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Objective: It remains unclear whether autoantibodies are useful biomarkers to tailor the choice of biological treatment in RA. We investigated the relationship between the presence and levels of different RF and ACPA isotypes and the response to TNF blockade in an exploratory study., Methods: A total of 101 active RA patients were prospectively treated with infliximab (3 mg/kg). Changes in disease activity were monitored by the 28-joint DAS (DAS-28). Serum levels of different isotypes [immunoglobulins M, G and A (IgM, IgG and IgA)] of RF and anti-citrullinated peptide antibodies were measured by ELISA., Results: The mean DAS-28 decreased from 5.9 (1.1) at baseline to 4.0 (1.3) at Week 16 of infliximab treatment (P < 0.001). High baseline levels of different isotypes of RF (all P < 0.008), ACPA IgM (P = 0.008) and ACPA IgG (P = 0.07) were associated with an absolute decrease in DAS-28 after TNF blockade. This relationship persisted after adjusting for DAS-28 at baseline. However, the different isotypes of baseline RF and ACPA levels accounted for only a small proportion of variance in treatment response (RF: R² between 7 and 12% and ACPA: R² between 4 and 7%). The simultaneous presence of all three isotypes of RF or ACPA had no additive value., Conclusion: Presence as well as the titres of RF and IgM ACPA at baseline are significantly correlated with better response to infliximab treatment. However, this correlation is not strong enough to allow a reliable prediction in individual patients. Trial Registration. ISRCTN Register, http://www.controlled-trials.com/isrctn/, ISRCTN36847425.

Background: To compare immune responses following neoadjuvant chemoradiation therapy in combination with hyperthermia plus surgery to those induced by surgery alone in patients with oesophageal cancer., Methods: Thirty-two patients with histopathologically proven oesophageal cancer, scheduled for potentially curative transhiatal or transthoracic oesophagectomy with (neo, n = 20) or without (control, n = 12) neoadjuvant thermochemoradiation therapy (ThCR) were included. Peripheral blood samples were obtained before ThCR, after 2 weeks of ThCR, 1 day before surgery, on postoperative days 1, 3, 7, and 6 weeks after surgery, for white blood cell counts, lymphocyte subsets and T helper type 1 (Th1) and type 2 (Th2) lymphocyte responses., Results: Neo patients showed a significant decrease in granulocytes and lymphocyte subsets, and T cell cytokines after 2 weeks of ThCR. Only CD8+ (cytotoxic) T cells recovered after ThCR to reach normal levels prior to surgery. In contrast, CD4+ T (helper) cells, and NK- and B cells in neo patients did not recover prior to surgery (all P < 0.05). Oesophagectomy induced a significant increase in granulocytes and a decrease in lymphocytes (and subsets). Only those subsets that had not recovered after ThCR (CD4+ T cells, NK and B cells but not CD8+ T cells), were significantly lower (all P < 0.05) during the entire postoperative study period. Postoperatively, the stimulated cytokine production capacity of Th1 and Th2 cells, corrected for number of T cells, was not significantly different between the groups., Conclusion: Neoadjuvant thermochemoradiation for oesophageal cancer caused significant disturbances of host cellular immunity with reduced T, NK and B cell counts, and differential recovery of cytotoxic and helper T cells leading to prolonged T cell imbalance that extends beyond the time of surgery. The functional and anti-tumour consequences of this immunodisturbance need further investigation, as recovery of T helper cytokine production towards surgery was less impaired than T helper cell counts.

Gaucher disease type I, the most common lysosomal storage disorder, is associated with immunoglobulin abnormalities. We studied the prevalence, risk factors, pathogenesis, and effect of enzyme relation therapy (ERT) on gammopathies in an adult Gaucher disease type I cohort (N = 63) and related the results to a review of the currently available literature. Polyclonal gammopathies and monoclonal gammopathy of undetermined significance (MGUS) in our adult GD I cohort were found in 41% and 19% of patients. These results are similar to the data from the literature and correspond to the increased risk of multiple myeloma (MM) that has been described. The prevalence of MGUS in our cohort increased with age but was not associated with disease severity or exposure time. The serum levels of free light chains of immunoglobulins were measured and were not found predictive for the development of MGUS or MM. Levels of pro- as well as anti-inflammatory cytokines, growth factors, and chemokines, especially those involved in inflammation and B-cell function, are disturbed in GD I, with the most impressive and consisting elevations for interleukin-10 and pulmonary and activation-regulated chemokine. A beneficial effect of ERT on the occurrence and progression of gammopathies was suggested from longitudinal data.

Background: We investigated CD4(+) memory T cell responses to influenza virus (FLU), respiratory syncytial virus (RSV), and nontypeable Haemophilus influenzae (NTHi)., Methods: The precursor frequencies of antigen-specific CD4(+) cells were determined by in vitro expansion of peripheral blood mononuclear cells from healthy individuals (n=9) and patients with chronic obstructive pulmonary disease (COPD; n=16). The expression of CD27 and CCR7 and the production of interferon (IFN)- gamma and interleukin-2 was measured directly ex vivo. Furthermore, the phenotypic and functional properties of CD4(+) T cells residing in the lung were analyzed and compared with those of circulating CD4(+)memory cells from the same donors (n=8)., Results: FLU-, RSV-, and NTHi-specific CD4(+) memory T cells circulated at low frequencies in the peripheral blood of healthy individuals and patients. RSV- and NTHi-specific CD4(+) T cells had a memory phenotype with moderate to high CD27 and CCR7 expression. In contrast to the low frequencies of circulating FLU-specific CD4(+) T cells, we found an enrichment of differentiated CD4(+) FLU-specific cells and high IFN- gamma expression in CD4(+) memory cells in lung tissue., Conclusion: No gross defects were found in circulating CD4(+) memory cells specific for pathogens associated with COPD. However, the large differentiated CD4(+) memory T cell pool residing in the lung may contribute to a large extent to local antiviral immunological protection.

The lungs are frequently challenged by viruses, and resident CD8(+) T cells likely contribute to the surveillance of these pathogens. To obtain insight into local T cell immunity to respiratory viruses in humans, we determined the specificity, phenotype, and function of lung-residing CD8(+) T cells and peripheral blood CD8(+) T cells in a paired analysis. The lung contained markedly higher frequencies of influenza (FLU)-specific and respiratory syncytial virus (RSV)-specific CD8(+) T cells when compared with the circulation. This contrasted with an equal distribution of cytomegalovirus- and Epstein-Bar virus-specific CD8(+) T cells. Noticeably, a substantial fraction of the lung-residing FLU- and RSV-specific CD8(+) T cells had progressed to a relatively late differentiation phenotype, reflected by low expression of CD28 and CD27. Lung-derived FLU-specific CD8(+) T cells had low activation requirements, as expansion of these cells could be initiated by cognate peptide in the absence of helper cell-derived signals. Thus, the human lung contains high numbers of differentiated FLU- and RSV-specific memory CD8(+) T cells that can readily expand upon reexposure to virus. Resident lung T cells may provide immediate immunological protection against pulmonary virus infections.

Hypertonic saline aerosol can elicit airway obstruction in patients with moderate or severe COPD. In the present study we assessed whether cetirizine dihydrochloride is capable of modulating this response. After a screening visit, 20 patients with COPD (mean FEV(1) 49% pred) were treated with cetirizine 10mg daily or placebo over 1 week in a randomized, double-blind, cross-over fashion and measurements performed at the end of treatment periods. At each visit, patients were challenged by 3% saline aerosol (screening: 0.9%) over 5 min after prior inhalation of salbutamol, and 45 min later sputum was obtained after inhalation of 0.9% saline. Lung function was quantified in terms of forced expiratory (FEV(1)) and inspiratory (FIV(1)) volumes. Spirometric values did not differ between visits and salbutamol-induced bronchodilation was not altered by cetirizine. Compared to baseline or post-salbutamol values, the saline-induced fall in FEV(1) was smallest at screening (P<0.01), without a significant difference between treatments. Regarding FIV(1), however, the percent fall from baseline was higher after placebo (Delta=-10.1%; P<0.05) compared to screening (0.4%) or cetirizine (-4.3%). Sputum composition showed no significant differences except for a tendency towards reduced concentrations of alpha(2)-macroglobulin after cetirizine compared to placebo (P=0.045). The present data indicate some, though small, effects of the H1 receptor antagonist cetirizine on hypertonic saline-induced airway obstruction in patients with moderate-to-severe COPD. In view of the mechanisms involved, it is an open question whether stronger effects can be elicited with higher doses and whether such effects would translate into clinical benefits, e.g. during exacerbations.

Background: We investigated respiratory syncytial virus (RSV)-specific CD8(+) memory T cell responses in healthy control participants (n=31) and in patients with chronic obstructive pulmonary disease (COPD) (n=9), with respect to frequency, memory phenotype, and proliferative requirements., Methods: The properties of RSV-specific CD8(+) T cells were analyzed by use of RSV tetramers. The proliferative requirements of RSV-specific CD8(+) T cells were analyzed by culture of peripheral-blood mononuclear cells with RSV peptide in combination with distinct cytokines., Results: RSV-specific CD8(+) memory T cells showed a high level of expression of CD27 and interleukin-7R alpha and a low level of expression of CCR7. In the healthy participants, the frequency of RSV tetramer(+) CD8(+) T cells was significantly lower than the frequency of influenza virus A (FLU) tetramer(+) CD8(+) T cells (P=.0001). In contrast to FLU tetramer(+) CD8(+) T cells, we could detect RSV tetramer(+) CD8(+) T cells in the subgroup of elderly healthy participants (age, > or =55 years) and in the patients with COPD only after in vitro expansion. Expanded RSV-specific T cells produced interferon- gamma and granzyme B., Conclusion: We provide evidence that a pool of functional RSV-specific CD8(+) memory T cells persists in the peripheral blood of healthy individuals and patients with COPD. Low numbers of RSV-specific memory T cells in the elderly and in patients with COPD may explain the increased susceptibility to RSV infection in these populations.

Reduced serum IgG and subclass levels have been demonstrated in children with chronic renal failure. To study possible causes of this reduction, we analysed B cell subset composition, T helper cell frequencies and immunoglobulin (Ig) production capacity in vitro in children with chronic renal failure, with or without dialysis treatment. B cell subsets were characterized by determining CD27, IgM, IgD and CD5 expression within the CD19(+) population. Intracellular expression of interferon (IFN)-gamma, interleukin (IL)-2 and IL-4 in PMA/ionomycin-stimulated peripheral blood mononuclear cells (PBMC) was used to evaluate T helper frequencies. The capacity of B cells to secrete Ig in vitro was determined by measuring IgG(1), IgG(2) and IgM in culture supernatants of anti-CD2/CD28 monoclonal antibody (MoAb)- or SAC/IL-2-stimulated PBMC. Memory B cell numbers (identified as percentage or absolute number of CD19(+) IgM-IgD- or CD19(+)CD27(+) lymphocytes) were lower in children treated with haemodialysis (HD), peritoneal dialysis (PD) and children with chronic renal failure before starting dialysis treatment (CRF) compared to healthy controls (HC) (P < 0.05). Compared with HC, CD5(+) (naive) B cells were reduced in HD-treated patients but not for PD or for children with chronic renal failure before starting dialysis treatment (CRF). No significant differences in CD4(+) T helper cell subsets were found between the groups. However, CRF children had a higher percentage of IFN-gamma producing CD8(+) T lymphocytes compared to HC (P = 0.02). Finally, IgG(1), IgG(2) and IgM production in vitro was similar in the four groups. In conclusion, significantly lower numbers of memory type B cells were found in children with chronic renal failure compared to healthy controls. This reduction may contribute to the low Ig levels found in these children.

Background: Phagocytosis of IgG- or complement-opsonized bacteria and antibody production by lymphocytes are regulated by cell surface receptors for IgG (FcgammaRI, FcgammaRII and FcgammaRIII) and complement (CR1 and CR3). We measured the effect of uraemia and dialysis treatment on FcgammaR and CR expression on leukocytes in blood., Methods: Blood samples were obtained from children: 40 treated with peritoneal dialysis (PD), 23 with haemodialysis (HD), 46 not yet dialysed (CRF) and 33 healthy (HC). White blood cells, isolated from EDTA-blood by centrifugation after cell fixation with paraformaldehyde, were labelled with FITC-conjugated CD16 (FcgammaRIII), CD32 (FcgammaRII), CD64 (FcgammaRI), CD11b (CR3) and CD35 (CR1) monoclonal antibodies and analysed by flow cytometry., Results: In PD, HD, CRF and HC, monocytes and neutrophils were all positive for FcgammaR and CR, except for CD16 on monocytes (20% positive). Lymphocytes expressed CD16 and CD32 but not CD64. PD, HD and CRF children had lower percentages of CD16(+) and CD32(+) lymphocytes compared with HC. The percentage of CD11b(+) lymphocytes was lower only in PD and the percentage of CD35(+) lymphocytes was lower in HD and CRF compared with HC. The median CD32 mean fluorescense intensity (MFI) on lymphocytes, monocytes and neutrophils was lower in PD, HD and CRF compared with HC. On the other hand, CD11b MFI on lymphocytes, monocytes and neutrophils was higher in PD, HD and CRF children compared with HC. CD16 and CD64 MFI were not different among the groups and CD35 MFI was only lower on lymphocytes from PD, HD and CRF compared with HC., Conclusions: In children with chronic renal failure, whether dialysed or not, FcgammaRII expression on lymphocytes, monocytes and neutrophils was reduced and CR3 expression was increased. Furthermore, CR1 expression on lymphocytes, important for the humoral response, was lower in children with renal failure. Age and uraemia are associated with these abnormalities and might contribute to impaired immune function in children with chronic renal failure.

CD8(+) T lymphocytes play a major role in the clearance of respiratory syncytial virus (RSV) infections. To be able to study the primary CTL response in RSV-infected children, epitopes presented by a set of commonly used HLA alleles (HLA-A1, -A3, -B44 and -B51) were searched for. Five epitopes were characterized derived from the matrix (M), non-structural (NS2) and second matrix (M2) proteins of RSV. All epitopes were shown to be processed and presented by RSV-infected antigen-presenting cells. HLA-A1 tetramers for one of these epitopes derived from the M protein were constructed and used to quantify and phenotype the memory CD8(+) T cell pool in a panel of healthy adult donors. In about 60 % of the donors, CD8(+) T cells specific for the M protein could be identified. These cells belonged to the memory T cell subset characterized by expression of CD27 and CD28, and down-regulation of CCR7 and CD45RA. The frequency of tetramer-positive cells varied between 0.4 and 3 per 10(4) CD8(+) T cells in PBMC of healthy asymptomatic adult donors.

Introduction: Recent studies have indicated that the cytokines produced by CD4(+) T helper type 1 (T(h)1) and type 2 (T(h)2) cells are critically important in antitumour immunity and perhaps clinical outcome. From this perspective, we investigated the immunocompetence of patients with previously untreated cancer of the oesophagus or oesophagogastric junction (OGJ) in relation to stage of disease and postoperative survival., Methods: Blood samples were taken prior to surgery from 32 patients with adenocarcinoma of the oesophagus or OGJ. Ten healthy volunteers served as normal controls. T-cell and monocyte subpopulations were determined using flow cytometry. Monocyte as well as T(h)1- and T(h)2-lymphocyte cytokine levels were assessed in stimulated whole blood cultures., Results: Absolute T-cell and monocyte (subset) counts as well as monocyte cytokine levels were similar among patients and controls. Production of T(h)1-type cytokines was higher in patients than in controls (IFN-gamma, p=0.01; IL-2, p=0.05), whereas T(h)2-type cytokine levels were comparable (IL-4, p=0.5; IL-13, p=0.3). T-cell CD4(+)/CD8(+) ratios decreased as pTNM stage worsened (stage I/II vs stage III/IV, p=0.009). Of all measured immunological parameters, only IL-2 production significantly affected both overall survival ( p=0.015) and disease-free survival ( p=0.0062). High IL-2 levels corresponded with a favourable prognosis., Conclusions: Patients awaiting surgery for adenocarcinoma of the oesophagus or oesophagogastric junction demonstrated a shift in the T(h)1/T(h)2 balance-in favour of T(h)1-compared with healthy volunteers. The ability of T cells to produce IL-2 was related to survival indicating a crucial role of T(h)1-type cells in antitumour immunosurveillance.

Objective: To investigate alterations in immune responses after transhiatal versus transthoracic esophageal resection and to evaluate the role of preoperative immune functions in predicting postoperative infectious complications., Summary Background Data: Impaired immune defense is associated with a decreased resistance to infection. Patients undergoing esophageal resection via a transhiatal or transthoracic approach are prone to develop infectious complications. There are no randomized data on immune responses after two major surgical interventions., Methods: The study group consisted of 20 patients who were randomly allocated to a limited transhiatal or extended transthoracic esophagectomy for cancer. Blood samples were taken before the operation and at regular intervals thereafter from day 1 to day 10. Monocyte and T-helper type 1 (Th1) and type 2 (Th2) lymphocyte functions were assessed in stimulated whole blood cultures., Results: Both surgical groups had severely depressed in vitro production of interleukin (IL)-12, IL-10, interferon-gamma, IL-2, IL-4, and IL-13 on postoperative day 1. Depression of Th2-type cytokine production was more profound after transthoracic than after transhiatal esophagectomy (IL-4, P=.005; IL-13,P=.007). Postoperative reduction in Th1-type cytokine production was similar between the two groups (interferon-gamma, P=.40; IL-2, P=.06). Irrespective of the surgical approach, patients who developed major infectious complications after surgery presented with a diminished T-cell cytokine production before the operation compared to those who had a relatively uneventful recovery (IL-4, P=.045; interferon-gamma, P=.064). In regression analysis, the occurrence of postoperative major infection was best predicted by increased duration of anesthesia ( P<.0001) and low preoperative interferon-gamma production ( P=.006)., Conclusions: Both transhiatal and transthoracic esophagectomy induced severely depressed monocyte and T-lymphocyte cytokine production. The extent of the surgical procedure had a differential immunosuppressive impact on Th2-type but not on Th1-type cell activity, indicating that the two Th pathways were downregulated through distinct mechanisms. Preoperative interferon-gamma determination would be useful to anticipate the occurrence of postoperative major infectious complications.

In patients with allergic asthma, T-cell cytokines are implicated in the regulation of the local inflammation in the airways. The ability of sensitized mast cells to release mediators and cytokines early upon allergen stimulation makes them important candidates for local immunoregulation. We have studied the effects of human mast cells on T cells with the use of the human mast cell line HMC-1. We showed that activated human mast cells or their soluble products induced and enhanced the interferon-gamma (IFN-gamma) production by T cells up to about 60-fold. The production of interleukin (IL)-4 was hardly affected and that of IL-5 was slightly enhanced. The enhancement of IFN-gamma production was induced both in polyclonal CD4+ and CD8+ T cells and in CD4+ and CD8+ T-cell clones. Further characterization of the factors involved demonstrated a molecular mass above 30 000. Our results implicate that by this mechanism mast cells may account for a negative feedback system locally down-regulating allergen-induced T helper 2 responses via IFN-gamma production by the T cells.

Dogs with immunoglobulin E (IgE) allergy for ragweed that are sensitized by intrapulmonary exposure to ragweed can be used to study the pulmonary immune response that is important in allergic asthma. Using this model, we tested the hypothesis that T lymphocytes are activated locally in the airways shortly after allergen exposure of the lungs. The airways of six allergic dogs and three non-allergic dogs were exposed to ragweed by segmental allergen challenge (SAC). T-cell subsets and T-cell activation in blood and bronchoalveolar lavage (BAL) fluid were measured by flow cytometry before SAC and at 4, 24 and 72 hr thereafter. SAC caused a statistically significant increase in the percentage of major histocompatibility complex (MHC) class II-positive CD4 and CD8 T cells in BAL fluid and a significant increase in the mean fluorescent activity of MHC class II from 4 hr after SAC onward. This activation was significantly different from that found in cells from lung lobes challenged with saline, or from lung lobes in non-allergic dogs challenged with ragweed. The percentage of CD45RA(bright) CD8 cells increased significantly in allergic dogs after both ragweed and saline challenges. This was significantly higher than in non-allergic dogs. We conclude that T-cell activation in the airways of dogs can be measured after in vivo activation of the cells by measuring MHC class II and CD45RA expression in BAL fluid T cells. Furthermore, in allergic dogs, T cells are activated locally in the lungs within 4 hr after exposure to ragweed allergen. These results suggest a role for T lymphocytes in the development of late-phase allergic reactions in the airways.

Human papillomavirus (HPV) infections play an important role in the development of cervical neoplasia. To get to a better understanding of the role of cytokines in the development of these neoplasias, we analysed the presence of various cytokines in cervicovaginal washings of healthy volunteers (n=22), cervical intraepithelial neoplasia (CIN) patients (n=63) and cervical cancer patients (n=33). IL-12p40, IL-10, TGF-beta1, TNF-alpha and IL-1beta levels were significantly higher in patients with cervical cancer than in controls and CIN patients. The levels of IFN-gamma were not different. Our data demonstrate alterations in the local cervical immune environment in cervical cancer patients. This could have important consequences for the further development of immune modulating therapies and vaccination strategies., (Copyright 2001 Academic Press.)

Nonencapsulated Haemophilus influenzae often causes chronic infections of the lower respiratory tract in both nonobstructive and obstructive chronic bronchitis. We assessed airway inflammation in clinically stable, chronically H. influenzae-infected patients with nonobstructive (CB-HI, n = 10) and in patients with obstructive chronic bronchitis (COPD-HI, n = 10) by analyses of the sol phase of spontaneously expectorated sputum (SSP). As compared with the CB-HI group, the COPD-HI group had significantly higher (p < 0.05) levels of myeloperoxidase (MPO) and tumor necrosis factor (TNF)-alpha in their SSP, whereas the degree of plasma protein leakage (SSP-to-serum ratio of plasma proteins) and the levels of interleukin (IL)-8, secretory IgA, and lactoferrin were similar in the two groups. These findings point to differences in pathophysiology in CB-HI and COPD-HI. The high level of TNF-alpha in the SSP of COPD-HI patients is in accord with the proposed role of TNF-alpha in the development of airway obstruction in COPD patients. In apparent contradiction, low levels of TNF-alpha were found in the SSP of noninfected but otherwise similar COPD patients (n = 9). This finding, however, does not exclude an exaggerated TNF-alpha response to infection or another stimulus in the airways of COPD patients. The SSP levels of MPO and IL-8, and the degree of plasma protein leakage in the COPD-HI group, were retrospectively compared with and found significantly higher than those of noninfected COPD patients, suggesting a more marked inflammatory response in COPD-HI. Whether this reflects a direct cause-and-effect relationship should be addressed in a future long-term prospective study involving repeated measurements in the same patients.

Background: It is not clear whether low serum levels of IgG (subclasses), previously demonstrated in children on peritoneal dialysis (PD), are related to the PD procedure or to factors associated with chronic renal failure (CRF). The aim of our study was to analyze the effect of PD on serum and PD effluent (PDE) IgG and subclass levels in children with end-stage renal failure., Methods: We measured albumin, IgG, IgA, IgM, and IgG subclasses in serum and PDE from children on PD (N = 40) and compared the serum values with those of children treated with hemodialysis (HD, N = 23) or presenting with CRF but not yet dialyzed (CRF; N = 63), and with a group of healthy controls (HCs; N = 67). Sixteen PD children could be followed sequentially from before starting PD and eight during a peritonitis episode., Results: Forty percent of the PD children showed reduced serum IgG2 levels (P = 0.0003) compared with 35% in HD (P = 0.006), 33% in CRF (P = 0.001), and 9% in HC children. IgG1 deficiencies were observed in 25% of PD patients (P < 0.0001), 4% of HD (P = NS), 16% of CRF (P = 0.0005), and 0% of HC children. IgG3 and IgG4 deficiencies were observed less frequently. Peritoneal clearances were similar for total IgG, IgG1, IgG2, and IgG4, but were lower for IgG3 (P < 0.05). No relationships were found between clearances and age or duration of PD treatment. Total IgG (P = 0. 003) and IgG1 (P = 0.002) levels declined just after starting PD. Peritonitis was associated with temporarily increased peritoneal loss of Ig, while the serum concentrations were unaffected. No significant relationship was found between the peritonitis incidence and reduced IgG or subclasses. However, all children with two or more peritonitis episodes per year had a reduced Ig level., Conclusions: Although the mean serum concentrations of immunoglobulins were normal in all studied groups, a deficiency of one or more IgG subclasses was present in all groups with renal failure, suggesting inhibition of their synthesis by the uremic state. Ig deficiencies were more frequently found in PD, likely caused by protein loss in PDE. A high peritonitis incidence was associated with reduced serum Ig levels.

IL-6 mRNA and protein expression in human airway epithelial-like H292 cells depends on rapid, but regulable IL-6 mRNA degradation. We restricted IL-6 mRNA degradation by partially inhibiting protein synthesis and studied the IL-6 response. Despite partial inhibition of protein synthesis, IL-6 protein production was increased and prolonged. Furthermore, the threshold concentration for stimuli of IL-6 protein production decreased and the dose-response curves became steeper. Similar findings were obtained with primary human bronchial epithelial cells. This exaggerated production may apply to other proteins encoded by labile mRNA and is likely to occur during viral infection of airway epithelial cells., (Copyright 2000 Academic Press.)

Individuals with either a late (C5-9) complement component deficiency (LCCD) or properdin deficiency are at increased risk to develop meningococcal disease, often due to serogroups W135 and Y. Anti-meningococcal defence in both LCCD persons and properdin-deficient individuals without bactericidal antibodies depends mainly on phagocytosis. Three types of opsonin receptors are involved in phagocytosis by polymorphonuclear cells (PMN). These represent the polymorphic FcgammaRIIa (CD32) and FcgammaRIIIb (CD16b) receptors, and the C3 receptor CR3 (CD11b/CD18). When the distribution of FcgammaRIIa and FcgammaRIIIb allotypes was assessed in 15 LCCD and in 15 properdin-deficient patients with/without previous meningococcal disease, we found the combination of FcgammaRIIa-R/R131 with FcgammaRIIIb-NA2/NA2 allotypes to be associated with previous meningococcal disease (odds ratio 13.9, Fisher's test P = 0.036). No such relation was observed in the properdin-deficient patients. The importance of FcgammaRIIa allotypes was also demonstrated using in vitro phagocytosis assays. PMN from FcgammaRIIa-R/R131 homozygous donors internalized IgG2 opsonized meningococci W135 significantly (P < 0.05) less than PMN from FcgammaRIIa-H/H131 donors. When properdin-deficient serum was tested, it was observed that reconstitution with properdin resulted in enhanced PMN phagocytosis of the W135 meningococci (P = 0.001). This enhanced phagocytosis was parallelled by an increase in C3 deposition onto the opsonized meningococci W135 (r = 0.6568, P = 0. 01). We conclude that the occurrence of meningococcal disease in LCCD patients is associated with certain FcgammaR allotypes. Properdin-deficient individuals are susceptible to meningococcal disease because of an insufficient C3 deposition on the surface of meningococci, resulting in insufficient phagocytosis.

Plasma protein exudation into the airways is an important pathophysiological event in asthma. The effect of 12 wk of treatment with inhaled fluticasone propionate (FP; 250 microgram twice a day) or salbutamol (Sb; 400 microgram twice a day) on plasma protein leakage was compared in a double-blind, randomized parallel-group study of 30 patients with asthma. Primary outcomes were plasma protein leakage and size selectivity of the blood-airway lumen barrier, cell differentials in BAL fluid, and bronchial responsiveness to histamine (PC20histamine). Two independent procedures to account for the effect of variable dilution of BAL on the levels of albumin (Alb) and alpha2-macroglobulin (A2M) in BAL fluid consisted of correction based on urea levels and on the application of the relative coefficient of excretion [RCE = ([A2M] in BAL fluid/[A2M] in serum)/([Alb] in BAL fluid/[Alb] in serum)]. In the FP group a significant decrease was found in the A2M level and the RCE, and in the percentage of eosinophils in BAL fluid. The PC20histamine increased significantly (mean increase, 2.4 doubling doses), whereas PC20histamine decreased in the Sb group. Differences between groups were significant except for the decrease in eosinophils. We conclude that 12 wk of FP (250 microgram twice a day) decreased the permeability of the blood-airway lumen barrier, in particular for high molecular weight proteins.

Interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) synergize to express polymeric immunoglobulin receptor (pIgR) but their combined effect, and that of IL-4 alone, on secretory immunoglobulin A (sIgA) release is unknown. Recently, we have developed an airway epithelial cell model that allows assessment of the integrated effect of a stimulus on pIgR gene and protein expression and sIgA release. With this model we show here that IL-4 and IFN-gamma dose-dependently increased pIgR mRNA and protein expression, and sIgA release. IFN-gamma and IL-4 induced similar maximal expression of pIgR, but IFN-gamma enhanced sIgA release more than IL-4. When added together, IL-4 and IFN-gamma synergistically increased pIgR mRNA and protein expression, but sIgA release was stimulated in an additive manner. Thus, IL-4 and IFN-gamma may be implicated in the increase of sIgA levels as found in mucosal inflammatory diseases. In addition, our results indicate that transport and release of empty pIgR is subject to regulatory mechanisms different from those of pIgR with bound dimeric IgA.

High levels of histamine can be found in the airways of asthma patients. This study describes the effects of histamine on anti-CD3-induced production of IL-4, IL-5, and IFN-gamma by T cell clones from subjects with allergic asthma and healthy subjects. T cell clones were obtained from bronchoalveolar lavage (BAL) fluid and blood. The number of clones tested, and the percentage of clones in which histamine inhibited or enhanced cytokine production by more than 25%, were as follows: IL-4, 47, 8.5%, and 4.3%; IL-5, 43, 14%, and 30%; and IFN-gamma, 52, 40%, and 15%. Inhibition of IL-5 and IFN-gamma production was reversed by IL-2. The enhancement of IFN-gamma production was associated with an enhancement of both IL-2 production and proliferation. In 21% of the clones a combined effect consisting of inhibition of IFN-gamma production and enhancement of IL-5 production was found. This response was reversed by H2-receptor antagonists and was significantly associated with a histamine-induced increase in intracellular levels of cAMP. The role of cAMP in mediating the histamine effects was supported by the observations that the beta2-agonist salbutamol had effects similar to histamine and that high concentrations of PGE2 mimicked the inhibitory effects of histamine. Clones from BAL fluid and blood showed similar responses, as did clones from patients with asthma and from control subjects. The enhancement of IFN-gamma production by histamine, however, was found only in clones from healthy subjects. The results warrant further investigations on the role of cAMP in the regulation of cytokine production.

IgG in dialysate may have an important role in anti-infection mechanisms during continuous ambulatory peritoneal dialysis (CAPD). As Fc fragment oligosaccharidic chains are crucial for IgG effector functions, we have tested the hypothesis that IgG glycation might occur during CAPD and modify IgG properties. Purified normal IgG was incubated with glucose solutions of different concentrations and pH. Separation of glycated IgG was performed by affinity chromatography. Complement activation (C3c deposition) and phagocytosis by polymorphonuclear leucocytes (PMN) were studied in vitro using Staphylococcus aureus Wood (STAW) as antigen. In addition, we compared the percentages of glycated IgG in IgG purified from sera and dialysates of 12 CAPD patients. The percentage of glycated IgG after in vitro incubation of normal IgG with glucose solutions was directly proportional to glucose concentrations, incubation time and pH. Glycated IgG anti-STAW induced a higher C3c deposition than non-glycated IgG anti-STAW (C3c/IgG (mean +/- SD) 0.96 +/- 0.06 vs 0.79 +/- 0.08; P = 0.027). PMN phagocytosis was not affected by IgG glycation. The percentages of glycated IgG in dialysates of CAPD patients were greater than those in corresponding sera (5.38 +/- 2.36% vs 4.56 +/- 2.47%; P = 0.006). It is concluded that IgG glycation may take place in the peritoneal cavity during CAPD and lead to enhanced complement activation. This could explain the high degree of complement activation previously described in dialysate of CAPD patients and might theoretically result in a reduction of complement factors available in dialysate for adequate anti-infection mechanisms.

Psoriasis is a T-cell-mediated inflammatory skin disease which can be treated successfully with immunosuppressive drugs. Our purpose was to evaluate disease activity of psoriasis and the effect of immunosuppressive treatment by monitoring the soluble T-cell products sIL-2R, sCD27, sCD4, sCD8 and sICAM-1. Twenty-two patients were treated orally with escalating dosages of cyclosporin A (n = 17)(3-5 mg/kg/day) or FK506 (n = 5)(0.05-0.15 mg/kg/day). The Psoriasis Area and Severity Index (PASI) was used to monitor clinical activity of psoriasis. Serum samples were analyzed by ELISA. sIL-2R levels showed the highest correlation with psoriasis disease activity (rs = 0.89; p < 0.05). The longitudinal part of this study showed that levels of sIL-2R and sCD27 decreased during immunosuppressive treatment but remained above normal even in patients successfully treated. Our data indicate that sIL-2R levels are well correlated with disease activity in patients with psoriasis. sIL-2R levels closely follow the decrease of disease activity during immunosuppressive treatment.

The four subclasses of IgG have different biological activities associated with their Fc regions. Fc gamma receptors on leucocytes (Fc gamma R) mediate binding and phagocytosis of opsonized particles. Two structurally and functionally distinct allelic polymorphisms of the Fc gamma R have been defined: the H/R131 forms of Fc gamma RIIa (CD32), and the neutrophil antigen 1 (NA1)/NA2 forms of Fc gamma RIIIb (CD16). In this study the activities of allotypes of CD16 are analysed with antibacterial IgG subclass antibodies and with IgG1 and IgG3 anti-Rhesus D, and the activities of CD32 with IgG1 and IgG3 anti-Rhesus D. With respect to the allotypes of CD16, polymorphonuclear leucocytes (PMN) homozygous for Fc gamma RIIb-NA2 exhibited a lower (21-25%) IgG1-mediated phagocytosis of Staphylococcus aureus strain Wood (STAW), Haemophilus influenzae type b (Hib), and Neisseria meningitidis group B (NMen) than IIIb-NA1 PMN. The difference was apparent only when the micro-organisms were opsonized in the absence of complement, and was furthermore enhanced (34-52%) upon blockade of Fc gamma RIIa. In addition, monoclonal IgG3 anti-D-mediated rosette formation and phagocytosis was consistently found to be lower (16%) with Fc gamma RIIIb-NA2 than with IIIb-NA1 PMN. For the allotypes of CD32 we now show that IgG3 anti-D sensitized erythrocytes formed more (50%) rosettes and were phagocytosed at a higher rate with PMN carrying Fc gamma RIIa-H131 than with PMN carrying IIa-R131. Heterozygous Fc gamma RIIa-H/R131 PMN exhibited intermediate phagocytic activity in this respect. This study illustrates a critical role of Fc gamma R allotypes in functional interactions with biologically relevant IgG subclass antibodies.

Antibodies are essential in host defense against Neisseria meningitidis. Therefore, interactions among IgG and Fc receptors (Fc gamma R) on phagocytes may be crucial. Genetic polymorphic forms of Fc gamma RIIa (CD32) express different functional activities. In a retrospective study, Fc gamma R polymorphisms were determined in 25 children who survived fulminant meningococcal septic shock: 11 had Fc gamma RIIa-R/R131, the poor IgG2-binding allotype, which is a significantly more frequent rate than found in a healthy white population (44% vs. 23%; P = .028; odds ratio = 2.67; 95% confidence interval, 1.09-6.53). The relevance of this finding was further supported by the fact that neutrophils with the Fc gamma RIIa-R/R131 allotype phagocytized N. meningitidis opsonized with polyclonal IgG2 antibodies less effectively than did IIa-H/H131 neutrophils. Our findings suggest an important role for anti-N. meningitidis IgG2 and the Fc gamma RIIa polymorphism in host defense against systemic meningococcal infections.

To obtain information on effector functions of human immunoglobulin G2 (IgG2), we have measured the complement-activating properties of polyclonal IgG subclass antibodies against bacterial antigens. IgG1 and IgG2 were purified from serum samples from five healthy individuals, and complement activation was measured with different bacterial antigens. We used Staphylococcus aureus Wood 46 (STAW), which is a common antigen, Haemophilus influenzae type b (Hib), which is a common pathogenic microorganism in children, and formaldehyde-inactivated tetanus toxin (TT). Bacteria were incubated with antibodies and then incubated with sera from agammaglobulinemic patients as a complement source, and C3c deposition was measured by enzyme-linked immunosorbent assay. We found that anti-STAW IgG2 activated complement to a level similar to that of anti-STAW IgG1. Anti-Hib IgG1 complement activation was as much as seven times higher than that of anti-Hib IgG2 in four individuals. In one individual, anti-Hib IgG2 was more effective in complement activation than anti-Hib IgG1. Anti-TT antibodies showed patterns similar to those of anti-Hib. Our results indicate that IgG2 antibodies may contribute significantly to antibacterial defense. Also, individual differences in antibody effector functions should be taken into account when evaluating the immune status of patients and during early phase 1 studies of new vaccines.

Concentrations of IgG2, IgG4 and IgE were low in 16, 24 and 20% of 25 persons with selective IgA deficiency. Fifty-two per cent had IgD concentrations below 5 iu/ml. Trends for association between any of these parameters and the presence of clinical symptoms were not significant. All patients, except one, had normal amounts of Ig-bearing lymphocytes in the blood. IgG1 antibodies against casein were increased in titre and frequency, whereas IgG4 antibodies were normal. Similar results were found in other sera from persons with selective IgA deficiency.

The primary immune response in vivo of 20 patients with selective IgA deficiency was studied and compared to controls. The primary cellular immune response tested by dinitrochlorobenzene (DNCB) was decreased in many patients. The primary humoral immune response was elicited by immunization with the test immunogen Helix pomatia haemocyanin (HPH). Using a direct ELISA technique antibodies against HPH of the IgA, IgG and IgM class were measured. Two weeks after immunization no response of IgA anti-HPH was seen except in three patients who showed a low but detectable antibody level. In spite of normal or even elevated serum IgG and IgM levels there was a significantly lower response of the IgG and IgM anti-HPH antibodies at 2 weeks after immunization as compared to the controls followed by a further decline at 6 weeks. We conclude that selective IgA deficiency is often accompanied by more general disturbances in humoral and cellular immunity to newly encountered antigens.