bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tumor-associated macrophages of mouse mammary tumors. I. Differential cytotoxicity of macrophages from metastatic and nonmetastatic tumors.
Authors: Loveless S E , Heppner G H 
Published: December 2022

Abstract
Macrophages were isolated from a series of transplanted mouse mammary tumors, originally derived from a single spontaneously arising tumor, to determine whether macrophage content or function correlated with any of a wide range of tumor properties. None of the tumor cell lines differed significantly in susceptibility to killing by MVE-2-activated peritoneal macrophages (cytotoxicity ranged from 40 to 63%). No significant differences were observed in macrophage content among the five tumor lines, nor was there any correlation between macrophage content and tumor weight, time since transplantation, or ability to metastasize. A significant association was observed, however, between a tumor's ability to metastasize to lung spontaneously and the tumoricidal activity of that tumor's infiltrating macrophages. Significant tumoricidal activity was seen when macrophages isolated from every metastatic tumor studied were used, whereas macrophage-mediated tumoricidal activity was observed in only 35% (6 of 17) of nonmetastatic tumors. Macrophage cytotoxicity was associated with spontaneous metastasis and not with lung colony formation per se.
The use of acetylated cytochrome c in detecting superoxide anion production in rabbit alveolar macrophages.
Authors: Nasrallah V N , Shirley P S , Myrvik Q , Waite M 
Published: December 2022

Abstract
Polymorphonuclear phagocytes have been shown to undergo marked alteration in oxidative metabolism during phagocytosis. These alterations, collectively known as the "respiratory burst", include increased glucose oxidation through the hexose monophosphate shunt (1), increased oxygen consumption (1), and increased superoxide (O-2)3 (2) and H2O2 production (3). Similar metabolic events have also been shown to occur in the rabbit alveolar macrophage (AM). There is consistent evidence that the macrophage undergoes increased oxygen consumption (4-6) and hexose monophosphate shunt activity (4-9) upon phagocytosis. There are conflicting data, however, concerning the ability of the macrophage to produce O-2. Some studies suggest that macrophages are incapable of producing measurable amounts of O-2 upon phagocytosis (7, 10-12). Other studies, however, suggest that macrophages are indeed capable of producing substantial amounts of O-2 during phagocytosis (8, 13-15). This study was designed to resolve the discrepancies in the literature concerning O-2 production in macrophages.
Thymocyte and macrophage interactions: separation of murine thymocyte subsets and enrichment of syngeneic cell-responding thymocytes by adsorption to macrophage monolayers.
Authors: Wu S , Thomas D W 
Published: December 2022

Abstract
The spontaneous binding of murine thymocytes to macrophage monolayers was employed to separate thymocytes into macrophage-unbound and -bound subsets, and the functional reactivities of these two subpopulations were examined. Macrophage-unbound thymocytes were found to be enriched in functional subsets reactive to semi-allogeneic and allogeneic stimulating spleen cells by proliferation in mixed leukocyte culture (MLC). Furthermore, macrophage-unbound thymocytes were frequently found to respond to syngeneic spleen cells. This syngeneic proliferative response showed both memory and specificity upon subsequent restimulation and thus seems to represent a syngeneic mixed leukocyte reaction (SMLR). Syngeneic responding thymocytes were also found to produce interleukin 2 when cultured with syngeneic but not allogeneic stimulator cells. In contrast, macrophage-bound thymocytes showed greatly reduced proliferative responses to allogeneic stimulators and no responses to syngeneic stimulators. The macrophage-bound thymocyte subset was not enriched in detectable suppressive activity; proliferative responses of macrophage-unbound thymocytes to either allogeneic or syngeneic cells were neither suppressed nor enhanced when macrophage-unbound thymocytes were added to the cultures. Thus, the macrophage-unbound subset seems to be enriched in functionally mature thymocytes and the macrophage-bound subset appears to be enriched in functionally immature thymocytes. This functional separation of thymocytes by macrophage adherence also correlated well with thymocyte subpopulations separated by bovine serum albumin density gradients; the low density mature thymocytes showed enhanced responses to both allogeneic and syngeneic stimulators, whereas the high density immature cells were unresponsive. This correlation was supported further by binding studies in which T cell tumor lines derived from C57BL/6 mice were used. ERLD tumor cells, which are similar to cortical immature thymocytes in both enzymatic and surface antigenic markers, were found to bind readily to macrophages, whereas both EL-4 and E male G2 tumor cells, with characteristics of mature thymocytes, bound to macrophages poorly. The binding of thymocytes and ERLD tumor cells to macrophages was not genetically restricted. We speculate that thymocyte binding to macrophages may play a critical role during the functional maturation of thymocytes.
Monocyte-independent stimulation of human B lymphocytes by phorbol myristate acetate.
Authors: Bertoglio J H 
Published: December 2022

Abstract
Phorbol myristate acetate (PMA) induces a low level of proliferation in purified human B lymphocytes when added in nanomolar concentrations to the culture medium. Much higher levels of thymidine incorporation, however, are obtained in the presence of other B cell stimuli such as anti-IgM antibodies or Staphylococcus aureus Cowan Strain 1 (SAC). The peak activity of PMA was observed on day 3 of B cell cultures containing either anti-IgM or SAC. The rigorous depletion of monocytes as well as add-back experiments indicate that the effect of PMA on anti-IgM-stimulated B cells is not mediated by the stimulation of accessory cells. Thus, PMA acts as a very potent mitogenic agent for human B cells under culture conditions that are commonly used to assess B cell growth factor activity.
Suppressor T cell activation by human leukocyte interferon.
Authors: Schnaper H W , Aune T M , Pierce C W 
Published: December 2022

Abstract
Murine fibroblast interferon (IFN beta) activates murine suppressor T lymphocytes in vitro, which suppress plaque-forming cell responses by spleen cells. Suppression of human in vitro immune responses by IFN was investigated to determine whether human IFN also activates suppressor T cells. Human leukocyte IFN (IFN alpha) suppressed pokeweed mitogen-induced polyclonal immunoglobulin production by human peripheral blood mononuclear cells (PBMC) by 80 to 90% at doses of 200 to 350 U/ml. Responses by IFN alpha-treated PBMC were suppressed in a dose-dependent manner; control cultures had maximal responses on day 7. PBMC incubated with 10,000 U/ml of IFN alpha contained activated suppressor cells that decreased pokeweed mitogen-stimulated, polyclonal immunoglobulin production by autologous cells by 70 to 80%. Suppression mediated by these cells was prevented by catalase, ascorbic acid, and 2-mercaptoethanol (2-ME). In murine systems, these reagents interfere with expression of suppressor T cell activity by preventing activation of soluble immune response suppressor. Selection procedures with monoclonal antibodies identified the suppressor cell as an OKT8+ (suppressor/cytotoxic) T lymphocyte. Selected OKT8+ cells required less IFN alpha (1000 U/ml) for activation and were effective in smaller numbers than unfractionated activated PBMC. IFN alpha-activated suppressor cells also inhibited proliferation in mixed lymphocyte and mitogen-stimulated PBMC cultures; again, catalase and 2-ME blocked suppression. These results indicate that IFN alpha activates suppressor T cells in human PBMC cultures; the ability of catalase, 2-ME, and ascorbic acid to block suppression suggests that these suppressor T cells have certain similarities to IFN beta or to concanavalin A-activated murine suppressor T cells.
Fate and mechanism of clearance of PSAP, a schistosome antigen, in schistosomiasis.
Authors: Nash T 
Published: December 2022

Abstract
The clearance and the factors modulating clearance of PSAP, a glycoprotein excretory-secretory antigen of Schistosoma mansoni, were determined in control and infected mice. After i.v. injection, PSAP was removed rapidly from the circulation of both infected and control mice. The half-life in control mice was about 2.5 min compared to 60 min for the proteoglycan schistosome gut antigen, GASP. Injection of PSAP-containing immune complexes into control mice or of PSAP into infected mice resulted in a prolongation of clearance. In infected mice, the delay in clearance correlated with the amount of anti-PSAP. Marked inhibition of clearance was induced by coinjection of asialofetuin with PSAP, indicating a galactose-mediated clearance mechanism. Furthermore, the clearance of model complexes was delayed to a greater degree after co-injection of asialofetuin than with aggregated gamma-globulin, suggesting that complexes were primarily removed by the galactose receptor. The delay in clearance of antigens may result in immune complex deposition in abnormal locations.
Identification of a viral antigen recognized by H-2-restricted cytolytic T lymphocytes on a murine leukemia virus-induced tumor.
Authors: Plata F , Kalil J , Zilber M T , Fellous M , Lévy D 
Published: December 2022

Abstract
Monoclonal antibodies were produced against protein p30, a structural protein of murine leukemia viruses (MuLV) coded by the gag gene of MuLV. Three monoclonal antibodies of different isotypes (i.e., IgG-1, IgG-2a, and IgG-2b) were chosen for extensive analysis. These three antibodies bound to mouse tumor cells induced by Friend, Moloney, Rauscher, and Gross MuLV, but not to noninfected normal mouse spleen cells. The ability of these monoclonal antibodies to inhibit cytolytic T lymphocyte (CTL) activity by masking the antigens recognized by CTL on the target cell surface was studied in various CTL systems. It was found that the only CTL that were consistently inhibited in their lytic activity came from BALB.B (H-2b) mice immunized against syngeneic Gross MuLV-induced B.GV cells. These results thus showed that a subpopulation of BALB.B anti-Gross MuLV CTL recognized a Gross MuLV gag gene product expressed on the surface of B.GV cells.
Immunologic dysfunction during viral oncogenesis. I. Nonspecific immunosuppression caused by malignant rabbit fibroma virus.
Authors: Strayer D S , Sell S , Skaletsky E , Leibowitz J L 
Published: December 2022

Abstract
Malignant rabbit fibroma virus (MV) is a potent oncogenic poxvirus that produces a rapidly progressive syndrome of disseminated myxosarcoma, immunosuppression, and fatal gram-negative infection. MV is probably a recombinant between Shope fibroma virus (SFV) and rabbit myxoma virus, and is capable of preventing or aborting the in vitro proliferative responses of rabbit lymphocytes to B and T lymphocyte mitogens. Proliferative responses to sheep erythrocytes (SRBC) are similarly affected, although MV does not alter ongoing antibody responses to SRBC. Splenic lymphocytes from MV tumor-bearing rabbits suppress antibody and proliferative responses to SRBC when added to lymphocytes from SRBC-primed rabbits. Finally, lysates of cultured splenic lymphocytes from rabbits given MV suppress both proliferative and antibody-forming responses to SRBC. When MV is removed from these lysates by UV inactivation or by centrifugation, the suppressive activity remains. We therefore conclude that MV induces immunologic unresponsiveness in rabbits by at least two mechanisms. First, a direct suppressive effect of added virus on in vitro lymphocyte proliferation is seen. There is no effect in this situation if an antibody response is already in progress. Second, spleen cells exposed to MV in vivo produce one or more soluble factors capable of suppressing both proliferative and antibody responses of normal lymphocytes.
Functional clonal deletion and suppression as complementary mechanisms operative in adult hapten-induced cytotoxic T cell tolerance.
Authors: Good M F , Nossal G J 
Published: December 2022

Abstract
Immunologic tolerance to the hapten TNP was induced in adult mice through the i.v. injection of reactive TNBS. To probe the cellular basis of the tolerant state, splenic cytotoxic T lymphocyte precursors (CTL-P) were stimulated in vitro with haptenated, x-irradiated syngeneic spleen cells in the presence or absence of exogenously added growth factors derived from Concanavalin A-stimulated spleen cell conditioned medium (CAS). The cultures were either conventional bulk cultures or limit dilution cloning cultures. For the latter, cytotoxicity was assessed through a semi-automated, radioautographic 111In-release assay. Suppressive potential was assessed by mixing spleen cells from tolerant mice with normal spleen cells before culture. In the absence of CAS, bulk cultures showed profound tolerance, and suppressive capacity was clearly evident. Suppression was dependent on the presence of TNP-self during culture and affected the generation of CTL from CTL-P and not the effector function of CTL. Cyclophosphamide treatment did not prevent tolerance induction. In the presence of CAS, bulk cultures still showed marked tolerance, but mixing experiments now yielded no evidence of suppression. As documented previously, limit dilution cultures of tolerant spleen cells in the presence of CAS showed a functional clonal deletion of hapten-specific CTL-P. In the absence of CAS, limit dilution cultures became dependent on helper T cells as the limiting element. Tolerant populations showed a diminution of activatable helper T lymphocyte precursors (HTL-P), which may have been due to a functional clonal deletion of HTL-P and/or a concomitant activation of suppressor T cells. Adoptive transfer studies showed that cells from tolerant mice did not detectably influence the number of hapten-specific CTL-P in the spleens of host animals. Taken together, the results suggest that both functional clonal deletion of CTL-P and suppression of HTL-P contribute to the tolerant state induced.
IgE antibody-mediated cutaneous basophil hypersensitivity reactions in guinea pigs.
Authors: Graziano F M , Gunderson L , Larson L , Askenase P W 
Published: December 2022

Abstract
Cutaneous basophil hypersensitivity (CBH) reactions are a heterogeneous group of delayed time course basophil-rich immune responses that can be mediated in the guinea pig by T cells, B cells, or IgG1 antibody. This study examined whether guinea pig IgE antibody could also mediate CBH reactions. IgE antibody to picryl or oxazolone determinants was induced by immunizing Hartley strain guinea pigs pretreated with cyclophosphamide. Hyperimmune serum from these animals was passed through a heavy chain-specific anti-IgG1 affinity column. The presence of IgE anti-hapten antibody in the filtrate fraction was verified by passive cutaneous anaphylaxis (PCA) testing with a 7-day period of local passive sensitization and by the heat lability (56 degrees C, 4 hr) of PCA activity. This IgE-rich fraction and the IgG1 fraction eluted from the column with base (0.2 M Na2CO3, pH 11.3) were transferred i.v. to separate groups of normal guinea pigs. Both fractions mediated delayed time course reactions that contained basophils. Macroscopic and microscopic reactions mediated by the IgE-rich fraction were abolished with heat (56 degrees C, 4 hr). Thus, two antigen-specific factors in guinea pig serum can mediate delayed time course basophil-containing reactions: IgG1 and IgE antibodies. IgE-mediated CBH reactions are similar to the late-phase reaction that follows IgE-dependent wheal-and-flare reactions in humans. The finding that guinea pig IgE can mediate a late reaction that contains basophils makes this a possible model for the human late-phase response, and suggests that some forms of CBH may play a role in human allergic disease.
Sex steroid receptors in peripheral T cells: absence of androgen receptors and restriction of estrogen receptors to OKT8-positive cells.
Authors: Cohen J H , Danel L , Cordier G , Saez S , Revillard J P 
Published: December 2022

Abstract
The immune response has been reported to be modulated by sex hormones in several models, and estrogen receptors have been demonstrated in the human thymus. We therefore investigated the presence of estrogen and androgen receptors among human peripheral T cells; thoracic duct lymph provided large amounts of circulating lymphocytes. Pure T cells were obtained by negative selection by using complement-dependent cytotoxicity with a monoclonal antibody against a monomorphic determinant of class II histocompatibility antigen (HLA-DR). Furthermore, subsets of OKT8-positive and OKT8-negative lymphocytes were selected by using an OKT8-like monoclonal antibody. Sex steroid binding was determined on purified nuclei; no androgen receptors could be demonstrated on peripheral T cells. The cytoplasmic [3H] 17-beta-estradiol-receptor complex was always translocated to the nucleus in vitro within 1 hr at 37 degrees C; no estrogen receptors were demonstrable on purified OKT4-positive subsets. Assuming that estrogen receptors were evenly distributed among OKT8-positive cells, their level could be estimated to be about 40 fmol/mg DNA. The restriction of estrogen receptors to T cells bearing the "suppressor-cytotoxic" phenotype suggests a possible pathway for the modulation of T cell suppressive activities by estrogens.
Purification and initial characterization of the lymphokine soluble immune response suppressor.
Authors: Aune T M , Webb D R , Pierce C W 
Published: December 2022

Abstract
Two molecular forms of the lymphokine soluble immune response suppressor (SRIS), obtained from serum-free supernatant fluids of a T cell hybridoma producing SIRS, have been purified by a combination of gel filtration and high performance liquid chromatography (HPLC). Supernatant fluids (8 liters) from the hybridoma 393.D2.6 were concentrated and fractionated on Sephadex G-50 in 0.4 M pyridine/0.4 M acetic acid buffer. Active fractions containing approximately 1 X 10(7) units of SIRS activity and 300 mg protein were fractionated further by reverse phase HPLC on a Lichrosorb RP-18 column in a 1.0 M pyridine-0.5 M acetic acid buffer. A stepwise n-propanol gradient reproducibly eluted SIRS activity in the 20% n-propanol fraction. After three chromatography steps on the Lichrosorb RP-18 column, final purification was obtained with an Si-100 diphenyl column by employing the same buffer and elution system. SIRS eluted in the 30% n-propanol fraction as two discrete protein peaks. Purity of SIRS was assessed by SDS-polyacrylamide gel electrophoresis. The two protein peaks from the fractionation on the diphenyl column each exhibited only one band of protein with m.w. of 21,500 and 14,000, respectively. Additional studies of both molecular species of SIRS showed they possessed functional properties identical to those previously described for crude SIRS. Final purification of the 21,500 SIRS species yielded approximately 10 micrograms of protein and 6 X 10(8) units of SIRS activity or 6 X 10(10) units/mg protein; final purification of 14,000 SIRS species yielded approximately 30 micrograms of protein and a similar amount of SIRS activity or 2 X 10(10) units/mg protein.
The antibody response to a single antigenic determinant of the tobacco mosaic virus protein (TMVP): effects of allotype-linked genes and restricted heterogeneity of the response.
Authors: Morrow P R , Rennick D M , Benjamini E 
Published: December 2022

Abstract
The antibody response to a decapeptide antigenic determinant representing residues 103 to 112 of the tobacco mosaic virus protein (TMVP) was studied with the synthetic decapeptide and a panel of its synthetic analogues. The anti-decapeptide response was found to be of restricted heterogeneity and was regulated by heavy chain allotype-linked (V region) genes on at least two levels. One level was whether or not a significant antibody response was made to the decapeptide determinant. Thus, strains with the Igh haplotypes j, o, e, and n were high responders, whereas strains with haplotype Ighb were low responders. The second level of V region gene control was with regard to the fine specificity of the anti-decapeptide antibodies produced. Using the peptide panel to analyze fine specificity, we define two new V region genetic markers, VH-TMVPj and VH-TMVPe.
Idiotypes on monoclonal antibodies to bovine insulin. I. Two public idiotypes on anti-bovine insulin hybridomas define idiotypically distinct families of hybridomas.
Authors: Bender T P , Schroer J , Claflin J L 
Published: December 2022

Abstract
We used isoelectric focusing (IEF) to show that individual mice responding to bovine insulin (BI) present complex spectrotypes that are not conserved between individuals. Competition of 125I-BI-reactive bands with cold BI or cold pork insulin (PI), showed that the majority of the antibody response is sensitive to the two amino acid difference between BI and PI. This difference resides in the three amino acid intrachain disulfide-bonded A-loop. To begin dissection of the antibody response to BI, we prepared a panel of 30 monoclonal antibodies against insulin. Anti-idiotypic sera were produced in guinea pigs against seven of these hybridoma proteins (HP), and two, anti-5. 10C6 and anti-5.2B8, were found to define public idiotypes. The level of the 5.10C6 idiotype is controlled by genes linked to the Igh locus. Both the G.P. anti-5.10C6 and G.P. anti-5.2B8 were found to define distinct groups of idiotypically related HP. The 5.10C6 idiotype group contains three closely related members, 5.10C6, 5.5F10, and 5.4C5, which are shown to bear the same L chain by IEF. The 5.2B8 idiotype group has six members that are less closely related, defined by inhibition solid phase RIA. The two most closely related members of this family, 5.2B8 and 5.3C6, possess co-focusing L chains. Within each idiotype group, however, members were found that bind to distinct determinants on insulin. Four of the members of the 5.2B8 idiotype group appear to bind overlapping determinants on insulin that define a topographic region that includes the three amino acid A-loop. Two other HP that have been shown to bind the A-loop do not bear determinants that cross-react with the G.P. anti-5.2B8 antiserum.
Two-dimensional gel analysis of swine histocompatibility antigens.
Authors: Osborne B A , Lunney J K , Pennington L , Sachs D H , Rudikoff S 
Published: December 2022

Abstract
Miniature swine MHC antigens from three inbred herds were examined by two-dimensional gel electrophoresis. These antigens were found to constitute a series of complex glycoproteins displaying haplotype-specific patterns that allowed the distinction of both class I and class II molecules among the three haplotypes. Selected outbred pig antisera reacted with a subset of class I antigens, suggesting the presence of at least two distinct molecular species among these antigens. Similarly, alloantisera reacting with mouse Ia antigens and a monoclonal anti-human DR were shown to immunoprecipitate a subset of class II molecules. Examination of the cells from two recombinant haplotypes demonstrated that both independent recombinational events took place between the class I and class II genes.