Clinical significance of elevated soluble interleukin-6 receptor levels in the sera of patients with plasma cell dyscrasias

Summary .We investigated the clinical significance of the serum soluble interleukin-6 receptor (sIL-6R) in 42 patients with plasma cell dyscrasias (27 with multiple myeloma (MM), 13 with monoclonal gammopathy of undetermined significance (MGUS), and two with plasma cell leukaemia (PCL)). Serum levels of sIL-6R in normal individuals were 77 ± 21 ng/ml (mean ± SD, n = 18); those in patients with MGUS and with MM were elevated (102 ± 33 ng/ml, mean ± SD, P < 0–05 and 126 ± 60ng/ml, mean ± SD, P < 0–01, respectively). Significant correlations were not found between the serum levels of sIL-6R and known prognostic factors (C-reactive protein, haemoglobin levels, calcium, creatinine, β₂-microglobulin, amounts of M-protein, or percentages of plasma cells in bone marrow). Elevated serum sIL-6R did not affect the survival of the patients with MM. Serial measurements of sIL-6R together with the clinical course of patients with plasma cell neoplasias revealed a good correlation between the sIL-6R level and disease activity. We conclude that sIL-6R can be used as a clinical factor correlated with the disease activity, at least in some patients with plasma cell neoplasias.     

Soluble interleukin-6 receptor (sIL-6R), a new prognostic factor in multiple myeloma

sIL-6R is a 55 kD soluble molecule mediating the interleukin-6 (IL-6) signal through the IL-6 receptor-associated transmembrane signal transducer, gp130. It has recently been suggested that sIL-6R serum levels may reflect disease severity in multiple myeloma (MM). We determined sIL-6R serum levels in 25 normal controls (NC) and in 80 MM patients at diagnosis and during the course of the disease. Measurements were done by ELISA. In NC, sIL-6R levels ranged from 14 to 40 ng/ml (median 28 ng/ml) whereas in MM patients the range was 10–200 ng/ml (median 38 ng/ml) ( P  < 0.01). 61 patients entered remission and 19 were resistant. Median sIL-6R value at diagnosis was 36 ng/ml (10–120) in responding patients, and 82 ng/ml (20–200) in non-responding patients ( P  < 0.001). During a follow-up from 12 to 89 months, sIL-6R values remained more or less stable in most patients. High sIL-6R levels correlated with poor survival.     

Serum immunoreactive interleukin-6 and C-reactive protein levels in patients with multiple myeloma at diagnosis

Summary Serum bioactive but not immunoreactive interleukin-6 (IL-6), and serum C-reactive protein (CRP), have been reported to be of prognostic significance in multiple myeloma (MM). We measured serum immunoreactive IL-6 by a sensitive enzyme-linked immunosorbent assay in 30 MM patients at diagnosis. In 30% of the patients serum immuno-reactive IL-6 exceeded the upper reference limit. The concentrations of CRP and IL-6 showed a linear association. Logarithmically transformed IL-6, CRP and β₂-microglobulin were significant variables by univariate survival analysis: by multivariate analysis CRP was a slightly stronger prognostic factor than IL-6 and the only one of independent prognostic significance.     

Human myeloma cells shed the interleukin-6 receptor: inhibition by tissue inhibitor of metalloproteinase-3 and a hydroxamate-based metalloproteinase inhibitor

Interleukin-6 (IL-6) is the major growth factor for human myeloma cells, exerting its effect through the IL-6 receptor (IL-6R). A soluble form of IL-6R (sIL-6R) has been identified, which increases the sensitivity of myeloma cells to IL-6. In patients with multiple myeloma (MM), serum concentrations of sIL-6R are elevated and associated with poor prognosis. The present study was undertaken to determine whether proteolytic cleavage of IL-6R could contribute to sIL-6R release from human myeloma cells, and also to identify the class of proteinase responsible for this event. Human myeloma cell lines were shown to express IL-6R upon their surface and also to release sIL-6R into culture supernatants. In addition, phorbol 12-myristate 13-acetate (PMA) stimulated a loss of IL-6R from the cell surface, with a corresponding increase in the concentration of sIL-6R in the supernatant. Inhibitors of serine and cysteine proteinases, and tissue inhibitor of metalloproteinase (TIMP) -1 and TIMP-2, were shown to have no effect on the magnitude of sIL-6R release. In contrast, TIMP-3 and a hydroxamate-based metalloproteinase inhibitor (BB-94), inhibited both constitutive and PMA-induced release of sIL-6R. Myeloma cells freshly isolated from the bone marrow of a patient with MM were also shown to express IL-6R upon their surface, and to shed this receptor in response to PMA. These data demonstrate that increased proteolytic cleavage of IL-6R, mediated by a non-matrix-type metalloproteinase, is likely to contribute to the elevated concentrations of sIL-6R found in the serum of patients with MM. Inhibition of sIL-6R release by hydroxamate-based metalloproteinase inhibitors may represent a novel therapeutic approach to the treatment of MM.     

Prognostic value of serum IL-10 and soluble IL-2 receptor levels in aggressive non-Hodgkin's lymphoma

Summary We investigated the prognostic significance of interleukin-10 (IL-10) and soluble interleuckin-2 receptor (sIl-2r) levles in the pretreatment serum of 105 individuals with newly-diagnosed aggressive non-Hodgkin's lymphoma (NHL). Commercially available enzyem-linked immunoassay kits were used for cytokine and receptor measurements. Detectable levels of IL-10 were found in 42 (40%) patients at diagnosis, with no correlation with clinico-haematological parameters, but in no control samples (P < 0.001).
Pretreatment concentrations of sIL-2r were markedly increased in individuals with NHL when compared to controls (2614 ± 893 U/ml v 219 ± 65U/ml, P < 0.001), patients with stage III/IV presenting higher values than those with stage II disase (3885 ± 1196U/ml v 1732 ± 646U/ml, P < 0.001). No single parameter was associated with the achiveement of complete remission, but the combination of elevated IL-10 and of sIL-2r greater than 3000U/ml selected a subset of patients with a high probability of failing induction therapy (P < 0.001). Lifetable analysis also indicated thatj patients with these characteristics have a significantly shorter event-free survival. In a multivariate analysis the combination of IL-10 with sIL-2r was found to have greater predictive strength than the combination of IL-10 with β₂-micro-globulin. We conclude that IL-10 and sIL-2r measurements can be expected to improve existing methods of risk assignment in aggressive NHL.     

Immunoreactive interleukin-6 and acute phase proteins as prognostic factors in multiple myeloma. Finnish Leukemia Group

High serum level of bioactive interleukin-6 (IL-6) is regarded as a predictor of poor prognosis in multiple myeloma (MM). On the other hand, the reported levels of immunoreactive IL-6 have been highly variable, and the prognostic value of immunoreactive IL-6 in MM is not clear. We have analyzed the prognostic significance of serum immunoreactive IL-6, as measured by a sensitive immunosorbent assay, in 210 patients with newly diagnosed MM subsequently treated with intermittent melphalan and prednisone. The serum levels of acute phase proteins C-reactive protein (CRP), alpha 1-antitrypsin (alpha 1AT), and acid alpha 1-glycoprotein (orosomucoid; OM) were evaluated as surrogates for IL-6. Serum IL-6, CRP, alpha 1AT, and OM levels were raised in 42%, 40%, 41%, and 24% of the patients, respectively. There was a significant correlation between the clinical stage of the patients and serum IL-6 (P = .006), alpha 1AT (P = .001), and OM (P = .004) levels at diagnosis. At 3 years, 52% of the patients were alive. Univariate logistic regression analysis showed that high levels of IL-6 (P = .002), CRP (P = .02), alpha 1AT (P < .001), OM (P = .007), beta 2- microglobulin (beta 2M; P < .001), and thymidine kinase (P < .05) were all associated with 3-year mortality. In multivariate regression analysis, beta 2M (P < .0001) and alpha 1AT (P = .01) had independent prognostic significance. The patients with high levels of both beta 2M and alpha 1AT or IL-6 were at very high risk of dying within 3 years from diagnosis (16% and 21% of the patients in these groups were alive, respectively). When the patients were stratified according to the clinical stage, the prognostic significance of serum IL-6 and alpha 1AT was especially evident in stage II patients. When the patients were divided into two groups according to normal or raised serum IL-6 levels, the patients with high IL-6 levels had more frequent osteolytic bone lesions (P = .03) and a more aggressive disease. We conclude that serum immunoreactive IL-6 is a significant prognostic marker in MM.     

Soluble interleukin-6 receptor in rheumatoid arthritis

Abstract

To investigate the pathophysiologic role of soluble interleukin-6 receptor (sIL-6R) in patients with rheumatoid arthritis (RA), serum sIL-6R levels were measured in 15 RA patients and 15 healthy control subjects using a sandwich enzyme-linked immunosorbent assay. Correlation analysis was performed between sIL-6R levels and clinical variables such as joint score, Lansbury’s index, C-reactive protein and platelet counts. Levels of sIL-6R and IL-6 were also measured in paired samples of serum and synovial fluid obtained at the same time from nine RA patients. Serum sIL-6R levels in RA patients (153.9±56.9 ng/ml) were significantly higher than those of control subjects (115.1±19.1 ng/ml; P<0.05). However, sIL-6R levels did not correlate with any clinical characteristic of RA. sIL-6R was detectable in synovial fluid, but was invariably lower than in serum, in contrast to IL-6 (i.e. much higher in synovial fluid). It correlated neither with total cell nor neutrophil number in synovial fluid. Serum C-reactive protein levels were significantly correlated with IL-6 in synovial fluid, but not with sIL-6R in synovial fluid. These results indicate that serum sIL-6R levels are increased in RA patients. High levels of serum sIL-6R did not seem to be derived from the site of local inflammation. The readily detectable sIL-6R in synovial fluid may co-operate with IL-6 in the pathogenesis of synovitis in RA.     

Soluble interleukin-6 receptor in rheumatoid arthritis

To investigate the pathophysiologic role of soluble interleukin-6 receptor (sIL-6R) in patients with rheumatoid arthritis (RA), serum sIL-6R levels were measured in 15 RA patients and 15 healthy control subjects using a sandwich enzyme-linked immunosorbent assay. Correlation analysis was performed between sIL-6R levels and clinical variables such as joint score, Lansbury’s index, C-reactive protein and platelet counts. Levels of sIL-6R and IL-6 were also measured in paired samples of serum and synovial fluid obtained at the same time from nine RA patients. Serum sIL-6R levels in RA patients (153.9±56.9 ng/ml) were significantly higher than those of control subjects (115.1±19.1 ng/ml;P<0.05). However, sIL-6R levels did not correlate with any clinical characteristic of RA. sIL-6R was detectable in synovial fluid, but was invariably lower than in serum, in contrast to IL-6 (i.e. much higher in synovial fluid). It correlated neither with total cell nor neutrophil number in synovial fluid. Serum C-reactive protein levels were significantly correlated with IL-6 in synovial fluid, but not with sIL-6R in synovial fluid. These results indicate that serum sIL-6R levels are increased in RA patients. High levels of serum sIL-6R did not seem to be derived from the site of local inflammation. The readily detectable sIL-6R in synovial fluid may co-operate with IL-6 in the pathogenesis of synovitis in RA.     

狼疮性肾炎患者血清IL-6和sIL-2R水平变化的检测

目的探讨狼疮性肾炎(LN)患者血清中白细胞介素(IL)-6和可溶性IL-2受体(sIL-2R)的水平变化及临床意义。方法利用酶联免疫吸附试验(ELISA)检测42例LN患者和40例正常健康人血清IL-6和sIL-2R的水平。结果活动期LN组患者IL-6和sIL-2R水平显著高于静止期LN组患者及正常对照组(P<0.01),静止期LN组患者IL-6和sIL-2R水平显著高于正常对照组,差异有显著性(P<0.01)。结论LN患者血清IL-6和sIL-2R显著升高,可能与LN的发生发展有关,并可作为病情及疗效判断的观察指标。     

Incidence of apoptosis and cell proliferation in multiple myeloma: correlation with bcl-2 protein expression and serum levels of interleukin-6 (IL-6) and soluble IL-6 receptor

We evaluated the in vivo incidence of apoptosis and cell proliferation in multiple myeloma (MM) and investigated the correlation of both cellular events with histological tumour stage and grade, bcl-2 protein expression, serum IL-6 and sIL-6R. MATERIAL AND METHODS: The TUNEL method was used to assess apoptosis and immunohistochemistry to assess the expression of proliferating cell nuclear antigen (PCNA) and bcl-2 protein in 30 bone marrow biopsy specimens. The apoptotic index (AI) and proliferative index (PI) were defined as the percentage of TUNEL and PCNA positive plasma cells, respectively. RESULTS: The mean AI was 0.162% and the mean PI 27.44%. A positive correlation between AI and PI was found (r = 0.44, P = 0.017). PI was also correlated with tumour grade (P = 0.015). The mean bcl-2 protein expression was 70% and did not correlate with AI or PI, but was higher in specimens taken at first diagnosis than in specimens taken after response to treatment (P = 0.035). The mean serum IL-6 and sIL-6R values were 9.43 pg mL-1 and 47.27 ng mL-1, respectively. These parameters did not correlate with AI or PI. CONCLUSIONS: The results indicate that MM might be among the malignancies with very low incidence of apoptosis. Proliferative activity increased in parallel with tumour histological grade. A positive correlation between apoptosis and proliferation was observed, but the incidence of these two cellular events seems not to be related to the bcl-2 protein expression and the serum levels of IL-6 and sIL-6R.     

High level of soluble interleukin-2 receptor in serum predicts treatment resistance and poor progression-free survival in multiple myeloma

The IL-2/IL-2 receptor (IL-2R) system plays a central role in maintaining normal T cell immunity, and its disturbance is associated with several hematologic disorders. Studies have found in several types of lymphoma that abnormal amounts of soluble IL-2R (sIL-2R) may result in imbalance of the IL-2/IL-2R system and hence of the T cell immunoregulation. Whether the level of sIL-2R in blood could predict treatment outcomes or not needs to be investigated in multiple myeloma (MM) patients. The level of sIL-2R in serum was measured using enzyme-linked immunosorbent assay (ELISA) in 81 patients with newly diagnosed MM. Twenty-six patients (32.1%) were treated with bortezomib-based regimens and 55patients (67.9%) received old drugs-based regimens. The mean concentration of sIL-2R for myeloma patients was 8.51 ng/ml, significantly higher than that of healthy controls (0.56 ng/ml, p < 0.0001). The best cutoff value for sIL-2R in predicting high risk for disease progression is 6.049 ng/ml with an area under curve (AUC) of 0.665 (p = 0.013). Thirty-six patients (44.4%) were classified as higher sIL-2R level group (> 6.049 ng/ml), and 45 patients (55.6%) as lower group (≤ 6.049 ng/ml). The overall response rate (ORR) was 60.0% in lower sIL-2R level group, and 41.7% in higher level group (p = 0.156). The median progression-free survival (PFS) and overall survival (OS) was 12 months (range, 2.0–65 months) and 20 months (range, 2.0–118 months), respectively. In a multivariate survival analysis, including Eastern Cooperative Oncology Group performance status score, treatment response, and sIL-2R level, it was found that all these three parameters were significantly independent prognostic factors for PFS (p = 0.032, 0.016, and 0.043, respectively), but none factors maintained their value in predicting OS. Subgroup analysis revealed that high level of sIL-2R is correlated with significantly inferior PFS in patients treated with bortezomib-based regimens (p = 0.004). Serum sIL-2R level is an independent prognostic factor for PFS, indicating novel drugs targeting the imbalance of IL-2/IL-2R system may be a promising strategy in MM.     

老年深静脉血栓形成和转归中炎症因子的作用研究

目的 研究白细胞介素家族中的有关炎症反应因子和C-反应蛋白（CRP）在老年深静脉血栓（DVT）病人中的作用及其发病机理,探讨老年DVT病人的早期诊断和病程转归标志物。方法 选39例老年急性DVT病人。在治疗前2h和治疗后第1、3、7、14天,分别检测IL-2、sIL-2R、IL-4、IL-6、IL-8和CRP。结果 在急性DVT病人中sIL-2R、IL-6、IL-8和CRP在治疗前2h和治疗后第1天高于正常值（P〈0,01）,该两个阶段之间差异无统计学意义（P〉0．05）,与治疗后第3天,第7天和第14天差异有统计学意义（P〈0．01）,IL-2在治疗前后呈现下降趋势（P〈0．01）,IL-4治疗前后差异无统计学意义（P〉0．05）。结论 IL-2、sIL-2R、IL-6、IL-8和CRP,可作为老年DVT病人血液中早期炎症标志物的测定,也可以作为反映和病情转归的炎症标志物测定。     

Comparison of serum IL-1β, sIL-2R,IL-6, and TNF-α levels with disease activity parameters in ankylosing spondylitis

Ankylosing spondylitis (AS) is a chronic, inflammatory, rheumatological disease affecting primarily the sacroiliac joint and vertebral column, with an etiology that remains obscure. Cytokines are soluble proteins that have specific roles in inflammatory response, arranging the interaction between cells of the immune system both in natural and specific immune reactions. This study was planned to evaluate the relation between the level of cytokines and the clinical and laboratory findings of patients with AS compared to healthy subjects. In this study, we demonstrated increased serum levels of soluble interleukin-2 receptor (sIL-2R), Interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in patients with AS compared with healthy subjects. Only IL-1β levels were not increased in AS patients. We found a correlation between C-reactive protein and IL-6 levels and between erythrocyte sedimentation rate and sIL-2R, IL-6 and TNF-α levels. Only the sIL-2R level was correlated with Bath AS Metrology Index and Bath AS Functional Index. We suggest that sIL-2R, IL-6, and TNF-α may have a role in the pathogenesis of AS and that their serum levels can be used as disease activity parameters and tools for diagnosis.     

Prognostic evaluation in multiple myeloma: an analysis of the impact of new prognostic factors

We have analysed the prognostic information for survival of presenting features in an unselected series of 394 myeloma patients. 15 variables with significant prognostic information were identified, among these were some not previously or only recently reported: serum levels of hepatocyte growth factor (HGF), interleukin-6 (IL-6), C-terminal cross-linked telopeptide of collagen I (ICTP) and soluble interleukin-6 receptor (sIL-6R). In a multivariate Cox analysis six variables were significantly and independently associated with poor survival: high age, low W.H.O.-performance status (PS), high serum levels of calcium, beta-2-microglobulin (beta-2M), IL-6 and sIL-6R. A risk score formed to predict survival for each percentile of the patient population allowed an efficient separation of prognostic groups. The discriminating power of the model compared favourably with three other previously published staging systems applied to the study population. Exclusion of IL-6 and sIL-6R from the model only marginally decreased the efficacy of the separation. The predictive value of some variables (sIL-6R, beta-2M and W.H.O.-PS) decreased significantly over time. We conclude that formation of a risk score based on independent variables is an efficient way to separate prognostic groups, that the contribution of new and not easily available parameters should be thoroughly evaluated before inclusion in prognostic models for clinical use and that the predictive value of parameters may decrease over time.     

Serum interleukin-6 has no discriminatory role in paraproteinaemia nor a prognostic role in multiple myeloma.

We determined interleukin-6 (IL-6) levels in the serum of 212 well-defined patients with newly diagnosed paraproteinaemia and evaluated its discriminatory value and prognostic role in multiple myeloma (MM). Results were compared with serum neural cell adhesion molecule and beta-2-microglobulin, both established prognostic MM markers. Paraproteinaemia-related diagnoses were: MM (60), other haematological diseases (46), solid tumours (35), autoimmune diseases (17) and monoclonal gammopathy of unknown significance (MGUS) (54). The range of IL-6 levels in all diagnostic groups overlapped widely and did not serve as a discriminatory marker in newly diagnosed paraproteinaemia even when patients with infection or fever (42) were excluded. In MM high IL-6 levels (>/= 50 pg/ml) were not associated with a shorter survival (P = 0.24). We compared our results with 20 published studies on serum IL-6 in paraproteinaemia and/or MM. IL-6 data have to be related to the assay used (bio- or immunoassay) and to the status of MM (newly diagnosed, during therapy, progressive disease). We conclude that serum IL-6 is not specific for paraproteinaemia-related diseases and will not serve as a reliable discriminatory or prognostic marker in paraproteinaemia and MM.     

Changes of IL-6 and relevant cytokines in patients with hepatocellularcarcinoma and their clinical significance

AIM To study the changes of IL-6,IL-2, sIL-2R and TNF ir patients with hepatocellular carcinoma(HCC)and their clinical significance.METHODS IL-6, IL-2, sIL-2R and TNF were detected by avidin-biotin-system ELISA, double-sandwichELISA respectively in 60 patients with HCC and 36 patients with liver cirrhosis (LC) and 66 healthy persons.RESULTS The levels of IL-6, sIL-2R and TNF increased, but IL-2 level was lower in patients with HCCthan that in normal controls (NC) (t test, t=8.21, 4.71, 3.87, 2.13, P<0.01 or 0.05). IL-6 level in HCCwas 10 fold higher than NC, and also much higher than LC. IL-6 level was higher in later stage than that inearlier stage. There was a positive correlation between IL-6 and sIL-2R, TNF, while no positive correlationwas found between IL-2 and IL-6, sIL-2R in HCC.CONCLUSION The remarkably higher level of IL-6 is helpful for the early diagnosis of HCC.     

Hyper-interleukin (IL)-6-naemia in haemophagocytic lymphohistiocytosis

Clinical features in patients with haemophagocytic lymphohistiocytosis (HLH) have been demonstrated to be characterized by hypercytokinaemia. Previously, we reported the impact of high serum levels of interferon (IFN)-gamma and soluble IL-2 receptor (sIL-2R) on patient outcome; however, it was not known if serum levels of interleukin (IL)-6 also could be a prognostic factor. In a study during the active phase of disease in 25 cases of HLH in children and young adults (median age 3 years, range 0.1–23 years), we noted 12 cases which showed serum IL-6 >100 (normal <4.0) pg/ml. Five of these cases showed hyper-IL-6-naemia alone without hyper-IFN-gamma-naemia (group A) whereas seven cases showed both hyper-IL-6- and IFN-gamma-naemia (group B). Patient outcome did not differ between the patients with IL-6 >100 pg/ml and those with IL-6 <100 pg/ml, suggesting that high serum concentrations of IL-6 alone do not necessarily indicate poor prognosis in patients with HLH. Among the cases with hyper-IL-6-naemia (>100 pg/ml), underlying disorders causing haemophagocytosis were found to be different between groups A and B.     

Malignancy: Identification of Predictors of Disease Status and Progression in Patients with Myeloma (MM)

Multiple studies have attempted to recognize the best markers of disease activity and outcome in myeloma (MM). Our objective was to identify the best variables that can reflect MM disease status. Design and methods: The data obtained from all the following tests were included in the analysis: serum levels of the 2 growth factors known to be crucial for MM growth (i.e. IL-6, and sIL-6R), routine peripheral blood data (Hb%, serum calcium, albumin, CRP, B2m, LDH) and bone marrow plasma cell (BMPC)%, as well as the age and sex of patients. The study was conducted on 21 cases of MM under chemotherapy (aged 48-74 years; M/F = 13/8) and 12 matched normal individuals. The patients were categorized into 2 groups according to their clinical status: Group#1 (n = 16; cases in plateau/stable phase), and Group#2 (n = 5; advanced/refractory cases). Results: Student t-test confirms that serum IL-6 and sIL-6R are the most statistically different variables upon comparing cases in plateau phase (Group#1) with those of advanced disease (Group#2). Stepwise discriminant analysis of data has resulted in a function that is composed of the 2 most salient variables (i.e. serum IL-6, sIL-6R). The proposed function was highly significant (p = 0.0000) with Wilk's Lambda = 0.02538. The diagnostic capability of the proposed function was very high (percent of grouped cases that were classified correctly= 100%). Conclusion: measurement of serum IL-6 and sIL-6R gives the best prediction of disease activity in patients with MM.     

Serum levels of soluble interleukin-2 receptors in acute and chronic viral hepatitis

To analyze interleukin-2-dependent immunoregulatory function in hepatitis B virus infection and in other forms of viral hepatitis, levels of soluble interleukin-2 receptors (sIL-2R) were measured by an enzyme-linked assay in sera from patients with acute and chronic viral hepatitis of different etiology. Increased sIL-2R levels were detected in the early phase of acute hepatitis type A and type B, but not during acute non-A, non-B hepatitis. Among 46 patients with chronic hepatitis B virus infection, levels of sIL-2R were significantly increased only in cases with chronic active hepatitis, while they were about normal in chronic persistent hepatitis or in healthy carriers of the infection. These differences were independent of virus replication, being maintained when patients were stratified according to HB_eAg/anti-HB_e status and to serum HBV-DNA. Nine patients with chronic active hepatitis type B and high sIL-2R levels at presentation were followed prospectively for two to eight years, and in HB_eAg -positive patients, the behavior of receptor levels closely paralleled disease activity. These results, which may reflect increased shedding of IL-2R by activated T lymphocytes in patients with active destruction of HBV infected hepatocytes, indicate the usefulness and potential prognostic importance of serum slL-2R determination in patients with chronic viral hepatitis. Patients with chronic non-A, non-B hepatitis had much lower sIL-2R levels, although their liver disease was similar to hepatitis B cases, suggesting that different pathogenetic mechanisms operate in these patients.