bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hepatitis B core antigen-specific IFN-gamma production of peripheral blood mononuclear cells in patients with chronic hepatitis B virus infection.
Authors: Inoue M , Kakumu S , Yoshioka K , Tsutsumi Y , Wakita T , Arao M 
Published: December 2022

Abstract
To evaluate the specificity of cellular immune response to hepatitis B virus (HBV) Ag in patients with chronic HBV infection, we have measured IFN-gamma production and proliferation of PBMC of 16 patients with chronic active hepatitis (CAH), 17 asymptomatic carriers of HBV (ASC), 6 anti-hepatitis B surface (HBs)-positive subjects, and 6 control individuals with ELISA procedure and [3H]thymidine incorporation. There was no significant increase in the mean proliferative response to recombinant HB surface and core Ag (rHBsAg and rHBcAg), nor was IFN-gamma production elicited with rHBsAg in any group. In contrast, PBMC of HBeAg-positive and anti-HBe-positive CAH patients, and anti-hepatitis B "e" Ag (HBe)-positive ASC showed significantly enhanced IFN-gamma production in response to HBcAg, whereas those of HBeAg-positive ASC and anti-HBs-positive subjects did not respond to HBcAg. The maximal response was observed in a 5-day culture with 500 ng/ml of rHBcAg when assessed by stimulation index value. Monocytes did not demonstrate an increased suppressor or helper activity for IFN-gamma production in these patients. T cell subset fractionation revealed that CD4+ cells were main population of IFN-gamma production specific for HBcAg and CD8+ cells did not suppress IFN-gamma production of CD4+ cells. Furthermore, CD4+ cells of HBeAg-positive ASC generated lesser amounts of IFN-gamma than HBeAg-positive CAH patients did. These results show that the measurement of IFN-gamma production is useful to determine cellular immune response to HBV Ag and suggest that IFN-gamma production depends on the helper activity of CD4+ T cells sensitized to HBcAg.
Activation of human cytolytic cells through CD2/T11. Comparison of the requirements for the induction and direction of lysis of tumor targets by T cells and NK cells.
Authors: Scott C F , Bolender S , McIntyre G D , Holldack J , Lambert J M , Venkatesh Y P , Morimoto C , Ritz J , Schlossman S F 
Published: December 2022

Abstract
We studied the mechanisms whereby human T cells and NK cells are activated and directed to lyse tumor targets through the CD2 (T11/E-rosette) Ag. Using two cloned NK lines, we showed that these cells, as had previously been shown for T cells, could be directed to lyse an "NK-resistant" tumor target in the presence of antibody heterodimers. These heterodimers consisted of a (mAb) to CD2 (anti-T11(2) or anti-T11(3] linked to a mAb recognizing the tumor cell (J5, anti-CALLA). However, distinct differences between NK cells and T cells were observed with regard to the requirements for such directed lysis: first, only one epitope of CD2 on NK cells (either T11(2) or T11(3] needed to be recognized by the antibody heterodimer in order for directed lysis to occur, whereas for T cells both T11(2) and T11(3) epitopes had to be recognized. Second, in confirmation of previous data with monomeric anti-T11(2) or anti-T11(3) antibody, heterodimers constructed with these reagents enhanced conjugate formation between NK cells and tumor targets, whereas no such enhancement was seen with T cells. All types of heterodimer directed lysis were dependent on the adhesion molecule LFA-1, as an anti-LFA-1 antibody-blocked lysis. Third, whereas in T cells lysis mediated through CD2 appeared to be regulated by CD3 but not vice versa, all types of lysis by NK cells appeared to be regulated through CD2. Finally we showed that F(ab')2 fragments of the anti-T11(2) and anti-T11(3) antibodies could activate NK cells, but were unable to activate T cells either as cloned cytolytic lines, or in populations of PBL. The implications of our findings with regard to the role of CD2 in the activation of cytolytic cells is discussed.
Regulation of MHC expression in vivo. II. IFN-alpha/beta inducers and recombinant IFN-alpha modulate MHC antigen expression in mouse tissues.
Authors: Halloran P F , Urmson J , Van der Meide P H , Autenried P 
Published: December 2022

Abstract
We examined the effect of type I IFN inducers and rIFN-alpha on MHC expression in mouse tissues in vivo. MHC expression was assessed in a radiolabeled mAb binding assay and by indirect immunoperoxidase staining of tissue sections. polyI:C, an inducer of IFN-alpha/beta, induced large increases in class I MHC in many tissues, with little effect on class II expression. In the kidney, which was studied in detail, polyI:C increased class I expression from day 1 to day 6, localized in glomeruli, tubules, and arterial endothelium. Renal class II MHC was less affected but tended to be decreased at days 3 to 6, corresponding to diminished staining of class II-positive interstitial cells. polyI:C increased renal class I MHC in nude mice and mice with severe combined immunodeficiency, and in mice treated with cyclosporine or mAb against IFN-gamma. The effects of influenza virus resembled those of polyI:C. However, a potent T cell stimulus, allogeneic ascites tumor cells, induced markedly different MHC changes, with massive and sustained increases in class I and II, presumably due to IFN-gamma release, which was inhibited by cyclosporine or by mAb against IFN-gamma. The effect of polyI:C was largely simulated by rIFN-alpha, whereas the effect of allogeneic cells was simulated by rIFN-gamma. Thus, rIFN-alpha and its inducers in vivo produce a sustained increase in renal class I expression in kidney and other tissues, sometimes with changes in class II expression. Such effects could be relevant to the immune modulatory actions of IFN, and to the immunologic consequences of viral infections.
IL-6 is an intermediate in IL-1-induced thymocyte proliferation.
Authors: Helle M , Boeije L , Aarden L A 
Published: December 2022

Abstract
Both IL-1 and IL-6 have been shown to be comitogenic for lectin-stimulated thymocytes. Thymocytes cultured in the presence of IL-1 produce IL-6 themselves. This IL-6 production is caused by a cell population with low buoyant density. After removal of these cells, IL-6 or IL-2 are still co-mitogenic for thymocytes whereas IL-1 is not. Addition of IL-1 to such thymocytes renders them about 100-fold more sensitive to IL-6. At all conditions proliferation is inhibitable with antibodies to IL-2 and to the IL-2R. Our experiments show that IL-1-driven proliferation of thymocytes is dependent on endogenous IL-6 production and that in the classical thymocyte assay IL-1 has a dual role: it induces IL-6 production and it greatly increases the sensitivity for IL-6.
Arachidonic acid mobilization and phosphoinositide turnover by the terminal complement complex, C5b-9, in rat oligodendrocyte x C6 glioma cell hybrids.
Authors: Shirazi Y , McMorris F A , Shin M L 
Published: December 2022

Abstract
Previously, we have shown that rat oligodendrocytes release phospholipid and generate arachidonic acid (AA) and leukotriene B4 in response to sublytic C5b-9 formation. In the present study, we investigated the biochemical pathways by which C5b-9 generates AA from clone ROC-1, a fusion product of rat oligodendrocytes and C6 glioma. Cells were incubated for 24 h in the presence of [3H]AA or [3H]myoinositol. They were then sensitized with antibody against hybrid cell stroma and treated for 1 h with C9-depleted human serum (C9D-HS) or C9D-HS reconstituted with C9. Alternatively, cells were treated with C8,C9D-HS or C8,C9D-HS reconstituted with C8 or C8 plus C9 for 1 h. Qualitative and quantitative analysis of the released [3H]AA and [3H]myoinositol radiolabeled products were performed by thin layer chromatography/autoradiography and anion exchange chromatography, respectively. The major [3H]AA radiolabeled products after C5b-9 stimulation comigrated with intact phospholipid and AA standards, and the major [3H]myoinositol radiolabeled product was inositol-1-phosphate. Treatment of cells with phospholipase A2 inhibitors, mepacrine and bromophenacyl bromide, abolished AA release by C5b-9. In the absence of extracellular Ca2+, C5b-9 also failed to induce the release of AA. Interestingly, 1-(5-isoquinolinsulfonyl)-2-methylpiperazine (H-7), a potent inhibitor of protein kinases, inhibited AA release by C5b-9, whereas AA release stimulated by the calcium ionophore A23187 was not blocked by H-7. The results suggest that AA generation by C5b-9 from the ROC-1 clone involves activation of Ca2+-dependent phospholipase A2 which is regulated by protein kinase-dependent mechanisms.
Analysis of VH gene replacement events in a B cell lymphoma.
Authors: Kleinfield R W , Weigert M G 
Published: December 2022

Abstract
We have analyzed a series of recombinational events at the IgH chain locus of the B cell lymphoma, NFS-5. Each of these recombinational events results in the replacement of the VH gene segment of the rearranged H chain gene (VhDJh) with that of an upstream germline gene segment. Replacements on the productive and nonproductive alleles have been observed. In each case, the recombination occurs in close proximity to a highly conserved heptameric sequence (5'TACTGTG3') which is located at the 3' end of the VH coding region. In the two examples of recombination on the productive allele that have been analyzed, the initial VHQ52 gene is replaced by different VH7183 genes. On the non-productive allele, sequential replacement events have been analyzed: the initial VHQ52 rearrangement is first replaced by a closely related VHQ52 gene, followed by a second replacement using a VHQ52 pseudogene. Southern blot analysis using VH probes indicates that these recombinations may be accompanied by the deletion of germline VH genes belonging to both the VHQ52 and VH7183 families, suggesting that these gene families are interspersed in the NFS/N mouse.
Generation of T cell repertoire. Two distinct mechanisms for generation of T suppressor cells, T helper cells, and T augmenting cells.
Authors: Asano Y , Tada T 
Published: December 2022

Abstract
The present studies were carried out to characterize the influence of the T cell maturation environment on a repertoire of Th cells, T augmenting cells, and Ts cells, which were shown to construct a minimal regulatory circuit to regulate a helper function of class II-restricted Th cells. A repertoire of keyhole limpet hemocyanin-specific Th cells was influenced predominantly by I-A molecules of the T cell maturation environment, whereas a repertoire of T augmenting cells was determined by both I-A and I-E molecules. These repertoires were not influenced by the priming with Ag. A repertoire of Ts cell factor-producing Ts cells was not influenced by the T cell maturation environment, but rather was determined by the I-J haplotype of the APC utilized for priming with Ag. In contrast, a repertoire of novel cognate type Ts cells, which inhibit class II-restricted Th cell function in a restriction-restricted manner, was influenced by both I-A and I-E molecules of the T cell maturation environment. These results demonstrate the two distinct mechanisms for generating a T cell repertoire: a selection by class II molecules of the T cell maturation environment before the priming with foreign Ag and a selection by priming with APC and Ag.
Generation of somatic variants of a B cell hybrid mediated by a non-cytolytic L3T4+ idiotype-specific T cell.
Authors: Ghosh S K , Bankert R B 
Published: December 2022

Abstract
We previously reported that idiotype (Id)-loss, stable somatic variants of a B cell hybrid, 2C3E1, are generated both in vitro and in vivo, after interaction of the Id-positive tumor cells with autologous Id-specific effector T cells. The present investigation was undertaken to elucidate further the nature and functional characteristics of the effector T cells. We report here that the idiotype-specific cells mediating the generation of Id- tumor variants are Thy1+ L3T4+ Lyt-2- cells, which respond to specific idiotypic stimulation by secreting IL-2 in vitro. No IL-2 is secreted in response to unrelated Ig or an Id/Ig-2C3E1 tumor variant. Furthermore, the Id-specific T cells exert strong suppressive effects on the expression of 2C3E1 Ig and the effects can be reversed by blocking the L3T4+ T cells with monoclonal anti-L3T4 antibody in vitro during the initial 3 days of co-culture. After 4 days, the T cell-mediated suppression of the 2C3E1-Id is irreversible. In addition to the in vitro studies we have determined that the administration of anti-L3T4 mAb to mice just before priming with idiotype-bearing tumor cells also abrogates the suppressive effects of the idiotype primed spleen cells on Ig expression of 2C3E1. To study the Id-specific effector T cells in more detail we have generated functional Id-specific L3T4+ T cell lines. These T cell lines have been shown to recapitulate the generation of Id- tumor variants that we observed with Id-primed spleen cells. It is concluded that L3T4+, Id-specific Ts cells are responsible for the generation of somatic variants of the B cell hybrid 2C3E1 and that the induction or selection of these variants progresses from a reversible phase to an irreversible phase.
The requirements for triggering of lysis by cytolytic T lymphocyte clones. II. Cyclosporin A inhibits TCR-mediated exocytosis by only selectively inhibits TCR-mediated lytic activity by cloned CTL.
Authors: Lancki D W , Kaper B P , Fitch F W 
Published: December 2022

Abstract
TCR-mediated granule exocytosis, as measured by the release of serine esterase activity, has been implicated in the lytic process of Ag-specific CTL. Exocytosis appears to be the mechanism of release of other lysis-relevant molecules including cytotoxic lymphokines and proteins that have the capacity to induce membrane lesions as measured by the hemolysis of non-nucleated SRBC. In the studies presented here, we assessed the contribution of exocytosis and lymphokine production in CTL lysis of nucleated and non-nucleated target cells by using a panel of murine CTL clones. Ag-mediated activation of cytolysis, lymphokine production, and exocytosis could be mimicked by mAb against the TCR/CD3 complex, or by stimulation with the combination of PMA + calcium ionophore, which appear to bypass the TCR (neither PMA nor calcium ionophore alone induced these functions efficiently in our CD8+ CTL clones). Although lysis, IFN-gamma production and exocytosis of N-alpha-benzyloxycarbonyl-L-lysin esterase (BLTE) activity were induced by either stimulus, we were able to identify distinct activation requirements for each of these functions. We found that lymphokine production, exocytosis, and cytolysis could be selectively inhibited. Cycloheximide inhibited IFN-gamma production, but did not inhibit exocytosis of BLTE activity or cytolysis. In addition we showed that cyclosporine A (CsA) profoundly inhibited IFN-gamma production as well as exocytosis induced by stimulation through the Ag receptor or by PMA + calcium ionophore. In contrast, CsA had little or no effect on lysis of nucleated target cells that bear the relevant Ag. These findings indicate that our CTL clones can lyse target cells by a mechanism independent of exocytosis or (de novo) lymphokine production. To directly assess the capacity of our CTL clones to lyse target cells without inducing nuclear damage we developed a system of coating non-nucleated SRBC with anti-CD3 mAb for use as stimuli and as targets for lysis. We found that our cloned CTL were indeed activated to produce IFN-gamma by SRBC that were coated with anti-CD3 mAb, and, furthermore, they were able to lyse the SRBC in a short term cytolytic assay. Thus our CD8+ CTL are capable of lysing certain target cells by a mechanism independent of DNA degradation, presumably by inducing a membrane lesion. In addition, CsA did inhibit lysis of the non-nucleated SRBC targets as well as exocytosis of BLTE activity.(ABSTRACT TRUNCATED AT 400 WORDS)
Two monoclonal antibodies identify thymic-repopulating cells in mouse bone marrow.
Authors: Spangrude G J , Klein J , Heimfeld S , Aihara Y , Weissman I L 
Published: December 2022

Abstract
The progenitor cells in the bone marrow that home to and repopulate the thymus have been incompletely characterized. In particular, it is not clear whether thymocytes differentiate directly from pluripotent hemopoietic stem cells that seed to the thymus, or whether T lymphoid-committed stem cells (prothymocytes) arise in the bone marrow before the thymic migration. In order to resolve this question, we have used mAb specific for cell-surface Ag to identify the bone marrow cells which can seed to and repopulate the thymus of irradiated mice. We report here that the majority of thymic-repopulating cells in mouse bone marrow express low levels of the Thy-1 Ag (Thy-1lo) plus high levels of a newly described Ag termed stem cell Ag (Sca-1). Two distinct populations of thymic-repopulating Thy-1loSca-1+ cells in mouse bone marrow can be discriminated based on expression of any of a number of hemolymphoid lineage-specific (Lin) markers. Thus, Thy-1loLin-Sca-1+ and Thy-1loLin+Sca-1+ fractions of bone marrow contain thymic-repopulating cells. A second Ag, stem cell Ag-2 (Sca-2), is expressed by Thy-1loLin+Sca-1+ cells but not by Thy-1loLin-Sca-1+ cells. The Thy-1loLin-Sca-1+ fraction expresses intermediate levels of the phagocyte glycoprotein-1 Ag, and comprises 30% of the Thy-1loLin- bone marrow cells, which have previously been shown to be highly enriched in pluripotent hemopoietic stem cells. By facilitating the isolation of highly purified subpopulations of bone marrow cells that can repopulate the thymus, Sca-1 and Sca-2 should provide an experimental tool for describing the developmental potential of such bone marrow subsets.
A natural neonatal hybridoma autoantibody to the T200 antigen.
Authors: Glotz D , Zanetti M 
Published: December 2022

Abstract
We report on the production and characterization of a murine hybridoma generated from neonatal (less than 24 h from birth) unstimulated BALB/c splenocytes that produces an IgG2b kappa-antibody (21G10) reacting with a cell surface Ag of murine lymphocytes. By immunoprecipitation technique we determined that the Ag recognized by autoantibody 21G10 has an apparent m.w. of 200 kDa and is present on both T and B lymphocytes but not on fibroblasts. Together with the pattern of immunoprecipitation and the cell lineage distribution we suggest that autoantibody 21G10 likely recognizes the common leukocyte Ag T200. This is further inferred by using a mutant (T200-) cell line and a reference anti-T200 mAb in immunodepletion experiments. Functionally, autoantibody 21G10 blocks (greater than 90%) the incorporation of [3H]TdR by T lymphocytes stimulated in vitro with Con A, and inhibits the production of IL-2 by these cultures. This report demonstrates the existence of autoantibodies directed against lymphocyte cell surface Ag within the natural preimmune repertoire. The implication of this finding with regard to T-B cells interaction early in ontogeny is discussed.
The xid mutation affects hemopoiesis in long term cultures of murine bone marrow.
Authors: Hayashi S , Witte P L , Kincade P W 
Published: December 2022

Abstract
Cells of the humoral immune system are particularly affected by a mutation at the X chromosome linked immunodeficiency disease (xid)locus. Although B cells are made in normal numbers, they fail to become phenotypically and functionally diverse. Consequently, poor antibody responses are mounted to certain types of Ag. There have been some indications that other types of hemopoietic cells may be influenced by the mutation and development of the humoral immune system is unusually dependent on the presence of T lymphocytes. We now describe an analysis of the lympho-hemopoietic environment studied with long term bone marrow cultures. Contrary to expectations, cultures initiated with cells from homozygous female or hemizygous male mice with the mutant allele established more quickly than normal. The accelerated initial growth pattern was clearly linked to the xid mutation. Artificial mixtures of marrow exhibited intermediate growth kinetics. Experiments with H-2 congenic and T6 chromosome marked cells did not reveal an intrinsic dominance of growth in nonadherent xid cells. Similar results were obtained with culture conditions which favored production of myeloid or lymphoid cells. These findings would be consistent with subtle changes in the bone marrow microenvironment resulting from the xid mutation. The pedigree of the mouse strains had a significant influence on lymphopoiesis in long term bone marrow cultures. Lymphocytes of BALB/c origin dominated over CBA/H background cells in cultures established from mixtures of the two, but this did not correlate with any functional deficiency in CBA/H stromal cells. In fact, establishment of an adherent layer was a rate-limiting step in initiating long term cultures and this could be achieved with a low dose inoculum of CBA/H marrow. Even more dramatic effects were found in hemopoietic cells from doubly defective C3H.nu/nu-xid mice. The bone marrow of these athymic animals contained normal numbers of granulocyte/macrophage progenitors. However, lymphoid cultures could not be reproducibly established with their cells and myelopoiesis was never observed in vitro. The relatively simple conditions which pertain in culture make it possible to appreciate effects of mutations and pedigree on hemopoiesis which are unremarkable in intact animals.
Regulation of monocyte/macrophage C2 production and HLA-DR expression by IL-4 (BSF-1) and IFN-gamma.
Authors: Littman B H , Dastvan F F , Carlson P L , Sanders K M 
Published: December 2022

Abstract
IL-4 was originally described on the basis of its ability to co-stimulate the proliferation of resting B cells treated with anti-IgM. Recently, this cytokine has been shown to have other effects on mast cells, T cells, B cells, and macrophages. We studied the ability of IL-4 to regulate the production of C2 by human monocytes and monocytic cell lines and compared this with stimulation of HLA-DR expression, another recently described activity of IL-4. Responses to IL-4 were compared to IFN-gamma, a cytokine with both activities. IL-4 up-regulated C2 production by human monocytes and this effect was not inhibited by neutralizing anti-IFN-gamma antibody. IL-4 also stimulated C2 production by HL-60 cells that had been pre-treated with vitamin D3 to induce monocytic differentiation. IL-4 did not stimulate C2 production by U937 cells. IFN-gamma, in contrast to IL-4, stimulates C2 production by all three cell types. Although IL-4 increased C2 production by HL-60 cells we could not detect C2 mRNA by Northern blotting. However, co-stimulation of these cells with IL-4 and low concentrations of IFN-gamma resulted in an additive effect on C2 production and a greater increase in C2 mRNA than was seen with IFN-gamma alone. As reported by others, IL-4-stimulated HLA-DR expression by monocytes. In contrast to our findings regarding C2 production, stimulation of HLA-DR expression was inhibited by neutralizing anti-IFN-gamma mAb and IL-4 did not stimulate HLA-DR expression by U937 or HL-60 cells. IFN-gamma stimulated HLA-DR expression by all three cell types. These results identify IL-4 as an additional cytokine able to directly stimulate C2 production by human monocytes and by a monocytic cell line whereas IL-4 stimulation of HLA-DR expression by monocytes appears to be IFN-gamma dependent.