Interleukin-6 level in serum and ascites as a prognostic factor in patients with epithelial ovarian cancer.

BACKGROUND: Interleukin-6 (IL-6) is a multifunctional cytokine that can be produced by human ovarian cancer cells. Elevated IL-6 levels have been found in the serum and ascites of patients with ovarian cancer, but its role in this disease has not been clearly established. METHODS: The authors studied the relationship between IL-6 levels in serum and ascites, various tumor parameters, and survival in 70 patients with newly diagnosed, untreated epithelial ovarian cancer. Ascites and serum specimens were obtained at the time of initial surgery, and IL-6 levels were determined using the B9 bioassay. RESULTS: All patients underwent platinum-based chemotherapy after initial surgery. The median age of the group was 62 years (range, 28-87 years), and the median follow-up time was 13 months (range, 12-59 months). Significantly higher IL-6 levels were detected in patients' ascites (median, 49,612 pg/ml [range, < 1 to 680,330 pg/ml]) compared with serum (median, 10 pg/ml [range, < 1 to 1221 pg/ml]) (P < 0.0001). IL-6 levels in ascites correlated significantly with the volume of ascites (P < 0.0001) and nearly so with the size of tumor found at initial surgery (P = 0.05). Serum and ascites IL-6 levels did not correlate statistically with overall survival time, tumor stage, grade, histologic findings, residual tumor volume after debulking, and serum CA 125 levels. Although not statistically significant, patients who responded to chemotherapy tended to have lower ascites IL-6 levels (median, 21,102 pg/ml) compared with patients who did not respond to chemotherapy (median, 40,200 pg/ml). CONCLUSIONS: IL-6 is present in very high amounts in the ascites of patients with epithelial ovarian cancer. IL-6 levels in ascites correlated significantly with ascites volume and initial tumor size. IL-6 levels in ascites and serum did not correlate statistically with other tumor parameters or with survival time.

Molecular cloning of the human kidney differentiation antigen gp160: human aminopeptidase A.

gp160 is a cell surface differentiation-related glycoprotein of 160 kDa expressed by epithelial cells of the glomerulus and proximal tubule cells of the human nephron but only by a subset of renal cell carcinomas (RCCs). We have reported that gp160 expression correlates with the resistance of cultured RCCs to the antiproliferative effects of alpha interferon, while lack of expression correlates with sensitivity to alpha interferon. In this study, we have purified gp160 protein, obtained partial sequences of random peptides, and isolated a full-length cDNA. The gp160 cDNA possesses 78% homology to the murine BP-1/6C3 antigen, a B-lymphocyte differentiation protein that exhibits aminopeptidase A (APA; EC 3.4.11.7) activity. Enzymatic assays on human RCC cell lines indicated a 100% concordance between APA activity and gp160 expression. APA activity of gp160-expressing RCC cells was increased or decreased by a panel of APA activators or inhibitors, respectively. Furthermore, anti-gp160 monoclonal antibodies immunoprecipitate APA activity from RCC cell lysates and selectively deplete APA activity from RCC cell extracts. These data indicate that the gp160 human kidney/RCC glycoprotein is human APA.

Interleukin-10 production by human carcinoma cell lines and its relationship to interleukin-6 expression.

Recent data indicate a major role for IL-10 in suppressing immune and inflammatory reactions. To date, expression of human IL-10 has been attributed primarily to helper T lymphocytes, activated monocytes, and neoplastic B cells, and was often found to be associated with IL-6 expression. In this study we sought to determine whether non-hematopoietic human tumor cell lines produce IL-10 and, if so, what is the relationship between IL-10 and IL-6. Using ELISA, we determined IL-10 and IL-6 levels in culture supernatants of 48 cell lines established from carcinomas of the kidney, colon, breast and pancreas, malignant melanomas and neuroblastomas. IL-6 protein was secreted by 28 of the tumor cell lines; IL-10 was measurable in 15 cell lines. IL-6 secretion was maximal and most frequent in renal-cancer cell lines, while IL-10 production was found to be highest and most common among cell lines derived from colon carcinomas. IL-10 in conditioned medium of one of the colon carcinoma cell lines (CCL222) was bio-active, as demonstrated in the mouse MC/9 mast-cell-line assay and in human mixed-lymphocyte reactions. In both assays, IL-10 bio-activity was neutralized by an anti-IL-10 monoclonal antibody. Expression of IL-6 and IL-10 was confirmed by RNA analysis using message amplification by PCR and sequencing of amplified cDNA. LPS, IL-1 alpha, and TNF-alpha strongly enhanced the release of IL-6 by RCC cells, but only marginally affected IL-10 production in colon-carcinoma cells. IL-10 secretion by colon-carcinoma cells was moderately stimulated by IFN-gamma and IL-4. Dexamethasone suppressed the release of IL-6, but had no inhibitory effect on IL-10 secretion. Our results demonstrate that tumor cell lines established from certain types of human carcinomas are capable of expressing and releasing IL-6 and/or IL-10, suggesting a role of these cytokines in solid-tumor development and anti-tumor immunity.

Immune response in chronic Schistosomiasis haematobium and mansoni. Reversibility of alterations after anti-parasitic treatment with praziquantel.

Peripheral blood mononuclear cells from Sudanese children heavily infected with Schistosoma haematobium and S. mansoni were examined for lymphocyte subpopulations, for mitogen and antigen responsiveness, and for natural killer (NK) cell activity before and 5 months after treatment with praziquantel. The humoral immune response was simultaneously investigated by determination of parasite-specific IgG and IgE antibodies, IgE-containing circulating immune complexes, and circulating schistosome antigen. A single dose treatment with praziquantel (40 mg/kg) resulted in a normalization of numerical imbalances in lymphocyte subpopulations, a significant increase in the blastogenic response upon stimulation with adult worm antigen, phytohaemagglutinin (PHA), and concanavalin A (Con A), and restoration of natural killer (NK) cell-mediated lysis of K562 targets. These findings were paralleled by a remarkable decrease in parasite-specific IgE antibodies, IgE-containing circulating immune complexes, and circulating schistosome antigen. The results indicate that the modulation of immune responses in chronic schistosomiasis is associated with active infection and is reversible after successful chemotherapy.

Human schistosomiasis: deficiency of large granular lymphocytes and indomethacin-sensitive suppression of natural killing.

Twenty-eight children infected with Schistosoma haematobium and S. mansoni were tested for natural killer (NK) cell activity in vitro using the myeloid/erythroid cell line K562 as target. In addition, the frequency of large granular lymphocytes (LGL) and the number of HNK-1+ lymphocytes were examined in peripheral blood. NK cell activity was found to be markedly reduced in most patients when compared with a group of healthy Caucasian individuals (P less than 0.005). Moreover, the impairment of NK activity clearly correlated with the intensity of infection, which was quantified by parasite ova excretion in stool and urine. Within the lymphocyte compartment the percentages of cells with the NK phenotype (HNK-1+) were found to be normal, although the majority of patients exhibited decreased numbers of LGL (P less than 0.005). The absolute and relative frequencies of LGL and HNK-1+ lymphocytes by no means correlated with the parasite load. In vitro results suggest an at least partly prostaglandin-mediated and interferon-resistant functional defect of NK cells.

Relationship between intensity of infection and immunomodulation in human schistosomiasis. I. Lymphocyte subpopulations and specific antibody responses.

Cellular and humoral immune responsiveness in 44 Sudanese children with schistosomiasis was studied and related to the intensity of infection. The parasite load was quantitated by accurate assessment of the excretion of ova of S. mansoni and S. haematobium in stool and urine, respectively. Lymphocyte subpopulations (T3+, T4+, T8+, TAC+, HNK1+, Ia+, SIg+, LGL+, ANAE+) as well as specific IgE and IgG antibodies to adult schistosome antigens were determined. The relationships existing between intensity of infection and cellular and humoral immune responsiveness revealed a distinct pattern of anti-parasite immunity: The percentage of pan-T cells (T3+) and the T helper (T4+):T suppressor (T8+) ratio were inversely correlated to the intensity of infection. In contrast, the percentage of T suppressor cells positively correlated to the parasite load. Ia+, TAC+, HNK1+ and T4+ cell counts did not show a significant relationship to worm burden. Specific IgE and IgG antibodies to S. mansoni and S. haematobium adult worm antigen clearly increased with the parasite load. The dichotomy of decreased T cell parameters and increased antibody response in heavily infected individuals represents a unique feature in helminthic infections.

Relationship between intensity of infection and immunomodulation in human schistosomiasis. II. NK cell activity and in vitro lymphocyte proliferation.

Natural killer (NK) cell activity against K-562 targets and lymphoproliferative responses to Con A, interleukin-2 (IL-2) and Con A + IL-2 were examined in a group of 41 Sudanese children suffering from schistosomiasis mansoni and haematobium. The results were correlated to the intensity of infection as determined by enumeration of parasite ova in urine and stool. NK cell activity measured at three effector to target cell ratios was significantly depressed in the patient group as compared to a German control group. Impairment of NK cell activity showed a direct relationship with the patients' parasite load. Furthermore lymphoproliferation to Con A, IL-2 and Con A + IL-2 was depressed in the group of patients. Interestingly the costimulation effect of IL-2 expressed as coefficient of delta ct/min(Con A + IL-2)/delta ct/minCon A correlated significantly to the intensity of infection suggesting that lymphocytes from heavily infected patients were defective in producing appropriate amounts of IL-2 in response to Con A. Our findings support the concept that heavy infections with S. mansoni and/or S. haematobium induce a peculiar dichotomy of cellular and humoral immune parameters. Whereas T cell-dependent cellular immune responsiveness and NK cell function decrease with increasing worm burden specific IgE and IgG antibody responses increase.

Numerical and functional alterations of lymphocytes in human schistosomiasis.

Peripheral blood mononuclear cells from 29 Sudanese children heavily infected with Schistosoma haematobium and S. mansoni were examined for lymphocyte subpopulations, for mitogen responsiveness in the absence and presence of interleukin-2 (IL-2), and for natural killer (NK) cell activity. The nutritional status was assessed by anthropometric and biochemical measurements. In comparison with a group of healthy Caucasian individuals the children with schistosomiasis showed a profound alteration of their cellular immune variables, reflecting a severe acquired immunodeficiency syndrome. The T-cell compartment, in particular the OKT4+ helper/inducer subset, was numerically reduced at the expense of an increased B-cell compartment. The patients' OKT4/OKT8 ratios were significantly diminished (median, 1.2; 95% confidence limits, 0.8-1.7) corresponding to a decreased responsiveness to the T-cell mitogen concanavalin A. Since addition of exogeneous IL-2 significantly enhanced the patients' lymphocyte proliferation in response to Con A, a defective IL-2 production was assumed to be at the origin of the impaired mitogenic response in chronic schistosomiasis. With regard to NK cell activity, most patients' lymphocytes failed to mediate significant cytotoxicity against the K562 target cell line, although normal percentages of cells with the NK phenotype (HNK-1+) were present. The results are discussed in view of immunological alterations seen in other parasitic infections with a heavy parasitic load.