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Biomedical subjects

C Nerl

Publications and source records attributed to C Nerl.

At least 55 records · Page 3Linked to original sources

[The prognostic significance of lymphocyte subpopulations and macrophages in peripheral blood and in bronchoalveolar lavage in AIDS patients with suspected Pneumocystis carinii pneumonia].

In 36 HIV seropositive patients with the clinical manifestation of AIDS and a suspected Pneumocystis carinii infection, lymphocyte subpopulations were analyzed in the peripheral blood (PBL) and compared with the results of the bronchoalveolar lavage (BAL). Of those 36 patients, 29 showed a highly abnormal CD4/CD8 ratio in both the PBL and the BAL. The clinical course of these 29 patients was unpredictable. In seven patients, however, the CD4/CD8 ratio in the BAL was normal or only slightly altered, despite a highly abnormal CD4/CD8 ratio in the PBL. Five of these seven patients improved greatly during the clinical course. The positive outcome of the clinical course was even more strongly correlated with the number of macrophages in the BAL. Twelve of the 36 patients showed normal or only slightly changed numbers of macrophages in the BAL. Eleven of these twelve patients (92%) improved rapidly during antibiotic therapy, while the clinical course was unpredictable in patients with markedly reduced macrophage counts in the BAL.

Acquired Immunodeficiency Syndrome↗

Expansion of activated T lymphocytes (CD3 + HLA/DR +) detectable in early stages of HIV-1 infection.

The phenotypic characterization of lymphocyte subsets in relation to different clinical stages of HIV infection has mainly focussed on CD4 and CD8 cells. Some reports focus on expansion of activated T lymphocytes in AIDS patients. Yet there is no detailed knowledge whether such changes occur also in earlier stages of HIV infection. In order to describe the kinetics and possible pathogenetic meaning of this subset when related to all distinct chronologic stages, we performed two-color flow cytometric lymphocyte differentiation in 173 HIV-infected patients and 30 healthy controls. All subjects were classified according to the Walter Reed (WR) system. Our results show that a significant increase of activated T lymphocytes (CD3 + HLA/DR +) occurs early, in WR1 and WR2, thus preceding the clinically relevant CD4 depletion. This increase is paralleled by an expansion of CD8 + Leu7 + cytotoxic cells. We conclude, that early changes of lymphocyte subsets are detectable in addition to inversion of the CD4/CD8 ratio. The possible pathogenetic meaning including the question of possible autoimmune mechanisms is discussed.

Acquired Immunodeficiency Syndrome↗

T cells in B-cell chronic lymphocytic leukemia: quantitative assessment of cytotoxic and interleukin-2-producing lymphocyte precursors by limiting dilution analysis.

Controversy exists as to the functional capacity of T lymphocytes in patients with B-cell chronic lymphocytic leukemia (CLL). We have used a limiting dilution (LD) culture approach to quantitatively assess frequencies of proliferating lymphocyte precursors (PLP), cytotoxic lymphocyte precursors (CLP), and interleukin-2 (IL-2)-producing helper lymphocyte precursors (HLP). Unseparated mononuclear cells (MNC) or purified T cells (E+) and leukemic B cells (E-) were cocultured under LD conditions with irradiated OKT3 hybridoma cells in the absence (determination of HLP) or presence of recombinant IL-2 (determination of PLP and CLP). Under these conditions, low frequencies of PLP, HLP, and CLP (f = 1/65 to 1/4600) were measured in unseparated MNC of CLL patients. In contrast, purified T cells (50% to 92% CD3+) contained precursors of proliferating, IL-2-producing and cytotoxic T cells in similar frequency as did T cells from healthy control donors (f = 1/4 to 1/24). Leukemic B cells rigorously depleted of T cells did not give rise to measurable frequencies of PLP, HLP, or CLP (f less than 1/50.000) except in one CLL patient where a significant frequency (f = 1/1700) of HLP was consistently present in E- cells, despite the absence of growth-inducible PLP and CLP. Taken together, these results indicate that comparable numbers of IL-2-producing helper T cells and cytotoxic T cells are present in B-CLL patients and healthy controls, respectively. The data are discussed with respect to reported T cell abnormalities in B-CLL.

Cell Differentiation↗

[Lymphocyte subpopulations in patients with skin basalioma of the trunk].

In 11 male patients with histologically proven basal cell epithelioma of the trunk, we studied the distribution of peripheral lymphocyte subsets. All of the patients revealed pathological T-cell subsets, 6 of them showing reduced numbers of CD8 and 5 decreased numbers of CD 4 cells. 2 patients had taken arsenic; in 2 patients we diagnosed a further tumor of some other origin.

Adult↗

Flow-cytometric detection of human anti-rat insulinoma antibodies in relation to anti-human islet cell and anti-insulin antibodies. Recognition of distinct antigens by antibodies in early type I diabetes.

Flow cytometry was recently introduced for the detection of antibodies in human serum to a cultured insulin-secreting rat insulinoma cell line (RINm5F) to investigate humoral immune reactivity in newly diagnosed type I (insulin-dependent) diabetic patients. Fifty-three patients were observed for 6-20 mo after clinical onset of diabetes with a reported duration of symptoms of less than 6 wk. Human anti-RINm5F antibodies were detected in 28%, human anti-islet cell antibodies in 62%, and anti-insulin autoantibodies in 36% of patients before initiation of insulin therapy. Occurrence of human anti-RINm5F antibodies at this stage was correlated with human anti-insulin autoantibodies rather than with the formation of anti-islet cell antibodies. Incidence of anti-RINm5F antibodies in individuals with duration of diabetes greater than 6 wk was 38%, whereas human anti-islet cell antibodies and anti-insulin antibodies became detectable in 72 and 61% of the patients, respectively. These findings are in line with previous reports of immunoprecipitation by human diabetic serums of a 64,000-Mr antigenic structure in freshly prepared rat islet cells. The results suggest a reactivity of distinct classes of antibodies in serums of patients with type I diabetes to disparate antigens on human islet cells and cloned rat insulinoma cells and, moreover, reactivity to insulin as the secreted product. Further characterization of the reacting RINm5F antigens and prospective studies in subjects at risk for diabetes are required to validate the application of RIN cells to the investigation of immune mechanisms involved in the pathogenesis of human type I diabetes.

Adenoma, Islet Cell↗

Comparison of clinical efficacy and toxicity of conventional and optimum biological response modifying doses of interferon alpha-2C in the treatment of hairy cell leukemia: a retrospective analysis of 39 patients.

Hairy cell leukemia (HCL) has been shown to be extraordinarily sensitive to treatment with alpha-interferon (IFN). In order to define clinically effective IFN doses associated with minimal toxicity, the therapeutic efficacy and side effects of recombinant IFN-alpha-2C treatment of HCL were compared for two different dose regimens: 18 patients (group A) received conventional doses of recombinant IFN-alpha-2C (2 x 10(6)U/m2) for a median time of 35 weeks (range 26-52 weeks), and 21 patients (group B) received optimum biological response-modifying doses of IFN-alpha-2C (0.2-0.6 x 10(6)U/m2) for a median time of 31 weeks (range 12-52 weeks). Interferon was administered daily subcutaneously for 3 months and then every second or third day. Induction of neopterin excretion was chosen as the marker for definition of biological response. The smallest IFN dose causing maximum in vivo induction of biosynthesis of the GTP-degradation product neopterin was deemed "biologically optimal." Both dose regimens were effective, but the low-dose regimen was almost free of toxicity. Thus, in HCL patients alpha-IFN related toxicity can be separated from its antineoplastic activity. Low doses of alpha-IFN should be considered for treatment of HCL patients who develop toxic side effects and for primary treatment of HCL patients with severe cytopenia.

Adult↗

B cell maturation in chronic lymphocytic leukemia. III. Effect of recombinant cytokines on leukemic B cell proliferation.

Proliferation and differentiation of B lymphocytes is influenced by a variety of soluble mediators. The recent cloning of various cytokines has made it possible to study the effect of molecularly defined lymphokines and other cytokines on B-cell activation. In the present study, we have analyzed the effect of several cytokines on the in vitro proliferation of highly purified leukemic B cells from patients with chronic lymphocytic leukemia (CLL). The recombinant human cytokines tested included interleukins 1, 2, 3, and 4 tumor necrosis factor-alpha (TNF-alpha) and interferon-alpha (IFN alpha), all of which are known to play a role in B-cell activation. B cells from 10 of 13 patients (all with white blood cell counts greater than 100,000/ul) did not respond to any of the cytokines tested. In contrast, B cells from 3 other patients responded well to IL-2 when preactivated for 24 h with phorbolester TPA and ionomycin. Moreover, preactivated B cells from 2 of these patients also proliferated in response to TNF-alpha, and some proliferation of unactivated B cells in response to TNF-alpha was seen in one case. Together, these results stress the clonal heterogeneity of CLL B-cell populations, and demonstrate that both IL-2 and TNF-alpha may act as a B-cell growth factor on B cells from certain CLL patients.

B-Lymphocytes↗

Cell-mediated autoimmunity at the onset of insulin-dependent diabetes mellitus (IDDM).

Peripheral blood lymphocytes have been investigated in 20 newly diagnosed type-I diabetics and 10 healthy subjects using monoclonal antibodies. Mononuclear cells were marked with anti-T-lymphocytes (Leu2, 3, 4, 12) and anti-Ia-antibodies (K14, L243) using indirect immunofluorescence. The percentage of circulating K14- and L243-positive cells was significantly higher in all diabetics than in normal controls. An increase in the number of K14-bearing cells was found in newly diagnosed patients with duration of less than 7 days (n = 10) compared with diabetics of longer duration (1 to 8 months; n = 10). Using dual-color immunofluorescence with fluorescein-conjugated anti-T-lymphocytes and rhodamin-conjugated anti-Ia-antibodies it was not possible to identify Ia-antigen bearing cells (Ia cells) as helper or suppressor lymphocytes. In addition, there was no significant difference in the number of Ia cells in diabetics with and without islet cell antibodies. It is concluded that there is evidence of activation of cellular immune response in type I diabetes, particularly in the early days of manifestation. However, previous assumptions that Ia cells represent T-cell activation have to be questioned.

Adolescent↗

Dose-response relationship in the treatment of idiopathic thrombocytopenic purpura with intravenous immunoglobulin.

The dose-response relationship in the intravenous immunoglobulin treatment of idiopathic thrombocytopenic purpura was studied in 20 adult patients in a multicenter prospective crossover trial. The rate of response increases from 3 out of 11 (27%) to 6 out of 10 treatment periods (60%) by raising the 7S-IgG dose given on 5 consecutive days from 164.50 +/- 24.55 to 359.65 +/- 58.62 mg/kg body weight. The onset and duration of response as well as the peak platelet count were found to be independent of the doses. A long-term benefit induced by intravenous immunoglobulin treatment could be achieved in 2 out of 14 patients with chronic idiopathic thrombocytopenic purpura.

Adolescent↗

B cell maturation in chronic lymphocytic leukemia. II. Clonal heterogeneity in the response to various B cell activators and recombinant cytokines (rIFN-gamma, rIFN-alpha, rIL2).

Maturation of B cells into immunoglobulin (Ig)-secreting cells is influenced by antigen-nonspecific growth and differentiation factors. In the present study, we have analyzed the effect of several recombinant cytokines (rIL2, rIFN-alpha, rIFN-gamma) on the terminal differentiation of B cells from 10 patients with chronic lymphocytic leukemia (CLL) stimulated with three different B cell activators (phorbolester TPA, staphylococcus aureus Cowan I bacteria, or pokeweed mitogen). Secretion of IgM, as determined by heavy-chain specific ELISA, varied widely among different CLL cell populations, but was induced in all cases by one or several of these activators. Importantly, this response was enhanced 2-10-fold in all patients by at least one of the tested recombinant cytokines alone, or a combination of rIL2 with rIFN-alpha or rIFN-gamma. The results illustrate the clonal heterogeneity of CLL B cell maturation in vitro and demonstrate that rIL2, rIFN-alpha or rIFN-gamma can act as a B cell differentiation factor, depending on the responsiveness (stage of differentiation) of the individual clonal B cell population.

B-Lymphocytes↗

[Comparison of CHOP and COP-BLAM chemotherapy in highly malignant non-Hodgkin's lymphoma].

The course of disease in 61 consecutive patients with non-Hodgkin lymphoma of high grade malignancy, treated between 1979 and 1985 with either CHOP or COP-BLAM regimen, was analysed retrospectively. Both groups showed a highly similar distribution of prognostic variables. COP-BLAM treatment resulted in significantly more complete remissions (23 of 27) than CHOP (11 of 29, P = 0.001). Life expectancy was, therefore, considerably higher in the COP-BLAM treated group. The mean observation period, however, was longer for CHOP-treated patients (37 vs. 30 months. The higher remission rate of the COP-BLAM regimen was not compromised by a substantial increase in toxicity; no therapy-related death was observed. Thus, the COP-BLAM regimen appears to be superior in inducing complete remissions in aggressive non-Hodgkin lymphoma. Actual survival curves suggest that this corresponds to an increased proportion of cured patients, but longer follow-ups are needed.

Antineoplastic Combined Chemotherapy Protocols↗

Complement and HLA. Further definition of high-risk haplotypes in insulin-dependent diabetes.

The families of 41 probands with type I (insulin-dependent) diabetes mellitus (IDDM) were typed for HLA-A, HLA-B, and HLA-DR antigens in addition to the complement polymorphisms C2, C4A, C4B, and Bf. All of these loci are encoded on the short arm of human chromosome 6 in a narrow region. Alleles at HLA-B (8, 15, 18, and 40), HLA-DR (3 and 4), and Bf (F1) have been associated with increased relative risk (RR) for IDDM, while HLA-B7 and HLA-DR2 have been associated with decreased RR for IDDM. This study confirms those significant risks in addition to confirming increased risk for the null (silent) allele for C4A (C4AQ0) and a rare C4B variant (C4B2.9). The significantly associated antigens (alleles) and risks were: HLA-B8 (RR = 3.1), HLA-DR3 (RR = 5.2), HLA-DR4 (RR = 4.3), and BfF1 (RR = 7.1), in addition to C4AQ0 (RR = 2.8) and C4B2.9 (RR = 12.6). Significantly low risk was associated only with HLA-DR2 (RR = 0.1). In a recent study, we defined five high-risk haplotypes that were determined solely by HLA-B, Bf, and HLA-DR (B8-BfS-DR3, B8-BfS-DR4, B15-BfS-DR4, B18-BfF1-DR3, and B40-BfS-DR4). By inclusion of information from the complement polymorphism, we have defined in greater detail three of these five high-risk haplotypes. One previously identified haplotype (B40-BfS-DR4) showed no complement clustering, while the rare high-risk haplotype (B8-BfS-DR4) was seen only once in this smaller sample.(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗

In vitro maturation of B cells in chronic lymphocytic leukemia. I. Synergistic action of phorbol ester and interleukin 2 in the induction of Tac antigen expression and interleukin 2 responsiveness in leukemic B cells.

Recent evidence indicates that interleukin 2 (IL 2), formerly thought to serve as growth factor exclusively for activated T cells, is directly involved in human B cell differentiation. We have investigated the role of IL 2 and IL 2 receptors (as defined by monoclonal anti-Tac antibody) in the phorbol ester-induced in vitro maturation of leukemic B cells from patients with chronic lymphocytic leukemia (CLL). Peripheral blood lymphocytes from B cells from CLL patients with high (greater than 10(5)/microliters) white blood cell counts were depleted of residual T lymphocytes and low-density cells (primarily macrophages) by consecutive steps of E rosetting, complement-mediated lysis of OKT3+ and OKT4+ cells, and Percoll density gradient centrifugation. No OKT3+ T cells were detectable in these cell populations before or after culture. When incubated for 3 days with phorbol ester plus recombinant human IL 2 (rIL 2), 12 to 57% of highly purified B cells from four of five tested patients expressed Tac antigen. Both phorbol ester and rIL 2 were required for maximal Tac antigen expression. Functional studies revealed that phorbol ester-activated (but not resting) CLL B cells responded to rIL 2 with [3H]thymidine incorporation and with enhanced secretion of IgM. Tac+ B cells were isolated in two cases on a fluorescence-activated cell sorter. In one patient, stimulation of Tac+ B cells with rIL 2 resulted in enhanced [3H]thymidine incorporation but no change in IgM secretion, as compared with Tac- B cells; in the second patient, stimulation of Tac+ B cells with rIL 2 did not result in [3H]thymidine uptake, but did result in significant IgM secretion. These findings indicate that certain leukemic B lymphocytes can be induced to express IL 2 receptors and respond to IL 2. The use of resting clonal B cell populations arrested at distinct stages of differentiation may help to better define the stage(s) at which IL 2 acts directly on B cells to induce proliferation and/or terminal differentiation.

Antibodies, Monoclonal↗

[Results of a phase II study on the treatment of hairy cell leukemias with various doses of alpha-2-recombinant interferon].

Hairy-cell leukemia has been shown to be extraordinary sensitive to treatment with alpha-interferon. In order to define clinically effective interferon doses associated with minimal toxicity two different dose regimens were applied in this clinical trial: firstly, a conventional dose schedule, and secondly, a biologically defined dose regimen. For dose finding in the latter group, neopterin, a GTP degradation product produced by macrophages under control of interferon, was chosen. Six patients (Group A) received conventional doses of recombinant interferon--alpha-2 (rIFN-alpha-2) 3 X 10(6) U/sqm/daily by the subcutaneous route. Five patients (Group B) were treated with the minimal dose of rIFN-alpha-2 which had previously been shown to induce maximum neopterin levels in urine. Already interferon doses in the range of 3 to 5 X 10(5) U/sqm2/daily administered subcutaneously proved to be sufficient for triggering maximum neopterin excretion in the urine. After six months of interferon treatment all patients were evaluable. At this time both doses regimens proved to be effective in terms of their anti-leukemic activity, but differed significantly in toxicity, which was only seen in Group A patients.

Adult↗

C4 polymorphism in the dog: molecular heterogeneity of the C4 alpha and C4 gamma subunit chains.

Using an immunoblotting technique and goat antihuman C4, we observed five distinct electrophoretic variants of C4 in a panel of 60 random dogs. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of immunoprecipitated C4 showed that dog C4 is composed of three polypeptide subunit chains (alpha, beta, and gamma) and that structural variability occurs within the alpha- and gamma-chain regions. Two distinct molecular weight forms of both the C4 alpha- (alpha A and alpha B) and C4 gamma- (gamma A and gamma B) chain were detected. The variant forms of C4 alpha and C4 gamma were found in association with particular C4 allotypes.

Animals↗

HLA-linked complement markers in Alzheimer's and Parkinson's disease: C4 variant (C4B2) a possible marker for senile dementia of the Alzheimer type.

We determined the gene frequencies for the alleles of the HLA-linked complement markers C2, properdin factor B (BF), C4A (Rodgers) and C4B (Chido), and the red cell enzyme glyoxalase-I in 38 unrelated patients with senile dementia of the Alzheimer type, 42 patients with idiopathic Parkinson's disease, and 59 unaffected, aged-matched control blood donors. In senile dementia of the Alzheimer type and in Parkinson's disease, no significant difference was found in the gene frequencies of alleles at either the BF, C2, or GLO-I locus compared with those of age-matched controls. In senile dementia of the Alzheimer type, a striking increase in the frequency of the rare C4B locus allele, C4*B2, was apparent, resulting in the high relative risk of RR = 8.8 (p less than 0.0001) for this disorder.

Alleles↗