bluuebunny/crossref_metadata_2025_split huggingface dataset:
Priming and suppression of the intestinal immune response to cholera toxoid/toxin by parenteral toxoid in rats.
Authors: Pierce N F , Koster F T 
Published: December 2022

Abstract
Parenteral immunization of rats with cholera toxoid had both priming and suppressive effects upon the antitoxin response in jejunal lamina propria to locally applied toxoid/toxin. Priming was detected when parenteral toxoid was given i.p. but not i.v. or s.c., was enhanced by Freund's adjuvant, and appeared to reflect enhanced encounter of i.p. antigen with IgA-committed lymphocytes in extra-intestinal mucosa-associated lymphoid tissue. In contrast, suppression followed parenteral toxoid given i.p., i.v., or s.c.; suppression was antigen specific and lasted at least 16 weeks. Parenteral toxoid suppressed both primary and secondary types of mucosal antitoxin responses, ultimately preventing the generation of antitoxin-containing immunoblasts from Peyer's patches. Since suppression followed parenteral immunization by routes that did not provoke mucosal priming, it was, at least in those instances, not simply a regulatory consequence of mucosal priming. These results support the notion that priming and suppression of a specific mucosal immune response are independent effects of parenteral immunization that are probably determined by the distribution of antigen to mucosa-associated and systemic lymphoid tissue, respectively.
Limiting dilution analysis of alloantigen-reactive T lymphocytes. IV. High frequency of cytolytic T lymphocyte precursor cells in MLC blasts separated by velocity sedimentation.
Authors: Maryanski J L , MacDonald H R , Cerottini J C 
Published: December 2022

Abstract
A sensitive limiting dilution microculture system was used to obtain minimal estimates of the frequency of cytolytic T lymphocyte precursor cells (CTL-P) directed against DBA/2 alloantigens, after priming of spleen cells in unidirectional mixed leukocyte cultures (MLC, C57BL/6 anti-DBA/2). The mean CTL-P frequency in day 4 to 5 MLC populations was found to be approximately 50- to 100-fold greater than the frequency in normal spleen, and up to 25% of the cells present in such MLC could be identified operationally as CTL-P. Even higher frequencies (up to 50%) of CTL-P were obtained in a population of large-sized cells separated from day 4 MLC by velocity sedimentation. Furthermore, since a strikingly quantitative correlation was observed between CTL activity and CTL-P frequency in such separated MLC populations, it is likely that mature CTL in MLC are not end cells, but can further proliferate and thus behave operationally as CTL-P.
Viral inhibition of lymphocyte mitogenesis. I. Evidence for the nonspecificity of the effect.
Authors: Wainberg M A , Israel E 
Published: December 2022

Abstract
We have investigated the mechanism(s) whereby virus particles, when co-incubated with lymphocytes, are able to abrogate mitogen- and alloantigen-driven cell proliferation. Our data indicate that this inhibition is entirely nonspecific with regard to its induction; similar results can be obtained by using any of several different types of infectious virus particles or viruses whose infectivity had been destroyed by irradiation with ultraviolet light. Furthermore, we show that plasma membranes vesicles, which approximate viruses in size, and which are derived from normal cells, can also impede lymphocyte proliferative responsiveness. In the mixed lymphocyte culture (MLC) reaction, the inhibitory effect is apparently due to the action of viruseith virus can inhibit the mitogen-induced proliferation of resh syngeneic spleen cells, even if added to the latter at a ratio as low as 1:250. These results suggest that virus particles induce the activation of suppressor lymphocytes which in turn act on those cells which would otherwise be responsive in mitogenesis assays and in the MLC.
The suppression of Epstein-Barr virus infection in vitro occurs after infection but before transformation of the cell.
Authors: Thorley-Lawson D A 
Published: December 2022

Abstract
It has been demonstrated that T cells from humans can suppress the transformation of EBV-infected B cells in vitro. In this paper, studies are presented on the mechanism of the suppression. The T cells do not act against the virus itself nor the infection process. They appear to suppress the outgrowth of B cells after they are infected but before they are transformed. The T cells are much less effective in suppressing the outgrowth of the B cells once the latter have transformed (24th post-infection). The significance of these observations to EBV infection and other forms of T cell-mediated anti-EBV immunity is discussed.
Mechanisms of immune lysis. I. Physiological distinction between target cell death mediated by cytotoxic T lymphocytes and antibody plus complement.
Authors: Russell J H , Masakowski V R , Dobos C B 
Published: December 2022

Abstract
The pattern of progressive release of cytosolic (52Cr) and nuclear (125IUdR) labels from normal or tumor cells being lysed by CTL is strikingly different from the pattern observed when similar cells are lysed by Ab + C or hypotonic shock. We propose that these differences reflect physiologic differences in the lytic events associated with Ab + C- and CTL-mediated cell death.
Separation of a serum-derived tumoricidal factor from a helper factor for plaque-forming cells.
Authors: Männel D N , Farrar J J , Mergenhagen S E 
Published: December 2022

Abstract
C3H/HeN mice administered BCG followed by lipopolysaccharide 14 days later released into their serum a cytotoxic factor for tumor cells and a factor that restored the anti-SRBC plaque-forming cell response of nude mouse spleen cells (helper activity). Gel filtration of serum containing the cytotoxic and the helper activities indicated that both factors exhibited an apparent m.w. of 125,000 to 150,000. The helper activity was also found at lower m.w. (60,000 and 13,000) suggesting the possibility that this factor existed in aggregated forms. Gel filtration of ammonium sulfate (40 to 60% saturation) precipitated serum in a high ionic strength buffer (1.6 M NaCl) resulted in shifts in the apparent m.w. of both factors. The cytotoxic factor now exhibited a m.w. of 55,000. The helper activity eluted with an apparent m.w. of 13,000, and thus was clearly separated from the cytotoxic factor. The helper activity was further shown to co-elute with macrophage-derived lymphocyte activating factor (LAF). This as well as other data represent the first demonstration of in vivo produced LAF.
A monoclonal antibody reactive with the human cytotoxic/suppressor T cell subset previously defined by a heteroantiserum termed TH2.
Authors: Reinherz E L , Kung P C , Goldstein G , Schlossman S F 
Published: December 2022

Abstract
A hybridoma-secreting monoclonal antibody was produced from the spleen cells of a mouse immunized with human thymocytes. This hybridoma antibody, termed OKT5, was reactive by indirect immunofluorescence with 80% of human thymocytes but only 20% of peripheral blood T cells. Moreover, OKT5 was unreactive with normal B cells, null cells, and macrophages at any dilution tested. A similar pattern of reactivity was seen with an equine antiserum to human thymocytes termed anti-TH2. Fluorescence-activated cell sorting demonstrated that the OKT5 antibody reactivity on peripheral T cells was restricted to the majority of the previously defined TH2+ subpopulation. In functional studies, the OKT5+ subset, like the TH2+ subset, proliferated well to the mitogen Con A and to alloantigens, and contained cytotoxic effector cells after sensitization in MLC, and suppressor effector cells after activation with Con A. In addition, like the TH2+ T cell, the OKT+ T cell was virtually unresponsive to soluble antigen. Thus, the OKT5 monoclonal antibody is reactive with the cytotoxic/suppressor T cell subset. OKT5 should provide an important probe to assess the status of suppressor cells in human disease.
Dissociation of differentiation and proliferation in the primary induction of cytolytic T lymphocytes by alloantigens.
Authors: MacDonald H R , Lees R K 
Published: December 2022

Abstract
The requirement for DNA synthesis in the induction of cytolytic T lymphocytes (CTL) by alloantigens has been investigated. C57BL/6 splenic T cells purified by passage on nylon wool columns were stimulated in vitro in mixed leukocyte culture (MLC) and assayed for cytotoxicity against 51Cr-labeled target cells. With this system, CTL activity was detectable after 24 hr of MLC and reached high levels after 48 hr. Addition of cytosine arabinoside (ARA-C) or hydroxyurea to such cultures at concentrations that were sufficient to inhibit DNA synthesis by greater than 98% did not reduce CTL activity measured after 24 hr; however, the increase in activity that occurred between 24 and 48 hr in control cultures was strongly reduced (or abolished) by these drugs. Velocity sedimentation analysis of MLC cells activated for 48 hr in the presence of ARA-C further revealed that CTL precursor lymphocytes had enlarged into medium- to large-sized CTL under these conditions. These studies provide direct evidence that the primary induction of CTL by alloantigens can be dissociated into a differentiation step, which occurs within 24 hr in the absence of DNA synthesis and is accompanied by blast transformation, and a subsequent proliferation.
Antibodies to murine leukemia virus gp70 and p15(E) in sera of BALB/c mice immunized with syngeneic chemically induced sarcomas.
Authors: Klitzman J M , Brown J P , Hellström K E , Hellström I 
Published: December 2022

Abstract
The sera of BALB/c mice immunized with syngeneic methylcholanthrene-induced sarcomas commonly contain antibodies that react with the immunizing tumor line and also with other chemically induced sarcomas. Three lines of evidence suggest that the cross-reactive antibodies are directed against antigenic determinants of gp70 and p15(E), envelope proteins of endogenous murine leukemia virus (MuLV). 1) The antibodies bind only to sarcomas expressing MuLV antigens, 2) they are removed by absorption with purified MuLV antigens, and 3) they precipitate proteins identified as gp70 and p15(E) from 125I-labeled sarcoma cell lysates.
Stability of DNA/anti-DNA complexes. III. Kinetic control of immune complex size.
Authors: Taylor R P , Waller S J , Haden C , Addis D J 
Published: December 2022

Abstract
The Farr assay and sucrose gradient ultracentrifugation were used to study the importance of kinetic factors on the size of antibody/DNA immune complexes prepared from SLE sera and dsDNA. We have found that significantly different numbers and sizes of antibody/DNA immune complexes can be formed by varying the time course of addition of a given amount of DNA to an SLE serum. For example, the introduction of additional DNA to a preincubated antibody-DNA system does not lead to reequilibration of that system with respect to the amount of DNA bound or the size of the complexes formed even after 1 hr at 37 degrees C. The potential implications of these observations with respect to the pathogenesis of SLE is discussed.
IgA1 proteases from Haemophilus influenzae, Streptococcus pneumoniae, Neisseria meningitidis, and Streptococcus sanguis: comparative immunochemical studies.
Authors: Kilian M , Mestecky J , Kulhavy R , Tomana M , Butler W T 
Published: December 2022

Abstract
IgA1 proteases from H. influenzae, N. meningitidis, S. pneumoniae, and S. sanguis were compared with respect to site of cleavage in the IgA1 molecule and EDTA sensitivity. Proteases from S. sanguis and S. pneumoniae cleaved the Pro (227)-Thr (228) bond within the hinge region of the alpha 1 chain and were inhibited by EDTA. H. influenzae IgA1 protease cleaved the Pro (231)-Ser (232) peptide bond. The activity of IgA1 proteases from H. influenzae and N. meningitidis was unaffected by EDTA. Purified and denatured alpha 1 chain was cleaved only in the hinge region. Other component chains of secretory IgA (secretory component, light and J chains) were not susceptible. In addition to IgA1 protease, S. pneumoniae released exo- and endoglycosidases that removed a considerable portion of carbohydrate side chains of IgA1; this activity was absent from crude IgA1 protease preparations of the other three bacterial species. Association in vitro of polymeric IgA1 with SC did not inhibit the degradation of IgA1 proteases. The considerable resistance of secretory IgA to cleavage by IgA1 proteases may be explained in part by the presence of IgA1 protease-neutralizing antibodies in secretory IgA.
Effect of cyclosporin A on human lymphocyte responses in vitro. I. CsA allows for the expression of alloantigen-activated suppressor cells while preferentially inhibiting the induction of cytolytic effector lymphocytes in MLR.
Authors: Hess A D , Tutschka P J 
Published: December 2022

Abstract
The effect of cyclosporin A (CsA) on in vitro human lymphocyte responses was assessed. CsA suppressed in a dose-dependent fashion, the lymphocyte response to stimulation with mitogens and with alloantigens in primary and secondary mixed lymphocyte reactions (MLR). In contrast, the action of cytolytic effector lymphocytes was not affected by this compound. Time-course kinetic studies indicated that the mitogen response was markedly dependent on the time of addition of CsA to the cultures. Inhibition of the lymphocyte response to alloantigens was less dependent upon the time of addition of CsA to the cultures. Preincubation with CsA did not markedly affect the ability of the lymphocytes to respond to mitogens and alloantigens, nor was there an overt cytotoxic action. In addition, CsA was shown to have a differential effect on the activation of cytotoxic and suppressor lymphocyte subpopulations in primary MLR. The induction of cytolytic lymphocytes was markedly suppressed by minimal amounts of CsA, whereas the induction of alloantigen-activated suppressor cells was much less inhibited by this agent. These results suggest that CsA treatment favors the induction of suppressor cell mechanisms as opposed to cytolytic effector cells in primary MLR. This may account for the ability of this drug to establish transplantation tolerance in vivo.
T cell maturation: thymocyte and thymus migrant subpopulations defined with monoclonal antibodies to the antigens Lyt-1, Lyt-2, and ThB1.
Authors: Scollay R , Weissman I L 
Published: December 2022

Abstract
The phenotypes of thymus cells for the antigens Lyt-1, Lyt-2 and ThB have been analyzed by using immunofluorescence techniques. Cells throughout the intrathymic maturation sequence have been tested, including the primitive subcapsular lymphoblasts, all size classes of cortical and medullary thymocytes, and thymus cell emigrants. ThB antigen is not detectable on migrant cells, but all subpopulations in the thymus are subdivided into two categories, bright and dull. Thus, it is possible that the bright and dull phenotypes represent a lineage specific rather than a stage-specific marker, at least inside the thymus. The Lyt-defined thymocyte subclasses Lyt1+2+-(Lyt-1) and Lyt 1+2+ (lyt-1,2) are also both represented in all subpopulations, including subcapsular lymphoblasts. This suggests that they may represent two separate lineages, and that the Lyt-12(3) class is not a precursor of the Lyt-1 class, although the possibility of a very early Lyt-(12(3) cell precursor common to both lines cannot be ruled out.
Idiotypic analysis of anti-GL phi antibodies. I. Identification and strain distribution of GL-1 idiotypes.
Authors: Ju S T , Benacerraf B , Dorf M E 
Published: December 2022

Abstract
We utilized both the inhibition of antigen binding and direct idiotype binding methods to identify a new set of common idiotype determinants on anti-GL antibodies of various mouse strains. Three anti-idiotypic antisera, each prepared against individually purified B10.WB anti-GL phi antibodies, were able to detect antibody-combining site-associated common idiotypic determinants, designated GL-1 idiotype(s), in antisera with GLT-binding activity obtained from all mouse strains except strains bearing Igh-1e allotype. Anti-GL phi antisera obtained from rabbits, guinea pigs, and rats did not express detectable levels of GL-1 idiotypes. Nonresponder mice to GL phi, upon immunization with GL-F gamma G or GL phi-F gamma G produced anti-GL antibodies expressing GL-1 idiotypes. Although the magnitude of the immune response to various GL-containing polymers is controlled by distinct Ir genes, the common GL-related antigenic determinants on these polymers are able to induce anti-GL antibodies with GL-1 idiotypic specificities.
Definitive mapping of the immune response gene(s) for (T,G)-A--L to the I-A subregion.
Authors: Markman M , Dickler H B 
Published: December 2022

Abstract
Mice of strains B10, B10.A, B10.A(4R), B10.A(5R), and the new recombinant inbred strain B10.MBR (H-2 genotype Kb, Ik, Sk. Dq) were immunized with (T,G)-A--L and the primary (total and IgM component), and secondary antibody responses were measured by using radioimmunoassays. B10 and B10.A(5R) were high responders, whereas B10.A, B10.A(4R), and B10.MBR were low responders to (T,G)-A--L. Based on the genotypes of the strains utilized, the immune response gene(s) for (T,G)-A--L is located in the I-A subregion of the H-2 complex. The data are consistent with the concept that Ia antigens are Ir gene products.
MLC-derived human helper factor(s) that promote B cell differentiation: induction, functional characterization, and role of Ia antigens.
Authors: Friedman S M , Irigoyen O H , Gay D , Chess L 
Published: December 2022

Abstract
Utilizing a PFC assay to quantitate the polyclonal activation of human peripheral blood B lymphocytes, we have investigated the induction and functional activity of MLC-derived human helper factor(s). Our data demonstrate that highly purified responder T cells, but not B or null cells, are required for the elaboration of MLC helper factor(s) that trigger the in vitro differentiation of B lymphocytes into PFC. Helper factor can trigger B cell maturation in the absence of helper T cells, since complement- (C) mediated lysis of the small (less than 5%) fraction of T cells present in anti-F(ab)2 immunoabsorbent column purified B cell population eliminates the PWM induced, but not the helper factor-induced PFC response. Responder T cells required for helper factor production do not bear surface membrane Ia, since alpha p23,30 + C treatment of this population does not affect helper factor generation. In contrast, alpha p23,30 + C treatment of the allogeneic stimulator cell population eliminates helper factor production. Taken together, these results demonstrate that interaction between Ia-bearing stimulator cells and Ia- responder T cells is required for the production of MLC-derived helper factor. In additional experiments, we determined that alpha p23,30, in the absence of C, totally abrogates the PFC response triggered by MLC helper factors. This result suggests an important role for Ia antigens in the functional activity of preformed helper factor molecules.
In vitro growth of cytotoxic human lymphocytes. II. Use of T cell growth factor (TCGF) to clone human T cells.
Authors: Lotze M T , Strausser J L , Rosenberg S A 
Published: December 2022

Abstract
Soft agar and limiting dilution techniques utilizing human T cell growth factor (TCGF) have been developed to clone human lymphoid cells with high cloning efficiency. TCGF has been used for the continued growth and expansion of lymphoid populations derived from single T cells, and the cytotoxic specificity of individual clones has been repeatedly examined. An analysis of clones derived from human lymphocytes sensitized to allogeneic determinants in vitro reveals significant polymorphism in lytic recognition when tested against HLA typed targets. This pattern of reactivity remained constant over the 2 months of continuous culture. These methods should be capable of dissecting and analyzing the fine specificity of the T cell response.
The lipid A moiety of lipopolysaccharide is specifically bound to B cell subpopulations of responder and nonresponder animals.
Authors: Gregory S H , Zimmerman D H , Kern M 
Published: December 2022

Abstract
Employing autoradiography to detect [125I]-lipid A binding splenocytes and immunofluorescence to identify splenic B cells, it was observed that only a subpopulation of B cells bound lipid A. In contrast, non-B cells, including T cells and macrophage cells, exhibited either relatively little or no lipid A binding. LPS-responder and LPS-nonresponder substrains of mice exhibited essentially the same distribution of bound [125I]-lipid A among B cell subpopulations. Approximately 25% of the B splenocytes obtained from the LPS-responsive C3H/HeN substrain or from the LPS-nonresponsive C3H/HeJ, C57BL/10ScCR and C57BL/10ScN substrains bound [125I]-lipid A. On the other hand, 60% of the B splenocytes from both high- and low-responder mice derived from the CBA strain exhibited [125I]-lipid A binding. Taken in conjunction with the findings of other workers, these results are consistent with the possibility that the genetic defect in nonresponder mice is related to a lipid A triggering event rather than to lipid A binding.
Functional discrimination by human monocytes between their C3b receptors and their recognition units for particulate activators of the alternative complement pathway.
Authors: Czop J K , Austen K F 
Published: December 2022

Abstract
A trypsin-sensitive recognition unit for ingestion of particulate activators of the human alternative complement pathway is present on human monocytes and persists during 48 hr of culture in synthetic medium. Further, after inactivation by trypsin, the recognition unit for activators of the alternative pathway is fully regenerated in terms of function during the 48 hr of culture. In contrast, the C3b receptor on human monocytes is relatively trypsin resistant and is lost during 48 hr of culture, as assessed by its capacity to mediate C3b-dependent immune adherence or enhanced phagocytosis. The prior immune adherence of the monocytes to C3b-bearing particles does not alter the capacity of the monocytes to ingest a particulate activator, and the ingestion of particulate activators does not induce phagocytosis of the rosetted C3b-bearing particles. Thus, the functions linked to the recognition of C3b and of particulate activators of the alternative pathway are expressed independently by monocytes when the determinants reside on separate particles. When the determinants are expressed by the same particle, such as an activator bearing C3b, the monocytes exhibit a synergistic response through their distinct recognition units for C3b and particulate activators of the alternative pathway.
The response of human lymphocyte subpopulations to measles, mumps, and vaccinia viral antigens.
Authors: McFarland H F , Pedone C A , Mingioli E S , McFarlin D E 
Published: December 2022

Abstract
A proliferative assay employing virus-infected, fixed monolayers was used to examine the response of PBL and lymphocyte subpopulations to measles, mumps, and vaccinia viruses. The response obtained in this assay was shown to be virus specific. In individuals previously exposed to mumps or vaccinia viruses, a substantial proliferative response was elicited. In contrast, only a small number of individuals responded to measles virus even though they were seropositive for this virus. In the responders, the proliferation to each of the viruses was essentially limited to the T cell fraction and more specifically to the IgG Fc receptor-bearing T cell, the T gamma cell. The response was not dependent on the presence of antiviral antibody in the assay and was therefore apparently not related to the ADCC activity of the T gamma population. The failure of the T non-gamma cell to proliferate was not due to HLA restriction since a response in this cell population could not be elicited on infected autologous skin fibroblasts. The functional significance of the T gamma cell response is not established although a possible immunoregulatory role is considered.