bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modulation of F1 cytotoxic potentials by GvHR. Host- and donor-derived cytotoxic lymphocytes arise in the unirradiated F1 host spleens under the condition of GvHR-associated immunosuppression.
Authors: Kubota E , Ishikawa H , Saito K 
Published: December 2022

Abstract
As an approach to dissect complex cellular events that lead to GvHR-associated immune disorders, we followed cytotoxic activities, including NK cytotoxicity, in the spleens of unirradiated F1 hosts undergoing GvHR induced by parental spleen cells. Spleen cells of (B10 X DBA/2)F1 or (B10 X AKR/J)F1 hosts undergoing GvHR induced by parental B10 spleen cells displayed a prompt and marked increase in NK cell activity within 36 hr, and the heightened activity lasted until day 8. The activity then declined abruptly and disappeared on day 12 of GvHR. Inversely, donor B10-derived CTL specifically directed to the opposite parental alloantigens of the F1 hosts emerged in these F1 host spleens on day 8, and the CTL activity reached a peak on day 12 when the host NK cell activity disappeared. During the period that the donor-derived anti-host CTL were present, these F1 host spleen cells lost not only NK cell activity but also the ability to mount in vitro CTL responses. In contrast, the respective F1 strain mice undergoing GvHR induced by the parental DBA/2 or AKR/J spleen cells showed only transient but marked increases in NK cell activity during the initial 36 hr, and then the activity decreased gradually to return to the normal level on day 10. In such GvHR F1 host spleens, donor-derived CTL could never be detected, and the spleen cells showed normal in vitro CTL responsiveness during the entire observation period of 16 days. These results are discussed from the viewpoint of genetically defined cellular events that lead to the GvHR-associated immune disorders.
Definition of a "trigger" stage in the NK cytolytic reaction sequence by a monoclonal antibody to the glycoprotein T-200.
Authors: Targan S R , Newman W 
Published: December 2022

Abstract
The monoclonal antibody 13.1 recognizes an epitope on the T-200 glycoprotein and blocks natural killer (NK) lysis of the erythroleukemia target K562, but not of the acute lymphoblastic leukemia T cell target Molt-4. The inhibitory effect is at the killer cell level and not the target cell level, which suggests that 13.1 may react with a receptor on NK cells. This hypothesis was tested in assays to delineate precisely where in the NK cytolytic reaction sequence 13.1 interferes with lysis; 13.1 did not block initial NK-target cell interaction as measured in a target binding cell assay. With the use of a Ca++ pulse technique, 13.1 did not block any events occurring during Ca++-dependent programming. If the antibody was added after conjugate formation but before the addition of CaCl2 to initiate programming, however, full inhibition of NK lysis occurred. Therefore, 13.1 antibody defines a distinct stage in the NK reaction sequence that links target binding to the initiation of calcium-dependent programming events. NK cell binding alone is not sufficient to trigger lytic events, and the presence of a second structure or a distinct portion on a single structure is required to trigger lysis. We show that 13.1 blocks the ability of K562 to inhibit NK killing of Molt-4 in a cold target inhibition assay. Therefore, despite the fact that 13.1 does not disrupt conjugate formation, NK specificity may exist at a post-binding site rather than at the initial NK-target binding interaction. Our data suggest that the T-200 glycoprotein on NK cells triggers the initiation of the lytic events.
Determination of the optimal human cell lines for development of human hybridomas.
Authors: Abrams P G , Knost J A , Clarke G , Wilburn S , Oldham R K , Foon K A 
Published: December 2022

Abstract
Six human cell lines were compared with each other and with murine myeloma NS-1 as to their sensitivity to HAT medium and their ability to form hybrids with human lymphocytes, secret monoclonal immunoglobulin, clone, and maintain detectable levels of monoclonal immunoglobulin secretion for a period of time after fusion. Fusion efficiencies varied from 0 to 50%, and the incidence of immunoglobulin secretion ranged between 1 and 78% of the hybrids. Immunoglobulin secretion of cloned hybrids varied from 0.8 to 1.6 micrograms/ml/10(6) cells among the human-human hybrids and was 2.4 micrograms/ml/10(6) cells by the human-mouse hybrid. Among the lines tested, UC729-6 and HF2 appeared optimal for pursuing further studies with human-human hybridomas. In addition, although only a small percentage of hybrids were produced with HMy2, a very high percentage secreted immunoglobulin, so that this line also warrants further investigation to improve the efficiency of hybrid formation. Implications for specific monoclonal antibody production and for therapy of leukemias and lymphomas by anti-idiotype antibodies are discussed.
Fine specificity of the in vitro antibody response to influenza virus by human blood lymphocytes.
Authors: Mitchell D M , Callard R E 
Published: December 2022

Abstract
The fine specificity of anti-influenza antibody produced in vitro by human PBM stimulated with different strains of influenza virus was examined by competition binding in solid phase enzyme immunoassay. Most of the antibody produced in vitro is directed to strain-specific or cross-reactive determinants on the hemagglutinin molecule. The extent of cross-reactivity is dependent on the strain of virus used to stimulate PBM as well as the individual tested and presumably on his previous exposure to influenza viruses. PBM from some individuals produced antibody that bound to the stimulating strain of influenza virus but not to other strains of the same subtype. In other individuals, antibody was produced in vitro that cross-reacted with all viruses in the same subtype (e.g., H3N2; A/X31, A/X47, and A/Texas) but did not bind to other (H2N1 or H1N1) subtypes, and in a few individuals, extensive cross-reaction between subtypes was seen. The presence of antibody to hemagglutinin in these culture supernatants was confirmed by competition binding to highly purified hemagglutinin. This in vitro culture system allows the immunologic memory of individuals to a wide range of stimulating virus strains to be examined simultaneously in terms of specificity of the antibody response by human PBM to influenza virus after natural infection or immunization.
Role of macrophage-myelin basic protein interaction in the induction of experimental allergic encephalomyelitis in Lewis rats.
Authors: Carbone A M , Ovadia H , Paterson P Y 
Published: December 2022

Abstract
Stimulated peritoneal exudate cells (PEC) containing activated macrophages (M phi) of Lewis (Le) rats were exposed for 1 hr in vivo or in vitro to radioiodinated soluble myelin basic protein (MBP) or MBP incorporated into magnetic microspheres (MBP-microspheres). The uptake by M phi of the dose of microsphere-bound MBP averaged 6.2%, whereas the average uptake of soluble MBP was 0.17%. Naive rats were sensitized with M phi-associated MBP or M phi-associated MBP-microspheres via the hind footpads without the aid of conventional immunologic adjuvants. Draining lymph node cells (LNC) or spleen cells from sensitized rats were cultured for 3 days with guinea pig MBP (GPMBP) alone or in combination with concanavalin A (Con A), then injected i.v. into naive recipients. Clinical signs of experimental allergic encephalomyelitis (EAE) appeared 6 days after transfer of LNC or spleen cells, and typical CNS lesions were seen in recipients sacrificed 10 to 14 days after transfer. The challenge of MO-MBP-sensitized rats with MBP-CFA resulted in severe clinical signs of EAE marked by an accelerated onset of neurologic symptoms.
Alloreactive cloned T cell lines. VII. Comparison of the kinetics of IL 2 release stimulated by alloantigen or Con A.
Authors: Ely J M , Fitch F W 
Published: December 2022

Abstract
A cloned T amplifier cell, designated L2, was shown previously to release several lymphokine activities, including IL 2, following stimulation with either alloantigen or concanavalin A (Con A). However, the responses induced by the two stimuli differ significantly. When high numbers of L2 cells were stimulated with Con A, greater amounts of IL 2 were released whereas stimulation of high numbers of L2 cells with alloantigen resulted in the release of less than optimal levels of IL 2. IL 2 levels as high as 1500 units/ml were reached with Con A. When stimulated with alloantigen, the release of L2 cells was followed by proliferation. When stimulated with Con A, the cells did not proliferate. The inhibitory effect was related to the length of exposure of L2 cells to the lectin and could be avoided by removing the excess Con A from cultures 3-6 hours after stimulation. Thus, a brief exposure of L2 cells to Con A was sufficient to cause the release of high levels of lymphokine activities and permit the L2 cells to proliferate in a pattern similar to that after stimulation with alloantigen. These results are consistent with the hypothesis that the lectin, Con A, acts as a mitogen for cloned murine amplifier T cells only indirectly by triggering the release of growth factors which then promote cell proliferation.
Structural identity of the TL antigen homologues derived from strain 2 and strain 13 guinea pigs.
Authors: Surratt R S , Abruzzini L N , Zacheis M P , Cigen R , Schwartz B D 
Published: December 2022

Abstract
Strain 2 and strain 13 guinea pig thymocytes have been shown to bear a molecule that by several criteria appears to be a homologue of the murine TL antigen. The existence of a TL polymorphism in the mouse system as evidenced by TL- strains and various TL phenotypes in TL+ strains prompted a study to determine if a similar polymorphism could be demonstrated in the guinea pig system. By using two-dimensional gel electrophoresis, the thymocytes of a third inbred strain, DHCBA, were shown to bear a TL antigen, and the TL antigens of strains 2 and DHCBA were shown to give identical patterns of spots. A biochemical comparison of the strain 2 and strain 13 TL antigen heavy chains by tryptic and chymotryptic peptide mapping demonstrated that these molecules have identical peptides. Thus, no polymorphism could be demonstrated within the guinea pig TL system for the three inbred strains studied. Comparative tryptic peptide mapping of the guinea pig TL and class I B.1+S antigens demonstrated 43% homology, significantly higher than that reported for murine H-2 and TL antigens. These results provide suggestive evidence that the gene duplication giving rise to the genes determining the class I and TL antigens may have occurred more recently in the guinea pig than in the mouse.
The presence of NK alloantigens on cloned cytotoxic T lymphocytes.
Authors: Brooks C G , Burton R C , Pollack S B , Henney C S 
Published: December 2022

Abstract
A panel of sera raised against NK-1.1 and NK-2.1 alloantigens was tested for reactivity against a panel of cloned antigen-dependent CTL lines. By using indirect immunofluorescence and flow cytofluorimetry, weak, but clear and consistent, reactivity was found on all CTL. Concordant with the genetics of NK alloantigens, C57BL/6-derived clones were reactive with anti-NK-1.1 and anti-NK-2.1 sera, whereas CBA-derived clones were reactive with anti-NK-2.1 sera but not with anti-NK-1.1 sera. Cloned CTL lines were also able to partially and specifically absorb the antibodies from NK alloantiserum that reacted with splenic NK cells. These results indicate that cloned CTL lines express at least some of the NK alloantigen determinants present on splenic NK cells and have important implications regarding the relationship of CTL and NK cells.
Role of polymorphonuclear cells in Chagas' disease. I. Uptake and mechanisms of destruction of intracellular (amastigote) forms of Trypanosoma cruzi by human neutrophils.
Authors: Villalta F , Kierszenbaum F 
Published: December 2022

Abstract
The ability of human polymorphonuclear cells (PMN) to take up and destroy intracellular forms of Trypanosoma cruzi (AMA) was investigated as a part of our efforts to elucidate the mechanisms of clearing of these parasites from infected tissues. PMN were found to take up AMA and destroyed parasites were seen after 30 min of cell-parasite interaction. Under our experimental conditions, the rate of uptake of AMA by PMN was maximal during the first 30 min of interaction. AMA were found to be located and destroyed inside the phagolysosomal vacuoles of PMN. The parasite was never found outside these vacuoles despite electron microscopic examination of numerous preparations derived from several experiments. Intracellular destruction of AMA by PMN was visible by electron microscopy and could be monitored by measuring the release of 3H-labeled substances by PMN that had ingested radiolabeled AMA. PMN incubated after removal of unbound parasites destroyed over 90% of the ingested organisms within 3 hr and close to 99% after 12 hr. In cellfree systems, 44% of the AMA were destroyed in the presence of 10(-4) M H2O2 and all of the parasites died at 10(-3) M. Addition of lactoperoxidase and iodide resulted in 100% killing at 10(-5) M H2O2. These mechanisms appeared to be involved in the lysis of AMA by PMN since both H2O2 and peroxidase activity were demonstrated to be present in PMN vacuoles containing the parasite. Addition of NaN3, KCN (inhibitors of myeloperoxidase activity) or catalase (to decompose H2O2) caused a marked reduction in the extent of AMA killing by PMN. Xanthine oxidase was toxic for the AMA in the presence of acetaldehyde. This microbicidal activity was inhibited by catalase but not by heat-inactivated catalase or by reagents that scavenge the intermediate products of reduction of molecular oxygen, O - X 2, X OH, and 1O2. These results suggest that PMN have the potential of clearing AMA liberated in infected chagasic tissues and that parasite killing within the phagolysosomal vacuoles is mediated by myeloperoxidase activity and H2O2.
Genetic polymorphism of human C4-binding protein.
Authors: de Cordoba S R , Ferreira A , Nussenzweig V , Rubinstein P 
Published: December 2022

Abstract
Two different forms of human C4-bp, C4-bp A and C4-bp B, have been identified by isoelectric focusing (IEF) of neuraminidase-treated EDTA-plasma samples. Family studies demonstrate Mendelian segregation of these forms, indicating that they are under gentic control. This conclusion is supported by IEF analysis of the two variants purified by affinity chromatography. Under completely denaturing conditions, C4-bp B was found to be composed of two subunits that focused at different pH, whereas C4-bp A contains only the more basic one. These results suggest that a single autosomal locus with at least two codominant alleles coding for the subunits controls the IEF variation of C4-bp in humans. The allele designated C4BP*1 codes for a subunit that, after neuraminidase treatment, focuses at pH = 6.65. The allele C4BP*2 codes for a different subunit that focuses at pH = 6.60. The C4-bp A phenotype corresponds to the genotype C4BP*1,C4BP*1 and the phenotype C4-bp B to the genotype C4BP*1,C4BP*2. The phenotype corresponding to the C4BP*2,C4BP*2 homozygous genotype has not been encountered thus far. Initial linkage data indicate that the C4BP locus is not closely linked to either the HLA or to the C3 loci.
Recognition of influenza-infected cells by cytolytic T lymphocyte clones: determinant selection by class I restriction elements.
Authors: Vitiello A , Sherman L A 
Published: December 2022

Abstract
The fine specificity of virus recognition by influenza A/PR8/34(H1N1)-specific cytolytic T lymphocyte (CTL) clones was analyzed with the use of a panel of syngeneic target cells infected with five heterologous influenza A strain viruses. Forty-five H-2 D-end-restricted CTL clones from B10.A(5R) responders (Dd,Ld) demonstrated 14 different patterns of recognition. Many of these clonotypes were able to distinguish between closely related viruses of the same subtype. Such discriminatory capacity, however, was often accompanied by cross-reactivity against a distantly related viral subtype. This supports the contention that virus-specific CTL see different structures than do virus-specific antibodies. A similar analysis of the fine specificity of 60 Db-restricted clones from C57BL/6 responders was performed. The vast majority of this response was composed of clonotypes not observed in the B10.A(5R) response. In addition, the hierarchy of relatedness between the virus strain used for immunization and the various heterologous viruses was different in C57BL/6 and B10.A(5R). In contrast, the D-end-restricted response of Balb/c (Dd,Ld) demonstrated clonotypes similar to those found in B10.A(5R). These data suggest that determinant recognition in an anti-viral CTL response is a function of the H-2 restricting elements, and this is discussed in the context of determinant selection by class I molecules.
A comparison of the neonatal tolerance-inducing capacities of H-2 class I and class II antigens.
Authors: McCarthy S A , Bach F H 
Published: December 2022

Abstract
We have investigated the abilities of murine major histocompatibility complex-encoded antigens to induce in vitro hyporeactivity of T lymphocytes when these antigens are injected neonatally. Class I molecules, presented on F1 donor cells having an H-2 K or D region difference from recipients, can readily induce tolerogen-specific cytotoxic T cell hyporeactivity; as few as 1 X 10(6) neonatally injected donor cells suffice. In contrast, class II molecules, presented on F1 donor cells having an H-2 I region difference from recipients, can induce tolerogen-specific helper T cell hyporeactivity only when at least 1 X 10(7) neonatally injected donor cells are used, and then only in some of these recipients. Results from another in vitro assay system, taken in conjunction with these data, indicate that the molecular class of the tolerizing disparity, rather than the effector function of the responding cell type assayed, may be the most important factor in controlling the ease with which neonatally induced alloantigen tolerance can be achieved. In each type of tolerance described here, the hyporeactivity seen is antigen specific, in its induction and its expression; the implications of this fact for considerations of possible mechanisms of tolerance maintenance are discussed.
Clonal abortion of bone marrow T cell precursors: T cells acquire specific antigen reactivity prethymically.
Authors: Chervenak R , Cohen J J , Miller S D 
Published: December 2022

Abstract
Lethally irradiated (900 R) mice were reconstituted with bone marrow cells from syngeneic donors that had been tolerized 2 to 3 wk earlier to either DNP or TNP compounds. Five weeks after reconstitution, these animals were tested for their ability to mount a delayed hypersensitivity (DH) response to the tolerizing haptens. Recipient mice were specifically tolerant to the hapten that was used to induce tolerance in the marrow donor. Mixing experiments in which mice were reconstituted with marrow from DNP-tolerant and TNP-tolerant donors showed no indication of active suppression or effective antigen carry-over in this system. This observation held true even in experiments in which mice were reconstituted with a mixture of marrow from tolerant and normal donors at a ratio of 5:1. Thus the reduced responsiveness in recipient mice seemed to be due to the functional elimination of hapten-responsive T cell precursor (pre-T) clones. Recipient unresponsiveness was also shown to be MHC restricted. Maintenance of unresponsiveness appeared to be due to the restricted access of regenerating pre-T cell clones to the maturational influence of the recipient's thymus.
Differentiation of B lineage cells from liver of neonatal mice: generation of immunoglobulin isotype diversity in vitro.
Authors: Calvert J E , Kim M F , Gathings W E , Cooper M D 
Published: December 2022

Abstract
The development and differentiation of B cells expressing different immunoglobulin (Ig) isotypes was studied in cultures of murine neonatal liver cells. Before culture, 5 to 15% of the liver cells were mu + pre-B cells; 1 to 3% had surface IgM and less than 0.1% had slgG. During 4 days in culture the number of pre-B cells declined, whereas the number of IgM B cells increased greater than 20-fold; IgG B cells also increased in number. Of the four subclasses, IgG3+ and IgG2b+ cells predominated, each representing 3 to 10% of the total B cells at day 4. IgG1+ and IgG2a+ cells were present in lower numbers, representing 1 to 5% and 0.3 to 2.5% of B cells, respectively. Most IgG+ cells also expressed sIgM. Only a minority (less than 10%) of the sIgM+ cells were sIgD+, and most sIgG+ cells were sIgD-. Few T cells were present in these cultures (less than 0.5% in newborn liver), and sIgG+ cells were generated in normal frequencies in cultures of cells from nude mice. The numbers of B cells expressing each IgG subclass were similar in cultures from athymic nu/nu mice, nu/+ heterozygous littermates, and normal BALB/c mice. Plasmablasts and plasma cells appeared over a 14-day culture interval, and these expressed cytoplasmic IgM, IgG3, IgG1, IgG2b, IgG2a, and IgA. Measurable amounts of the first four isotypes were detected in the culture supernatants by radioimmunoassay. These results indicate that neonatal B cells can undergo isotype switching in the absence of T cell help, and that the expression of sIgD may not be a prerequisite for cells to switch Ig isotypes.
Dissociation between macrophage tumoricidal capacity and suppressive activity: analysis with macrophage-defective mouse strains.
Authors: Boraschi D , Pasqualetto E , Ghezzi P , Salmona M , Bartalini M , Barbarulli G , Censini S , Soldateschi D , Tagliabue A 
Published: December 2022

Abstract
Macrophages (M phi diameter) from three mouse strains with genetically distinct M phi diameter deficits (C3H/HeJ, A/J, and P/J) were unable to develop high cytolytic and cytotoxic activity against tumor cells in vitro when exposed to agents (MAF and IFN-beta) that strongly increased the tumoricidal capacity of M phi diameter from nondefective C3H/HeN mice. Nevertheless, the tumoricidal deficits of M phi diameter from the defective strains did not affect their suppressive capacity on Con A-induced lymphoproliferation, nor their ability to react to IFN-beta by decreasing suppressive activity. In fact, natural suppressive activity and IFN-beta-induced changes in the suppression of M phi diameter from C3H/HeJ, A/J, and P/J mice were highly comparable to those of C3H/HeN M phi diameter, thus stressing the dissociation between the mechanisms governing M phi diameter suppression and M phi diameter tumoricidal activity. Analysis of the modulation by MAF and IFN-beta of M phi diameter ability to release the oxygen metabolites O2- and H2O2, molecules possibly involved in the effector mechanism of both M phi diameter cytotoxicity and suppression, revealed a close correlation with the patterns of suppressive activity in both nondefective and defective strains. In contrast, no correlation between the production of oxygen-reactive species and M phi diameter tumoricidal activity was observed. The ability of MAF- and IFN-beta-treated M phi diameter to produce PGE, a molecule of major importance in M phi diameter-mediated suppression and possibly involved also in the regulation of M phi diameter tumoricidal activity, again paralleled M phi diameter suppressive capacity. Thus, the mechanisms controlling M phi diameter antitumor activity appeared to be clearly distinct from those involved in M phi diameter suppression.