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Thymocytes express multiple different surface antigens according to their stage of maturation. We studied lymphocyte surface differentiation antigens using direct immunofluorescence technique in the thymus of 20 patients with myasthenia gravis (MG) and 10 controls undergoing cardiac surgery. Fluorescein isothiocyanate-conjugated monoclonal antibodies were used to stain thymic cell surface antigens. We found a decrease in the percent expression of CD1, CD5, and CD7 surface antigens and a significant increase of CD20+ cells in myasthenic thymus compared with the controls. The changes in the percent expression of CD3, CD4, and CD8 antigens were not significant. These data suggest both the decrease in the immunophenotypes corresponding to cortical thymocytes (probably reflecting the cortical atrophy of the MG thymus) and the increase of mature B Cells (CD20+), which may participate in an active immune response.

Thymocytes express multiple, different surface antigens according to their stage of maturation. Surface differentiation antigens have been studied with the technique of simultaneous dual-color, direct immunofluorescence in the thymuses of 20 patients with myasthenia gravis (MG) and 10 control subjects with cardiac diseases. Fluorescein isothiocyanate-conjugated and phycoerythrin-conjugated monoclonal antibodies were used to stain thymic cell suspensions. A significant decrease in the percentage of immature and common thymocyte phenotypes (CD1+,3+ and CD4+,8+) and a significant increase in the percentage of mature thymocyte phenotypes (CD1-,3+; CD4+,8-; and CD4-,8+) and of B cells (CD20+) were found in MG thymuses compared with controls. These data, indicating an increased availability of mature, fully immunocompetent T and B cells, indirectly suggest the occurrence of an active immune response in MG thymus.

The association of primary sclerosing cholangitis and renal disease is not frequent, and is limited to a few reported cases of immune complex glomerulonephritis. We report the case of a 34-year-old patient with sclerosing cholangitis diagnosed 5 years earlier, with well preserved liver function and no clinical manifestations of cholestasis, who developed minimal change nephropathy. During the nephrotic phase of the disease, the peripheral blood lymphocyte count was normal, with a relative increase in percent CD4+ and an increase in the CD4+: CD8+ ratio. CD4+ cells showed immunoactivation. The HLA-DR expression on T-cells was 59%, and 16.5% of CD3+ cells were CD25+. A course of prednisone therapy induced long-lasting remission of the nephrotic syndrome. Peripheral blood lymphocyte count and subtyping were normal 7 months after prednisone withdrawal. We conclude that primary sclerosing cholangitis can be associated with minimal change nephropathy; underlying cell-mediated immunity may be the common pathogenic mechanism.

Immunological disturbances with impairment of immune function and a higher incidence of lymphoproliferative disorders and other malignancies have been described in liver cirrhosis patients. To investigate the pathogenetic mechanism(s) involved in such associated we looked for a possible imbalance in peripheral blood T-lymphocyte subpopulations in patients with liver cirrhosis of differing severity. Immunophenotyping and counts of peripheral blood T-lymphocyte subpopulations were carried out using monoclonal antibodies conjugated with different fluorochromes in 31 consecutive cirrhotic patients and 23 matched healthy volunteers. Univariate and multivariate analyses of lymphocyte phenotype counts were performed and odds ratios were computed. Statistically significant associations, according to both univariate and multivariate analyses, were found between case/control status and mean CD3 and CD4 T-lymphocyte counts (P0.0001). A strong correlation was found between the Pugh's index and CD3 and CD4 lymphocyte counts, with a clear reduction of these phenotypes with increasing liver cirrhosis. Median CD3 and CD4 values were 2,283 and 1,329/microliters respectively among controls and 896, 801, and 492/microliters and 515, 514, and 307/microliters, respectively in categories A, B, and C of Pugh's classification. Very high odds ratios were found using the median values of CD3 and CD4 as a threshold. There was a statistically significant decrease for each of the T-cell phenotypes studied (CD2, CD3, CD4, CD8, CD16, CD19, CD20, CD56, CD57) between patients and controls (P0.0001). The progressive and severity-related decrease in mean peripheral blood CD3 and CD4 counts in liver cirrhosis suggests a progressive impairment of protective immune function and may be a factor facilitating malignancy in cirrhotic patients.

The homeostasis established by the interaction among the central nervous system, the immune system and the endocrine system, is radically altered by prolonged comatose state following severe head trauma. This must be taken into account when deciding on therapy and rehabilitation. In a group of post-comatose patients, we studied peripheral lymphocyte subpopulations, defined by monoclonal antibodies, and delayed hypersensitivity. Our findings are indicative of an immunological impairment originating at glioneuronal level, following head trauma. Such a temporary immune deficiency may in turn affect the equilibrium between the reconstitution of the blood-brain barrier and neuronal repair activity.

The paper studies the distribution of circulating lymphocytic phenotypes in 20 cases of recurrent aphthous stomatitis. The statistical analysis of data, together with that found in 40 normal subjects, reveals the selective immunoactivation of cytotoxic T lymphocytes and NK cells similar to that found during the course of acute viral diseases. In etiopathogenetic terms, results should therefore be considered as a possible demonstration of the viropathic genesis of this disease.

The spleen is a peripheral lymphatic organ where lymphocytes stop for long time during their circulation. We studied the peripheral blood lymphocyte subsets both in 30 subjects splenectomized for trauma and in 30 healthy, non splenectomized, subjects. The phenotypical characterization of lymphocyte subpopulations was performed employing monoclonal antibodies by direct immunofluorescence assays with single and double labelling. Comparing the results, we put in evidence, in splenectomized patients, an increase in all the lymphocyte subsets but one (L. G.L. Leu7+). The CD8+ population showed the major increase according with its large representation in the splenic tissue. Splenectomy induces a change in lymphocyte recirculating pool because of the loss of an important anatomical site of migration. This reduction of lymphocyte recirculating capacity can be related to a decreased efficiency in immunocompetence. In fact, many Authors showed that splenectomy is associated with several anomalies of both humoral and cellular immune response. In contrast with this, our group of splenectomized patients doesn't reveal a greater incidence of infections. We conclude that splenectomy realizes a new anatomical situation where the reduction of lymphocyte recirculating capacity can be related to a decreased statistical efficiency in immunocompetence.

The authors evaluated the peroperative immunologic state of patients with colorectal tumors and controlled the postoperative incidence of infections. Twenty-one patients were studied, and delayed type hypersensitivity reactivity determined by the CMI multitest (Merieux) eight days before and eight days after surgery. A lymphocytogram was performed using monoclonal antibodies. A significant percentage of patients were anergic preoperatively. Immunologic analysis revealed lymphocytosis in the first postoperative period. The largest absolute quantitative increase was shown by NK CD16+ cells. It is possible that the results, obtained by dynamic monitoring of the main parameters of cellular immunity, will offer a new way for prognostic evaluation of surgical risk.

Total body irradiation (TBI) produces prolonged immunosuppression with rare side effects. We studied 12 thymectomized patients affected with chronic generalized severe myasthenia gravis. All patients had been totally or partially refractory to prolonged oral treatment with immunosuppressive drugs, and most had contraindications for these drugs. Low-dose (1.8- to 2.3-Gy total dose) TBI was administered in single, 0.1-Gy doses, two to three times per week. TBI was well tolerated and was associated with objective clinical improvement in six patients, lasting more than 2 years in five. In addition, TBI produced a long-lasting lymphopenia with a pronounced decrease of T CD4+ lymphocytes; T CD8+ lymphocytes were almost unchanged over the 2 years of the study. CD16+ and CD20+ lymphocytes, after an initial decrease, increased above baseline. TBI was also associated with decreased anti-AChR antibody titer. The decrease of lymphocyte count and of anti-AChR antibody titer was more pronounced in the patients who improved, suggesting that lymphopenia and immunosuppression may have contributed to clinical improvement.

The authors investigated and compared lymphocyte subsets natural killer in 33 newborns and in 33 healthy adults. From 5 ml of heparinized venous blood were separated mononuclear cells on density-gradient Ficoll-Hypaque. The vitality was determined with immunofluorescent method (orange acridine and ethiobromide). It was positive if resulted at least 95%. Lymphocyte phenotype was also examined after incubation with monoclonal antiserum Becton-Dickinson conjugated with FITC and PE for 45' at 4 degrees C. Two hundred cells were counted on each slide with fluorescent microscopy. Total number of T-lymphocyte (Leu-4) was increased in newborns; total B-cells (Leu-12) were similar in newborns and healthy adults; T-helper/T-suppressor (Leu-3a/Leu-2a) ratio was above the normal range for increase T-helper. The percentage of subsets with double marker Leu-2a+/Leu-3a+ was always about 15-20%. NK cells with phenotype HNK-1 (Leu-7) were a little number in newborns while the percentage of NK-cells-Leu-11a was similar among adults and newborns.

Thin viable slices of normal or pathological human tissues were incubated in vitro with bromodeoxyuridine (BrdU). Later, cryostatic sections and histological sections from the same samples embedded in paraffin were examined by an immunohistochemical method using a monoclonal antibody anti-bromodeoxyuridine (anti-BrdU-MAb): on both cryostatic and histological sections, the nuclei of the S-phase cells proved positive. The optimization of the technique depends on the concentration of bromodeoxyuridine in the culture medium (160 microM), the duration of incubation (not less than two h), the method of DNA denaturation (2N or 4N HCl) and the dilution of the anti-BrdU-MAb (1:50). In vitro, immunohistochemical application of the BrdU/anti-BrdU-MAb method permits a quantitative assessment of the proliferative activity of a tissue as well as the direct location of the actively replicating cells in histological sections.

Radioisotopic study of platelet kinetics can provide a preliminary orientation in the diagnosis of thrombocytopenia. A study of the platelet kinetics in thrombocytopenic and normal subjects using the Cr51 isologous platelet labelling technique and subsequent in vivo injection of the labelled platelets was conducted. The results obtained confirm the reliability and usefulness of the technique. The identification of the limitations involved and the recognition of their significance in processing data allows the hematologist and the general practitioner to allow the right amount of room for the study of platelet kinetics in the diagnosis of thrombocytopenia.

The report attempts to show why therapeutic success in the treatment of Hodgkin's disease levelled off at the start of the Eighties. The prospects of future treatment based on more accurate interpretation of clinical and histopathological data, further cytological and immunological research as well as improved therapeutic techniques more carefully adapted to the variety of prognoses are also discussed.