bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibody-Induced Modulation of Leishmania Donovani Surface Membrane Antigens
Authors: Dwyer Dennis M. 
Published: December 2022

Abstract
The effects of specific antibodies on the surface membrane antigens of Leishmania donovani (strain 1S, clone 2D) amastigote and promastigote developmental stages was detected in vitro by using several direct and indirect immunofluorescence methods. Stage specific anti-L. donovani sera and sera from L. donovani-infected hamsters induced parasite surface membrane antigens to aggregate, move along the longitudinal cell axis, form polar cell caps, and subsequently disappear. No membrane fluorescence was observed in cells treated identically with normal sera. In amastigotes a single anterior cell pole cap was formed after antibody treatment. However, antibody-treated promastigotes showed tripartite membrane antigen capping consisting of a major anterior cell pole cap with minor caps at the posterior cell pole and flagellar tip regions. Loss of surface fluorescence from the two latter capped cell regions was frequently concurrent with the formation of extracellular fluorescent plasmanemes. The cell-capping process was antibody concentration, temperature, time, and energy dependent. No cell caps were formed at low temperature or in the presence of several metabolic inhibitors. Cell cap formation was also selectively inhibited by certain types of antibody-induced intercellular agglutination. Parasite membrane antigens removed by capping were regenerated and detectable at the cell surface only after a 3.5 to 4-hr period. Antibody-induced membrane antigen movement in L. donovani is apparently similar to phenomena observed with mammalian cells. Results of direct cross-staining and cross-absorption cell-capping experiments showed that the two parasite developmental forms shared some common or at least cross-reacting membrane antigens and that each form also possessed some unique stage-specific surface antigens. Cell-capping results with sera from L. donovani infected hamsters showed that this host produces some IgG which is directed specifically against certain parasite surface membrane antigens. The results suggest that host antibody-induced parasite membrane antigen modulation might have a role in the infectious process of this human pathogen.
The Genetics of Cell-Mediated Lympholysis
Authors: Long Mary Ann , Handwerger Barry S. , Amos D. Bernard , Yunis Edmond J. 
Published: December 2022

Abstract
The role of HLA antigens in the generation of cytotoxic cells in CML has been investigated. Cytotoxic effector cells were generated in MLC among HLA-A or HLA-A and HLA-B disparate, HLA-D identical siblings, and among HLA-A and HLA-B disparate, MLC identical (%RR ≦2 3.6) unrelated individuals. The data indicate that HLA-D differences and poliferative MLC responses as measured by 3H-thymidine incorporation are not requisite for the in vitro generation of cytotoxic cells and suggest the existence of a CML-S locus (loci) distinct from HLA-A, HLA-B and HLA-D. The degree of cytotoxicity generated in a proliferative versus a “nonproliferative” MLC was comparable.
In addition, these studies demonstrate that antigens other than the currently definable HLA-A, HLA-B, HLA-C, and HLA-D can serve as target determinants in cell-mediated lympholysis.
Analysis of Mononuclear Cell Surfaces with Fluoresceinated Staphylococcal Protein A Complexed with IgG Antibody or Heat-Aggregated γ-Globulin
Authors: Ades Edwin W. , Phillips Don J. , Shore Steven L. , Gordon David S. , LaVia Mariano F. , Black Charlotte M. , Reimer Charles B. 
Published: December 2022

Abstract
Fluorescein-conjugated staphylococcal protein A (SPA) was complexed with either: 1) heat-aggregated IgG, 2) B cell specific antibody, or 3) T cell specific antibody and then used for an immunofluorescent analysis of mononuclear cell surfaces. Cellular Fc receptors failed to recognize the Fc region of aggregated IgG that had been blocked by SPA. Moreover, fluoresceinated SPA that had been complexed either with anti-Fab (B-cell specific) or T cell-specific antisera prevented the nonspecific binding of these reagents to the IgG-Fc receptors on mononuclear cells, thereby permitting the latter to be properly identified as B or T lymphocytes. In addition, when unconjugated SPA was added to presensitized target cells in a test for antibody-dependent cell-mediated cytotoxicity, cytolysis was abrogated.
Effect of Vibrio Cholerae Neuraminidase on the Generation of Cell-Mediated Cytotoxicity in Vitro
Authors: Ferguson Ronald , Anderson Susan M. , Schmidtke Jon R. , Simmons Richard L. 
Published: December 2022

Abstract
Vibrio cholerae neuraminidase (VCN)(12.5 units/2 × 106 cells/ml) continuously present for a standard 5-day MLC will significantly (p &lt; 0.02) increase the cytotoxic activity generated by a given number of responding spleen cells without reducing the specificity. Heat-inactivated VCN produced no such augmentation. This augmented cytotoxicity could be reproduced by preincubating (1 hr) the responding spleen cells with VCN (25 units/2.5 × 106 cells/ml) before addition of stimulating spleen cells. Preincubating the stimulator spleen cells with VCN had no effect. VCN preincubation of target cells or presensitized effector cells produced no augmentation. The addition of soluble VCN to the killing assay also did not increase cytotoxicity. Thus, VCN acts only during the generation of specifically sensitized cytotoxic T cells. When the effect of VCN on MLC reactivity, cell recovery and total cytotoxicity (lytic units/106 cells) were compared, it became apparent that VCN increases the proliferation of responder cells after stimulation resulting in both an increased number of cells and also an increase in the proportion of specifically sensitized cytotoxic cells in the culture. VCN treatment of responder cell membrane apparently permits a more ready response to allogenic antigens in culture facilitating both increased proliferation and the increased development of specific cytotoxic killers.
Functional Characterization of Rat Mast Cell Arylsulfatase Activity
Authors: Orange Robert P. , Moore Elizabeth G. 
Published: December 2022

Abstract
Extracts of isolated rat peritoneal mast cells were demonstrated to contain appreciable quantities of arylsulfatase activity. The enzyme was inhibited by both phosphate and sulfate ions and demonstrated a pH optimum of 5.0. The enzyme was recovered in the eluate of DE-52 columns and appeared to have a m.w. of 150,000 on Sephadex G-200 gel filtration. These findings and the anomalous kinetic behavior of the enzyme suggest that at least part of the enzymatic activity is of the arylsulfatase IIA type. While spontaneous release of the enzyme was observed, challenge of isolated rat mast cells with a goat anti-rat IgE serum resulted in a significant increase in release of the enzyme. The arylsulfatase activity extracted from isolated rat mast cells demonstrated comparable activity in inactivating slow reacting substance of anaphylaxis (SRS-A) to that described for human eosinophil and lung arylsulfatase.
Cell-Mediated Destruction of Human Leukemic Cells by MHC Identical Lymphocytes: Requirement for a Proliferative Trigger in Vitro
Authors: Sondel Paul M. , O'Brien Carmeline , Porter Linda , Schlossman Stuart F. , Chess Leonard 
Published: December 2022

Abstract
These experiments have investigated cellular mechanisms involved in the generation of cellular immune responses to human acute leukemic blasts. Because normal human lymphocytes are not able to recognize immunologically, in vitro, lymphocytes from MHC identical siblings, the present studies have examined the in vitro proliferative and cytotoxic responses of normal lymphocytes to MHC identical AML and ALL blasts. In those cases where acute leukemic cells were unable to induce a proliferative response by MHC identical lymphocytes, the generation of effective anti-leukemic cytotoxicity required the addition of unrelated stimulating cells to the sensitization culture. In contrast, leukemic blasts that induced a proliferative response by MHC identical lymphocytes were also able to stimulate anti-leukemic cytotoxicity. This could be augmented by the addition of unrelated stimulating cells to the sensitization culture. The specificity of anti-leukemic cell cytotoxicity was demonstrated in all instances by simultaneous testing of putative killer cells on 51Cr leukemic blasts as well as 51Cr-labeled MHC identical phytohemagglutinin blasts or normal lymphocytes. Simultaneous sensitization to MHC identical leukemic blasts and unrelated stimulating lymphocytes did not invariably generate anti-leukemic cytotoxicity even when allogeneic cytotoxicity was observed; the absence of demonstrable suppressor activity in these nonreactive combinations suggested that some individuals may be specifically immuno-incompetent, and thereby unable to generate effective anti-leukemic CML.
Subpopulations of Chicken B Lymphocytes
Authors: Lifter John , Kincade Paul W. , Choi Yong Sung 
Published: December 2022

Abstract
Immunoglobulin-synthesizing cells from the spleen and bursa were fractionated by the 1 × G sedimentation velocity technique and characterized by their ability to synthesize immunoglobulin and by staining with fluorescent anti-light chain chain. Four subpopulations of immunoglobulin-synthesizing cells were identified. In the bursa, slowly sedimenting (S 2.3 mm/hr) and rapidly sedimenting (S greater than 3.5 mm/hr) subpopulations with surface immunoglobulin were present; in the spleen, a slowly sedimenting (S 2.3 mm/hr) subpopulation with surface immunoglobulin and plasma cells (S greater than 3.5 mm/hr) with large concentrations of intracellular immunoglobulin existed. The subpopulations differed most markedly in their ability to synthesize immunoglobulin (cpm Ig synthesized/106 Ig-positive cells); the rates of immunoglobulin synthesis were in the ratio 1:2:1:900. The slowly sedimenting B cells from the spleen and both subpopulations of B cells from the bursa released small amounts of immunoglobulin into the culture media, whereas, the plasma cells released immunoglobulin at a rate as much as 3700 times greater. Bursal B cells could be further distinguished from splenic B cells by a greater amount of DNA synthesis.
Hemolytic Plaque Inhibition: The Physical Chemical Limits on Its Use As an Affinity Assay
Authors: DeLisi Charles 
Published: December 2022

Abstract
An analysis of the fundamental physical chemical limits of hemolytic plaque inhibition as a method for obtaining thermodynamic and kinetic information is presented. It is shown that inhibition curve characteristics will be sensitive functions of reaction affinities only when the antibody inhibitor and antibody red blood cell reaction mechaisms are related in certain ways. It is further shown that conditions which are most sensitive to IgG affinity changes will generally not be the best for detecting changes in IgM affinity. The apparently conflicting reports on IgM maturation are completely explicable in terms of experimental requirements imposed by physical chemical characteristics of the reaction. Experiments in which maturation is observed are found to conform to the most sensitive conditions of the assay, whereas those in which it is not observed are found to conform to relatively insensitive conditions, and would therefore be capable of registering changes only when affinity shifts are large.
Chemical Treatment of Macrophages Increases Their Responsiveness to Migration Inhibitory Factor (MIF)
Authors: Remold Heinz G. 
Published: December 2022

Abstract
The response of guinea pig macrophages to migration inhibitory factor (MIF) is altered by several chemical treatments. Treatment of macrophages with the diazonium salt of sulfanilic acid (5 × 10-6 to 4 × 10-4 M) significantly increases the response of these cells to MIF. Treatment with acetic anhydride also augments the response of these cells to MIF. The latter finding suggests that alteration of amino, hydroxyl, or sulfhydryl groups is involved in this phenomenon. Treatment of macrophages with sodium periodate (2 × 10-5 to 10-3 M) which is known to oxidize cis-glycols and with hydroxylamine (2 × 10-5 to 2 × 10-3 M), which reacts with carbonyl groups also increases response to MIF. The following experiments suggest that the significant alteration occurs at the level of the cell surface. Incubation of macrophages with the diazonium salt of sulfanilic acid at 4°C, at which temperature pinocytosis is largely inhibited, is sufficient to increase the MIF response. The activity of the cytoplasmic enzyme aspartate aminotransferase, which in homogenates is susceptible to inactivation by low concentrations of the diazonium salt of sulfanilic acid, is not decreased when intact macrophages are incubated with high concentrations of the diazonium salt of sulfanilic acid. Cumulatively, these findings suggest that modification of different functional groups on the macrophage surface causes the same physiologic effect.
Passive Transfer of Systemic Tumor Immunity with Cells Generated in Vitro by a Secondary Immune Response to a Syngeneic Rat Gross Virus-Induced Lymphoma
Authors: Bernstein Irwin D. 
Published: December 2022

Abstract
Spleen cells taken from W/Fu rats 4 to 6 weeks after immunization with the syngeneic Gross virus-induced lymphoma, (C58NT)D cells, at a time when they lack detectable activity in a short-term 51Cr release assay, were previously shown to retain the capacity to generate cytotoxic activity upon reexposure to mitomycin C-treated lymphoma (C58NT)D cells in vitro. In the studies presented here, we evaluated whether in vitro sensitization of immune lymphoid cells before systemic transfer to a nonimmune recipient allows for more effective transfer of tumor immunity. The results show that the passive transfer of immune spleen cells after in vitro cocultivation with mitomycin-treated (C58NT)D cells allows for inhibition of growth of a subcutaneous inoculum of lymphoma cells. In contrast, spleen cells obtained 4 to 6 weeks after primary sensitization or after secondary in vivo sensitization did not effectively confer anti-tumor immunity. As few as 5 × 107 in vitro sensitized cells permitted complete inhibition of 106 (C58NT)D cells and also allowed for inhibition of the growth of 107 (C58NT)D-F cells, which was lethal to control animals. Immune cells sensitized with syngeneic thymocytes or normal spleen cells sensitized with (C58NT)D cells in vitro did not confer in vivo anti-tumor immunity. After systemic transfer of in vitro sensitized cells, delayed hypersensitivity occurred at the site of tumor inoculation and tumor growth was suppressed. Specificity of the passive immunity was shown by the failure to inhibit growth of a polyoma virus-induced sarcoma in rats which inhibited growth of the Gross virus-induced lymphoma cells. In vitro sensitized cells were more effective in the transfer of anti-tumor protection after 5 days, as compared to 2 days, of cocultivation with tumor. Results show that in vitro sensitized cells can effectively transfer systemic tumor immunity.
Reaginic Antibody Formation in the Mouse
Authors: Takatsu Kiyoshi , Ishizaka Kimishige 
Published: December 2022

Abstract
Attempts were made to increase the activity of suppressor cells in vitro. Antigen-specific suppressor cells were induced by i.v. injections of urea-denatured ovalbumin (UD-OA) into OA-primed mice. Nonadherent splenic lymphocytes from the UD-OA-treated mice were incubated at 37°C for 24 hr with either OA or OA-bearing macrophages and lymphocytes harvested from the culture were examined for the ability to suppress primary anti-hapten antibody response of nonirradiated mice to DNP-OA. The results showed that the suppressive activity of the lymphocytes increased after culture of the cells with OA or OA-bearing macrophages. Similar results were obtained when nylon column-purified T cell-rich fraction of the lymphocytes were similarly cultured. The suppressive activity was associated with ϑ-bearing lymphocytes and was specific for OA. Suppressor cells were not induced by the culture of OA-primed lymphocytes with OA. The helper function of splenic lymphocytes from both UD-OA-treated mice and OA-primed mice was enhanced by the culture of the cells with OA-bearing macrophages but not by culture with OA in the absence of macrophages.
Reversal of SV40 Tumor-Mediated Suppression of Spleen Cell Cytotoxicity by Antibody
Authors: Prather Suzanne O. , Lausch Robert N. 
Published: December 2022

Abstract
Spleen cells obtained from hamsters bearing PARA-7 tumors greater than 1.0 cm were not reactive in microcytotoxicity assays unless preincubated overnight. The events occurring during in vitro incubation which lead to reversal of tumor-mediated suppression of cellular immunity were investigated. After 24 hr of incubation, supernatants overlying spleen cells from tumor-bearing hosts contained a factor which blocked cytotoxicity of simian virus 40 (SV40)3-sensitized spleen cells at the PARA-7 target cell level but not at the effector cell level. The preparations did not mediate antibody-dependent cellular cytotoxicity (ADCC). Opposite results were obtained in assays of culture medium overlying spleen cells from hosts with a tumor burden less than 0.1 cm. Although ADCC activity was present, no significant blocking was detectable.
Treatment of inactive spleen cells with anti-hamster γ-globulin in the presence of complement (anti-HGG + C) prevented activation and formation of blocking factor but did not impair the cytotoxic activity of already activated cells. Addition of SV40 antiserum to anti-HGG + C-treated cells led to effector cell activation, whereas heterologous virus-immune sera did not. Control studies established that the antibody-mediated recovery of cytotoxicity was not due to arming. Further studies showed that PARA-7 tumor antigen extract blocked at the effector cell level, not at the target cell level. Addition of PARA-7 extract to spleen cell supernatants mediating ADCC resulted in formation of a factor which blocked at the target cell level but not at the effector cell level.
These data are compatible with the following interpretation. Spleen cell unresponsiveness is due to antigen blockade. Recovery of cytotoxicity occurs because antibody synthesized during the incubation period promotes elution of antigen from the effector cell surface. Thus, activation is accompanied by the generation of tumor antigen-antibody complexes.
Inhibition of the Mitogenic Response to Lipopolysaccharide (LPS) in Mouse Spleen Cells by Polymyxin B
Authors: Jacobs Diane M. , Morrison David C. 
Published: December 2022

Abstract
The addition of low doses of the cationic polypeptide antibiotic, polymyxin B (PB), to cultures of mouse spleen cells inhibits lipopolysaccharide-(LPS) induced DNA synthesis but not that stimulated by PPD, PHA, or Con A. Inhibition is stoichiometric; the mitogenic response is suppressed by 50% at a weight ratio of PB:LPS of 0.055 to 1. Furthermore, PB-LPS complexes have a much reduced mitogenic capacity. These complexes inhibit the mitogenic response of spleen cells to unmodified LPS but not to PPD, Con A, or PHA. The inhibitory activity of PB is less effective when added after LPS is mixed with responding cells, achieving 50% inhibition when addition is made at 4 to 6 hr. Time course experiments indicate that partial inhibition is a reflection of a lower rate of DNA synthesis. Thus, PB inhibition of LPS mitogenesis apparently occurs as a result of formation of PB-LPS complexes with reduced mitogenic capacity. Specific inhibition by the complexes of mitogenesis induced by native LPS suggests that the inactive complex may bind to B cells but is unable to trigger them.
Amyloid-Related Serum Protein SAA from Three Animal Species: Comparison with Human SAA
Authors: Anders Robin F. , Natvig Jacob B. , Sletten Knut , Husby Gunnar , Nordstoga Knut 
Published: December 2022

Abstract
The amyloid-related serum protein SAA has been isolated by gel filtration in 10% formic acid from three animal species: mink, mouse, and rabbit. Sera used in the isolation procedure were obtained from animals in which high concentrations of SAA had been induced by treatment with LPS.
The isolated SAA proteins had a subunit size similar to that of human SAA, with m.w. values ranging from 10,000 to 11,700 (estimated by gel filtration in 6 M guanidine-HCl) or 12,400 to 15,000 (estimated by SDS-PAGE). The m.w. studies and amino acid sequence data indicated that SAA and the amyloid fibril protein AA in the mouse, and probably also the mink, are related in the same way as in man, the two proteins having common NH2-terminal amino acid sequences and SAA being extended by 20 to 40 residues at the COOH-terminal end of the molecule.
The Active E-Rosette Test: A Sensitive in Vitro Correlate for Human Delayed-Type Hypersensitivity
Authors: Felsburg Peter J. , Edelman Robert 
Published: December 2022

Abstract
The “active” rosette test was adapted as an in vitro assay and correlated with human delayed cutaneous hypersensitivity (DCH) to two microbial antigens. Peripheral lymphocytes were purified from donors known to be responders or nonresponders to PPD-tuberculin or tularemia on the basis of prior DCH reactions. Skin test antigen, incubated with lymphocytes from antigen-sensitive donors, produced a significant increase (+2 S.D.) in the ability of the lymphocytes to form active rosette-forming cells (A-RFC) when compared to lymphocytes cultured without antigen. Skin test antigen incubated with lymphocytes from nonsensitive donors produced no increase in their A-RFC. The optimal dose of each antigen was approximately 100 ng/ml. The percentage of A-RFC rose to maximum levels between 3 and 4 hr after the addition of antigen to the lymphocytes incubated at 37°C. The assay appears to be specific for the antigen to which the individual demonstrates DCH. This assay may provide a new in vitro method for investigating mechanisms of cell-mediated immunity and a rapid diagnostic test for sensitization to microbial antigens.
Structural Differences between Parent and Mutant H-2K Glycoproteins from Two H-2K Gene Mutants: B6.C-H-2ba (Hzl) and B6-H-2bd (M505)
Authors: Brown J. Lynne , Nathenson Stanley G. 
Published: December 2022

Abstract
The H-2K glycoproteins from two mouse mutants B6.C-H-2ba (Hzl) and B6-H-2bd (M505) were isolated, and by tryptic peptide mapping techniques, were compared with each other and with the H-2K glycoprotein from the parent strain C57BL/6 (H-2b). The elution profile of the acid-soluble tryptic peptides from the H-2Kba glycoprotein showed that at least two to three arginine-labeled peptides and one lysine-labeled peptide were different from the H-2Kb product of the parent. These peptides were distinct from the soluble peptides which constitute the difference which was found between the H-2K products of H-2bd and the H-2b parent strains. The comparative peptide maps thus demonstrate small but significant primary structural differences among the H-2Kba, H-2Kbd, and H-2Kb glycoproteins. The findings are in agreement with the suggestion that alterations in the H-2K products from these two mutants are sufficient to permit their cells to stimulate each other and the parent cells in the mixed lymphocyte reaction (MLR) and to serve as target cells for the cell-mediated lymphocytotoxicity (CML) test. Because there is a significant reactivity in MLR and CML between H-2Kb, H-2Kba and H-2Kbd cells whereas there is no serologic reactivity, our findings are consistent with the notion there is a separation of the site(s) on the H-2 molecule having serologic reactivity and the site(s) involved in the MLR and CML reactivities.