Interleukin-2 Receptor In Patients Research Articles

Clinical significance of serum and vitreous soluble interleukin-2 receptor in patients with intraocular lymphoma

BackgroundIntraocular lymphoma (IOL) is a masquerade syndrome that mimics uveitis, making diagnosis difficult. The serum soluble interleukin-2 receptor (sIL-2R), which is cleaved by matrix metalloproteinase (MMP) -2 and MMP-9, has been recognized as a tumor-related biomarker of malignant lymphomas. The aim of this study was to review the reliability of serum and vitreous sIL-2R for distinguishing IOL from uveitis.MethodsPatients who underwent diagnostic vitrectomy for marked vitreous haze at Hokkaido University Hospital between April 2014 and June 2019 were enrolled. The patients were divided into an IOL group and a uveitis group, according to the pathology of their vitreous samples. The IOL group was further divided at the time of vitrectomy into patients who already had extraocular involvement (IOL with extraocular involvement group) and patients with no evidence of having extraocular involvement (IOL without extraocular involvement group). Serum sIL-2R, and intravitreal sIL-2R, MMP-2, and MMP-9 levels were assessed.ResultsTwenty-five eyes of 25 patients, and 15 eyes of 15 patients were included in the IOL group and uveitis group, respectively. The serum sIL-2R levels were significantly lower in the IOL group than in the uveitis group (P < 0.05), and 20.0% and 66.7% in the IOL and the uveitis group showed high sIL-2R value above the normal range. Vitreous sIL-2R tended to be higher in the IOL group than in the uveitis group (P = 0.80). Serum sIL-2R was significantly lower in the IOL without extraocular involvement group than in the IOL with extraocular involvement group (P < 0.05); 5.9% in the IOL without extraocular involvement group and 50.0% in the IOL with extraocular involvement group showed high sIL-2R value above the normal range. Vitreous sIL-2R, MMP-2, and MMP-9 tended to be higher in the IOL with extraocular involvement group than in the IOL without extraocular involvement group (P = 0.30, < 0.05, 0.16).ConclusionsSerum sIL-2R is often within the normal range in IOL patients. Even if it is within the normal range, the possibility of IOL should be considered. Serum sIL-2R is not a reliable biomarker for IOL, whereas vitreous sIL-2R may be useful for the diagnosis of IOL.

Increased vitreous levels of B cell activation factor (BAFF) and soluble interleukin-6 receptor in patients with macular edema due to uveitis related to Behçet's disease and sarcoidosis.

Uveitis accounts for 10-15% of all cases of blindness in the developed world. Uveitic macular edema (UME) is a primary cause of permanent visual impairment in patients with uveitis. Because proinflammatory mediators elicit inflammation and lead to UME, we determined the profiles of proinflammatory mediators associated with complications, such as ME, in the vitreous humor of patients with panuveitis related to Behçet's disease (BD) and sarcoidosis. In this retrospective study, we enrolled 21 patients with uveitis, including 6 with BD and 15 with sarcoidosis, and 15 patients with idiopathic epiretinal membrane (iERM) at the Department of Ophthalmology, Kyushu University Hospital, between January 2008 and April 2016. Vitreous concentrations of 32 proinflammatory mediators, including cytokines and soluble receptors of tumor necrosis factor (TNF) and interleukin (IL)-6 families, were assessed using a bead-based multiplex assay and their association with clinical data was examined. The levels of proinflammatory mediators, including a proliferation-inducing ligand (APRIL), B cell activating factor belonging to the TNF family (BAFF), soluble cluster of differentiation 30 (sCD30), soluble TNF receptor-1 (sTNFR1), sTNFR2, TNF-α, IL-6, and soluble IL-6 receptor-α (sIL-6Rα), were significantly higher in patients with uveitis. With regard to clinical parameters in patients with uveitis, vitreous levels of BAFF and sIL-6Rα were prominently elevated in patients with UME compared to in those without UME (P < 0.01, respectively). Our results suggest that elevated vitreous levels of BAFF and sIL-6Rα are associated with the pathogenesis of UME in patients with panuveitis related to BD and sarcoidosis.

MicroRNA-30b participates in the pathological process of hyperuricemia by regulating interleukin-6 receptor

The present study aimed to examine the expression of hyperuricemia (HUA)-related factors in the body fluids of HUA patients and in renal tissues and body fluids of HUA mice to elucidate the underlying mechanism of HUA and provide theoretical basis for the diagnosis, prevention and treatment of this disease. A total of 51 HUA patients (HUA group), and 36 healthy subjects (control group) were included in the present study. The peripheral blood and urine were collected from all patients and healthy subjects. A total of 20 male Kunming mice were used to construct HUA model, and another 20 mice were used as controls. The kidney tissues, peripheral blood and urine were collected from all mice. ELISA was performed to determine the levels of interleukin-6 receptor (IL-6R) proteins in the serum and urine of human or mice, while western blotting was employed to determine the protein expression in the kidney tissues of mice. Quantitative real-time polymerase chain reaction was used to measure the expression of mRNA and miR-30b in all sample types. Dual luciferase reporter assay was performed to identify the direct interaction between 3′-untranslated region of IL-6R mRNA and miR-30b. The expression of IL-6R mRNA and protein was increased in serum and urine of HUA patients, while the expression of miR-30b was reduced in HUA patients when compared with healthy subjects. The contents of uric acid, urea nitrogen and creatinine in the blood of HUA mice model were significantly elevated. Similarly, the expression of IL-6R mRNA and protein was increased in kidney, serum and urine of HUA mice model, while the expression of miR-30b was reduced in kidney tissues, serum and urine of HUA mice model. Dual luciferase reporter assay showed that miR-30b was able to bind with 3′-UTR seed region of IL-6R mRNA to regulate its expression. These findings demonstrated that the expression of IL-6R in patients and mouse with HUA is elevated, which is related with the down-regulation of miR-30b. Therefore, miR-30b might participate in the pathological process of HUA by regulating IL-6R.

Soluble interleukin-6 receptor in patients with JAK2V617F somatic mutation and myeloproliferative neoplasm

Soluble interleukin-6 receptor in patients with JAK2V617F somatic mutation and myeloproliferative neoplasm

Serum Levels of Interleukin-8 and Soluble Interleukin-6 Receptor in Patients with Stage-I Multiple Myeloma: A Case-Control Study.

Objective:Multiple myeloma (MM) remains an incurable disease that needs better recognition and further research. Previous studies elucidated the interaction between myeloma cells and showed the necessity of bone marrow stromal cells for the initiation and progression of MM. Many chemokines and their receptors including interleukin-8 (IL-8) and soluble interleukin-6 receptor (sIL-6R) play important roles in this interaction. The main purpose of this study is evaluating the serum level of IL-8 and sIL-6R on stage-I of MM patients and healthy controls. Methods:Serum samples from 30 stage-I MM patients (13 males and 17 females) and 30 healthy subjects as controls (13 males and 17 females) were examined in this study. The protein concentrations of serum IL-8 and sIL-6R were assessed by enzyme-linked immunosorbent assay (ELISA). Results:The mean level of IL-8 and sIL-6R were significantly elevated in stage-I MM. The mean levels of IL-8 were 1246.57±279.22 ng/ml in stage-I MM and 902.53± 294.61 ng/ml in controls (P<0.001). The mean levels of sIL-6R were 5.39±1.38 ng/ml and 4.1±1.14 ng/ml in stage-I MM and controls, respectively (P<0.001). The mean levels of IL-8 were 1342.18±193.4 ng/ml in patient females and 859± 278.2ng/ml in control females (P <0.001). The mean levels of sIL-6R were 5.21±1.55 ng/ml and 3.91±1.22 ng/ml in patient females and control females, respectively (P=0.01). The mean level of sIL-6R in patient males and control males were 5.63±1.43 ng/ml and 4.34±1.04 ng/ml, respectively (P=0.01). A significant correlation (Pearson’s correlation = 0.45, P=0.008) was observed in the population of females (patients and controls). Conclusion:The results of study suggest the possible involvement of IL-8 and the sIL-6R at stage-I MM and can better characterize the role of chemokines and their receptors in the disease process, especially in the early stages.

The significance of serum levels of soluble interleukin-2 receptor in patients undergoing maintenance hemodialysis

Background Elevated serum levels of sIL-2R are commonly observed in patients undergoing maintenance hemodialysis (MHD). However, the clinical implications in these subjects are unclear. This study is aimed to assess the significance of elevated sIL-2R levels in MHD patients. Methods A total of 382 MHD patients were followed-up from September 2016 to December 2019. Patients were divided into two groups: high sIL-2R, with sIL-2R levels ≥2-fold of the upper limit of normal (710 U/ml); and low sIL-2R, with sIL-2R levels < 2-fold the upper limit of normal. The relationships between sIL-2R levels and other clinical parameters, as well as patient prognosis were both assessed. Results The median concentration of sIL-2R was 1268 U/mL. A total of 372 (97.38%) patients exhibited sIL-2R levels higher than the upper limit of the normal range. Multiple linear regression analysis revealed that monocyte count (β = 0.1571, p = 0.01), and β2-MG (β = 0.2635, p < 0.0001), hemoglobin (β = −0.1610, p = 0.001), SCr (β = −0.3471, p < 0.0001), and HDL-C (β = −0.1091, p = 0.029) levels were independent factors influencing serum concentrations of sIL-2R. High sIL-2R was significantly correlated with non-cardiovascular-related mortality (OR 2.97 [95% CI 1.59–5.56; p = 0.001), of which 39 (82.98%) were attributed to infection and/or cancer. Conclusions Elevated sIL-2R is prevalent in MHD patients and related with several unfavorable parameters. sIL-2R appears to have no ability to predict cardiovascular mortality, which accounts for approximately one-half of all deaths. However, sIL-2R may be beneficial in predicting noncardiovascular mortality.

The serum concentration of soluble interleukin-2 receptor in patients with Kawasaki disease.

Kawasaki disease is a febrile disease of childhood that is associated with increased inflammatory cytokines and immunoregulatory abnormalities. While the serum concentrations of soluble IL-2 receptor can change under such pathologies, the relevance of the soluble IL-2 receptor concentration in patients with Kawasaki disease has not been specified. We aimed to summarize the existing studies that reported the soluble IL-2 receptor concentrations in patients with Kawasaki disease. Original articles that were published up to July 2016 were collected using a PubMed/Medline-based search engine. A total of nine articles that reported the serum soluble IL-2 receptor concentrations in acute-phase Kawasaki disease were eligible. All of the articles described a high soluble IL-2 receptor concentration in patients with Kawasaki disease relative to the level of controls or the reference range. Two of five articles on patients with coronary artery aneurysms described a significantly higher soluble IL-2 receptor concentration in patients with coronary artery aneurysms than patients without. Two articles on patients with intravenous immunoglobulin therapy described a significant decrease of the soluble IL-2 receptor concentration after the therapy. Accordingly, the serum soluble IL-2 receptor can be a potent marker of disease activity and therapeutic effects in patients with Kawasaki disease; further studies are thus warranted for its use in the clinical setting.

Diagnostic value of soluble interleukin-2 receptor in patients with lymphoproliferative diseases

Diagnostic value of soluble interleukin-2 receptor in patients with lymphoproliferative diseases

Clinical Significance of Soluble Interleukin-2 Receptor in Patients with Acute Leukemia

Objective: Investigate the expression level and clinical significance of serum soluble interleukin-2 receptor (sIL-2R, sCD25) in patients with acute leukemia.Methods: Serum sCD25 level were measured using enzyme linked immunosorbent assays (ELISA) in 97 acute leukemia patients and 10 healthy contrlols. Clinical and laboratory features, including bone marrow cellularity, white blood cell count (WBC), platelets (PLT), lactate dehydrogenase (LDH), serum ferritin (SF), erythrocyte sedimentation rate (ESR), as well as overall survival (OS) data were collected.Results: (1) Serum sCD25 level of the newly diagnosed leukemia group was significantly higher than that of the control group (P<0.0001). (2) Among the newly diagnosed AML patients, serum sCD25 level of the M3 group was significantly lower than that of the M2 or non-M2/M3 group (P<0.05). In addition, serum sCD25 level of the low/intermediate risk (AML) or standard risk (ALL) group was lower than that of the high risk group (P<0.05). (3) Serum sCD25 level of the complete remission (CR) group was significantly lower than that of the newly diagnosed group (P<0.002). However, no significant decrease was found in serum sCD25 level of the relapsed/refractory group compared to that of the newly diagnosed group. (4) Serum sCD25 level in newly diagnosed patients was positively correlated with peripheral WBC, LDH and SF. (5) Furthermore, although OS of the low sCD25 level group (sCD25<2000pg/ml) was not significantly different compared to the intermediate sCD25 level group (2000≤sCD25≤4000pg/ml) (P =0.532), both that of the low or intermediate sCD25 level group were significantly superior to that of the high sCD25 level group (sCD25>4000pg/ml) (P<0.05).Conclusion: Serum sCD25 levels have important clinical significance in evaluating disease activity, treatment outcomes and prognosis in patients with acute leukemia. DisclosuresNo relevant conflicts of interest to declare.

Clinical Significance of Serum-Soluble Interleukin-2 Receptor in Patients With Follicular Lymphoma

Although sIL-2R level has a prognostic value in patients with diffuse large B-cell lymphoma, its clinical role in patients with follicular lymphoma has not been determined. We reviewed data on 70patients diagnosed with follicular lymphoma. Ann Arbor stage was I, II, III, and IV in 6, 9, 17, and 38patients, respectively, and grade classification according to the World Health Organization criteria was 1, 2, 3A, 3B, and not available in 28, 15, 11, 4, and 12 patients, respectively. sIL-2R at diagnosis was significantly correlated with Ann Arbor stages (P< .001), number of nodal lesions (≥ 5 or not) (P= .0050), and Follicular Lymphoma International Prognosis Index risk classification (P= .0015). Furthermore, sIL-2R regressed significantly in patients who achieved complete remission, uncertain complete remission, or partial remission (P< .001), and increased when regrowth of lymphoma was shown (P< .001). Finally, a high level of sIL-2R at diagnosis was correlated with shorter progression-free survival (P= .018) and time to next treatment (P< .001). Serum-soluble interleukin-2 receptor is correlated with tumor burden at diagnosis and during the clinical course of therapies in patients with follicular lymphoma, and our data support its usefulness to function as a surrogate marker of tumor progression.

Elevated circulating soluble interleukin-2 receptor in patients with chronic liver diseases is associated with non-classical monocytes

BackgroundThe soluble interleukin-2 receptor (sIL-2R, sIL2R, sTAC, sCD25) is a reliable biomarker for disease activity in inflammatory disorders such as sarcoidosis. Based on the essential pathogenic role of inflammation for progression of liver diseases, we hypothesized that sIL-2R might be an indicator of inflammatory cell activation and disease severity in patients with chronic liver diseases (CLD).MethodsWe measured sIL-2R serum levels in 71 patients with different stages and etiologies of CLD in comparison to 41 healthy controls. Serum sIL-2R concentrations were correlated with laboratory markers of liver diseases, cytokine / chemokine levels and circulating immune cell subpopulations as simultaneously assessed by FACS analysis from peripheral leukocytes.ResultsCLD patients showed significantly elevated serum sIL-2R levels compared with controls. sIL-2R was significantly higher in patients with compared to patients without established liver cirrhosis and increased with the Child-Pugh stage of cirrhosis, independent of the underlying etiology. sIL-2R levels correlated inversely with parameters indicating the hepatic biosynthetic capacity, such as albumin or international normalized ratio, and positively with non-invasive markers of liver fibrosis such as hyaluronic acid or procollagen-III-peptide. Circulating immune cells might represent a major source of sIL-2R. In fact, sIL2-R levels correlated closely with circulating monocytes, especially non-classical CD14+ CD16+ monocytes, which were found to express high levels of CD25 by FACS. Pro-inflammatory cytokines, including IL-2, IFNγ or IL-6, and chemokines were also associated with sIL2-R. In addition, renal failure was an important confounder of sIL-2R levels independent of liver dysfunction and inflammation.ConclusionssIL-2R is elevated in patients with liver diseases and cirrhosis, is associated with circulating inflammatory cells and is increased in concomitant renal failure. These data indicate that sIL-2R might be a potential marker for immune cell activation in CLD, especially for proinflammatory and profibrogenic non-classical CD14 + CD16+ monocytes.

Serum levels of IgG4 and soluble interleukin-2 receptor in patients with coronary artery disease

BackgroundImmunoglobulin G4 (IgG4)-related immuno-inflammation has been suggested to play a role in the development of remodeling of arterial wall. We investigated the association between serum concentrations of IgG4 or soluble interleukin-2 receptor (sIL-2R) and coronary artery disease (CAD). MethodsSerum concentrations of IgG4 and sIL-2R were measured in 286 patients who underwent coronary angiography. ResultsIn patients with CAD, the medians of serum concentrations of IgG4 (39.3mg/dl) and sIL-2R (388 U/ml) were significantly higher than corresponding values in patients without CAD (IgG4 27.0mg/dl, sIL-2R 312 U/ml). In receiver-operating characteristic curve analysis, the area under the curve of sIL-2R and IgG4 for the presence of CAD was 0.634 and 0.632, respectively. Age- and gender-adjusted logistic regression analysis showed that both of the fourth quartile of sIL-2R concentrations (≥509 U/ml) and that of IgG4 concentrations (≥57.7mg/dl) were found to be associated with CAD with an odds ratio of 2.82 and 4.08, respectively, compared with the corresponding lowest quartile. ConclusionsSerum concentrations of IgG4 and sIL-2R were increased in patients with angiographically-proven CAD, suggesting that IgG4-related immuno-inflammation may also have a role in the development and/or progression of coronary artery atherosclerosis.

Serum soluble interleukin-2 receptor in patients with pulmonary mycobacterial diseases

Serum soluble interleukin-2 receptor (sIL-2R) levels were measured in patients with untreated pulmonary tuberculosis (24 cases), patients with multidrug-resistant intractable pulmonary tuberculosis (7 cases) and patients with pulmonary non-tuberculous mycobacteriosis (27 cases). Serum sIL-2R levels were elevated in patients with pulmonary mycobacterial diseases and were elevated in untreated pulmonary tuberculosis patients than in other patients. In patients with new tuberculosis, serum sIL-2R levels were higher in patients with extensive lesions. Serum sIL-2R level showed significant positive correlation with serum C-reactive protein level and erythrocyte sedimentation rate, and significant negative correlation with serum albumin level. In patients with intractable tuberculosis and patients with non-tuberculous mycobacteriosis, serum sIL-2R levels were lower than in patients with new tuberculosis. Even in patients with extensive lesions, serum sIL-2R levels were not elevated. Lower levels of serum sIL-2R, marker of immunocompetent cell activity, suggested that immunocompetent cell activity was suppressed in intractable tuberculosis and in non-tuberculous mycobacteriosis.

Effects of Jinlong Capsule on expressions of interleukin-2 and soluble interleukin-2 receptor in patients with primary liver cancer after transarterial chemoembolization therapy

To observe and discuss the dynamic changes of interleukin-2 (IL-2) and soluble interleukin-2 receptor (sIL-2R) and their significance in the patients with primary liver cancer after transarterial chemoembolization (TACE) therapy combined with Jinglong Capsule. A total of 48 patients with primary liver cancer, who failed to be treated by major surgery, were randomly divided into two groups: Jinlong Capsule group (TACE therapy plus Jinlong Capsule) and control group (TACE therapy alone). There were 24 cases in each group. The levels of peripheral blood IL-2 and slL-2R were measured before the first TACE and 1, 7 and 15 days after the second TACE respectively by using double-antibody sandwich enzyme-linked immunosorbent assay. The data from Jinlong Capsule group were compared with those from the control group. The level of sIL-2R in Jinlong Capsule group was significantly lower than that in the control group (P<0.05), while the level of IL-2 was significantly higher than that in the control group (P<0.05). Jinlong Capsule can significantly improve the lymphocyte function of the patients with primary liver cancer after TACE. The levels of IL-2 and sIL-2R can be considered as the valuable parameters for evaluating the effects on primary liver cancer, and Jinlong Capsule is helpful for the patients with primary liver cancer.

INTERLEUKIN-2 RECEPTOR LEVELS IN PATIENTS WITH ACTIVE PULMONARY TUBERCULOSIS BEFORE AND AFTER ANTITUBERCULOUS CHEMOTHERAPY

PURPOSE: It has been long recognized that T Lymphocytes are essential in the immunity against tuberculosis. This study aimed to evaluate serum levels of interleukin-2 receptors in patients with active pulmonary tuberculosis and their levels change following antituberculosis chemotherapy.

Elevation of soluble interleukin-2 receptor in patients with non-small cell lung cancer treated with gefitinib

We previously reported that plasma thromboxan B(2), soluble P-selectin, and serum regulated on activation, normal T-cell expressed and secreted (RANTES) were elevated after gefitinib treatment. We hypothesized that gefitinib could activate T-lymphocytes via activated platelets, and so we measured serum levels of soluble interleukin-2 receptor (sIL-2R) in patients medicated with gefitinib. Twenty-one patients with non-small cell lung cancer (NSCLC) were entered into this study. All patients received gefitinib over 2 weeks without severe adverse effects. Blood samples were withdrawn from all patients before and after the administration of gefitinib and plasma soluble P-selectin, serum RANTES, and serum sIL-2R were measured by enzyme-linked immunosolvent assay. In addition, we carried out the basic study of the interleukin-2 receptor (IL-2R) expression on CD4(+) lymphocytes by RANTES. Plasma soluble P-selectin, serum RANTES, and serum sIL-2R levels increased significantly in patients receiving gefitinib treatment for 1 and 2 weeks. RANTES did not induce the expression of IL-2R on CD4(+) lymphocyte. However, the anti-CD3 monoclonal antibody-induced expression of IL-2R was enhanced by the addition of RANTES. Our finding indicated that lymphocytes were activated by gefitinib treatment. We think that sIL-2R elevation after gefitinib administration may be a factor positively effecting patients with NSCLC. It is deemed possible that the effect of gefitinib is induced not only by its blocking of the tyrosine kinase of epidermal growth factor receptor but also by antitumor immunity via its activation of T-cells.

Study of the effect of leeching on plasma endothelin and soluble interleukin-2 receptor in patients with systemic lupus erythematosus

to explore the mechanism of leeching in treating systemic lupus erythematosus (SLE). Forty-four patients with SLE were randomly divided into conventional corticosteroid treated group (control group, n = 20) and conventional treatment group with leeching intervention added (leeching group, n = 24). Before and after treatment the concentration of plasma endothelin (ET) and soluble interleukin-2 receptor (sIL-2R) were determined. Before treatment the level of plasma ET and sIL-2R in the SLE patients were all higher than those in the normal healthy group, (P < 0.01). But after treatment the level of these in both groups were significantly improved than those of before treatment (P < 0.05), and comparison between these two treated groups showed that the difference between them was significant (P < 0.05). Leeching added to conventional treatment of SLE could be more effective in improving the level of plasma ET and sIL-2R, and ameliorating the impairment of renal tissues.

Serum soluble interleukin-2 receptor (IL-2R) and immunohistochemical staining of IL-2R/Tac antigen in colorectal cancer.

In the present study, we investigated the significance of serum soluble interleukin-2 receptor (IL-2R) as a tumor marker, and examined the existence and localization of cells positive for IL-2R/Tac antigen in colorectal cancer tissues and their regional lymph nodes. The study included 155 patients with colorectal cancer. Levels of serum soluble IL-2R were measured by an enzyme-linked immunosorbent assay. In the tissues obtained from 18 patients, immunohistochemical staining was performed, with the use of the avidin-biotin-peroxidase complex technique, in which mouse anti-human IL-2R antibody was used. The preoperative levels of serum soluble IL-2R in patients with colorectal cancer were significantly higher than those of normal controls ( P = 0.0065). The levels of serum soluble IL-2R in patients with metastatic lymph nodes were also significantly higher than the levels in those without metastatic lymph nodes ( P = 0.0258). Concerning tumor markers, there were significant differences in serum soluble IL-2R levels between patients who were positive and those who were negative for carcinoembryonic antigen (CEA) and between these who were positive and those who were negative for immunosuppressive acidic protein (IAP). In the immunohistochemical staining of IL-2R, 16 of the 18 patients (88.8%) showed IL-2R-positive cells in the colorectal cancer tissues. In regard to the metastatic lymph nodes, all of 5 patients (100%) showed IL-2R-positive cells. On the other hand, IL-2R-positive cells were not recognized in normal colorectal tissues and non-metastatic lymph nodes. These results suggest that activated T lymphocytes infiltrating into cancer tissues to play an antitumor role may release a large amount of the alpha-chain of IL-2R, resulting in the high levels of serum soluble IL-2R in patients with colorectal cancer.

Mechanism of increased serum soluble interleukin-2 receptor levels in patients on continuous ambulatory peritoneal dialysis.

The aim of this study was to investigate the mechanism underlying the increase of serum soluble interleukin-2 receptor (IL-2R) levels in patients on continuous ambulatory peritoneal dialysis. In 13 dialysis patients and 17 healthy controls, serum soluble IL-2R levels were determined by enzyme-linked immunosorbent assay, and CD25-positive (cell surface IL-2R-positive) cells were detected by flow cytometry. Soluble IL-2R levels were also measured in the supernatant of cultured peripheral blood mononuclear cells. The serum soluble IL-2R level was significantly higher in the patients than in the healthy controls (p < 0.0001). In contrast, both the percentage and the absolute count of CD25-positive cells showed no significant differences, and neither did the soluble IL-2R level in culture supernatant. Serum soluble IL-2R levels showed a positive correlation with the serum beta2-microglobulin level (p < 0.01), the age of the patients (p < 0.05), and duration of dialysis (p < 0.05), as well as a negative correlation with the urine volume (p < 0.05). The increase of serum soluble IL-2R in patients on peritoneal dialysis may be caused by accumulation due to its low transperitoneal clearance and low urinary excretion.

Serum concentrations of soluble interleukin-2 receptor in patients with malignant brain tumors.

Interleukin-2 receptor alpha (IL-2Ralpha) can combine with IL-2 firmly, and soluble IL-2Ralpha (sIL-2Ralpha) is elevated in sera from patients with various types of cancers. To investigate the role of this receptor, we studied the changes of serum sIL-2Ralpha in patients with malignant brain tumors. SIL-2Ralpha was measured in 100 patients with malignant brain tumors (63 cancer metastasis, 16 malignant gliomas, 21 malignant lymphomas), and 51 patients with cancer who had no distant metastasis such as brain metastasis. In patients with 35 metastatic brain tumors from lung cancer, the levels of sIL-2Ralpha were not significantly different from levels in normal volunteers (311 +/- 62.4 U/ml). In patients with 25 metastatic brain tumors from lung adenocarcinoma, the mean level of serum sIL-2Ralpha was 352 +/- 94.0 U/ml. These same patients showed high levels of serum sIL-2Ralpha (492 +/- 101 U/ml) with regional lymph nodes metastasis. Serum sIL-2Ralpha concentration in 16 patients with malignant glioma varied greatly with the mean concentration of 328 +/- 192 U/ml. In 5 of 16 patients with malignant glioma, we could detect the significant increase of serum sIL-2Ralpha concentration from early stage of recurrence. Serum levels of sIL-2Ralpha could be a useful immunological marker in patients with malignant brain tumors.