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T follicular helper (Tfh) cells drive humoral immunity by facilitating B cell responses at the initial and recall phases. Recent studies have indicated the possible involvement of Tfh cells in the process of chronic inflammation. However, the functional role of Tfh cells in persistent immune settings remains unclear. Here, we report that CD4

Background: CXCR5+ T follicular helper (TFH) cells primarily promote B cells to produce an antigen-specific antibody through germinal centers (GCs). TFH cells exist in circulation, and circulating(c) TFH2 cells, a subset of cTFH cells, are able to help naïve B cells produce IgE in healthy individuals. Conversely, IL-10-producing regulatory B (Breg) cells inhibit an accelerated immune response. Methods: We investigated the roles of cTFH cells and cBreg cells based on a TH2 response in patients with atopic asthma (AA). Thirty-two patients with AA and 35 healthy volunteers (HV) were enrolled. We examined cTFH cells including their subsets, their expression of ICOS and PD-1, and cBreg cells by flow cytometry and their associations with clinical biomarkers. Plasma levels of CXCL13, which is a counterpart of CXCR5, were also measured using ELISA. Results: In patients with AA, cTFH2 cells were increased and cTFH1 cells were decreased compared with those in HV. The expression levels of ICOS on cTFH and their subset cells were elevated and Breg cells were greatly decreased. The plasma levels of CXCL13 in patients with AA were significantly elevated and correlated well with the cTFH2/cBreg ratio. These cells were examined in 10 patients AA before and after inhaled corticosteroid (ICS) treatment. Interestingly, the percentages and numbers of TFH2 and ICOS+ cTFH cells declined after ICS treatment together with improvements in symptoms and clinical biomarkers. Conclusions: The percentages and numbers of cTFH2 and ICOS+ cTFH cells might be useful as biomarkers of TH2 typed airway inflammation in patients with AA. Keywords: CXCL13, ICS, IgE, Regulatory B cell, T follicular helper cell

IgG4-related disease (IgG4-RD) is a chronic fibroinflammatory disease characterized by elevation of serum IgG4 level as well as infiltration of IgG4+ plasma cells in various affected organs. The etiology of IgG4-RD is still not fully understood. Since IgG4-RD is more prevalent in the elderly, aging in itself is considered to be an important risk factor of IgG4-RD. However, the relationship between the pathogenesis of IgG4-RD and immunosenescence remains unknown. To clarify age-related features underlying IgG4-RD, we focused on T follicular regulatory (Tfr) cells, which share forkhead box P3 with regulatory T cells, since the percentage of Tfr cells is known to depend on age. Studies of blood specimens from patients with IgG4-RD and from healthy volunteers demonstrated a marked elevation of circulating Tfr (cTfr) cells in patients with IgG4-RD. Moreover, the percentage of cTfr cells was significantly correlated with various clinical parameters including the level of serum IgG4 and the number of involved organs in IgG4-RD patients. The percentages of tonsillar and blood Tfr cells were increased with aging in healthy volunteers, whereas the suppressive effect of cTfr cells on B cell function in elderly subjects was impaired in comparison with that in young subjects due to a defect in the production of a regulatory cytokine, IL-10. Given that the number of IL-10-producing cTfr cells in IgG4-RD patients was markedly increased compared with that in healthy elderly subjects, these findings suggest that an abnormal aging process of Tfr cells may be related to the pathogenesis of IgG4-RD.

Background: Many studies have attempted to clarify the factors associated with serum periostin levels in asthmatic patients. However, these results were based on studies of subjects mainly characterized by high eosinophil counts, which may present as an obstacle for clarification in the identification of other factors associated with serum periostin levels. The aim of this study was to determine the factors associated with serum periostin levels in healthy subjects. We also assessed some factors in asthmatic subjects to confirm their extrapolation for management of asthma. Methods: Serum periostin levels were measured in 230 healthy subjects. Clinical factors of interest included body mass index (BMI) and allergic rhinitis (AR). Additionally, we confirmed whether these factors were associated with serum periostin in 206 asthmatic subjects. We further evaluated several obesity-related parameters, such as abdominal fat distribution and adipocytokine levels. Results: Smoking status, blood eosinophil count, total immunoglobulin E, and the presence of AR were associated with serum periostin in healthy subjects. There was a negative association between BMI and serum periostin in both healthy and asthmatic subjects, while there was a tendency of a positive association with AR in asthmatic subjects. There were no differential associations observed for subcutaneous and abdominal fat in relation to serum periostin in asthmatic subjects. Serum periostin was significantly associated with serum levels of adiponectin, but not with leptin. Conclusions: Our results provided clarity as to the factors associated with serum periostin levels, which could be helpful in the interpretation of serum periostin levels in clinical practice. Keywords: Asthma, Healthy subjects, Obesity, Periostin, Rhinitis

The aim of this study was to determine pathological features of T peripheral helper (Tph)-like (PD-1Tph-like cells in the blood and submandibular glands (SMGs) from IgG4-RD patients were analyzed by flow cytometry. Correlations between level of a Tph-like cell subset and clinical parameters of IgG4-RD were investigated. The cytotoxic capacity of Tph-like cells was also examined. Expression profiles of a molecule related to a Tph-like cell subset in IgG4-RD SMGs were assessed by immunohistochemistry.Tph-like cells from IgG4-RD patients highly expressed a fractalkine receptor, CX3CR1. Percentages of circulating CX3CR1CX3CR1

Background T follicular helper (Tfh) cells have been identified as a new category of helper T cells, which express CXCR5 on their surface and induce the production of antigen-specific antibodies. Many investigations have found morbid proliferation and/or activation of Tfh cells in systemic autoimmune and allergic diseases. It is also known that Tfh cells are regulated by regulatory B (Breg) cells in the deteriorating such diseases. Recently, CXCL13, a ligand of CXCR5, has been reported to increase in the peripheral blood and lungs of patients with idiopathic pulmonary fibrosis (IPF). This study aimed to investigate the involvement of Tfh cells and Breg cells in IPF. Methods Peripheral blood samples were obtained from 18 patients with IPF. We isolated heparinized peripheral blood mononuclear cells and investigated the proportions of Breg cells, Tfh cells, PD-1+ICOS+ Tfh cells (activated form of Tfh cells), and the Tfh-cell subsets by flow cytometry. These cell profiles were compared with those of 21 healthy controls. Furthermore, we investigated the correlations between profiles of lymphocytes and lung physiology. Results The median proportions of Tfh cells per total CD4+ T cells and of PD-1+ICOS+ proportion of Tfh cells per total Tfh cells was significantly more in the IPF patients (20.4 and 5.2%, respectively) compared with healthy controls (15.4 and 2.1%, respectively; p = 0.042 and p = 0.004, respectively). The proportion of Tfh2 cells per total Tfh cells was significantly higher and the proportion of Tfh17 was smaller in the IPF patients than healthy controls. The percentage of Breg cells to total B cells was significantly decreased in the IPF patients (median, 8.5%) compared with that in the controls (median, 19.7%; p r = 0.583, p = 0.018). Conclusion Proliferation and activation of Tfh cells and a decrease in Breg cells were observed in the peripheral blood of patients with IPF. The profile of the Tfh-cell subset also changed. Specific humoral immunity aberration would likely underlie complicated pathophysiology of IPF.

T follicular helper (Tfh) cells are involved in specific humoral immunity at initial and recall phases. The fact that the transcription repressors B-cell lymphoma-6 and Blimp-1 determine lineages of Tfh cells and other types of effector CD4(+) T cells, respectively, suggests that there are unique mechanisms to establish Tfh-cell identity. In this study, we found that Tfh cells preferentially express the transcriptional coactivator Bob1. Bob1 of Tfh cells was dispensable for the expression of B-cell lymphoma-6 and the functional property of the cells for B cell help. However, upon initial immunization of foreign antigens, the percentages of Tfh cells in Bob1(-/-) mice were much higher than those in wild-type (WT) mice. In addition, expansion of Tfh cells within Bob1(-/-) CD4(+) T cells transferred into WT mice revealed that the high frequency of Tfh cells was caused by a T-cell-intrinsic mechanism. These findings were further supported by the results of in vitro studies demonstrating that Bob1(-/-) Tfh cells had greater proliferative activity in response to stimuli by CD3/CD28 monoclonal antibody and were also refractory to CD3-induced cell death in comparison to WT Tfh cells. These results suggest that Tfh cells harbor a Bob1-related mechanism to restrict numerical frequency against stimulation of TCRs.

IgG4-related disease (IgG4-RD) is a chronic fibroinflammatory disease characterized by elevation of serum IgG4 level as well as infiltration of IgG4

Objective The aim was to study the pathological role of lymphocytes with a peripheral T helper-cell-like phenotype (PD-1+CXCR5−CD4+) in IgG4-related disease (IgG4-RD). Methods PD-1+CXCR5−CD4+ T cells in the blood of patients with IgG4-RD (n = 53), patients with SS (n = 16) and healthy volunteers (n = 34) as controls were analysed by flow cytometry. Correlations between results obtained by flow cytometry and clinical parameters relevant to IgG4-RD were also analysed. Results The percentage and absolute number of PD-1+CXCR5− cells within total CD4+ T cells in IgG4-RD patients were significantly increased compared with those in healthy volunteers. Further analysis showed that there were marked positive correlations of the percentage of PD-1+CXCR5−CD4+ T cells with the serum level of IgG4 and the number of organs involved. Interestingly, granzyme A (GZMA)+ cells were enriched in PD-1+CXCR5−CD4+ T cells, and the percentage and absolute number of GZMA+PD-1+CXCR5−CD4+ T cells were significantly elevated in IgG4-RD patients. Although no obvious change was observed in the percentage of total CD4+ T cells, the percentage and absolute number of PD-1+CXCR5−CD4+ T cells decreased in accordance with a reduction of serum IgG4 level after treatment with glucocorticoids. Conclusion In IgG4-RD, circulating CD4+ T-cell populations were composed of PD-1+CXCR5− cells, and the ratios of these cells were correlated with clinical manifestations of IgG4-RD. Further analysis of GZMA+PD-1+CXCR5−CD4+ T cells might lead to a deeper understanding of the pathogenesis of ectopic lymphoid follicles and the persistent inflammation in IgG4-RD.

Allergic rhinitis (AR), the most common allergic disorder of the airway, is often accompanied by bronchial asthma. However, little is known about the mechanism by which AR advances to AR comorbid with bronchial asthma (AR+Asthma). To determine the pathophysiologic features of AR and AR+Asthma, we examined subsets of follicular helper T (Tfh) cells and regulatory B (Breg) cells in peripheral blood from AR and AR+Asthma patients. The results showed polarization of Tfh2 cells within Tfh cell subsets in both AR and AR+Asthma cases. Interestingly, the %Breg cells in total B cells were decreased in AR cases and, more extensively, in AR+Asthma cases. Moreover, we found significant correlations of fractional exhaled nitric oxide and blood eosinophil levels with the index %Tfh2 cells per %Breg cells. Our findings indicate that relative decrease in Breg cells under the condition of Tfh2 cell skewing is a putative exaggerating factor of AR to bronchial asthma.

Objective The aim was to study the pathological role of lymphocytes with a peripheral T helper-cell-like phenotype (PD-1+CXCR5-CD4+) in IgG4-related disease (IgG4-RD). Methods PD-1+CXCR5-CD4+ T cells in the blood of patients with IgG4-RD (n = 53), patients with SS (n = 16) and healthy volunteers (n = 34) as controls were analysed by flow cytometry. Correlations between results obtained by flow cytometry and clinical parameters relevant to IgG4-RD were also analysed. Results The percentage and absolute number of PD-1+CXCR5- cells within total CD4+ T cells in IgG4-RD patients were significantly increased compared with those in healthy volunteers. Further analysis showed that there were marked positive correlations of the percentage of PD-1+CXCR5-CD4+ T cells with the serum level of IgG4 and the number of organs involved. Interestingly, granzyme A (GZMA)+ cells were enriched in PD-1+CXCR5-CD4+ T cells, and the percentage and absolute number of GZMA+PD-1+CXCR5-CD4+ T cells were significantly elevated in IgG4-RD patients. Although no obvious change was observed in the percentage of total CD4+ T cells, the percentage and absolute number of PD-1+CXCR5-CD4+ T cells decreased in accordance with a reduction of serum IgG4 level after treatment with glucocorticoids. Conclusion In IgG4-RD, circulating CD4+ T-cell populations were composed of PD-1+CXCR5- cells, and the ratios of these cells were correlated with clinical manifestations of IgG4-RD. Further analysis of GZMA+PD-1+CXCR5-CD4+ T cells might lead to a deeper understanding of the pathogenesis of ectopic lymphoid follicles and the persistent inflammation in IgG4-RD.

Smoking may have multifactorial effects on asthma phenotypes, particularly in severe asthma. Cluster analysis has been applied to explore novel phenotypes, which are not based on any a priori hypotheses.To explore novel severe asthma phenotypes by cluster analysis when including smoking patients with asthma.We recruited a total of 127 subjects with severe asthma, including 59 current or ex-smokers, from our university hospital and its 29 affiliated hospitals/pulmonary clinics. Clinical variables obtained during a 2-day hospital stay were used for cluster analysis. After clustering using clinical variables, the sputum levels of 14 molecules were measured to biologically characterize the clinical clusters.Five clinical clusters, including two characterized by low forced expiratory volume in 1 second/forced vital capacity, were identified. When characteristics of smoking subjects in these two clusters were compared, there were marked differences between the two groups: one had high levels of circulating eosinophils, high immunoglobulin E levels, and a high sinus score, and the other was characterized by low levels of the same parameters. Sputum analysis revealed intriguing differences of cytokine/chemokine pattern in these two groups. The other three clusters were similar to those previously reported: young onset/atopic, nonsmoker/less eosinophilic, and female/obese. Key clinical variables were confirmed to be stable and consistent 3 years later.This study reveals two distinct phenotypes with potentially different biological pathways contributing to fixed airflow limitation in cigarette smokers with severe asthma.

IgG4-related disease (IgG4-RD) is a newly recognized systemic chronic fibroinflammatory disease. However, the pathogenesis of IgG4-RD remains unknown. To determine the pathophysiologic features of IgG4-RD, we examined T follicular helper (Tfh) cells in lesions and blood from patients with IgG4-RD. Patients with IgG4-related dacryoadenitis and sialadenitis (IgG4-DS) showed increased infiltration of Tfh cells highly expressing programmed death 1 and ICOS in submandibular glands. Tfh cells from IgG4-DS submandibular glands had higher expression of B cell lymphoma 6 and a greater capacity to help B cells produce IgG4 than did tonsillar Tfh cells. We also found that the percentage of programmed death 1hi circulating Tfh cells in IgG4-DS patients was higher than that in healthy volunteers and was well correlated with clinical parameters. Our findings indicate that anomalous Tfh cells in tissue lesions of IgG4-RD have features distinct from those in lymphoid counterparts or blood and potentially regulate local IgG4 production in IgG4-RD.

To date, two studies have reported lower total serum immunoglobulin E (IgE) levels and lower prevalence of atopy in patients with sarcoidosis compared with healthy subjects. However, those reports did not consider age or gender differences between cases and controls. In addition, the association between total serum IgE levels and clinical manifestations of sarcoidosis has not been clarified. This study assessed total serum IgE levels and prevalence of atopy in patients with sarcoidosis after taking age and sex differences into account and evaluated associations between total serum IgE levels and clinical manifestations of sarcoidosis. Total serum IgE levels and prevalence of atopy on initial visits were compared between 189 patients with sarcoidosis and 378 age- and sex-matched controls. Associations between total serum IgE levels and involvement of each affected organ were evaluated. Changes in total serum IgE levels during the clinical course of sarcoidosis were also evaluated. Total serum IgE levels were significantly lower in patients with sarcoidosis than in controls, independent of atopic status (atopic subjects, p = 0.025; nonatopic subjects, p < 0.001). Total serum IgE levels did not differ according to the involvement of different organs. Total serum IgE levels decreased further, albeit only slightly, after disease remission (p < 0.001). Increased susceptibility to sarcoidosis may be attributable to several underlying genetic or environmental factors that result in lower total serum IgE levels.

Sarcoidosis is a systemic chronic granulomatous disease of unknown cause. Recent investigations revealed that the cytokine profile in inflamed lesions of sarcoidosis is Th1 dominant. To obtain better immunopathologic understanding of sarcoidosis, we examined the expression of IL-12 and IL-18 and their roles in IFN-γ production in pulmonary sarcoidosis. Sarcoid cases had significantly elevated levels of IL-12 (p40 and p70) and IL-18 in bronchoalveolar lavage (BAL) fluids compared with healthy subjects. IL-12 p70 and IL-18 were immunohistochemically expressed in the epithelioid cells and giant cells of sarcoid granulomas. Significant induction of IFN-γ, IL-12 p70, and IL-18 was observed from sarcoid BAL fluid cells with LPS stimulation, whereas LPS tended to induce only IL-12 p70 in BAL fluid cells from healthy subjects. Sarcoid cases had significantly greater IFN-γ induction with LPS stimulation than healthy subjects did. IL-18 mRNA expression was observed in freshly isolated sarcoid BAL fluid cells as well as in LPS-stimulated sarcoid BAL fluid cells, but IFN-γ and IL-12 mRNA expression was observed only in LPS-stimulated BAL fluid cells. Treatment with anti-IL-12- and anti-IL-18-neutralizing Abs significantly inhibited IFN-γ production from LPS-stimulated BAL fluid cells of sarcoid cases. Coadministration of rIL-12 or rIL-18 induced greater IFN-γ production in sarcoid BAL fluid cells than in normal BAL fluid cells. We concluded that bioactive IL-12 and IL-18 were produced in sarcoid BAL fluid cells and synergistically induced IFN-γ production, indicating important cytokines in the Th1 response of sarcoidosis.

sICAM-1 has been elevated in sera of specific inflammatory diseases, and circulating sICAM-1 concentrations reflect disease activity in these diseases. We measured circulating sICAM-1 concentrations and serum angiotensin-converting enzyme (SACE) activity in patients with sarcoidosis. Patients with sarcoidosis had significantly increased circulating sICAM-1 concentrations (62.8±33.5U/ml) and SACE activity (23.7±7.4U/l) compared with controls (circulating sICAM-1 50.9±12.1U/ml, and SACE 13.5±3.8U/l). Successive measurements showed that circulating sICAM-1 values changed in parallel with disease activity in sarcoidosis. In the progressive disease group (progressed or without change for 2 years or more), circulating sICAM-1 values (102.2±35.3U/ml) at the time of diagnosis were significantly increased compared with those in the regressive disease group (disappeared or regressed within 2 years) (46.4±12.6U/ml). However, there was no significant difference in SACE activity of the regressive and progressive disease groups. Fifteen patients with a high value of circulating sICAM-1 (>75U/ml, mean of controls+2s.d.) all had progressive disease, while only 15 of 44 patients with a high value of SACE had progressive disease. Circulating sICAM-1 will be a useful blood marker to predict outcome and to monitor disease activity in sarcoidosis.

SUMMARY ICAM-1 plays AN important role in inflammatory diseases. We analysed ICAM-1 expression on BAL fluid cells and measured soluble ICAM-1 (sICAM-l) concentrations in sera and BAL fluids from patients with extrinsic allergic alveolitis (EAA). We found significantly increased cellular ICAM-1 expression on BAL fluid lymphocytes and alveolar marcrophages, and significantly increased values of circulating and BAL fluid sICAM-l in EAA patients compared with controls. Successive measurement showed prompt decrease of both sICAM-1 values in EAA patients during periods when antigen exposure was prevented. In BAL fluids from EAA patients. sICAM-l values significantly correlated to neutrophil and ICAM-1+ lymphocyte counts. In EAA patients, circulating and BAL fluid sICAM-l values has significant negative correlations to values of carbon monoxide diffusing capacity and to time intervals between last episode and sample collection. However, these values had significant positive correlation to values of alveolar-arterial oxygen pressure difference. In EAA, antigen exposure appears to induce cellular ICAM-1 expression on BAL fluid cells, and also appears to up-regulate shedding of ICAM-1 in the alveolar lining fluid and in the circulation. The sICAM values appear to reflect disease activity of EAA.

We investigated phenotypic surface markers of peripheral blood lymphocytes including expression of γδ T cell receptor (TCRγδ) in 185 patients with sarcoidosis and 42 normal subjects. The pr

We measured eosinophilic cationic protein (ECP) concentrations in the circulation and bronchoalveolar lavage (BAL) fluids from patients with chronic eosinophilic pneumonia, patients with eosinophilic granuloma, and normal control subjects. Significantly increased ECP concentrations were found in the circulation of patients with chronic eosinophilic pneumonia and with eosinophilic granuloma compared with those found in control subjects. The ECP concentrations were well correlated to eosinophil counts in the circulation of patients with chronic eosinophilic pneumonia, while they were not in patients with eosinophilic granuloma. Chronic eosinophilic pneumonia patients had prominently increased ECP concentrations in BAL fluids compared with those found in control subjects, while eosinophilic granuloma patients did not. Those concentrations in chronic eosinophilic pneumonia patients were well correlated to eosinophil counts in the BAL fluid. Corticosteroid therapy remarkably decreased circulating ECP concentrations in three patients with chronic eosinophilic pneumonia, but it had no significant effects in two patients with eosinophilic granuloma. Measurement of ECP concentrations seems to be useful to evaluate the disease activity of chronic eosinophilic pneumonia.

SUMMARYICAM-1 plays an important role in inflammatory diseases. To assess level of soluble ICAM-1 in the circulation and inflamed lesions, we measured levels of soluble ICAM-1 in the circulation and bronchial veolar lavage fluid (BALF) of patients with idiopathic pulmonary fibrosis (IPF) and with pulmonary sarcoidosis (PS) and of healthy volunteers (HV), and we also analysed ICAM-I expression of BALF cells in some patients and HV. IPF patients had significantly higher levels of circulating ICAM-1 than HV, while PS patients did not. By contrast, significantly increased levels of BALF soluble ICAM-1 were found in PS patients compared with those of HV, but not in IPF patients. There were no significant differences in the proportions of ICAM-1+ BALF lymphocytes in IPF patients, PS patients and HV. whereas significantly increased proportions of ICAM-1 pulmonary alveolar macrophages were found in PS patients compared with those of HV, but not in IPF patients. There was a significant positive correlation of BALF soluble ICAM-1 levels to BALF lymphocyte proportions in PS patients. Although the source of BALF soluble ICAM-1 is unclear. BALF soluble ICAM-1 appears to reflect the grade of local activity of sarcoidosis. An interesting discrepancy between soluble ICAM-1 levels in the circulation and BALF was found in IPF patients, and this might be an important clue to an understanding of this disorder.

Allergic rhinitis (AR) is the most common allergic inflammatory disorder of the airway and its increasing worldwide prevalence has made it a global health problem. AR frequently precedes bronchial asthma (in 10 to 40% of cases), and the presence of AR is considered to be a risk factor for new onset of asthma. However, little is known about the mechanism by which AR advances to a state of AR with bronchial asthma (AR+Asthma). To determine the pathophysiologic features of AR and AR+Asthma, we examined subsets of follicular helper T (Tfh) cells and regulatory B (Breg) cells in peripheral blood from AR and AR+Asthma patients. The results demonstrated polarization of Tfh2 cells within Tfh cell subsets in both AR and AR+Asthma cases. Interestingly, Breg cells were decreased in AR cases and, more extensively, in AR+Asthma cases. Addtionally, we found significant correlations of fractional exhaled nitric oxide and blood eosinophil levels with the index %Tfh2 cells per %Breg cells. Our findings indicate that depletion of Breg cells under the condition of Tfh2 cell skewing is a putative exaggerating factor of AR to bronchial asthma.

In rheumatoid arthritis (RA) patients treated with infliximab (IFX), QuantiFERON-TB Gold (QFT-G), an interferon gamma assay for diagnosing tuberculosis infection, was performed to compare its effectiveness to conventional diagnostic procedures (tuberculin skin test, imaging and medical history) in diagnosing latent tuberculosis infection (LTBI). QFT-G was measured bimonthly in 14 rheumatoid arthritis patients during IFX treatment. Seven of 14 patients were confirmed as LTBI positive by at least one method. Of these, four were positive on QFT-G during the study period, and two were positive before the start of IFX administration. For two of the four QFT-G-positive patients, LTBI was diagnosed only by QFT-G. The rate of agreement between QFT-G and conventional procedures was 64.3%. A total of 5% of QFT-G tests were impossible to judge due to decreased reactions in the positive control. These results suggest that QFT-G is able to detect LTBI in RA patients overlooked by conventional methods. Conventional procedures and QFT-G should be employed in parallel, and LTBI should be assumed when one technique gives a positive result.

A female patient with idiopathic interstitial pneumonia (IIP) was admitted again 40 months after the diagnosis due to progression of clinical findings and increased activity of serum lactic dehydrogenase (LDH). Analysis of LDH isoenzyme disclosed a broad band between LDH4 and LDH5. Gel filtration and immunoelectrophoresis showed that immunoglobulin (Ig) G (κ type) bound the LDH. With prednisolone and azathioprine, her symptoms and radiological findings improved concomitant with a decrease in the serum LDH activity. The LDH-IgGκ complex disappeared in the circulation 14 months after initiation of the therapy. We report circulating LDH-Ig complex in a patient with IIP, which may be related to the disease progression of IIP. (Internal Medicine 35: 413-415, 1996)

Sarcoidosis is immunologically characterized by highly enhanced Th1 responses in active stage. TAK-603 is a new quinoline derivative, which selectively suppresses Th1 cytokine production. Thus, the present study was designed to investigate whether TAK-603 ameliorates excess IFN-gamma production in active sarcoidosis.We evaluated inhibitory effects of TAK-603 on IFN-gamma, IL-12 and IL-18 production in stimulated bronchoalveolar lavage (BAL) fluid cells and peripheral blood mononuclear cells (PBMCs) of sarcoidosis patients and healthy subjects.TAK-603 inhibited IFN-gamma production in stimulated BAL fluid cells and PBMCs of sarcoidosis patients and healthy subjects. TAK-603 inhibited IL-12 production in stimulated BAL fluid cells of sarcoidosis patients and healthy subjects. TAK-603 tended to inhibit IL-12 production in stimulated PBMCs of sarcoidosis patients and healthy subjects. However, TAK-603 did not affect IL-18 production in stimulated BAL fluid cells and PBMCs. TAK-603 did not affect TNF-alpha production in stimulated BAL fluid cells of sarcoidosis patients. TAK-603 inhibited IL-12 production in stimulated blood monocytes of healthy subjects, whereas IL-18 was increased by treatment with TAK-603. TAK-603 inhibited IFN-gamma production in PHA-stimulated blood T lymphocytes of healthy subjects with stimulation of IL-12 or a combination of IL-12 and IL-18. TAK-603 did not increase IL-10 or TGF-beta1 production in LPS-stimulated BAL fluid cells of sarcoidosis patients.TAK-603 inhibits IFN-gamma production in activated T lymphocytes and IL-12 production in activated monocytes/macrophages independently of increased production of IL-10 and TGF-beta1. TAK-603 may ameliorate excess IFN-gamma production and be a therapeutic tool for refractory sarcoidosis.

SUMMARYIn sarcoidosis, a T helper 1 (Th1) response is an essential event and the up-regulation of interleukin-12 (IL-12) has been detected in affected disease sites. In order to investigate the clinical usefulness of circulating IL-12, we measured the serum concentrations of IL-12 by ELISA and performed immunohistochemistry using specific MoAbs for IL-12 in the lungs and scalene lymph nodes of patients with sarcoidosis. The serum concentration of IL-12 p40 was detectable in all 45 patients with pulmonary sarcoidosis and 18 normal controls, whereas that of IL-12 p70 was undetectable. The serum concentrations of IL-12 p40 in pulmonary sarcoidosis were significantly higher than those of the normal controls, especially in cases with abnormal intrathoracic findings detected by chest roentogenogram. The serum concentrations of interferon-γ (IFN-γ) also increased compared with those of normal controls and there was a significant positive correlation between the serum concentrations of IL-12 p40 and IFN-γ. Furthermore, serum angiotensin-converting enzyme (ACE) and lysozyme, which are known to be useful markers for disease activity in sarcoidosis, correlated well with the serum concentrations of IL-12 p40. The positive 67Ga scan group (for lung field) had significantly elevated serum IL-12 p40 levels compared with those of the negative group. No bioactivity of IL-12 p70 was detected in three sarcoid cases sera by using the IL-12 responsive cell line. Finally, the immunohistochemical approach revealed that IL-12 p40 was expressed in the epithelioid cells and macrophages of sarcoid lungs and lymph nodes. We concluded that the production of IL-12 p40 was far greater in the sera and we have demonstrated this to be a useful clinical marker for disease activity and the Th1 response in pulmonary sarcoidosis.

Interleukin-18 (IL-18) has recently been identified as an interferon-gamma (IFN-gamma)-inducing factor, and it plays an important role in T helper 1 (Th1) response. We measured the serum levels of IL-18 and IFN- gamma in 37 patients with pulmonary sarcoidosis and 25 healthy control subjects. We also measured the levels of IL-18 and IFN-gamma in 10-fold concentrated bronchoalveolar lavage (BAL) fluids of 19 patients with pulmonary sarcoidosis and 9 healthy control subjects (all lifelong nonsmokers). The levels of serum IL-18 and IFN-gamma were significantly increased in patients with sarcoidosis. The levels of BAL fluid IL-18 were significantly elevated in patients with sarcoidosis, however, the IFN-gamma levels of the patients and control subjects were all below sensitivity. Serum IL-18 levels significantly correlated with serum IFN-gamma levels and lysozyme activity. The patients positive for gallium-67 ((67)Ga) scan had significantly elevated serum IL-18 levels as compared with those of the negative patients. BAL fluid IL-18 levels significantly correlated with serum IL-18 levels in patients with sarcoidosis, and there was a significant correlation between IL-18 levels and lymphocyte proportions in sarcoid BAL fluids. In patients with sarcoidosis, IL-18 seems to induce IFN-gamma production and IL-18 levels in sera may reflect disease activity of sarcoidosis.

Interleukin-18 (IL-18) has recently been identified as an interferon- gamma-inducing factor and it plays an important role in the Th1 response. We measured serum levels of IL-18 and interferon-gamma (IFN-gamma) in 43 patients with pulmonary tuberculosis and 25 healthy control subjects. Significantly increased levels of circulating IL-18 and IFN-gamma were found in pulmonary tuberculosis as compared with those in healthy control subjects. Circulating IL-18 and IFN-gamma correlated with the extent of disease in pulmonary tuberculosis. We found significantly increased levels of circulating IL-18 and IFN-gamma in the patients with high-grade fever. Circulating IL-18 significantly correlated with circulating IFN-gamma. IL-18 may play an important role in immune response to human infection with Mycobacterium tuberculosis.

Fungal infections are often reported, but Trichosporon infection is very rare. A 78-year-old man with adult T-cell leukemia complicated with pulmonary infections is presented. Bronchial exudate culture revealed many yeast-like colonies, which were morphologically and biochemically identified as Trichosporon pullulans.

To improve our understanding of the role of extracellular matrix (ECM) proteins and integrins during the processes of granuloma formation in sarcoidosis, we examined the distribution of ECM proteins and the expression of integrins in sarcoid lymph nodes by immunohistochemical methods. We also examined the expression of transforming growth factor-beta1 (TGF-beta1), which is one of major regulators for synthesis of ECM proteins. Most ECM proteins were detected in the periphery of the granulomas in a concentric pattern, and fibronectin was diffusely detected from an early to a regressive stage. Compared with normal lymph nodes, most beta1-integrin subfamilies (alpha1, alpha4, alpha5 and alpha6) were more strongly expressed on lymphocytes around the granulomas. Epithelioid cells exhibited strong expression of the alpha5 molecule. Fibroblasts exhibited the expression of the alpha2 and alpha5 molecules surrounding ECM proteins. The alpha5beta1 molecule had a distribution similar to that of fibronectin. TGF-beta1 was detected in epithelioid cells throughout the various evolutional stages and its expression was especially marked in mature granulomas. Interaction of fibronectin and the alpha5beta1 molecule may have an important role in the process of formation of sarcoid granuloma. The expression of TGF-beta1 may be involved in the regression of sarcoid granuloma by initiating fibrosis and atrophy of epithelioid cells.

A patient with eosinophilic granuloma, histologically confirmed from open lung biopsy specimen, had a history of scarlet fever and a prominently high level of circulating gamma/delta T cells (25 percent) in comparison with normal levels (10 percent). Despite steroid therapy, the levels were persistently high. To our knowledge, this is the first report of an increased level of circulating gamma/delta T cells in a patient with eosinophilic granuloma.

Sarcoidosis is a systemic granulomatous disorder with a high rate of spontaneous regression. Clara cell 10-kDa protein (CC10), the predominant product of nonciliated bronchiolar epithelial cells, is a potent immunoregulatory and anti-inflammatory agent. CC10 levels were measured in sera and bronchoalveolar lavage (BAL) fluids from 31 sarcoidosis patients (nine progressive disease and 22 regressive disease) and their relevance to spontaneous regression investigated. The inhibitory effects of recombinant CC10 on interferon gamma (IFN-gamma) production were examined using lipopolysaccharide (LPS)-stimulated sarcoid BAL fluid cells, and the blocking effects of monoclonal antibody TY-5, directed against CC10, on CC10 function were also tested. Serum and BAL fluid CC10 levels in the regressive disease group were significantly higher than those in the progressive disease group (serum, p