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Tumor specific peptides recognized by T lymphocytes infiltrating solid tumors, as well as the corresponding T cell receptor (TcR) repertoire usage, have been extensively investigated. By contrast, tumor infiltrating B cells and their immunoglobulin (Ig) repertoire have been studied only in a limited number of tumors. The objective of the present study was to determine, whether DNA sequence analysis of the expressed immunoglobulin variable regions of B cells that infiltrate breast cancer, could be used to reveal a potential specific tumor binding capacity of the antibodies. To answer this question, about 200 expressed Ig heavy (VH) and light chain variable gene (VL) regions were cloned, sequenced and comparatively analysed from a typical medullary beast carcinoma (MBC), where the massive B and plasma cell infiltration correlates with favourable prognosis despite of its high grade. The tumor infiltrating B cell Ig heavy and light chain sequences could be classified into clusters, families and subgroups, based on the identity level to germline, showing a pattern of oligoclonality. Some overrepresented clusters could be determined. In the course of a detailed analysis and search in Blastn database, a number of VH and VL sequences showed more than 99% homology to DNA sequences of Ig VH region, with proved tumor antigen binding capacity. Our data suggest, that potential tumor binder Ig VH and VL sequences might be selected using a detailed immunoglobulin variable region analysis. This new approach might have a benefit for further antibody engineering, as difficulties in search for tumor binders by phage library selection might be reduced and the time for selection shortened.

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A number of cases of unexplained (idiopathic) recurrent spontaneous abortions may be attributable to immunological mechanisms. Several lines of evidence indicate that some immunocompetent effector cell populations play an important role in the pathogenesis of unexplained miscarriages. However a suitable method is lacking for defining an existing immunological background of recurrent spontaneous abortions. We tried to find a useful cellular immunological method, that is suitable for predicting the eventual immunological cause in the case of unexplained recurrent spontaneous abortions. We have examined the anti-paternal cytotoxic T-lymphocyte precursor frequencies by cell-mediated lympholysis and limiting dilution analysis in the peripheral blood of women with recurrent spontaneous abortions in order to reveal the functional role of this cell population in spontaneous abortions. An extremely high partner allo-antigen-specific cytotoxic T-lymphocyte precursor frequency was determined in the case of all those habitual aborters, where no other than an immunological cause could be responsible for the abortions. This phenomenon supports the important role of the T-lymphocytes in this disorder. We suggest that the immunological background of recurrent spontaneous miscarriages might be determined on the basis of a very high cytotoxic T-lymphocyte precursor frequency. This diagnostic test might be useful in selecting patients for immunotherapy.

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Authors report here on a case presenting as B-CLL and complicated with cutaneous infiltration involving the legs and the trunk a year later. Immunohistochemic analysis and the immunoglobulin heavy chain gene rearrangement confirmed cell invasion into the skin identical with the underlying disorder. After failure of conventional chemotherapy, interferon alpha 2b therapy has been started with satisfactory result. Few cases presenting cutaneous infiltration in the course of B-CLL has already been reported in the literature. Secondary cutaneous B-cell lymphoma represents an entity of the poorest prognosis in comparison with primary cutaneous form treated with conventional therapy as well as with lymphomas lacking skin manifestations. Interferon alpha 2b therapy cleans up the skin and yields a favourable survival so it's introduction recommended in this entity. Authors summarise the characteristics of secondary cutaneous B-cell lymphomas on the basis of literature survey. According to authors investigations histidine decarboxylase activity was found to be absent from the lymphocytes infiltrating the skin in contrast to those remaining in the circulation. This seems to be a newly recognised feature of these cells. The changing character of the disease raises the possibility of an altered gene expression pattern of the cells invading the skin. Authors summarise data from the literature concerning suspected molecular mechanism of tissue invasion.

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We describe a patient presenting with B cell chronic lymphocytic leukemia (B-CLL) who subsequently developed cutaneous infiltrates. Specimens of the blood, bone marrow and cutaneous infiltrations all showed the same heavy-chain gene rearrangement. Following failure of conventional chemotherapy, and in view of the similarity of the disease to cutaneous T cell lymphoma, interferon-alpha therapy was employed with satisfactory results. Introduction of this cytokine to the therapeutic modalities for secondary cutaneous B-CLL would hopefully change the poor outcome of this entity, or at least could produce a better quality of life. Loss of histidine decarboxylase activity in the infiltrating cells - in contrast to circulating lymphocytes - may be associated with the transformation of B-CLL to a more aggressive infiltrative form, offering a possible explanation for tissue invasiveness. The changing character of the disease raises the possibility of a second mutational event in the course of B-CLL.

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Breast medullary carcinoma are heavily infiltrated by B-lymphocytes and associated with a good prognosis despite their high histological grade. We investigated the Ig repertoire of B-lymphocytes infiltrating one such tumour. A single cell suspension was obtained from a tumor specimen by enzymatic digestion. VH, Vkappa, and Vlambda regions were amplified by RT-PCR using mixtures of primers optimized to maximize the diversity of the PCR products. They were then cloned and sequenced. Analysis of 9 VH, 5 Vkappa, and 10 Vlambda sequences using the Kabat database indicated that several VH and VL region subgroups (I, II and III) are expressed by B-lymphocytes infiltrating this tumor. The analysis of CDR3 regions also showed a variability, although some VH and VL clones exhibited identical or nearly identical sequences. Thus, the B-cell infiltration observed in this breast medullary carcinoma does not reflect a monoclonal proliferation and represents an oligoclonal or a polyclonal B-cell proliferation.

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The peripheral blood mononuclear cells of patients with infectious mononucleosis (IM) have been characterized by the determination of activation antigens using a panel of 11 monoclonal antibodies (MoAbs) belonging to 9 clusters. The activation of CD8+ peripheral blood mononuclear cells of IM patients was found to be determined by HLA-DR and CD45RO MoAbs. The antibodies of the CD30, CD40 and CD70 termed antigens also showed an increased expression as compared to the controls. In contrast, the CD25, CD69, CD71, and CD45 antigens were expressed at a low rate on the surface of the CD8+ cells. We found, on the other hand, a very low percentage of B lymphocytes in the peripheral blood, which reflects on the virus caused antigen modulation and on the effectivity of activated CD8 cells with the characteristic expression of the above outlined markers in IM. In six asymptomatic patients, the percentage of CD8+HLA-DR+, as well as of CD8+CD45RO+ cells proved to be lower than that in the active phase of the disease. The number of B cells showed normal value in the clinically asymptomatic cases.

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Recently we presented evidence that cellular immune responses are associated with increased in-vitro and in-vivo excretion of neopterin (Huber et al., 1983) and that, in vitro at least, macrophages and IFN-gamma play a key role in the induction of this phenomenon (Huber et al., 1984). Although this marker is increasingly applied for monitoring of human disease, there is limited knowledge about the mechanism(s) responsible for its increased biosynthesis during inflammatory states. To further elucidate this question we evaluated neopterin and IFN-levels in culture supernatants of human blood cells and in patients' sera. Cells or patients were exposed to a panel of recombinant cytokines, alloantigens or lipopolysaccharide. To investigate indirect stimulation by induction of production of endogenous IFNs, the impact of neutralization of IFNs by addition of specific antibodies was also studied. The data confirm our previous results which identified the monocyte/macrophage as the main producer cell among human blood cells. They further demonstrate that, at least in vitro, IFN-gamma, IFN-alpha and LPS can all stimulate neopterin release independently from each other. Thirdly, they indicate that stimuli such as alloantigens or TNF-alpha can indirectly enhance neopterin release by their capacity to induce production of endogenous IFN-gamma. On the basis of these data we conclude that enhanced neopterin biosynthesis does not necessarily relate to activation of T cells but can also be caused by non-immune stimuli.

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The effects of alpha- and gamma-interferons (IFN-alpha, -gamma) and of interleukin 2 (IL-2) on the expression of certain differentiation antigens were compared with those of major histocompatibility antigens on human lymphocytes. IFN-gamma and IFN-alpha in high doses significantly increased the expression of T11 (CD2) differentiation antigen, but did not affect the expression of T4 (CD4), T8 (CD8), T3 (CD3) and Leu-7 antigens (HNK-1). Both natural and recombinant IFN-alpha and -beta apparently increased the expression of HLA-ABC antigens and of beta-2 microglobulin (beta 2m) after 16 h incubation. The amount of HLA-DR antigen, however, doubled in a few hours following IFN-gamma treatment. IL-2 affected the expression of CD2 and CD8 antigens only marginally, but did not affect that of CD3 and Leu-7; however, it strongly enhanced the expression of HLA-ABC, HLA-DR, and beta 2m antigens.

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This study was undertaken to define immune responses induced by leukocyte and platelet transfusions. We offer evidence that activation by alloimmunization with intravenously administered "buffy coat" cells results in immune alterations similar to the early rejection episodes following kidney transplantation. Thus, IL-2 and HLA-DR expression increased on PBL 2 and 3 days after antigen exposure and paralleled elevations of IFN-gamma, neopterin, and beta 2 microglobulin levels. No significant changes were detected in the number of T-cell subpopulations. Alloimmunization by purified platelets alone that express only class I MHC antigens failed to induce the above alteration, even after repeated exposure. Repeated alloimmunization with "buffy coat" cells or isolated platelets stimulated a progressive increase up to 100% blocking activity on EA rosette formation. We conclude that the expression of activation markers on PBL and the production of IFN gamma and neopterin reflect the early phase of alloimmune response induced by leukocytes. This type of alloactivation is not a prerequisite for the development of FcR-blocking antibody, which is produced after pure platelet transfusion as well.

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The role of cytokines in the control of beta-2 microglobulin release from various haemopoietic cells was studied in vitro. Cell types investigated were resting cells or blasts of the T cell, B cell or monocyte-macrophage lineage. Mediators used in these experiments were r-IFN-alpha 2c, r-IFN-gamma, r-TNF-alpha, r-TNF-beta, r-IL1, r-IL2 and r-GM-CSF. Nanogram amounts of some of these mediators strongly affected beta-2 microglobulin release in vitro. r-IFN-gamma, r-IFN-alpha 2c and r-IL2 strongly enhanced and r-TNF-alpha and r-TNF-beta occasionally increased shedding of beta-2 microglobulin. r-IL1 and high concentrations of r-IFN-alpha 2c were inhibitory, whereas r-GM-CSF was ineffective. The impact of antigenic stimulation on beta-2 microglobulin release in mixed lymphocyte culture (MLC) was also studied. Stimulation with alloantigens in MLC greatly enhanced beta-2 microglobulin shedding, and this enhancement could be inhibited by a monoclonal antibody neutralizing human IFN-gamma. Among the various cell types studied, macrophages derived from peripheral blood monocytes were most susceptible to cytokine-induced alterations of beta-2 microglobulin shedding. From these data, we conclude that cytokines not only control the static expression of beta-2 microglobulin on the surface of haemopoietic cells but also largely affect their shedding.

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The influence of in vivo application of recombinant interferon-alpha 2c (IFN-alpha 2c) and recombinant interferon-gamma (IFN-gamma) on beta-2 microglobulin levels was studied in eight patients with chronic myelogenous leukaemia or advanced renal cell carcinoma. Data indicated enhanced beta-2 microglobulin biosynthesis in close temporary association with injection of both types of interferons. The influence of in vivo stimulation by allogenic leukocytes and the influence of renal allografts or cytomegalovirus infection on serum beta-2 microglobulin and IFN-gamma levels were also studied. Increased beta-2 microglobulin concentrations were observed again in each of these clinical situations and were closely associated with enhanced endogenous interferon production. From these in vivo data and the in vitro data presented in the preceding publication, (1) we conclude that endogenous interferon levels are crucial for the regulation of beta-2 microglobulin release in vivo.

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The functional importance of various cell membrane bound molecules was studied and compared in the NK cytotoxicity and CTL activity. LFA-1 and CD2 participate in both killing functions, while CD3 and CD8/CD4 as well as MHC class I molecules are involved only in CTL activity. Nevertheless CD2- and beta 2-microglobulin are representatives of the NK function. It was demonstrated that CD2-, LFA-1 and beta 2-microglobulin molecules have an additive and complementary function in the killing mechanism. The upregulation of alpha- and gamma-interferons on NK function seems not to be a consequence of the enhanced expression of these molecules on the cell surface induced by IF at the same time.

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