bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multiple loci mediate B cell repertoire ontogeny: analysis of the hemagglutinin-specific repertoires in neonatal C.B20 and (C.B20 x B10.D2)F1 mice.
Authors: Cancro M P 
Published: December 2022

Abstract
The HA-specific B cell repertoires of 12 to 14-day-old C.B20 and (C.B20 X B10.D2)F1 mice have been characterized and compared to those of BALB/c, B10.D2, and (BALB/c X B10.D2)F1 mice to assess the role of allotype-linked loci in the process of repertoire formation. Both C.B20 and (C.B20 X B10.D2)F1 neonates express repertoires similar to (BALB/c X B10.D2)F1s of the same age, and allotypic analysis indicates that nonparental clonotypes observed in (BALB/c X B10.D2)F1s at this developmental stage are derived predominantly from the B10.D2 parent. In conjunction, these findings indicate that: a) allotype-linked loci, although influential in repertoire formation, clearly interact with loci elsewhere in the genome to shape the expressed repertoire phenotype; b) developmental preference may exist among heterozygous individuals regarding the time at which particular elements of each parental VH haplotype are expressed; and c) the factors that control this preference are dictated by heritable elements unlinked to Ig allotype loci.
Determinants of the localization, magnitude, and duration of a specific mucosal IgA plasma cell response in enterically immunized rats.
Authors: Pierce N F , Cray W C 
Published: December 2022

Abstract
The origin and fate of specific IgA plasma cells in intestinal lamina propria were studied in rats immunized enterically with cholera toxin (CT). Our major goal was to define how an anti-CT response is focused and sustained at the site of antigen challenge. To distinguish antigen-dependent from antigen-independent mechanisms, CT exposure was restricted to defined portions of intestine and, in some studies, the distribution of antitoxin-containing plasma cells (ACC) was examined in nonimmune adoptive recipients of post-challenge thoracic duct lymphocytes. After enteric priming and challenge, ACC appeared throughout the gut, but were most numerous at the challenged site. About 25% of ACC appearing at the site of jejunal challenge were due to antigen-driven proliferation of memory cells within the lamina propria; the remainder arose elsewhere, apparently in mucosal follicles or mesenteric lymph nodes, and migrated systemically as antitoxin-containing plasmablasts before homing to the lamina propria. The homing of these migrating ACC precursors was not affected by mucosal exposure to CT, nor did they undergo appreciable antigen-driven division after arrival in gut lamina propria. However, homing was specific for the organ from which they arose, i.e., precursors arising from duodenal challenge homed selectively to jejunum, whereas those from colonic challenge homed to the colon. The organ specificity of homing was determined during the challenge response and was independent of the origin of memory cells participating in the response. The survival of migrating ACC precursors did not differ in segments of gut exposed or nonexposed to CT. However, CT exposure at the time of their migration evoked another secondary-type response, due to stimulation of comigrating memory cells, thus sustaining the secondary response at a high level. These results and those in a previous report identify important mechanisms that affect the localization, magnitude, and duration of a specific IgA response, at least in the intestine. These include: 1) organ-specific homing of migrating IgA plasmablasts, 2) antigen-driven generation of IgA plasma cells from memory cells within the lamina propria, 3) enhanced memory at the site of mucosal priming compared to that a distant mucosae, and 4) regeneration of memory cells during the secondary response.
Phorbol ester-induced differentiation of a non-T, non-B leukemic cell line: model for human lymphoid progenitor cell development.
Authors: LeBien T W , Bollum F J , Yasmineh W G , Kersey J H 
Published: December 2022

Abstract
The phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) was tested for its ability to induce phenotypic changes in the human non-T,. non-B ALL cell line REH. Cells were cultured with nanogram concentrations of TPA for up to 48 hr, and were analyzed by indirect immunofluorescence with a panel of monoclonal antibodies and an antibody to the enzyme terminal deoxynucleotidyl transferase (TdT). TPA induced REH cells to express the leukemia-associated antigen, p24 (detected with monoclonal antibody BA-2; p24/BA-2) by 8 hr of culture, with induction complete by 24 hr. TPA-treated cells also underwent a concomitant decrease in the expression of TdT when analyzed enzymatically or by immunofluorescence. Analysis of TPA-treated cells with monoclonal antibodies BA-1 (detecting a B cell-associated antigen), 7.2 (detecting a monomorphic HLA-DR antigen), or OKT11 (detecting a structure closely associated with the E receptor) showed no change compared to controls. In addition there was no detectable cytoplasmic immunoglobulin in control or TPA-treated cells. These results show clearly that TPA is capable of inducing phenotypic changes in REH cells. Such changes may reflect the differentiation-linked expression of antigens present in normal bone marrow lymphoid progenitor cells.
Antibody-induced release of cellular proteinases: loss of adhesion of human melanoma cells after binding of anti-melanoma antibody.
Authors: Singer K H , Hashimoto K , Stuhlmiller G M , Lazarus G S 
Published: December 2022

Abstract
Incubation of monolayer cultures of human melanoma cells with monkey anti-human melanoma IgG resulted in loss of cellular adhesion. Release of melanoma cells from the culture dish was not the result of cytotoxicity. Antibody-induced cell detachment was partially inhibited by the addition of diisopropylfluorophosphate (DFP), and detachment was completely inhibited by the addition of lima bean trypsin inhibitor. Thiol and carboxyl proteinase inhibitors did not block antibody-induced cellular detachment. An IgG dose-dependent increase in DFP-inhibitable caseinolytic activity was demonstrated in the culture medium of melanoma cells incubated with anti-melanoma IgG, but not in those incubated with normal monkey IgG. Medium collected from antibody-treated cell cultures and incubated with protein A-Sepharose to remove IgG caused detachment of melanoma cells in fresh cultures. Preincubation of this conditioned medium from antibody-treated cell cultures with DFP abolished the medium's ability to mediate loss of cellular adhesion. These data suggest that incubation of melanoma cells with immune IgG results in release of a serine proteinase that mediates cellular detachment.
Dna isolated from DNA/anti-DNA antibody immune complexes in systemic lupus erythematosus is rich in guanine-cytosine content.
Authors: Sano H , Morimoto C 
Published: December 2022

Abstract
DNA fragments were isolated from DNA/anti-DNA antibody immune complexes of systemic lupus erythematosus. Hybridization experiments indicated that DNA isolated from immune complexes originates from human nuclear DNA. Two classes of DNA were identified by polyacrylamide gel electrophoresis. The m.w. of small fragments was 25,000 with 30 to 40 base pairs, and that of large fragments was 100,000 with 150 base pairs. The average guanine-cytosine (G-C) content in the small fragments was 55% of total bases, and that in the large fragments was 45%. Compared with the average 38% G-C content of total human DNA, the antigen DNA is rich in G-C content. Such unusually high G-C content can alter DNA structure, which may serve as the target for antibody production.
The immune response to an isomaltohexosyl-protein conjugate, a thymus-dependent analogue of alpha(1 replaced by 6) dextran.
Authors: Stein K E , Zopf D A , Johnson B M , Miller C B , Paul W E 
Published: December 2022

Abstract
Two oligosaccharides derived from B512 dextran (Dex), isomaltohexaose (IM6), and isomaltotriose (IM3) have been coupled to keyhole limpet hemocyanin (KLH) and the conjugates studied as thymus-dependent (TD) immunogens analogous in their specificity to Dex. Both IM3-KLH and IM6-KLH stimulate an anti-Dex response in CBA mice. In C57BL mice, only IM6-KLH stimulated an anti-Dex response; IM3-KLH, although immunogenic, failed to elicit the production of anti-Dex antibodies. Similarly, CBA anti-Dex antibodies cross-reacted with both IM3 and IM6 coupled to bovine serum albumin (BSA), whereas C57BL anti-Dex antibodies cross-reacted with IM6-BSA and bound IM3-BSA only very poorly. This reciprocal lack of cross-reactivity between IM3 conjugates and Dex in C57BL mice was controlled by genes linked to the IgH locus, as shown in responses of allotype congenic CBA mice. This genetically regulated fine specificity pattern was overridden when IM6-KLH was used for immunization. C57BL antibodies that bound both Dex and IM3-BSA were produced in response to this antigen. Thus, isomaltohexosyl-protein conjugates provide Dex-like antigens that differ from Dex itself in terms of thymus dependency and the fine specificity of the precursors that are activated. They should provide important tools to study the activation requirements of antigen-specific B cells.
MLC-specific suppressor T lymphocytes in man. I. Their induction in vitro by soluble HLA-DR antigens.
Authors: Smeraldi R S , Fabio G , Bonara P , Villa M G , Vanoli M , Pettenati C , Rugarli C , Zanussi C 
Published: December 2022

Abstract
Human T lymphocytes precultured for 36 hr in the presence of soluble HLA-DR antigens suppress the MLR response of autologous peripheral blood lymphocytes to allogeneic stimulating cells. The suppression is DR antigen-specific in that it appears that the MLR stimulating cell donor and the soluble suppressor-inducing antigen must share DR specificities. The soluble DR antigens were fractionated from the sera of normal donors using QAE-Sephadex chromatography and CNBr-activated Sepharose immunoadsorption. Similarly prepared HLA-A and -B antigens failed to induce suppressive activity. The suppressive activity of DR-antigen cultured T cells is resistant to mitomycin C treatment and, further, the antigen specificity is maintained with or without mitomycin C treatment. The kinetics of suppressor cell induction as well as the kinetics of suppression in the test MLR cultures are presented. The implications of these results are discussed.
A single monoclonal anti-Ia antibody inhibits antigen-specific T cell proliferation controlled by distinct Ir genes mapping in different H-2 I subregions.
Authors: Germain R N , Bhattacharya A , Dorf M E , Springer T A 
Published: December 2022

Abstract
A xenogeneic rat anti-mouse Ia monoclonal antibody, M5/114 (gamma 2b, kappa), was studied for its effects in vitro on T cell proliferative responses. Strain distribution studies revealed that M5/114 could inhibit I-A subregion-restricted T cell responses of the H-2b,d,q,u but not the H-2f,k,s haplotypes, indicating that this xenoantibody recognizes a polymorphic determinant on mouse Ia molecules. This same monoclonal antibody was found to inhibit BALB/c (H-2d) T cell proliferation to both G60A30T10 and G58L38 phi 4. The Ir genes regulating responses to these antigens map to either the I-A subregion (GAT), or the I-A and I-E subregions (GL phi), raising the possibility that M5/114 recognizes both I-A and I-E subregion-encoded Ia glycoproteins. It could be shown, using appropriate F1 responding cells, that M5/114 does in fact affect GAT and GL phi responses by interaction with both the I-A and the I-E subregion products, and not by any nonspecific effect resulting from binding to the I-A subregion product alone. These results are consistent with genetic and biochemical studies directly demonstrating that M5/114 recognizes A alpha A beta and E alpha E beta molecular complexes. The existence of a shared epitope on I-A and I-E subregion products suggests the possibility that these molecules arose by gene duplication. Finally, the precise correlation between the Ia molecules recognized by M5/114 and the ability of this antibody to block T cell responses under Ir gene control strengthens the hypothesis that Ia antigens are Ir gene products.
Antigen-specific human T lymphocyte clones: viral antigen specificity of influenza virus-immune clones.
Authors: Lamb J R , Eckels D D , Phelan M , Lake P , Woody J N 
Published: December 2022

Abstract
Human T lymphocyte clones (TLC) specific for type A (A/Texas/1/77) influenza virus and maintained in continuous culture with T cell growth factor, were analyzed to define the cellular specificity pattern of virus recognition. A panel of TLC were stimulated with strains of serologically characterized type A influenza subtypes. Five TLC recognized all the viral subtypes; the remaining clones recognized only subtypes that shared serologically defined determinants with the immunizing subtype. In addition, the 11 TLC were analyzed for their fine antigenic specificity by using the purified viral components hemagglutinin (HA), neuraminidase (NA), matrix protein (MP), and nucleoprotein (NP). Five TLC proliferated in response to NA, four to MP, one to HA, and one to NP. None of the clones responded to the unrelated B strain influenza virus, B/Singapore. Furthermore, the fine specificity of an MP-reactive TLC was confirmed by subcloning.
The fourth component of human complement treated with amines or chaotropes or frozen-thawed (C4b-like C4): interaction with C4 binding protein and cleavage by C3b/C4b inactivator.
Authors: von Zabern I , Bloom E L , Chu V , Gigli I 
Published: December 2022

Abstract
We have shown previously that C4 treated with amines or chaotropes, although uncleaved, exhibits properties that are similar to C4b. Studies by other groups suggest that this C4b-like form of C4 is characterized by the lack of an internal thiolester bond that is present in native C4. We report here that C4 treated with N2H4 or KSCN or frozen-thawed, unlike native C4, forms a complex with C4-binding protein (C4-bp) and is cleaved by C3b/C4b inactivator (I). Fragmentation of C4b-like C4 by I occurs without previous cleavage to C4b and requires the presence of C4-bp. Cleavage of C4b-like C4 proceeds in two steps: a small fragment (16,000 m.w.) is released first, followed by cleavage of the remaining alpha-chain fragment (83,000 m.w.) into polypeptides of 46,000 (C4d) and 32,000 m.w. All fragments, except the 46,000 m.w. fragment, are disulfide-linked to the beta- and/or gamma-chains of C4. Cleavage of C4b-like C4 probably occurs at the same points in the alp a-chain as in C4b; however, C4b-like c4 also contains C4a. Based on the m.w. determinations, the C4a portion of the alpha-chain is present in the 83,000 m.w. fragment, and after the second cleavage, in the 32,000 m.w. fragment of C4b-like C4. These findings suggest the following alignment of alpha-chain fragments: the N-terminal C4a portion is attached to a polypeptide of about 25,000 m.w. (alpha 3), which is followed in the sequence by C4d (alpha 2) (46,000 m.w.) and a small 16,000 m.w. fragment (alpha 4) that forms the C-terminus.
Inhibition of secondary in vitro antibody responses by the third component of complement.
Authors: Hobbs M V , Feldbush T L , Needleman B W , Weiler J M 
Published: December 2022

Abstract
Purified human C3 was found to inhibit rat in vitro secondary antibody responses. Fifty percent inhibition of antibody-forming cell development occurred with C3 concentrations of 26 micrograms/ml. This decrease was not the result of a general toxicity or a shift in the antibody response kinetics. Using cell mixing experiments, we could not detect a C3-induced suppressor lymphocyte or macrophage. C3 was active when added to culture early (day 0 or 1 or during a 24-hr antigen prepulse) or late (day 3, 5, or 7)--the early addition being more suppressive. Regardless of the addition time, there was a characteristic 48- to 72-hr lag before the inhibitory effect was manifested. C3 could inhibit antibody-forming cell development after stimulation with the thymus-independent antigens, trinitrophenyl-Brucella abortus and dinitrophenyl-Ficoll, as well as the thymus-dependent antigens, dinitrophenyl-bovine gamma-globulin and chicken gamma-globulin suggesting that C3 was not selective for B memory cell subpopulations. Further characterization of our C3 preparation indicated that the majority of the suppressive activity resided in a small m.w. protein resembling the C3a fragment of C3. Human C3a preparations generated either by trypsin cleavage or zymosan activation of C3 were also tested in our antibody response system and were able to inhibit antibody-forming cell development. These data implicate C3 cleavage products as negative regulators of antibody formation.
Studies on the ability of monoclonal antibodies to selectively mediate complement-dependent cytotoxicity of human myelogenous leukemia blast cells.
Authors: Ball E D , Kadushin J M , Schacter B , Fanger M W 
Published: December 2022

Abstract
A panel of monoclonal antibodies that bind to leukemic blast cells from patients with acute myelocytic leukemia and chronic myelocytic leukemia in blast crisis was studied for their ability to mediate complement-dependent lysis of a variety of cell populations from patients with leukemia, normal blood cells, and human leukemia cell lines. Several of these monoclonal antibodies were selectively cytotoxic to myeloid leukemia cells (AML-1-99, AML-1-211, AML-2-30, CML-75, CML-115, and CML-150). Although they were all capable of binding to normal cell populations, none of these hybridomas were cytotoxic to normal cells. Three of these antibodies (AML-1-211. CML-75, and CML-150) were cytotoxic to some leukemia cell samples only after dilution of the hybridoma supernatant, i.e., they showed a prozone. Binding of these three antibodies, as well as another, AML-1-201, as determined in a radioimmunoassay, also showed a prozone. Other monoclonal antibodies are described (AML-2-23 and AML-2-9) that mediate complement-dependent cytotoxicity to myeloid leukemia cells as well as selected normal cell types (monocytes and lymphocytes, respectively). The potential clinical utility of these monoclonal antibodies is considered in the context of recently encountered problems in the use of monoclonal antibodies to mediate leukemia cell lysis in vivo.
Antigen presentation to T cell hybridomas by a macrophage cell line: an inducible function.
Authors: Birmingham J R , Chesnut R W , Kappler J W , Marrack P , Kubo R , Grey H M 
Published: December 2022

Abstract
We have investigated the ability of an Ia-, nonantigen-presenting macrophage tumor cell line, P388D, (H-2d), to present antigen to T cell hybridomas after incubation in a lymphokine-containing preparation. P388D, cells were incubated in microtiter wells with various concentrations of Con A-stimulated spleen cell supernatants. Antigen-specific stimulation of H-2d-restricted, KLH-specific T cell hybridomas was observed by P388D1 incubated with SUP.P388D1 cells incubated for 3 days in medium or control SUP did not present antigen. In addition, no stimulation of T hybridomas was seen by P388D1 in the inhibited by the appropriate monoclonal anti-Ia reagents. These results demonstrate that a macrophage tumor cell line can be induced to present antigen and provides for large numbers of readily available, homogeneous macrophages for studying the cellular biochemical requirements for antigen processing and presentation.
Complexity of the human T lymphocyte-specific cell surface antigen T3.
Authors: Borst J , Prendiville M A , Terhorst C 
Published: December 2022

Abstract
A human T lymphocyte cell surface antigen T3 was found to be involved in several functions that were specific for the cells that express this marker on their surface. We show here that several glycoproteins were found in the immunoprecipitates prepared with a monoclonal reagent anti-T3. In addition to the major glycoprotein complex of 20 kd, glycoproteins of 25 to 28 kd, 37 kd, and 44 kd were detected in immunoprecipitates. The charge heterogeneity of the 20 kd and 25 to 28 kd proteins was caused by variable sialic acid content. The 20-kd T3 glycoprotein carried several "complex-type" and endoglycosidase-H-sensitive sugar moieties. We found that the 20-kd protein could be labeled with 125I-iodonaphthylazide, a reagent that reacts with hydrophobic areas of proteins.
Hemolytic efficiency of cell-bound IgM: evidence that IgM-C1 complexes activate C4 molecules not hemolytic with homologous C2--C9.
Authors: Ejzemberg R , Borsos T 
Published: December 2022

Abstract
The hemolytic efficiency of rabbit-anti-Forssman IgM antibody depends on the source of complement components. With whole guinea pig complement as few as one in 10 IgM molecules was hemolytic; it was found that with purified guinea pig C1, C4, and C2 components and with rat late-acting components, all IgM molecules were hemolytic. Evidence indicates that the block occurred as a result of generating at least two different cell-bound C4 molecules, one of which was not competent with homologous late-acting components.
Control of IgM synthesis in the murine pre-B cell line, 70Z/3'.
Authors: Mains P E , Sibley C H 
Published: December 2022

Abstract
The murine 70Z/3 tumor resembles a pre-B cell in synthesizing only intracellular mu-chains and no detectable light chain. However, one kappa gene is already rearranged, and after overnight incubation with lipopolysaccharide (LPS), most of the cells are induced to synthesize light chain. The induced cells display IgM on their surface, but do not secrete IgM. Thus, 70Z/3 cells resemble cells poised at the pre-B cell/B lymphocyte border. We have examined synthesis and post-translational modification of mu-chains in uninduced and induced 70Z/3 cells. Isolation of mu-chains and peptide maps demonstrated that both populations synthesize intracellular forms that correspond to membrane-specific mum and secretion-specific mus chains. These intracellular forms have completed only the first of the two glycosylation steps characteristic of eukaryotic cells. After induction by LPS, L chain synthesis commences, mum and mus synthesis are both increased twofold to threefold (due to an increased rate of synthesis rather than decreased degradation), and both complex with L chain to form mu2L2 tetramers. Furthermore, the glycosylation of a subset of the mum chains is completed, and these are placed on the membrane. However, unglycosylated mu2L2 tetramers can be placed on the membrane, so glycosylation is not a requirement. These data suggest that L chain may not be sufficient for externalization of mum and mus chains. These data support the idea that the controls of membrane placement and secretion of mu chains are post-translational and that different mechanisms operate for mum and mus chains.
The requirement of specific anticapsular IgG for killing of Haemophilus influenzae by the alternative pathway of complement activation.
Authors: Tarr P I , Hosea S W , Brown E J , Schneerson R , Sutton A , Frank M M 
Published: December 2022

Abstract
Employing an in vitro bactericidal assay using C4-deficient guinea pig serum (C4D-GPS), we evaluated the ability of the alternative pathway to kill a number of strains of encapsulated and unencapsulated Haemophilus influenzae (HI). Complement activation occurred, but no bactericidal activity was observed against any of the tested HI in nonimmune C4D-GPS without detectable antibody to HI-type b (HIb) capsular polysaccharide (HIb-ps). In the presence of high-titered human anti- (type b) IgG, C4D-GPS killed the encapsulated strains. Restoration of classical pathway activity by the addition of purified C4 to C4D-GPS, which contained antibody to somatic antigens, resulted in killing of some strains of both encapsulated and unencapsulated HI. In nonimmune C4D-GPS the alternative pathway is activated but does not mediate bactericidal activity. The addition of specific high-titered anticapsular IgG results in killing of encapsulated HI by the alternative pathway in guinea pig serum.