histologic examination., Results: There were no adverse systemic effects. Ultrasound imaging demonstrated the size, shape, and position of the lesions. Gross examination demonstrated a core of ablated tissue with a surrounding 1- to 2-mm hemorrhagic perimeter. Lesion volumes averaged 12.8 cc(3) (range 5-34 cc(3)). Final lesion shape and size were frequently altered by the cooling effect of local blood flow. Histologic stains demonstrated microvascular thrombosis and coagulative necrosis within the lesions. There appeared to be 100% cellular destruction within the lesion by cytochemical staining., Conclusions: We demonstrated that RF ablation is capable of killing large volumes of normal liver tissue; however, local vasculature plays a significant a role in defining the ultimate size and shape of the lesion created. This may interfere with the utility of radiofrequency ablation as a modality for local tumor control., (Copyright 1999 Academic Press.)

Background & Aims: After liver transplantation for hepatitis C virus (HCV), reinfection of the allograft invariably occurs. Indirect evidence suggests that the cellular immune response may play a central role. The purpose of this analysis was to determine the correlation between HCV-specific peripheral CD4(+) T-cell responses and the severity of recurrence after liver transplantation., Methods: Fifty-eight HCV-seropositive patients, including 43 liver transplant recipients with at least 1 year of histological follow-up, were studied. Peripheral blood mononuclear cells (PBMCs) were isolated from fresh heparinized blood and stimulated with either recombinant HCV antigens (core, E2, NS3, NS4, and NS5) or control antigens., Results: Fourteen (40%) of 35 patients with mild or no evidence of histological recurrence within their allografts responded to at least 1 of the HCV antigens. Eleven responded to NS3, 5 to all the nonstructural antigens, and 3 to the HCV core polypeptide alone. In contrast, in the 8 patients with severe HCV recurrence, no proliferation in response to any of the HCV antigens was seen (P = 0. 03) despite responses to the control antigens., Conclusions: Despite immunosuppression, HCV-specific, major histocompatibility complex class II- restricted CD4(+) T-cell responses are detectable in patients with minimal histological recurrence after liver transplantation. In contrast, PBMCs from patients with severe HCV recurrence, despite being able to proliferate in response to non-HCV antigens, fail to respond to the HCV antigens. These findings suggest that the inability to generate virus-specific T-cell responses plays a contributory role in the pathogenesis of HCV-related graft injury after liver transplantation. It is hoped that further characterization of the immunoregulatory mechanisms related to recurrent HCV will provide the rationale for novel therapeutic strategies and diminish the incidence of inevitable graft loss.

Purpose: To evaluate a new 19-gauge blunt-tipped, side-cutting, single throw transjugular biopsy needle for transvenous kidney biopsies., Materials and Methods: Transjugular transvenous kidney biopsies were performed with a modified 70-cm biopsy needle utilizing fluoroscopic guidance in nine swine. Three tissue specimens were obtained with four biopsy device passes in five animals and three biopsy device passes in four animals. Renal arteriography and venography were performed immediately before and after renal biopsy. Five animals were killed immediately after biopsy. Four animals were allowed to recover and underwent arteriography and venography prior to being killed, which varied from 1 to 6 weeks. Gross and histologic examinations of the biopsied kidney were performed after euthanasia. A pathologist reviewed all biopsy specimens for quality based on the number of glomeruli present., Results: Results of immediate and delayed arteriography and venography were normal in all cases. Histologic evaluation of all biopsy specimens demonstrated a range of two to 13 glomeruli per sample (mean, 6.5), with successful acquisition of the cortex. In one animal killed immediately after biopsy, a small subcapsular hematoma was present., Conclusion: The 19-gauge, side-cut biopsy needle with a blunt-tip stylet proved to be efficacious for obtaining renal cortical samples in right swine kidneys via a transjugular approach.

Background: The major impediment to long-term success in solid organ transplantation is the development of chronic rejection (CR). The vascular lesion of CR, transplant vascular sclerosis (TVS) is characterized by neointimal smooth muscle cell proliferation, and is driven by both immune- and nonimmune-mediated mechanisms. Although the features of chronic heart and kidney allograft rejection have been well characterized, the more immunogenic small bowel allograft has not received similar study., Methods: F344 small bowel (SB) was transplanted heterotopically into Lewis recipients that were treated with low-dose Cyclosporine A for 15 days. Lewis recipients of F344 or Lewis SB grafts without immunosuppression, served as controls. Grafts were assessed histologically when recipients showed clinical signs of rejection or at predetermined time points. The immunological components involved in the chronic rejection process were evaluated by immunohistochemical staining., Results: All SB allografts (100%) developed histologic evidence of CR Cyclosporine A. TVS was seen in 36 of the 46 (78%) of these allografts. The median time to develop TVS was 45 days. Immunohistochemical staining of chronically rejected grafts showed infiltration predominantly by CD4+ cells and macrophages, uniform up-regulation of class II MHC molecule expression, moderate to intense ICAM-1 staining in grafts harvested at postoperative day 45, and uniform neointimal cell staining for smooth muscle cell alpha-actin in the TVS lesions., Conclusions: This F344 to Lewis SB transplant model is a useful model that reproduces significant features of CR. The highly immunogenic nature of the SB allografts allows this model to serve as a stringent test for protocols designed to prevent CR.

Objective: To report a case of fulminant hepatic failure associated with the use of bromfenac, a new analog of the phenyl acetate class of nonsteroidal antiinflammatory drugs., Case Summary: A 60-year-old white woman with liver failure who had no known history of chronic liver disease was transferred to the liver transplant unit for evaluation. For three months preceding her illness, the patient was treated with bromfenac 25 mg po qid for arthritic pain. Prior to the initiation of bromfenac, her liver function test results were normal. Etiologic evaluation at presentation was unremarkable. The patient's condition continued to deteriorate, with the development of hepatic encephalopathy and worsening liver function test results while awaiting liver transplantation. Progressive hepatic and renal dysfunction along with respiratory decompensation ensued, and the patient died 48 days after initial presentation., Conclusions: Fulminant hepatic failure associated with the prolonged use of bromfenac appears to be an idiosyncratic response consistent with experience with other agents of its class. This case along with other cases of serious hepatotoxicity associated with the use of this agent ultimately resulted in bromfenac's removal from the market.

Renal cell carcinomas in children and young adults are rare, and the pathologic features of these tumors have not been well described. We reviewed 24 renal cell carcinomas in children and young adults ages 6 to 29 years, 14 of whom were younger than 18 years of age. Fourteen were female. In 19 (79%) of 24 cases, the tumor met histologic criteria for papillary renal cell carcinoma, with at least 50% papillary architecture. Four of the remaining five cases were typical clear cell tumors in patients known to have von Hippel Lindau syndrome, and one case was of chromophobe type. In the papillary tumors, calcifications, high nuclear grade, extracapsular extension (American Joint Commission on Cancer stage T3), and lymph node metastases were common. Among these papillary tumors, four distinct histologic patterns could be identified. Collecting duct-like tumors (two cases) involved the large collecting ducts, were multifocal and predominantly papillary, and had focal tubular and solid areas. These tumors were reactive for epithelial membrane antigen (EMA) and keratins, including CK7, but negative for Ulex europeaus and high molecular weight keratin 34BE12. Voluminous cell tumors (four cases) were composed of cells with extremely voluminous clear cytoplasm and, although predominantly papillary, had areas that also resembled clear cell tumors. These tumors were reactive for keratins AE1/AE3 but were otherwise negative for all other keratins, EMA, and U. europeaus. One of these tumors showed an X;7 translocation. Adult type tumors (12 cases) resembled papillary tumors of adults. These tumors were reactive for EMA and keratins, including CK7, and all but one were negative for U. europeaus and keratin 34BE12. This last case had trisomies of chromosomes 7, 16, 17, and 20. The final neuroendocrinelike case was multifocal, organoid, and composed of nests of small cells in a neuroendocrinelike pattern. Three of 13 patients were alive with disease at last follow-up, and three additional patients died of disease, all within 2 years. Progression was highly associated with lymph node involvement at the time of resection. We conclude that the clinicopathologic features of renal cell carcinomas in children and young adults differ from those arising in older adults. These tumors are characteristically high-grade, high-stage, papillary tumors with numerous calcifications, and several subtypes can be identified based on histologic, immunohistochemical, and cytogenetic features. Some subtypes appear to be unique to this age group.

Epithelial cells are known to be a major target for human cytomegalovirus (HCMV) infection; however, the analysis of virus-cell interactions has been difficult to approach due to the lack of in vitro models. In this study, we established a polarized epithelial cell model using a colon epithelial cell-derived cell line (Caco-2) that is susceptible to HCMV infection at early stages of cellular differentiation. Infection of polarized cells was restricted to the basolateral surface whereas virus was released apically, which was consistent with the apical and not basolateral surface localization of two essential viral glycoproteins, gB and gH. HCMV infection resulted in the development of a cytopathology characteristic of HCMV infection of colon epithelium in vivo, and infection did not spread from cell to cell. The inability of HCMV to infect Caco-2 cells at late stages of differentiation was due to a restriction at the level of viral entry and was consistent with the sequestration of a cellular receptor for HCMV. These observations provide the first evidence that restriction of HCMV replication in epithelial cells is due to a receptor-mediated phenomenon.

The expression of transforming growth factor-beta (TGF-beta) correlates with the incidence of renal glomerular and interstitial injury, however, nothing is known of the effect of these proteins on renal hemodynamics. This study examines the renal hemodynamic and morphologic effects of recombinant human TGF-beta2 in normal male Sprague Dawley rats. Acute infusion of TGF-beta (1.2 microg/kg per min) induced no hemodynamic changes, except for a modest though significant fall in mean arterial pressure. Administering TGF-beta2 at varying doses (20, 100, and 400 microg/kg) for 9 wk caused modest increases in systolic BP and proteinuria and minimal tubular interstitial fibrosis, however, renal hemodynamic end points were not significantly altered. TGF-beta2 (800 microg/kg) was also administered to volume-depleted rats for 7 consecutive days. In contrast to the findings in volume-replete animals, administration of TGF-beta2 to volume-depleted rats caused a marked reduction in GFR and medullary blood flow. Histologic fibrosis of the medullary vasa recta and cortical interstitium was seen, but glomeruli were unaffected. Thus, acute and short-term chronic TGF-beta2 administration did not induce major renal changes in the volume-replete state, however, TGF-beta2 combined with volume depletion caused medullary hypoperfusion and reduced GFR.

Background: Vancomycin-resistant Enterococcus (VRE) infection is emerging in the transplant population, and there is no effective antibiotic therapy available. The aims of this retrospective review were to (1) investigate the outcome of and (2) identify common characteristics associated with VRE infection and colonization in orthotopic liver transplant (OLTx) candidates., Methods: From October 1994 through September 1998, 126 isolates of VRE were identified in 42 of 234 OLTx recipients and 5 OLTx candidates who did not proceed to transplantation. Data were collected by patient chart review or from a computerized hospital database., Results: The 1-year mortality rate with VRE infection was 82%, and with VRE colonization, 7%. This mortality rate contrasts with a 14% 1-year mortality for non-VRE transplant patients (P <0.01, infected patients and colonized patients). Characteristics of VRE colonized and infected patients included recent prior vancomycin (87%), coinfection by other microbial pathogens (74%), recent prior susceptible enterococcal infection (72%), concurrent fungal infection (62%), additional post-OLTx laparotomies (47%), and renal failure (Cr >2.5 mg/dL or need for dialysis; 43%). Biliary complications were seen in 52% of post-OLTx VRE-infected or VRE-colonized patients (versus 22% in non-VRE transplant patients, P <0.05)., Conclusion: VRE infection is associated with a very high mortality rate after liver transplantation. The incidence of biliary complications prior to VRE isolation is very high in VRE-infected and VRE-colonized patients. The most common characteristics of VRE patients were recent prior vancomycin use, recent prior susceptible enterococcal infection, coinfection with other microbial pathogens, and concurrent fungal infection. With no proven effective antimicrobial therapy for VRE, stringent infection control measures, including strict and limited use of vancomycin, must be practiced.

Background: The envelope glycoprotein gB of human cytomegalovirus (CMV) occurs as one of four main genotypes. Some previous studies have proposed a relationship of CMV gB genotype to the frequency of symptomatic infection and to clinical outcomes in both transplant and human immunodeficiency virus-infected populations. Our aim was to define the distribution of CMV gB genotypes and the impact on acute cellular rejection and graft/patient survival after orthotopic liver transplantation (OLT)., Methods: Between October 1988 and December 1996, 325 patients underwent cyclosporine-based OLT at our center. CMV infection was surveyed prospectively and defined as viral isolation from blood or urine; 53 (16%) patients had detectable CMV. Isolates were genotyped by polymerase chain reaction amplification and restriction digest analysis., Results: The distribution of CMV genotypes was: gB1, 19 (36%) patients; gB2, 15 (28%) patients; gB3, 13 (24%) patients; and gB4, 4 (8%) patients. Two patients (4%) had mixed infection (1 + 3, 1 + 4). Age, preOLT diagnosis, use of ganciclovir prophylaxis, basal immunosuppression, mean number of HLA donor/recipient mismatches, and United Network of Organ Sharing status were comparable among patients with different genotypes. Patients with gBl had a significantly higher mean number of acute rejection episodes (1.52+0.30 vs. 0.67+0.22; P=0.027). However, there was no difference in rejection severity, including OKT3 usage or FK506 conversion, or development of chronic rejection among patients with different genotypes. The gB genotype did not affect the development of symptomatic or tissue-invasive CMV disease, detected in 15 patients. Actuarial rates of patient (odds ratio [OR] 3.0; confidence interval [CI] 1.49-6.0) and graft (OR 2.57; CI 1.25-5.22) survival were significantly diminished in the group with CMV infection versus those without CMV (P<0.0001 for both), but there was no association with CMV genotype., Conclusions: (1) Patients with CMV infection had significantly reduced patient and graft survival rates at 1 and 5 years after OLT as compared with OLT recipients without CMV infection. (2) CMV genotype gB1 was associated with a higher mean number of acute rejection episodes.

CD99, a marker for MIC-2, reacts with normal Sertoli cells and granulosa cells. We investigated CD99 expression in the development of normal ovary and testis as well as in 25 sex cord-stromal tumors (SCSTs), 7 epithelial neoplasms, and 6 germ cell tumors. Normal Sertoli cells and mature granulosa cells showed 3+ staining with CD99. Pregranulosa cells of primordial follicles were negative. All of the eight Sertoli-Leydig cell tumors were positive with antibody to CD99, with the well-differentiated tumors showing the greatest degree of staining intensity. Reactivity of 2+ to 3+ with CD99 was observed in all of the 11 granulosa cell tumors and in yolk sac components of the germ cell tumors investigated. All of the poorly differentiated carcinomas were negative with CD99. We concluded that CD99 might be a useful marker for SCSTs and that its degree of reactivity correlates with the degree of differentiation in Sertoli-Leydig cell tumors. Additionally, CD99 might aid in distinguishing granulosa cell tumors of the ovary from poorly differentiated carcinomas.

Background: The majority of patients infected with hepatitis C virus (HCV) undergoing liver transplantation develop evidence of histologic recurrence, and multiple mechanisms are likely poised to affect long-term allograft injury. The purpose of this analysis was to study the hypothesis that histologic and biochemical features at the onset of HCV recurrence predict the long-term evolution of allograft hepatitis., Methods: We studied 34 consecutive liver transplant recipients with evidence of histologic HCV recurrence and with a minimal histologic follow-up of 1 year (up to 6.2 years; mean: 696+/-83.2 days). Two-hundred and seventy-eight serial allograft biopsies (mean: 6.85+/-0.62 per patient, range: 4-21) were analyzed. The hepatic activity index was utilized to quantitate piecemeal necrosis, intralobular degeneration, portal inflammation, and hepatic fibrosis. The presence of hepatocyte ballooning degeneration and cholestasis was also assessed., Results: Although there was no significant difference with regard to initial hepatic activity index scores between patients who ultimately developed allograft cirrhosis (group 1; n=8) versus those with milder hepatitis (group 2; n=26), the finding of ballooning degeneration/cholestasis was more frequent in the former group (P=0.04). The distribution of HCV genotypes, the mean follow-up after orthotopic liver transplantation, the mean number of allograft biopsy specimens per patient, basal immunosuppression, and incidence of rejection were comparable in both groups. Patients who ultimately developed allograft cirrhosis had significantly higher initial total bilirubin at the onset of histologic recurrence and peak total bilirubin (pT. Bili, the highest value in the ensuing month). Actuarial rates of moderate-to-severe allograft hepatitis were significantly greater in patients with pT. Bili > or = 3.5 mg/dl (P=0.004). Multiple regression analysis identified pT. Bili as the only independent predictor of allograft cirrhosis., Conclusions: Features at the onset of histologic HCV recurrence predict the natural history of allograft injury; specifically, marked, transient hyperbilirubinemia is associated with the subsequent development of allograft cirrhosis.

Among patients with hepatic iron overload, the distinction between hereditary hemochromatosis (HH), a common yet treatable genetic disease, and other causes of siderosis remains problematic. The recent discovery of a specific homozygous mutation (C282Y) in a novel major histocompatibility complex class I-like gene (named HLA-H or HFE) in 80% to 100% of well-characterized cases of HH suggests that direct DNA-based mutation analysis may help resolve this dilemma. To assess the clinical utility of direct HLA-H mutation analysis in a typical diagnostic setting, we measured genotypic and phenotypic parameters of iron overload in 37 subjects with biopsy-proven hepatic siderosis (2+ or greater) and in 127 healthy control subjects. The prevalence of C282Y homozygotes was significantly greater in the hepatic siderosis group (32%) than in the control group (0%), confirming the association between this homozygous mutation and hepatic iron overload. In the hepatic siderosis group, C282Y homozygotes had significantly higher hepatic iron and ferritin levels, a significantly lower prevalence of hepatitis C virus or alcoholic liver disease, but no significant difference in the saturation of serum transferrin. Of the 20 subjects with a hepatic iron index (HII) in the previously defined "hemochromatosis range" (>1.9), 9 (45%) were C282Y homozygotes. Of the 11 nonhomozygous subjects with an HII greater than 1.9 (presumed false-positive HIIs), 10 (91%) had hepatic cirrhosis compared with 3 of 9 (33%) homozygotes with an HII greater than 1.9 who had cirrhosis (P<.02). The HII thus has poor diagnostic specificity for predicting genotypic HH in patients with cirrhosis. We conclude that direct determination of the HLA-H C282Y genotype may be the single best diagnostic test for HH, particularly in patients with cirrhosis, for whom the HII is quite nonspecific.

Fulminant hepatitis is a rare but potentially fatal adverse reaction that may occur after the use of disulfiram. A patient without a known history of liver disease was transplanted for fulminant hepatic failure secondary to disulfiram. A high index of suspicion and aggressive therapeutic approaches are essential for the prompt diagnosis and treatment of disulfiram-induced hepatic failure. The clinical presentation, histopathology, treatment, and all cases of disulfiram-induced hepatic failure reported in the English literature are reviewed. The role of orthotopic liver transplantation in a case of disulfiram-induced hepatic failure is discussed.

Background: Biliary anastomotic complications remain a major cause of morbidity in liver transplant recipients, ranging between 10% and 50% in large clinical series. An end-to-end choledochocholedochostomy with or without T tube (CDCD EE with T tube and CDCD EE w/o T tube) and a Roux-en Y choledochojejunostomy have been standard methods for biliary drainage., Methods: The objectives of this retrospective study were to: (1) evaluate the incidence of biliary tract complications using a new method of side-to-side choledochocholedochostomy without T tube (CDCD SS w/o T tube) and (2) compare the results of CDCD SS w/o T tube with those of CDCD EE with T tube and CDCD EE w/o T tube. From September 1991 through June 1996, 279 orthotopic liver transplants were performed in 268 patients and followed through December 1996 (minimum of 6 months' follow-up). A total of 227 CDCD anastomoses in 220 patients were studied (7 retransplants > 30 days): CDCD EE with T tube (n=124), CDCD EE w/o T tube (n=44), and CDCD SS w/o T tube (n=59)., Results: Sixty-nine biliary complications were observed in 220 patients (30%). Anastomotic and/or T-tube leaks were seen in 43 patients (19%), and anastomotic strictures were found in 26 patients (12%). Forty patients (18%) required percutaneous or endoscopic stent placement (6%) or surgical interventions (12%). CDCD EE with T tube had the highest incidence of biliary leak requiring rehospitalization but the lowest anastomotic stricture and intervention rate and the lowest 6-month mortality rate., Conclusions: CDCD EE with T tube was superior to CDCD EE or CDCD SS w/o T tube despite the increased number of rehospitalizations. CDCD SS w/o T tube did not offer significant advantages over conventional biliary anastomotic techniques.

Papillary renal cell carcinomas (RCCs) traditionally have been defined histologically as tumors with at least 50% true papillae. However, these tumors also have characteristic immunohistochemical and genetic features that separate them from other RCCs. We identified six tumors composed of solid sheets of cells without true papillae but that otherwise resembled papillary RCCs, which we feel represent solid variants of papillary RCCs. All six tumors were primary lesions of the kidney, all were strongly reactive for epithelial membrane antigen, cytokeratin 7, and callus keratin, and all were negative for the high molecular weight keratin antibody 34BE12. Four of four tumors tested showed trisomies for chromosome 7, chromosome 17, or both by either cytogenetic analysis or fluorescence in situ hybridization. Four cases were composed of solid sheets of cells containing distinct micronodules that in some cases resembled abortive papillae. The cells composing the micronodules had abundant eosinophilic cytoplasm, open chromatin, and in some cases prominent nucleoli. The intervening cells had similar nuclei, but the amount of cytoplasm was variable. In three of these micronodular cases, multiple tumors diffusely replaced the kidney; in the fourth case two typical clear cell RCCs and a typical papillary RCC were also present in the same kidney, but the micronodular tumor was unifocal. The two remaining cases were solitary tumors consisting of solid sheets of cells forming ill-defined tubules. These cells had scant clear cytoplasm and small round to elongate nuclei with occasional nuclear grooves but only rare small nucleoli. Limited follow-up has shown no evidence of disease in any patient thus far. The differential diagnosis includes "renal adenoma," renal adenomatosis, metanephric adenoma, and clear/granular cell RCC. We conclude that solid variants of papillary RCCs lack true papillae but have characteristic histologic, immunohistochemical, and genetic features.

Background: Despite recent advances in diagnosis and treatment, cytomegalovirus (CMV) infection continues to be a common cause of morbidity in liver transplant (LT) recipients. Because CMV infection suppresses cell-mediated immunity, which seems to be important in neutralizing hepatitis C virus (HCV) infection, we assessed the impact of CMV infection on histopathological HCV recurrence after LT., Methods: The study group was comprised of 43 consecutive LT recipients with at least 6 months of histologic follow-up. Group 1 consisted of the 8 patients who developed CMV viremia after LT; group 2 comprised the 35 patients without CMV viremia. There was no significant difference with regard to age, initial immunosuppression, incidence of rejection, distribution of HCV genotypes, or mean follow-up between the groups. Semiquantitative histopathologic assessment of allograft hepatitis was performed using the Knodell's score., Results: The mean total Knodell score of the final allograft biopsy was significantly greater in group 1 patients (P=0.016), with most of the difference due to periportal/bridging necrosis (P=0.009) and lobular activity subitem (P=0.01) scores. Half of the CMV viremic patients eventually developed allograft cirrhosis as compared with 11% of the CMV-negative patients (P=0.027). Accordingly, the cirrhosis-free actuarial survival by Kaplan-Meier estimates was significantly diminished in the CMV viremic patients. Glycoprotein B genotype analysis of CMV isolates revealed no significant differences between patients who did and those who did not develop allograft cirrhosis., Conclusions: After LT for chronic HCV, patients who develop CMV viremia incur a significantly greater risk of severe HCV recurrence.

Unclassified sex cord-stromal tumors (SCSTs) of the testis comprised predominantly of spindle cells can be difficult to classify. To achieve better definition of these tumors, we examined the histologic, histochemical, and ultrastructural features of four unclassified SCSTs with spindle-cell features, and compared their immunohistochemical features with those of 24 other SCSTs of the testis and ovary. Three of the spindle-cell tumors were composed of relatively short spindled cells with prominent nuclear grooves and intermixed epithelioid cells. All of the three were located adjacent to the rete testis. The fourth case consisted of elongate spindle cells that were reminiscent of smooth muscle. In all of the four cases, reticulin enveloped aggregates of cells of various sizes but not individual cells. Ultrastructural analysis of two of the spindle-cell tumors revealed desmosomes, numerous thin filaments, and focal dense-bodies. Immunohistochemically, all of the four tumors were reactive for S-100 protein and smooth muscle actin. Staining for S-100 protein and smooth muscle actin was also observed in three of six granulosa cell tumors and both juvenile granulosa cell tumors. Although variable staining for S-100 protein was found in 5 of the 12 other SCSTs (4 Leydig cell, 6 Sertoli-Leydig cell, and 2 unclassifiable ovarian SCSTs), reactivity for smooth muscle actin was present in only 1 Sertoli-Leydig cell tumor. In contrast, all of the four ovarian fibromas/thecomas were reactive for smooth muscle actin but failed to stain for S-100 protein. Taken together, the histologic, histochemical, immunohistochemical, and ultrastructural features of the spindle-cell tumors are similar to those of granulosa cell tumors. Reactivity for S-100 protein and smooth muscle actin is characteristic of these tumors. These tumors should be distinguished from other unclassified SCSTs.

During metastasis, tumor cells adhere to vascular endothelia. E-selectin is an adhesive protein expressed by cytokine-activated endothelium that can support adhesion of colon cancer cells through the recognition of specific carbohydrate ligands. Using a series of colon carcinoma cell lines that displayed E-selectin adhesiveness and an increased metastatic capacity in cytokine-treated mice, we examined possible inhibition of cytokine-dependent experimental lung metastasis by a soluble form of E-selectin, the recombinant fusion protein E-selectin-immunoglobulin. We found that E-selectin-immunoglobulin bound to the surfaces of HT-29 colon carcinoma cells and blocked the formation of cytokine-inducible experimental lung metastases; control L-selectin-immunoglobulin also bound to HT-29 cells but had no effect on tumor cell lung colonization. E-selectin-immunoglobulin was found to interfere with E-selectin-dependent adhesion of HT-29 cells to activated vascular endothelium and to block the retention of these cells in the lung, a process that implies tumor cell adhesive interactions with the host vasculature. Our results demonstrate that E-selectin-immunoglobulin inhibits adhesion and formation of lung metastases by colon carcinoma cells and suggest that impairment of tumor cell-endothelium adhesion might represent a therapeutic approach to the metastatic diffusion of tumors.

For more than two decades, papillary renal cell carcinoma has been recognized as a possible distinct clinicopathologic subtype of renal cell carcinoma (RCC). However, the histologic criteria for its diagnosis and the clinical outcome are still debated. In an attempt to clarify the diagnostic criteria and resolve issues pertaining to biologic potential, we have evaluated the histologic spectrum of 62 papillary RCCs and assessed significance of conventional pathologic prognostic parameters (Fuhrrman's nuclear grade [NG], pathologic stage [Robson and TNM], tumor size, multifocality, necrosis, and foam cells) and correlated these with outcome. The mean age of patients was 61.8 years (range 22-83), and males were more commonly affected (1.8:1). Grossly, most tumors were well circumscribed, averaged 6.7 cm in size (range 1.8-18), and were predominantly localized to the renal poles (polar vs. mid-renal, 3:1). Multifocality was a prominent feature (24 cases), and in three cases tumors were bilateral. Microscopically, papillary RCCs were predominantly papillary or tubulopapillary, often with a thick fibrous capsule, foam cells, necrosis, hemorrhage, and multifocality. Thirty-five percent of these tumors were low grade (NG I and II) and 65% high grade (NG III and IV). Sixteen of these tumors presented in a higher stage (stages III and IV), and the overall stage correlated with NG (chi 2, p = 0.009). Tumors were further distinguished by cytoplasmic features: eosinophilic (42%), basophilic (34%) and mixed (24%). Eosinophilic tumors were predominantly high grade, and basophilic tumors low grade (chi 2, p = 0.000). A mean follow-up of 57 months showed progression (metastasis, recurrence, or death due to disease) in 21%, whereas 63% were free of disease. Eleven percent died of unrelated causes, and 5% were lost to follow-up. Kaplan-Meier survival analysis showed that both high NG and stage were strongly associated with decreased survival (p = 0.0000 each), as were decreased foam cell (p = 0.0025) and vascular invasion (p = 0.0002). Comparison of 196 reported cases of papillary RCC, including the current series, with reported large series of conventional RCC indicates that papillary RCC usually presents at an early stage, and stage I (Robson) papillary RCC has better 5 year survival rates (87%-100%) than does RCC of the same stage (65-75%). The overall 5 years survival rate for papillary carcinoma (82-90%) was also higher than that of conventional RCC (44-54%). In a Cox proportional hazard regression model, TNM stage appeared to be the only significant variable (p = 0.0000, hazard ratio 10.1) in predicting outcome among papillary RCC. Based on this experience, we conclude that (a) papillary RCC is a malignant tumor, with a tendency to present at a lower stage, but with a distinct potential for progression and aggressive behavior; (b) stratification of these tumors according to cell type, amount of foam cells, presence or absence of vascular invasion, nuclear grade, and pathologic stage provides useful prognostic information; (c) the better 5-year survival rate of papillary RCC (overall and for stage I tumors) compared with that of conventional RCC suggests that it is a tumor with lower malignant potential. Thus, histologic subcategorization of a renal carcinoma as papillary RCC appears to have prognostic implications.

Alterations in the von Hippel-Lindau (VHL) gene are correlated with a diverse group of neoplasms including hemangioblastoma, clear cell renal carcinoma (RCC), and pheochromocytoma. Molecular genetic studies suggest that VHL is a tumor-suppressor gene; correspondingly, reintroduction of a VHL complementary DNA (cDNA) into RCC cells inhibits their ability to form tumors in nude mice. Recently, it was discovered that the VHL gene product (pVHL) binds to two subunits of the transcription elongation complex Elongin (SIII), resulting in decreased activity of this complex in vitro. It is proposed that pVHL functions in vivo as a negative regulator of transcription elongation; however, the intracellular localization of pVHL has not been clearly delineated. Epitope-tagged pVHL has been observed in either the nucleus or the cytoplasm of cultured cells, depending on the density of the cell culture. In this article, the cellular localization of pVHL in normal and neoplastic human tissues is documented using three different monoclonal antibodies. Strong expression of pVHL was observed in the epithelial cells of all organs examined, particularly in renal tubules, and was exclusively cytoplasmic. Lesser degrees of staining, also cytoplasmic, were observed in other cell types. A variety of carcinomas (lung, prostate, colon, breast, bladder, and thyroid) showed strong cytoplasmic staining for pVHL including four of five sporadic clear cell RCC. Of the nonepithelial neoplasms examined, only one tumor, an embryonal rhabdomyosarcoma, failed to stain for pVHL. The findings establish wide-spread expression of VHL at the protein level and provide strong evidence that most, if not all, pVHL is localized to the cytoplasm of cells in vivo.

Angiogenesis plays an important role in breast cancer growth and metastasis. Multiple adhesion molecules have been shown to perform critical functions in the process of angiogenesis. In this study, we analyzed 15 benign and 22 malignant estrogen-receptor-negative and estrogen-receptor-positive breast specimens for the presence of the endothelial cell adhesion molecules E-selectin and P-selectin. We found that E-selectin's expression was increased in the malignant breast tumors compared with their benign counterparts (23.86% of blood vessels versus 2.47%; P = 0.0005). Furthermore, E-selectin staining was found to be significantly increased in the estrogen-receptor-negative carcinomas compared with the estrogen-receptor-positive ones (P = 0.005). In vitro findings strongly correlated with the in vivo findings and showed a higher degree of E-selectin induction in endothelial cells exposed to conditioned media from estrogen-receptor-negative breast cancer cell lines than from estrogen-receptor-positive ones. The degree of E-selectin induction correlated with the amount of interleukin-1 alpha in the tumor-conditioned media. Neutralizing antibodies to interleukin-1 alpha significantly inhibited the E-selectin expression in endothelial cells exposed to tumor-conditioned media. The results indicate that the endothelial E-selectin expression during angiogenesis is related to breast carcinoma progression in vivo and that this component of angiogenesis may be due directly to tumor-cell-secreted interleukin-1 alpha.

Purpose: Creation of presinusoidal chronic portal venous hypertension by means of repeated portal vein (PV) embolization was explored in an attempt to improve a porcine model of transjugular intrahepatic portosystemic shunt (TIPS) patency., Materials and Methods: Six microswine underwent weekly PV embolization for 5 weeks with a total of 10.4-12.6 g of polyvinyl alcohol (PVA) particles (0.149-0.250 mm in size). Portography, liver function tests, pressure measurement in the PV and inferior vena cava (IVC) before and after PV embolization, and histopathologic evaluation of the livers were performed., Results: Transhepatic portal venography performed after each embolization demonstrated diffuse PV branch occlusion in all cases. At weekly follow-up, reconstitution of flow was demonstrated in these branches; permanent occlusion of PV branches was not achieved. The mean PV pressure elevated acutely from 17.3 mm Hg +/- 0.9 to 24.5 mm Hg +/- 4.2 (P < .01) after each embolization. However, the pressure always returned to baseline on the follow-up studies 1 week later. Liver function tests were normal. Histopathologic evaluation of the liver showed, in multiple PV branches, central plugs of PVA with peripheral recanalization. The liver parenchyma was otherwise normal., Conclusion: Massive embolizations of PV with PVA at weekly intervals failed to create permanent portal hypertension or induce hepatic fibrosis.

Stimulation of the erythropoietin receptor (EPO-R) or the interleukin-2 receptor (IL-2-R) by their respective ligands has been reported to activate tyrosine phosphorylation of the cytoplasmic protein, Shc. We have recently characterized a cell line, CTLL-EPO-R, that contains functional cell-surface receptors for both EPO and IL-2. Although stimulation with IL-2 or IL-15 resulted in the rapid, dose-dependent tyrosine phosphorylation of Shc, stimulation with EPO failed to activate Shc. EPO, IL-2, and IL-15 activated the tyrosine phosphorylation of the adaptor protein, Shp2, and the association of Shp2/Grb2/cytokine receptor complexes. In addition, EPO, IL-2, and IL-15 activated Raf1 and ERK2, demonstrating that the Raf1/MEK/MAP kinase pathway was activated. These results indicate that multiple biochemical pathways are capable of conferring a mitogenic signal in CTLL-EPO-R. EPO can activate the Raf1/MEK/MAP kinase pathway via Shc-dependent or Shc-independent pathways, and Shc activation is not required for EPO-dependent cell growth in CTLL-EPO-R.

Many mitogens and human oncogenes activate extracellular regulated kinases (ERKs), which in turn convey proliferation signals. ERKs or mitogen-activated protein (MAP) kinases are inactivated in vitro by MAP kinase phosphatases (MKPs). The gene encoding one of these MKPs, MKP-1, is a serum-inducible gene and is transcriptionally activated by mitogenic signals in cultured cells. As MKP-1 has been shown to block DNA synthesis by inhibiting ERKs when expressed at elevated levels in cultured cells, it has been suggested that it may act as a tumor suppressor. MKP-1 mRNA and MAP kinase (ERK-1 and -2) protein expression was assessed in 164 human epithelial tumors of diverse tissue origin by in situ hybridization and immunohistochemistry. MKP-1 was overexpressed in the early phases of prostate, colon, and bladder carcinogenesis, with progressive loss of expression with higher histological grade and in metastases. In contrast, breast carcinomas showed significant MKP-1 expression even when poorly differentiated or in late stages of the disease. MKP-1, ERK-1, and ERK-2 were co-expressed in most tumors examined. In a subset of 15 tumors, ERK-1 enzymatic activity as well as structural alterations that might be responsible for loss of function of MKP-1 during tumor progression, were examined. ERK-1 enzymatic activity was found to be elevated despite MKP-1 overexpression. No loss of 5q35-ter (containing the MKP-1 locus) was detected by polymerase chain reaction in metastases compared with primary tumors. Finally, no mutations were found in the catalytic domain of MKP-1. These data indicate that MKP-1 is an early marker for a wide range of human epithelial tumors and suggest that MKP-1 does not behave as a tumor suppressor in epithelial tumors.

Markers of cellular proliferation have proven to be useful prognostic markers in several tumor types. Recently, immunoreactivity for cyclins was found to provide an independent marker of tumor proliferation in breast cancer. In this study, we sought to determine the pattern of immunoreactivity for cyclins A, B, E, and Ki-67 in surgically resected prostate cancer and to determine their possible prognostic significance. Twenty-eight tumors of American Urological Association stages B and C were selected for study. Immunoreactivity for cyclins A and B was detected in most tumors and was present at significantly reduced levels as compared with breast cancer. Staining for cyclin E was present in four tumors and was present only in focal areas in two of the four. Such focal variation in expression of cell cycle regulators may reflect genetic instability in a tumor. Immunoreactivity for cyclins A and B was correlated with both Ki-67 index (the percentage of cells with Ki-67 immunoreactivity) and with each other. A Ki-67 index greater than 4.0 was associated with shorter time to prostate-specific antigen-detected relapse (P = 0.026). The fraction of cells staining for cyclins A and B divided by the fraction of cells staining for Ki-67 [(A+B)/K] was highly predictive of relapse, with values less than 0.50 associated with more rapid progression (P < 0.001). This latter result remained statistically significant after controlling for Gleason score by stratification. Our results suggest that immunoreactivity for markers of cellular proliferation may provide useful prognostic information in localized prostate cancer, and they need to be validated in a larger numbers of patients.

Purpose: A comparative histologic analysis of human and swine transjugular intrahepatic portosystemic shunts (TIPS) was performed to investigate factors limiting TIPS patency and to further develop an animal model for TIPS., Materials and Methods: Twenty-one human and 13 porcine shunts were evaluated by means of gross inspection, histologic evaluation, and electron microscopy., Results: Severe stenosis (> 75% narrowing) or occlusion was detected with portal venography in nine of the 21 human shunts (48%) and in 10 of 13 porcine shunts (77%). Gross or histologic evidence of a substantial biliary fistula was observed in seven of nine porcine shunts and in seven of eight human shunts with severe parenchymal tract stenosis or occlusion. No evidence of substantial bile duct injury was identified in the 13 human shunts or two swine shunts with patent, nonstenotic parenchymal tracts (P < .01, Fisher exact). Histologic findings in porcine shunts mimicked human tissue responses, including a metaplastic proliferation of bile duct epithelium at sites of bile duct transection., Conclusion: Bile duct transection and bile leak are significantly associated with TIPS parenchymal tract abnormalities in patients and swine. TIPS in swine created with the Wallstent faithfully reproduce gross morphologic and histologic changes observed in patients.

Although much has been learned about clinically localized PCa, no single prognostic parameter has been identified that is uniquely reliable in assessing prognosis. The best approach to the newly diagnosed PCa patient remains unchanged: to review all the clinical, radiologic, and histopathologic findings together. In combination, the serum PSA level and the histologic features of a tumor on biopsy can be used to predict the likelihood that a tumor is organ-confined or has spread beyond the gland. By this approach, some patients may be placed into a low-risk category for which "watchful waiting" may be a reasonable option. For other patients, the benefit from this approach is in making more informed decisions concerning definitive therapy and/or the use of adjuvant therapy. The role of the surgical pathologist is to provide as much information as possible regarding the amount, location, and differentiation of tumor present in biopsy and TUR specimens. Prognostic interpretation of these histopathologic findings depends on good communication between pathologists and urologists, oncologists, and radiation oncologists, which remains a cornerstone in therapeutic decision making.

E-selectin, an endothelial-cell-specific leukocyte adhesion molecule, may also function in angiogenesis. To investigate its role in a noninflammatory angiogenic disease, E-selectin was analyzed by immunohistochemistry in specimens of proliferative phase and involutive phase hemangiomas. Hemangioma is an endothelial cell tumor of capillary blood vessels that grows rapidly during infancy and regresses spontaneously during childhood. E-selectin expression was high in proliferative phase specimens and was co-localized with dividing microvascular endothelial cells. Relative to the number of blood vessels, E-selectin declined significantly in involutive phase specimens demonstrating that E-selectin correlates with angiogenesis in the tumors. E-selectin was not detected in quiescent endothelium but was co-localized in dividing microvascular endothelial cells in placenta and neonatal foreskin, two tissues with ongoing growth of microvessels. These in vivo studies support the hypothesis that E-selectin functions in angiogenesis and suggest that E-selectin may be a marker for proliferating endothelium.

Papillary renal cell carcinoma (papillary RCC) is an uncommon histologic variant of RCC with distinct gross, microscopic, and immunohistochemical features. Recent karyotypic analyses suggest that papillary RCC differs from other types of RCC at the genetic level as well. Whereas nonpapillary (clear cell, granular cell) RCC is characterized by deletions in chromosome 3p, papillary tumors reportedly exhibit a pattern of chromosomal trisomies, typically including chromosomes 7 and 17. To further examine the relationship between overrepresentation of these chromosomes and papillary histology, archival material from 36 papillary tumors was subjected to fluorescence in situ hybridization (FISH) analysis using alpha-satellite repeat probes specific to 7 and 17. Excess signals for chromosome 17 were detected in 22 of 28 (78%) low-grade papillary tumors (Fuhrman nuclear grades 1 and 2), and in seven of eight (87%) high-grade tumors (grades 3 and 4). Correlation of chromosome 17 FISH signals with karyotypes performed on two low-grade and three high-grade tumors was excellent. Among the cases without evidence of excess chromosome 17 were three unusual papillary tumors with sclerotic and hyalinized fibrovascular cores. In two cases, comparison was made of FISH signals from multiple, separate gross nodules of tumor; concordance for trisomic 17 signals was observed in one case, but not in the other. Chromosome 7 signals were overrepresented in all seven papillary tumors examined. DNA ploidy was determined in 19 of the 36 tumors; a relationship between DNA ploidy and polysomy 7 or 17 was not apparent. To examine the possible role of chromosome 3p deletions in the development of papillary RCC, 11 cases were studied for loss of heterozygosity (LOH) at one or more loci in the region of 3p13-21. Only three of the 11 cases had LOH at these loci. The findings are discussed with respect to the development and progression of papillary RCC.

We have constructed transgenic mice in which the mouse mammary tumor virus long terminal repeat controls the expression of murine monocyte chemoattractant protein-1 (MCP-1). Several independently derived lines of transgenic mice constitutively expressed MCP-1 protein in a variety of organs. Protein extracts from these organs had substantial in vitro monocyte chemoattractant activity that was neutralized by an anti-MCP-1 Ab, indicating that transgenic MCP-1 protein is biologically active. However, no transgenic mouse at any age displayed monocyte infiltrates in MCP-1-expressing organs. Two transgenic lines had circulating MCP-1 levels of 13 to 26 ng/ml, which is a concentration sufficient to induce maximal monocyte chemotaxis in vitro. These transgenic lines showed a 1 to 1.5 log greater sensitivity to infection with Listeria monocytogenes and Mycobacterium tuberculosis. A third transgenic line had lower serum levels of MCP-1 and was resistant to L. monocytogenes. The results suggest that this transgenic model is one of monocyte nonresponsiveness to locally produced MCP-1 due to either receptor desensitization or neutralization of a chemoattractant gradient by high systemic concentrations of MCP-1. Regardless of the mechanism, the data indicate that constitutively high levels of MCP-1 expression do not induce monocytic infiltrates, and that MCP-1 is involved in the host response to intracellular pathogens.

CD3+ peripheral blood T lymphocytes were evaluated for expression of vascular endothelial growth factor (VEGF), an endothelial cell mitogen and potent angiogenic factor. VEGF mRNA expression was confirmed in CD3+ cells and Jurkat cells, a human T-cell line, by reverse transcription-PCR and in CD4+ and CD8+ T cell subtypes by Northern blot hybridization. Steady-state levels of VEGF mRNA were inducible in CD3+ T cells by hypoxia, a known inducer of VEGF mRNA accumulation. Secreted VEGF was detected in CD4+ and CD8+ T cell- and Jurkat cell-conditioned medium, indicating that T lymphocytes are capable of exporting bioactive concentrations of VEGF into the extracellular space. Human prostate and bladder cancers (prostatic adenocarcinoma and transitional cell carcinomas) were evaluated for VEGF mRNA expression by in situ hybridization. Tumor-infiltrating lymphocytes (TIL), identifiable immunocytochemically as T cells, along with tumor cells in these cancers, expressed VEGF mRNA. TIL in bladder cancers could be labeled with a specific anti-VEGF mAb, indicating that TIL are likely to be able to secrete VEGF protein in situ at bioactive concentrations. The finding that peripheral T cells and TIL in human tumors synthesize a factor known to be a specific mediator of neovascularization suggests a role for T lymphocytes as cellular effectors of angiogenesis.

Papillary renal cell carcinoma (RCC) is an uncommon subtype of RCC that has distinctive gross, histologic, and cytogenetic features, but for which only limited immunohistochemistry data have been reported. We compared 36 papillary RCCs and five renal cell adenomas with 19 non-papillary (clear cell and granular) RCCs using a variety of antibodies to keratin and carcinoembryonic antigen (CEA). Papillary tumors were often multifocal and associated with coexistent adenomas, whereas nonpapillary tumors generally lacked these features. Low-grade papillary RCCs demonstrated three occasionally overlapping histologic patterns (typical, trabecular, and sclerotic), whereas high-grade tumors were characterized by an admixture of many patterns. Immunohistochemically, 100% (36 of 36 cases) of the papillary tumors were positive for AE1/AE3, and 92% (33 of 36 cases) were positive for callus keratins; only 3% (one of 36 cases) stained for 34BE12, and 11% (four of 36 cases) weakly stained for CEA. The five renal cell adenomas were likewise positive for AE1/AE3 (five of five cases) and callus (five of five cases) keratins. In contrast, 85% (16 of 19 cases) of the nonpapillary tumors stained for AE1/AE3, but only 5% (one of 19 cases) stained for callus; none (0/19) stained for 34BE12, and 10% (2/19) weakly stained for CEA. The consistent expression of callus keratins by papillary RCCs and renal cell adenomas underscores the close relation of these lesions, providing additional evidence for their oncological distinction from nonpapillary RCCs.

Objective: We describe our 3-year experience using spiral CT in the evaluation of small renal masses in order to determine the usefulness of this technique for classifying the lesions and to correlate specific CT features with pathologic findings., Materials and Methods: We retrospectively analyzed spiral CT scans and results of pathologic examinations of surgically extirpated small (< or = 3 cm) renal masses in 35 patients. The masses included 27 renal cell carcinomas, two transitional cell carcinomas, one leiomyoma, one angiomyolipoma, and four benign cysts. Several imaging features, including attenuation, pattern of contrast enhancement, presence and type of calcification, cyst wall, and septation, were correlated with pathologic findings., Results: Most renal cell carcinomas had a solid growth pattern (n = 19), had attenuation values on unenhanced scans of 20 H or greater (n = 26), and had attenuation values that increased by at least 10 H with contrast enhancement (n = 26). Only three renal cell carcinomas were mostly cystic on pathologic examination. Heterogeneous enhancement correlated with the presence of acellular regions (p = .02). Of 12 cystic masses, spiral CT showed the absence of a thick or nodular fibrous capsule in seven of nine masses (specificity, 0.78) and the absence of several (or nodular) septations in six of seven masses (specificity, 0.86) but was not as sensitive in detecting these features., Conclusion: Spiral CT can show many of the key imaging features of small renal masses used to distinguish between benign and malignant lesions. However, despite the theoretical benefits of volumetric CT, some lesions remain indeterminate and require surgical removal for diagnosis.

Monocyte chemoattractant protein-1 (MCP-1) is a member of the chemokine-beta (or C-C) family of cytokines. Murine MCP-1, first identified as the JE gene, differs from human MCP-1 in molecular size and extent of glycosylation. We have used Chinese hamster ovary cells to express recombinant murine MCP-1 and find that its predominant form is a microheterogeneous protein of M(r) approximately 25,000. Most of MCP-1's microheterogeneity is due to variable amounts of sialic acid that are terminally attached to a constant number of O-linked oligosaccharide chains per molecule. This carbohydrate, along with a small amount of N-linked carbohydrate, accounts for 50% of the apparent molecular size of murine MCP-1 and is not required for in vitro monocyte chemoattractant activity. Mutational analysis shows that most of the carbohydrate is added to a 49-amino acid C-terminal domain that is not present in human MCP-1 and is not required for in vitro biologic activity, suggesting that murine MCP-1 consists of an N-terminal domain containing monocyte chemoattractant activity and a heavily glycosylated C-terminal domain of as yet unknown function. MCP-1 produced in COS cells contains a small amount of sulfate, but Chinese hamster ovary-produced MCP-1 does not. The absence of sulfate does not alter MCP-1's in vitro chemoattractant properties. In vitro, highly purified murine MCP-1 attracts monocytes, but not neutrophils, with a specific activity similar to human MCP-1 (EC50 approximately 0.5 nM). Equilibrium binding experiments with human monocytes reveal the presence of approximately 3000 binding sites per cell with a Kd of 0.77 nM. In vivo, injection of up to 1 micrograms murine MCP-1 in a variety of murine strains induces the appearance of a sparse mixed inflammatory infiltrate. The disparity between MCP-1's in vitro and in vivo effects suggests that other factors may be required to elicit a full-blown monocyte chemotactic response to MCP-1 in vivo.

The carbohydrate structure sialyl-Lewis X (SLex) can function as a ligand for E-selectin, formerly known as endothelial leukocyte adhesion molecule-1 (ELAM-1). This study was performed to analyze the expression of SLex by leukocytes and other cell types in the context of inflammatory and immune processes. Human peripheral blood cells were examined by flow cytometry using monoclonal antibody CSLEX1 directed against SLex. Cell surface SLex was found in abundance on nearly all isolated polymorphonuclear leukocytes (PMN) and monocytes, and at low levels on a substantial portion (up to 40%) of natural killer cells. This moiety was expressed also on approximately 10% of peripheral blood T cells. Immunohistochemistry was performed on various human tissues involved in inflammatory or immune processes and on secondary lymphoid tissues. In acute appendicitis, endothelial cells of postcapillary venules expressed E-selectin, and most PMN, both within vessels and extravasated, expressed SLex. A substantial number of monocytes/macrophages in inflamed appendiceal, synovial, and dermal tissues also reacted with antibody CSLEX1; however, only rare tissue macrophages in uninflamed nonlymphoid sites showed expression of SLex. These observations are consistent with the concept that SLex on circulating PMN and monocytes functions as a ligand for endothelial E-selectin in the development of inflammatory reactions. SLex-positive lymphocytes also were seen, notably, T lymphocytes in inflamed skin. An unexpected finding was that the CSLEX1 antibody also reacted with venular endothelium in certain lymphoid tissues and in inflamed appendix, but not with endothelium in normal appendix. Whether the SLex antigen identified on endothelium represents de novo expression or passive adsorption remains to be determined.

Thrombospondin is an adhesive glycoprotein that is thought to play a role in tissue genesis and repair. We have used a monoclonal anti-thrombospondin antibody, designated 5G11, to localize thrombospondin in paraformaldehyde fixed, paraffin-embedded sections of developing mouse embryos. Thrombospondin expression is observed in uterine smooth muscle, endometrial glands, the decidua, and trophoblastic giant cells during the initial phase of post-implantation development in the embryo. Cardiac myocytes and neuroepithelial cells show positive staining for thrombospondin at day 8.5 of gestation, and this expression continues throughout the development of the myocardium and central nervous system. Strong staining for thrombospondin is seen in developing bone and in the liver. Thrombospondin is also observed in developing smooth muscle and skeletal muscle, as well as in a variety of epithelia, including the epidermis, small intestinal epithelium, lens epithelium, renal tubular epithelium, and the epithelium of the developing tooth. Comparison of thrombospondin staining with that of two known cell surface receptors for thrombospondin, syndecan and the vitronectin receptor, reveals remarkable colocalization of thrombospondin and syndecan in all tissues, but almost no coexpression with the vitronectin receptor. Coexpression of thrombospondin and syndecan may play an important role in cell-cell or cell-matrix interactions during development.

Inducible cell adhesion molecule 110 (INCAM-110), is a 110-kd adhesion receptor for lymphocytes and monocytes identified on cytokine-activated endothelium. Using immunoperoxidase techniques, little or no INCAM-110 was detected on endothelium in normal human tissues. In contrast, INCAM-110 was expressed in postcapillary venules in a variety of active inflammatory processes. In acute appendicitis, INCAM-110 was found coincident with strong expression of endothelial leukocyte adhesion molecule 1 (ELAM-1), a cytokine-inducible molecule that functions in neutrophil adhesion. However, in certain chronic inflammatory processes (eg, sarcoidosis), INCAM-110 was observed without simultaneous ELAM-1 expression. Anti-INCAM-110 antibody E1/6 also marked several extravascular cell types, including lymphoid dendritic cells, some tissue macrophages, synovial lining cells, and reactive mesothelial cells. These data suggest a role for endothelial INCAM-110 in the pathophysiology of both acute and chronic inflammatory reactions. Furthermore INCAM-110 may function as an adhesion molecule for mononuclear leukocytes in a variety of extravascular sites.

The pituitary hormones LH, FSH, and TSH are secreted as dimers of two subunits, alpha and beta. The alpha-subunit, identical in all three hormones, is produced by the pituitary in excess of beta and secreted as free subunit. Bovine free alpha does not combine with purified beta-subunit and contains an extra O-linked oligosaccharide not found on dimer alpha. We have developed an assay to quantitate this modified form of alpha in the medium of incubated steer pituitary slices. The assay, based on reverse phase HPLC analysis of radiolabeled alpha-subunit tryptic peptides, shows that under basal conditions, 75% of secreted free alpha is O-glycosylated. When the secretagogue LHRH is added to the slices, a 14-fold increase in LH dimer release is observed, but secretion of the modified alpha is increased by only 2-fold. Our results indicate that the majority of free alpha-subunit secreted by the pituitary contains O-linked oligosaccharide, and that secretion of this form of alpha differs from that of LH dimer.

A group of ompA mutants of Escherichia coli K12 are described which were sensitive to bacteriophage K3 in a background wild-type for lipopolysaccharide (LPS). With mutant LPS in vivo (lacking some core sugar residues), however, the ompA mutations gave resistance to K3. Outer membrane levels of OmpA protein were normal or near-normal when the mutations resided in either wild-type or mutant LPS backgrounds. Strains in which the mutations occurred in a wild-type LPS background adsorbed K3 phage at the same initial rate and to the same extent as a wild-type strain, but the efficiency of plaquing of the adsorbed K3 was reduced to 25-50% of wild-type levels. Under conditions where a wild-type strain irreversibly adsorbed over 90% of available phage K3 within 3 min, double mutants (ompA mutant, LPS mutant) left 90% of the phage viable after 1 h. The 10% of inactivated phage did not form plaques.

The glycoprotein hormones lutropin (LH) and chorionic gonadotropin (CG) share a common structure consisting of an identical alpha subunit noncovalently linked to a hormone-specific beta subunit. While LH is produced in the anterior pituitary, CG is synthesized in placenta. To compare the assembly, processing, and secretion of human LH and CG in the same cell type, we have expressed their subunits, individually and together, in mouse C-127 mammary tumor cells. Analysis of transfected clones revealed an unexpected difference in the secretion of individually expressed subunits. Whereas alpha and CG beta subunits were rapidly and quantitatively secreted, only 10% of newly synthesized LH beta subunit reached the medium. The remaining subunit was found in an intracellular, endoglycosidase H (endo H)-sensitive pool that had a turnover rate of approximately 8 h. Coexpression with alpha subunit resulted in "rescue" of LH beta subunit by formation of LH dimer, which was efficiently secreted. However, combination of LH beta with alpha was slow, with an overall efficiency of only 50% despite the presence of excess alpha. In contrast, CG beta was rapidly assembled with the alpha subunit after synthesis. The two beta subunits also differed in their influence on the N-linked oligosaccharide processing of combined alpha. The oligosaccharides of LH dimer were endo H resistant, while those of CG dimer remained partially endo H sensitive. Thus, despite a high degree of homology between LH beta and CG beta, the two subunits differ in their secretion as free subunits, their rate of assembly with alpha subunit, and in their effect on the N-linked oligosaccharide processing of combined alpha.

Human chorionic gonadotropin (hCG) is a member of a family of heterodimeric glycoprotein hormones that have a common alpha subunit but differ in their hormone-specific beta subunits. The beta subunit of hCG (hCG beta) is unique among the beta subunits in that it contains four mucin-like O-linked oligosaccharides attached to a carboxyl-terminal extension. To study the effects of O-glycosylation on the secretion and assembly of hCG, expression vectors containing either the hCG beta gene alone or together with the hCG alpha gene were transfected into a mutant Chinese hamster ovary cell line, IdID, which exhibits a reversible defect in O-glycosylation. Our results reveal that hCG beta can be secreted normally in the absence of its O-linked oligosaccharides. hCG beta devoid of O-linked carbohydrate can also combine efficiently with hCG alpha and be secreted as an intact dimer. We conclude that in Chinese hamster ovary cells, the hCG beta O-linked chains play no role in the assembly and secretion of hCG. The normal and O-linked oligosaccharide-deficient forms of hCG secreted by these cells should prove useful in examining the role of O-linked chains on the biological function of hCG.