bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterologous Antiserum to Rat Lymphohemopoietic Precursor Cells
Authors: Goldschneider Irving 
Published: December 2022

Abstract
Lymphohemopoietic precursor cells in rat bone marrow are members of a subset of lymphocyte-like cells that bears the bone marrow lymphocyte antigen (BMLA) and that lacks antigens present on peripheral T and B cells. This was demonstrated by two experimental approaches. In the first, bone marrow cells with the potential to form hemopoietic colonies in spleen (CFU-S), to repopulate lymphoid tissues and blood, and to rescue lethally irradiated recipients were enriched approximately 10-fold by a fractionation procedure designed to isolate a “null” population of bone marrow lymphocytes. In the second approach, the lymphohemopoietic precursor cell activity in bone marrow was completely abrogated by opsonization with rabbit antiserum (ALSBM) raised against this “null” population of bone marrow cells. Precursor cell activity was not affected by treatment with antiserum to T and B cells. Quantitative crossabsorption studies showed that the antigen detected by ALSBM on lymphohemopoietic precursor cells had the same cellular distribution as did the previously described bone marrow lymphocyte antigen. It is likely that this antigen is present both on pluripotent stem cells and on committed progenitors of the myelocytic, erythrocytic and lymphocytic series.
Antigen Handling by Guinea Pig Macrophages: Further Evidence for the Sequestration of Antigen Relevant for Activation of Primed T Lymphocytes
Authors: Ellner Jerrold J. , Lipsky Peter E. , Rosenthal Alan S. 
Published: December 2022

Abstract
Guinea pig macrophages can take up sufficient 2,4 dinitrophenyl guinea pig albumin during a brief in vitro exposure at 37°C to trigger proliferation and lymphokine production with primed T lymphocytes on subsequent co-culture. Treatment of such antigen-bearing macrophages with trypsin, a procedure which removes surface antigen, does not alter the ability of such macrophage to initiate the release of migration inhibition factor from sensitized T lymphocytes. In addition, formation of antigen-specific rosettes between primed T cells and antigen-bearing macrophages is not blocked by high concentrations of antibody directed against the antigen mediating this interaction. Similarly, primed T lymphocyte DNA synthesis induced by antigen-bearing macrophages is not inhibited by specific antibody to that antigen. These data support the conclusion that the fraction of macrophage-associated antigen which is relevant to T lymphocyte activation does not reside on the macrophage surface but rather remains in a restricted compartment from which it is accessible to the T cell but unavailable to either blockade by specific antibody or removal by proteolytic enzymes.
Increased Responsiveness to Macrophage-Activating Factor (MAF) after Alteration of Macrophage Membranes
Authors: Piessens Willy F. , Remold Heinz G. , David John R. 
Published: December 2022

Abstract
Guinea pig macrophages pretreated with the esterase inhibitor, antithrombin III (AT III) show increased responsiveness to macrophage-activating factor (MAF) as demonstrated by their enhanced cytotoxicity for tumor cells. Other proteins that are not esterase inhibitors did not enhance the effect of MAF on the macrophage.
Enhancement of MAF activity was also obtained when macrophages were preincubated with the cell surface reactant, diazotized sulfanilic acid (DSA).
These studies indicate that the effect of MAF can be enhanced by chemical modifications of the macrophage membrane. They also provide further evidence to support the hypothesis that an esterase on the macrophage membrane modulates this cell's responsiveness to lymphocyte mediators.
Ag-B-Linked Analogue of Ia Antigens in the Rat
Authors: Shinohara Nobukata , Cullen Susan E. , Sachs David H. 
Published: December 2022

Abstract
The reactions of Lewis rat lymphocyte membrane antigens with two alloantisera, BN anti-Lewis and BN anti-Fischer have been studied. Three lines of evidence indicated that these antisera reacted with cell surface antigens homologous to Ia antigens of the mouse. 1) After absorption with Lewis platelets, the antisera killed only 40 to 50% of Lewis spleen cells. The majority of such cells were shown to be Ig-positive B cells by the examination of reaction patterns on lymphocytes after separation on nylon wool into T cell- and B cell-enriched subpopulations. 2) SDS-PAGE analysis of solubilized Lewis spleen cell antigens precipitated with these antisera revealed that the platelet-absorbed antisera reacted with molecules comparable in size to mouse Ia antigens (mw ≡ 35,000 and 28,000). The unabsorbed sera reacted with these molecules and with additional molecules corresponding in size to mouse K and D antigens (m.w. ≡ 45,000). 3) Neither of these antisera killed significant numbers of spleen cells from the partially congenic strain F.BN (seventh backcross homozygotes), a Fischer rat to which the Ag-B.3 allele is being transferred by repetitive backcrossing, indicating that the genes coding for these Ia-like antigens in the rat are linked to the Ag-B locus.
Sites of “Spontaneous” Degradation of IgD
Authors: Goyert Sanna M. , Hugli Tony E. , Spiegelberg Hans L. 
Published: December 2022

Abstract
When 10 IgD myeloma proteins were examined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE), the δ-chains of each protein showed multiple banding; the average extrapolated m.w. for the two major bands was 63,900 ± 735 and 60,550 ± 675 daltons. When compared to δ-chains, only ε-chains and not σ-, α- or µ-chains showed a multiple banding pattern. Double reciprocal plots of the observed m.w. versus varying acrylamide gel concentrations demonstrated that of all the Ig heavy chains δ-chain mobility was most variable. Digestion of δ-chains with yeast carboxypeptidase caused an initial release of methionine and proline, followed by leucine, tyrosine, valine, and serine. Carboxypeptidase A did not release any amino acids, whereas carboxypeptidase B released fractional molar quantities of both lysine and arginine. Therefore, the native δ-chain probably has a Pro-Met-COOH carboxy-terminal sequence analogous to the Pro-Gly-COOH sequence of δ-chains. A portion of the δ-chains may have undergone degradation near the COOH-terminus by an enzyme with tryptic like specificity, thus explaining the nominal release of basic residues by CPB as well as the multiple forms of the δ-chain seen by SDS-PAGE analysis. Tryptic Fc but not Fab or Fd fragments of IgD showed multiple banding by SDS-PAGE analysis which provides further evidence that the COOH-terminal region of the δ-chain is responsible for the apparent heterogeneity.
The NH2-terminal sequence of Fc fragments isolated from IgD that had undergone “spontaneous” fragmentation during isolation was analyzed. The fragments formed by serum enzymes showed multiple sequences in contrast to Fc fragments generated by trypsin which gave a singular NH2-terminal sequence. Three cleavage sites were deduced for lysyl and arginyl residues 6, 8 and 12 residues NH2-terminal to the common half-cystine residue which participates in the inter-heavy chain disulfide bond. These data demonstrate that the δ-chain is highly susceptible to degradation both near the COOH-terminus and in the inter-Fd-Fc region by plasma enzymes of trypsin-like specificity.
Niridazole Suppression of Experimental Allergic Encephalomyelitis in Lewis Rats
Authors: Paterson Philip Y. , Harvey Johanne M. , Webster Leslie T. 
Published: December 2022

Abstract
Administration of niridazole to Lewis rats beginning 2 days before sensitization with guinea pig spinal cord in combination with immunologic adjuvants exerted a dose related suppressive influence on development of experimental allergic encephalomyelitis (EAE). A daily dose of 75 mg/kg completely prevented clinical neurologic signs as well as markedly suppressed occurrence of immunohistopathologic manifestations of this autoimmune disease. A higher daily dose level of niridazole, i.e., 100 mg/k, also inhibited EAE but was associated with neurotoxic manifestations.
The Elimination of Herpes Simplex Plaques by Antibody and the Emergence of Resistant Strains
Authors: Pavan Peter Reed , Ennis Francis A. 
Published: December 2022

Abstract
Established type 1 HSV plaques were eliminated by antibody. Antibody had to remain in contact with infected cells for several days to have a maximum effect. It did not prevent the production of viral induced antigens in a cell when applied after the cell was infected but did prevent the transmission of infection to contiguous cells. Strains which were resistant to elimination by antibody formed syncytia, did not grow to significantly higher titers than nonresistant strains, and were as easily neutralized by antiserum as nonresistant strains.
Mitogenic Receptors on Human Peripheral Blood Lymphocytes: The Interaction of Phaseolus Vulgaris Erythroagglutinating Phytohemagglutinin and Anti-Thymocyte Globulin on the Human Peripheral Blood Lymphocyte Membrane
Authors: Kelly James P. , Wedner H. James , Parker Charles W. 
Published: December 2022

Abstract
A horse anti-human thymocyte antibody (ATG) obtained from the Upjohn Company was shown to stimulate DNA synthesis in human lymphocytes with a time course and magnitude of radioactive thymidine uptake comparable to that seen with phytohemagglutinin (E-PHA) and concanavalin A (Con A). Low mitogenic or nonmitogenic concentrations of intact ATG or its Fab fragments inhibited E-PHA-induced mitogenesis, whereas the response to Con A was unaffected. Competitive binding studies with ATG and E-PHA revealed mutual inhibition of binding to lymphocytes suggesting that E-PHA and the ATG share a common receptor site on the cell surface. ATG binding was unaffected by Con A. From the analysis of the binding data and the inhibition of mitogenesis, it appears that at least part of the E-PHA response in human lymphocytes involves receptors that are not acted on by Con A.
Antibody-Dependent Eosinophil-Mediated Damage to 51Cr-Labeled Schistosomula of Schistosoma Mansoni: Mediation by IgG, and Inhibition by Antigen-Antibody Complexes
Authors: Butterworth Anthony E. , Remold Heinz G. , Houba Vaclav , David John R. , Franks David , David Peter H. , Sturrock Robert F. 
Published: December 2022

Abstract
The properties of the antibodies responsible for complement-independent, eosinophil-mediated damage to schistosomula have been characterized in serum samples from Schistosoma mansoni-infected baboons and human patients. The antibody is opsonic for the target larvae, but is not detectably cytophilic. It is associated with IgG-rich fractions after DEAE-cellulose chromatography, and is removed by anti-IgG immunoadsorbents. In studies on the specificity of the antibody, it was found that activity was also removed by absorption with whole schistosomula, but not with an insoluble adult worm membrane preparation. In this preparation, however, membrane antigens may have been masked; and immunofluorescence studies showed that absorption with schistosomula was associated with loss of activity against the adult worm membrane, indicating a cross-reactivity between schistosomular and adult worm antigens.
A finding that activity was also lost after incubation of sera with soluble adult worm antigens was possibly attributable to the formation of immune complexes which blocked effector cell activity. In further studies, it was shown that preincubation of effector cells with exogenous immune complexes resulted in a loss of cytotoxic activity, supporting the hypothesis that Fc receptors are involved in the initial interaction between eosinophils and antibody-coated larvae. The blockade of eosinophil-enriched effector cells by immune complexes was not reversed by washing and subsequent overnight culture before assay. A possible relationship between circulating immune complexes and the relative inactivity of cells from patients with schistosomiasis and eosinophilia is discussed.
Characterization and Specificity of Murine Anti-Tumor Cytotoxic Effector Cells within an Ascitic Tumor
Authors: Biddison William E. , Palmer Jon C. , Alexander Michael A. , Cowan Elliot P. , Manson Lionel A. 
Published: December 2022

Abstract
The anti-tumor immune reactivity of cells which are contained within a progressively growing ascitic tumor has been analyzed by studying the cell-mediated response of DBA/2 mice to the syngeneic mastocytoma P815Y. Peritoneal cells (P.C.) which were harvested from these P815Y tumor-bearing hosts were fractionated by velocity sedimentation at unit gravity. Cell-mediated cytotoxicity (CMC) of fractionated and unfractionated cells was measured by a 4-hr51Cr-release assay. The cell separation procedure revealed significant levels of CMC to P815Y in P.C. populations at 8 to 16 days following i.p. inoculation of 1 × 103 viable P815Y cells. The tumor-bearer P.C. which mediated CMC against P815Y were generally confined to P.C. populations that sedimented between 2 and 6 mm/hr. The cytolytic activity against P815Y mediated by tumor-bearer P.C. was sensitive to treatment with an anti-Thy-1.2 preparation and complement, but not to treatment with anti-immunoglobulin serum and complement. CMC against P815Y by tumorbearer P.C. was not inhibited by the presence of heat-aggregated human γ-globulin. In addition, it was shown that the cytolytic activity of tumor-bearer P.C. against P815Y was not mediated by “natural” killer cells, since the cytolytic activity was not labile at 37°C in culture. These results indicate that T lymphocytes which are cytotoxic for tumor cells in vitro can be found within a growing ascitic tumor.
Analysis of the specificity of DBA/2 anti-P815Y cytotoxic T lymphocytes (CTL) demonstrated that these effector cells could lyse three of four DBA/2 tumor lines and four of four C57BL/6 tumor lines which were tested. Cytolysis of two strain A tumors and Con A- and LPS-induced DBA/2 or C57BL/6 lymphoblasts was not observed. No correlation was found between the surface expression of the gp69/71 or p30 components of murine leukemia virus and the susceptibility of tumor cells to lysis by these CTL. These results indicate the T cell killing directed against shared antigenic determinants on P815Y and other tumor cells is not H-2 restricted and that gp69/71 and p30 are not the target specificities recognized by DBA/2 anti-P815Y CTL.
The Formation of Stable E-Rosettes by Human T Lymphocytes Activated by Phytohemagglutinin
Authors: Katoh Arthur K. , Charoensiri Surin 
Published: December 2022

Abstract
Sheep red blood cells (SRBC), when incubated with human peripheral blood lymphocytes (PBL),2 form rosettes (1). The lymphocytes that participate in rosette formation by adhering to SRBC are generally believed to be T lymphocytes (2). These rosettes have been shown to disintegrate rapidly if incubation of the reaction is carried out at 37°C (3). In striking contrast, however, is the behavior of rosettes formed by human thymus cells, which are highly stable and do not disintegrate even after prolonged incubation at 37°C (4).
Galili and Schlesinger (5) reported that human PBL, when treated by allogeneic stimuli in mixed lymphocyte cultures, were resistant to the degradative effects of 37°C incubation on the rosettes formed with SRBC. They suggested that the T lymphocytes were activated in mixed lymphocyte cultures to form stable E-rosettes.
The Role of Activated Accessory Cells in Preventing Immunosuppression by Hydrocortisone
Authors: Mishell Robert I. , Lucas Alexander , Mishell Barbara B. 
Published: December 2022

Abstract
The generation of humoral immunity in vitro by normal and antigen-primed mouse spleen cells was suppressed by in vitro treatment with hydrocortisone. Functions of normal and antigen-activated helper T lymphocytes and of accessory cells were inhibited by the corticosteroids. Spleen cells cultured overnight in medium containing fetal bovine serum became highly resistant to the effects of hydrocortisone. Similar resistance was found to occur when spleen cells were cultured with accessory cells that previously had been activated with bacterial lipopolysaccharide. These studies show that immunologically nonspecific processes significantly alter the effects of the steroids on specific immune responses and suggest that accessory cell products modulate T cells in ways which differ from antigen induction.
The Binding of Antibodies to the Solubilized and Membrane-Integrated Mouse and Rat Receptor for IgE
Authors: Isersky Chaviva , Mendoza Guillermo R. , Metzger Henry 
Published: December 2022

Abstract
Rabbit antiserum to rat basophilic leukemia cells (anti-RBL) inhibited the binding of 125I-IgE to and caused agglutination of RBL and mouse mastocytoma cells. Immunoglobulin G, Fab′, and Fab derived from this antiserum inhibited binding of 125I-IgE to whole rat and mouse tumor cells, normal rat peritoneal mast cells, and to detergent-solubilized receptors from either cell line. The inhibition was less efficient with receptors from the mouse mastocytoma and no inhibition of binding of 125I-IgE to normal mouse peritoneal mast cells was observed. The degree of inhibition of IgE binding to whole cells and solubilized rat and mouse receptors was inversely proportional to the time of incubation with and concentration of 125I-IgE. In a double immune precipitation system, anti-RBL reacted with detergent-solubilized receptors and IgE — receptor complexes derived from either mouse or rat cells. However, although nearly 100% of the free rat receptors could be precipitated no more than 70% of free mouse receptor were maximally precipitated. The efficiency of precipitation of detergent-solubilized free receptors, and the maximal precipitation of receptor — IgE complexes by anti-RBL were decreased when the detergent was above the critical micelle concentration. However, neither the precipitation of receptor — IgE complexes by anti-IgE, nor the binding of 125I-IgE to the free receptor was significantly affected under the same conditions.
The results suggest that the anti-RBL contains antibodies to at least two discrete determinants on the receptor. One determinant (or group of determinants) is sufficiently close to the combining site for IgE to interfere with IgE binding and in turn is blocked from binding by the presence of IgE. The second is distal from the first, is exposed at low detergent concentration even in the presence of IgE, but is blocked when the receptor interacts with larger amounts of detergent. Taken together with other data these findings suggest that the receptor is substantially embedded in the surface membrane.
Conditions Affecting the Immunosuppressive Properties of Human α-Fetoprotein
Authors: Goeken Nancy E. , Thompson John S. 
Published: December 2022

Abstract
The hypothesis that α-fetoprotein (AFP) is immunosuppressive in vitro was tested with immunoabsorbent purified human cord AFP in human lymphocyte cultures. Albumins were purified identically from cord plasma and pooled adult plasma. No preparations were suppressive in phytohemagglutinin-stimulated cultures. Both AFP and human cord albumin (HCA) produced 50% suppression of allogeneic lymphocyte cultures at 50 to 100 µg/ml final concentrations, whereas adult and commercial albumins were not suppressive. When AFP was eluted from the immunoabsorbent column in 0.15 M NaCl rather than the conventional 0.5 M NaCl, activity was greatly diminished or lost, but could be restored by dialysis against 0.5 M Kcl. Previously, inactive lots of HCA also demonstrated the same phenomenon. It appears, therefore, that the immunosuppressive activity of AFP (and albumin) may depend both on its source and the procedure by which it is isolated. Whether analogous conditions occur in vivo is unknown at this time.
Suppression of Lymphoproliferation by High Concentrations of Normal Human Mononuclear Leukocytes
Authors: Laughter Arline H. , Twomey Jeremiah J. 
Published: December 2022

Abstract
Mononuclear leukocytes (MNL) include cells that suppress lymphoproliferation in unstimulated and antigenstimulated cultures. Suppression is demonstrated by increasing the concentration of cells added to cultures and does not require preactivation of suppressor cells. Suppression of 3H-thymidine incorporation occurred if the high concentrations of MNL were added to cultures before the proliferative responses commenced. This suppressive effect of high cell concentration upon 3H-thymidine incorporation is removed by depleting MNL present in high numbers of cells that adhere to foreign surfaces or by preincubating these cells with cycloheximide, puromycin, or pactamycin. The suppressor cell, which only functions when present in a viable state, is radioresistant, adheres to foreign surfaces, remains active through 5 days in culture, and equates with the presence of a cell that is rich in cytoplasmic esterase. The suppressor cell may be of the monocyte series and did not appear to belong to either the T or the B lymphocyte series. This study provides additional evidence that normal immune reactivity in man is under regulatory control. The suppressor mechanism identified herein with normal human MNL is probably related to a similar type of suppression (but at a much lower cell concentration) that has been described with Hodgkin's disease and solid tumors.
Genetic Polymorphism of the Sixth Component of Complement (C6) in the Rhesus Monkey
Authors: Hall Joseph E. , Alper Chester A. 
Published: December 2022

Abstract
With isoelectric focusing, the complement protein C6 has been shown to be genetically polymorphic in the rhesus monkey. Three codominant alleles of a single autosomal locus, Rh C6, have been recognized: C6A, C6B, and C6R, with gene frequencies of 0.592, 0.354, and 0.053 in a random rhesus monkey population. Hardy-Weinberg analysis of the phenotypic frequencies in this population yielded observed values very close to those expected. Both natural mating between individuals carrying the various alleles and artificial combinations of sera of the different C6 types demonstrate patterns consistent with this model. Analysis of several families of monkeys confirmed the Mendelian autosomal codominant inheritance with numbers of offspring very close to expected values and no offspring types inconsistent with the mating pair types.
Identification of RNA as a Complement Inhibitory Component in an Extract of Ehrlich Ascites Tumor Cells
Authors: Renk Clifford M. , Hoffmann Edward M. 
Published: December 2022

Abstract
A factor capable of inhibiting complement was obtained from intact Ehrlich ascites tumor cells by mild extraction with phosphate-buffered saline (PBS). The inhibitor caused a decrease in extent of lysis of EAC with a concomitant extension of Tmax. EA, EAC1̄, EAC4 and were all less susceptible to complement-mediated lysis after treatment with the tumor cell extract. Partial purification of a complement inhibitor was accomplished. The inhibitor was rich in RNA and its activity was totally destroyed by RNAase but not DNAase. RNA from mouse tissues, yeast, and Escherichia coli also inhibited complement hemolytic activity. The partially purified material only inhibited lysis of EAC1̄ and EAC. Slow inhibition of fluid phase C1̄ was also demonstrated. In addition, RNA-rich partially purified tumor cell extract was capable of precipitating with purified human C1q.