bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural definition of a family of Ld-like molecules distributed among four of seven haplotypes compared.
Authors: Lillehoj E P , Myers N B , Lee D R , Hansen T H , Coligan J E 
Published: December 2022

Abstract
Comparative tryptic peptide analyses were performed on 12 different D region molecules representing seven different haplotypes. The Dd, Dq, and Dw16 regions were shown to encode multiple, antigenically distinct molecules (Dd Ld, Dq Lq Rq, and Dw16 Lw16, respectively). In addition, each of these molecules was found to have a unique primary structure, implying that they are the products of separate genes. However the previously described Rd molecule, which was identified by sequential immuno-precipitation and 2-D gel analyses, was indistinguishable from Ld by tryptic peptide mapping, implying that these two molecules may be products of the same gene. The Db, Ddx, Dk, and Dp regions were found to determine a single molecule with the reagents tested. Intra- and/or inter-haplotype comparisons of the peptide maps of each of these D region molecules revealed widely disparate structural relationships. For example, the Db, Dq, Lq, Rq, Dw16, and Lw16 molecules all showed striking homology with the Ld molecule. Members of this family share between 43 to 55% peptide homology with Ld, indicating a high conservation of primary structure (greater than 90%). However, because Dq and Dw16 region-encoded molecules show no exceptional relationship to each other, the portion of the conserved sequence is not the same for each of these Ld-like molecules. By contrast, comparisons of the Dk, Dd, Ddx, and Dp molecules with Ld or with each other revealed tryptic peptide homologies ranging from 22 to 38%, suggesting a sequence homology of 70 to 85%. When compared with the Kb molecule, each of the D region molecules showed between 21 to 36% peptide map homology (70 to 85% sequence homology). These studies indicate, therefore, that there is a family of Ld-like molecules representing several distinct haplotypes. This definition of a highly homologous family of D region molecules suggests that many D-region molecules have evolved from an Ld-like primordial gene and that in different haplotypes different portions of this prototypic structure have been maintained.
Two distinct class II molecules encoded by the genes within HLA-DR subregion of HLA-Dw2 and Dw12 can act as stimulating and restriction molecules.
Authors: Sone T , Tsukamoto K , Hirayama K , Nishimura Y , Takenouchi T , Aizawa M , Sasazuki T 
Published: December 2022

Abstract
By using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), we investigated the difference in the HLA class II molecule between HLA-Dw2 and Dw12, both of which are typed as HLA-DR2 serologically. The anti-HLA-DR framework monoclonal antibody (MoAb) HU-4 precipitated an alpha-chain and two beta-chains of human class II molecules from both Dw2 and Dw12 homozygous B lymphoblastoid cell lines. It was demonstrated clearly that an alpha-chain (alpha 1) and one of the beta-chains (beta 1) showed no difference in mobility in the 2D-PAGE between Dw2 and Dw12, but that another beta chain (beta 2) of Dw2 was distinct from that of Dw12 in the 2D-PAGE profile. Thus, MoAb HU-4 precipitated alpha 1 beta 1 and alpha 1 beta 2 molecules from Dw2 and Dw12, and the alpha 1 beta 1 molecule appears to be an HLA-DR2 molecule. The alpha 1 beta 2 molecule, on the other hand, is a class II molecule distinct from those precipitated with anti-DR2, anti-DQw1 (DC1, MB1, MT1), or anti-FA MoAbs. MoAb HU-4 completely inhibited the mixed lymphocyte culture reaction (MLR) between Dw2 and Dw12, but anti-DR2 MoAb HU-30, which reacts only with the alpha 1 beta 1 molecule, did not show an inhibitory effect on the MLR between Dw2 and Dw12. The alpha 1 beta 2 molecule is therefore the molecule which elicits MLR between Dw2 and Dw12. An IL 2-dependent T cell line established from an HLA-Dw12/D blank heterozygous high responder to the streptococcal cell wall antigen (SCW) clearly distinguished the Dw2 specificity from Dw12 specificity expressed on the antigen-presenting cell (APC). Moreover, MoAb HU-4 markedly inhibited the cooperation between the T cell line and APC to respond to SCW. These observations indicate that the alpha 1 beta 2 molecule is recognized as a restriction molecule by the T cell line at the antigen presentation of SCW through APC MoAb HU-30 on the other hand partially inhibited the MLR between Dw2 or Dw12 homozygous cell as a stimulator cell and non DR2 cell as a responder cell. It markedly inhibited the proliferative response of the Dw12/D- heterozygous T cell line to SCW, presented by Dw2+ but Dw12- allogeneic APC, and the peripheral response of Dw2 or Dw12 homozygous peripheral blood lymphocytes to SCW. Thus, two distinct class II molecules encoded by the genes within the HLA-DR subregion of HLA-Dw2 and Dw12 can act as stimulating molecules in the MLR and as restriction molecules in the antigen presentation by APC.
Activation of mouse peritoneal macrophages alters the structure and surface expression of protein-bound lactosaminoglycans.
Authors: Mercurio A M , Robbins P W 
Published: December 2022

Abstract
We have begun to analyze and compare the surface carbohydrates present on populations of resident and activated mouse peritoneal macrophages. The activated macrophage populations studied include TG-elicited macrophages, BCG-activated macrophages, and resident macrophages cultured for 24 hr in the presence of lymphokines or heterologous serum. Analysis of glycopeptides generated by pronase digestion of surface glycoproteins labeled by the neuraminidase/galactose oxidase/NaB3H4 method indicates that the macrophage surface contains a class of high m.w. carbohydrates susceptible to degradation by endo-beta-galactosidase, lactosaminoglycans. These lactosaminoglycans are sialylated type 2 carbohydrates containing the repeating lactosamine disaccharide Gal beta 1-4GlcNAc as well as fucose residues. Macrophage activation was observed to markedly alter surface lactosaminoglycans. The alterations observed include 1) an increase in surface expression as determined by both an increase in neuraminidase/galactose oxidase/NaB3H4 labeling and by the ability of activated but not resident macrophages to bind I antibodies as assayed by indirect immunofluorescent surface staining, 2) the addition of alpha-galactose residues, and 3) an increase in GlcNAc beta 1-6Gal branching as indicated by an increased resistance to endo-beta-galactosidase degradation and by the ability of activated macrophages to bind I antibodies. These observations demonstrate that macrophage activation results in specific and substantial alterations in protein-bound surface carbohydrates.
Synthesis of C1 inhibitor (C1-INA) by a human monocyte-like cell line, U937.
Authors: Randazzo B P , Dattwyler R J , Kaplan A P , Ghebrehiwet B 
Published: December 2022

Abstract
Human monocytes are known to synthesize many of the components of complement, including C1-INA. In this report we demonstrate that the human monocyte-like cell line U937 is also capable of synthesizing functional C1-INA. This was shown in several ways, including 1) incorporation of tritiated amino acids into antigenic C1-INA, immunoprecipitation, and detection by fluorography; 2) a sensitive ELISA, which allowed quantitation of antigenic C1-INA in cell lysates, and 3) a C2-dependent hemolytic assay in which the functional activity of U937 C1-INA was assayed. Data from the ELISA indicate that U937 cells contain between 2.1 to 12.8 ng of C1-INA per 1 X 10(6) cells. Furthermore, fluorescence-activated cell sorter analysis revealed that approximately 16% of U937 cells carry C1-INA as a surface bound antigen. Other proteins found to be synthesized by U937 cells include C1r, C8, and possibly alpha-2-macroglobulin. These results suggest that the U937 cell line could be a convenient and valuable model for the study of monocyte C1-INA synthesis and physiology.
Differential effects of leukotriene B4 on T4+ and T8+ lymphocyte phenotype and immunoregulatory functions.
Authors: Rola-Pleszczynski M 
Published: December 2022

Abstract
Leukotriene B4 (LTB4) can regulate several lymphocyte functions, including the augmentation of cytotoxic activity and the induction of suppressor cells. When T lymphocytes were preincubated with picomolar concentrations of LTB4, they would suppress the proliferative response of unfractionated peripheral blood mononuclear leukocytes to concanavalin A in a subsequent co-culture system. Such a suppression did not occur when the responding population was depleted of monocytes. Furthermore, the effect was reversed to an enhancement when the responding unfractionated population was treated with indomethacin, suggesting a role for monocytes and cyclooxygenase products in the effector phase of LTB4-induced suppressor activity. When sorted into T4+ and T8+ cells before preincubation with LTB4, both T cell subsets could be induced by LTB4 to exert suppression. T4+ cells, however, required the presence of monocytes in the responder population in order to manifest suppressor activity, whereas T8+ cells were active even in the absence of monocytes. When LTB4-preincubated T cells or T4+ cells were sorted into T4+ and T8+ subsets after preincubation, suppressor cell activity was found only in the T8+ subset. Furthermore, T8+ cell-depleted T lymphocyte cultures, incubated for 24 hr with LTB4, showed a significant increase in the proportion of T8+ cells. Together, these data suggest that LTB4 induces suppressor T cells which can derive from either T4+ or T8+ subpopulations but which are phenotypically T8+ when exerting their suppressive activity. Thus, by interacting with both T4+ and T8+ lymphocytes, LTB4 can modulate immune responses with the cooperation of functionally competent accessory monocytes.
Characterization of developmentally regulated epitopes of Schistosoma mansoni egg glycoprotein antigens.
Authors: Weiss J B , Strand M 
Published: December 2022

Abstract
The chemical and antigenic composition of a major group of concanavalin A-binding glycoprotein antigens of Schistosoma mansoni eggs was examined by the use of monoclonal antibodies. The individual glycoproteins of this group each displayed a very wide range of apparent m.w. and had isoelectric points of less than 5 when analyzed by two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. These glycoproteins could be chemically labeled with 125Iodine by two different methods and biosynthetically labeled with 35S-methionine during in vitro synthesis by isolated eggs. By using five monoclonal antibodies, the individual egg glycoproteins were shown to share several antigenic determinants when analyzed by radioimmunoprecipitation and solid-phase binding assays. These epitopes were present in a high level, and the degree of expression appeared to be developmentally regulated. In addition, Schistosoma haematobium and Schistosoma japonicum eggs contained antigenically related glycoprotein antigens. Preliminary evidence suggests that the epitopes involve carbohydrate moieties.
Expression of a laminin-like substance on the surface of murine natural killer (NK) lymphocytes and its role in NK recognition of tumor target cells.
Authors: Hiserodt J C , Laybourn K A , Varani J 
Published: December 2022

Abstract
We have identified a structure on the surface of murine NK cells that is immunochemically cross-reactive with laminin. Treatment of normal CBA/J spleen cells with monospecific anti-laminin serum plus complement completely eliminated NK cytolytic activity against YAC-1 or RL male 1 target cells. In the absence of added complement, spleen cells preincubated with anti-laminin serum were also reduced in their cytolytic activity due to a reduced capacity to bind to the target cells. Treatment with anti-asialo GM1 serum plus complement also eliminated NK activity, but pretreatment of NK cells with anti-asialo GM1 in the absence of complement did not reduce cytolytic activity. Thus, anti-laminin and anti-asialo GM1 bind to structures on the surface of NK cells that distinguish functional (laminin) from nonfunctional (asialo GM1) sites. Flow cytometric analysis revealed that approximately 15% of normal nonadherent splenic lymphocytes expressed laminin-like structures, whereas 16% expressed asialo GM1 and 19% expressed the NK alloantigen NK 2.1. Treatment of alloimmune cytotoxic T lymphocytes (CTL) with anti-laminin plus complement did not affect CTL activity. Thus, anti-laminin serum appears to detect a cell surface structure present on the NK subset of lymphocytes.
Monoclonal antibodies against human myelomonocytic cells: detection of certain lineage-specific antigens on CFU-GM progenitor cells.
Authors: Takaishi M , Fu S M 
Published: December 2022

Abstract
A series of monoclonal antibodies (mAb) were raised against nonlymphoid leukemic cell lines. Three of them have been characterized in detail. mAb H8 (IgG2), mAB U2 (IgG1), and mAb ML143 (IgM) were established with HEL, an erythroleukemia cell line, U937, a monocytoid (histiocytic) line, and ML-1, a myeloid cell line as immunogen, respectively. A 65 to 75 KD polypeptide was precipitated from monocytes by mAb H8, a 160 KD protein from monocytes by mAb U2, and two broad bands in the regions of 150 and 195 KD from granulocytes by mAb ML143. All three mAb stained peripheral blood monocytes and granulocytes, but not lymphocytes, platelets, and erythrocytes. The mAb reacted with immature myeloid cells in bone marrow, ranging from myeloblasts to mature myelomonocytic cells. They also were reactive with various nonlymphoid cell lines and leukemia of myelomonocytic origin. They did not react with B cell lines and B cell CLL cells. By complement-mediated cytolysis and/or an immune rosette method, antigens H8 and U2 were found to be expressed on the vast majority of CFU-GM (14 days) progenitors but not on BFU-E. Antigen ML143 was not expressed by either progenitor. Furthermore, ML143 antigen was found on T leukemia cell lines, a subpopulation of mitogen-activated T cells, and certain non-T/non-B ALL cells. This reactivity was not found with mAb H8 and U2. The relationship between these mAb and those reported are discussed. The possibility of using these mAb to obtain a markedly enriched CFU-GM progenitor population is also raised.
Undiminished immunologic tolerance to contact sensitivity in mast cell-deficient W/Wv and Sl/Sld mice.
Authors: Mekori Y A , Galli S J 
Published: December 2022

Abstract
Several mast cell-derived mediators, when tested individually, have actions that may be considered immunosuppressive or anti-inflammatory. Yet evidence concerning the importance of mast cells to the down regulation of T cell-dependent immune responses in vivo is scanty and contradictory. To test directly the net contribution of intact mast cells to the suppression of delayed hypersensitivity reactions in vivo, we attempted to elicit tolerance to contact sensitivity in W/Wv or Sl/Sld mast cell-deficient mice, and compared their responses with those of littermate control mice with normal numbers of mast cells. By using three different measures of delayed hypersensitivity (ear swelling, weight ratios of challenged and control ears, and 125I-IUDR-labeled leukocyte infiltration into challenged and control ears), we detected no deficiency in the 24 hr contact sensitivity reactions to DNFB in control (nontolerized) W/Wv or Sl/Sld mice. We thus confirmed previous work indicating that mast cells are not essential for the induction and elicitation of delayed hypersensitivity. Furthermore, mast cell-deficient and control mice developed equivalent levels of tolerance to contact sensitivity. This was true for tolerance induced by DNBS administered i.v. 7 days before epicutaneous sensitization with DNFB, and for tolerance induced by supraoptimal sensitization with DNFB. W/Wv and Sl/Sld mice also served as suitable donors and recipients for putative suppressor T cells (Ts) induced by i.v. DNBS. We conclude that mast cells make little or no contribution to the modulation of Ts activity in two different models of Ts-dependent tolerance to contact sensitivity.
Clonal analysis of cytolytic T lymphocyte-mediated lysis of target cells with inducible antigen expression: correlation between antigen density and requirement for Lyt-2/3 function.
Authors: Shimonkevitz R , Luescher B , Cerottini J C , MacDonald H R 
Published: December 2022

Abstract
The lysis by allospecific cytolytic T lymphocytes (CTL) of the BALB/c lymphoma ST-4.5, a cell line that can be induced by interferon-gamma (IFN-gamma) to express increased amounts of major histocompatibility complex (MHC) class I antigens, was investigated. Culture of ST-4.5 in IFN-gamma increased the surface expression of Kd molecules from originally low levels and Dd from undetectable amounts by approximately fivefold as determined by fluorescence-activated cell sorter (FACS) analysis, whereas the levels of several other antigens (Ld, I-Ad, Thy-1, Lyt-2, L3T4, and LFA-1) were not affected. The lysis of ST-4.5 by Dd- and Ld-specific CTL clones correlated with the expression of those antigens on target cells as determined by both FACS and biochemical analysis. Lysis of ST-4.5 by CTL clones specific for Kd antigen fell into two distinct groups: those that could lyse targets cultured either normally or in IFN-gamma, and those that could only lyse targets that had been precultured in IFN-gamma. The apparent sensitivity to antigen exhibited by the Kd-specific CTL clones predicted their sensitivity to inhibition of target lysis by anti-Lyt-2/3 antibody. Those CTL clones that were only active against ST-4.5 expressing higher amounts of surface antigen (resulting from IFN-gamma preculture) were readily inhibited by anti-Lyt-2/3 antibody, whereas those CTL capable of lysing normally cultured targets having lower amounts of surface antigen were heterogeneous in their sensitivity to anti-Lyt-2/3; some were inhibitable, whereas others were resistant. In addition, another CTL clone that was resistant to inhibition by anti-Lyt-2/3 alone was readily inhibited by a synergistic combination of anti-Lyt-2/3 plus anti-Kd (but not anti-Dd or Ld) antibodies. These results indicate that CTL antigen receptor sensitivity to (or affinity for) antigen and the level of specific antigen expression by the target cell may both be important criteria in assessing Lyt-2/3 molecule function in CTL-mediated cytolysis. The function of recognition-associated molecules such as Lyt-2/3 may be to strengthen and increase the number of receptor-ligand binding events that facilitate CTL-target membrane interactions that lead to the lysis of the target cell.
The interaction of nominal antigen with T cell antigen receptors. I. Specific binding of multivalent nominal antigen to cytolytic T cell clones.
Authors: Siliciano R F , Keegan A D , Dintzis R Z , Dintzis H M , Shin H S 
Published: December 2022

Abstract
In this report, we describe an experimental strategy for analyzing the interaction of nominal antigen with antigen-specific T cell clones. Our approach was based on the notion that low affinity interactions between nominal antigen and T cell antigen receptors might be detected by using a highly multivalent form of the antigen in which a large number of identical, appropriately spaced epitopes are attached to a polymer backbone. Antigens of this kind should be capable of multivalent binding to receptors on the T cell, resulting in a marked enhancement of the overall avidity of the interaction. To examine this possibility, we established a series of murine cytolytic T cell (Tc) clones specific for the readily detectable hapten fluorescein isothiocyanate (FL). These clones lysed FL-conjugated target cells in an antigen-specific fashion and also showed specificity for target cell MHC gene products. The interaction of these clones with the nominal antigen FL was assessed by flow cytometry, using a series of water-soluble FL-conjugated polymers varying in polymer backbone and FL isomer. High m.w. (600 to 2000 Kd) polymers of acrylamide, dextran, or Ficoll conjugated with 300 to 800 FL groups/molecule bound specifically to anti-FL Tc clones. There was little binding to syngeneic spleen cells, thymocytes, noncytolytic T cell clones, or T cell clones specific for other haptens such as NIP. Polymer concentrations in the 1 to 10 micrograms/ml range produced readily detectable binding within minutes at 20 degrees C, and the binding approached plateau levels at polymer concentrations of between 100 and 300 micrograms/ml. Studies with closely related FL isomers showed that the same antigen fine specificity was operative in both lysis of FL-conjugated target cells and in binding of FL-conjugated polymers. The functional significance of the observed binding was assessed by measuring the effect of FL-conjugated polymers on lymphokine secretion by the clones. High m.w. FL-conjugated polymers caused a dose-dependent increase in the production of macrophage activation factor (MAF) by anti-FL Tc clones, but did not increase MAF production by an NIP-specific clone. In contrast, concanavalin A induced MAF production by both FL-specific and NIP-specific clones. Thus, the observed binding is both specific and functionally significant. These results suggest that soluble nominal antigen, in an appropriately multivalent form, can bind specifically to antigen receptors on Tc clones.
Mechanism controlling the genetic restrictions of an NP-specific suppressor factor that inhibits B cell responses.
Authors: Hausman P B , Sherr D H , Dorf M E 
Published: December 2022

Abstract
The mechanism of B cell suppression by a T cell hybridoma-derived monoclonal effector suppressor factor (TsF3) was studied in the 4-hydroxy-3-nitrophenyl acetyl (NP) system. The NP-specific effector suppressor cells that produce TsF3 are Lyt-1-, 2+, I-J+, NP-binding T cells and are induced by immunization with NP conjugates. Monoclonal TsF3 inhibits both T cell activity as measured by suppression of contact sensitivity responses and B cell function as measured by suppression of antibody production to both T-independent and T-dependent antigens. The present studies were designed to specifically investigate the mechanisms and genetic restrictions that govern the interactions between TsF3 and its target cells in the plaque-forming cell (PFC) response. The results show that the target of TsF3 is a splenic adherent cell. Suppression will occur only if the restriction specificity of the TsF3 matches the H-2 genotype of the adherent population. Once this TsF3-adherent cell interaction has occurred, suppression of NP-specific B cells can occur across an H-2 barrier. The data also demonstrate that Igh-linked gene products do not appear to play a part in the TsF3-mediated suppression of in vitro PFC responses, which contrasts with the requirements for regulation of T cell-mediated contact sensitivity responses.