bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thymidine transport in human lymphocytes stimulated with concanavalin A: effect of colchicine.
Authors: Rudd C E , Kaplan J G 
Published: December 2022

Abstract
Concanavalin A (Con A) was found to induce the appearance of time-dependent and saturable thymidine transport in human peripheral lymphocytes with a Km that ranged from 200 to 500 microM and a Vmax of between 5 to 8 pmols/cell/sec; transport of thymidine could not be demonstrated in resting cultures. Colchicine was found to cause the disappearance of microtubular networks in the majority of cells in the population, whereas lumicolchicine as expected had no significant effect on the presence of microtubules. Lumicolchicine caused 50% inhibition of thymidine transport and of DNA synthesis at a concentration of about 10(-4) M; the effect of this agent on the transport of thymidine could account for its ability to inhibit DNA synthesis. Colchicine also inhibited the transport of thymidine by 50% at about 10(-4) M. However, half-maximal DNA synthesis occurred at a colchicine concentration of 5.0 X 10(-8) M; thus, the effect of this drug on transport cannot account for its effect on DNA synthesis, since the latter process is some 3 orders of magnitude more sensitive than the former. The ability of colchicine to inhibit DNA synthesis in Con A-stimulated human lymphocytes would appear to be an indirect consequence of disassembly of microtubules.
Inhibition of T cell-mediated cytolysis by monoclonal antibodies directed against Lyt-2: heterogeneity of inhibition at the clonal level.
Authors: MacDonald H R , Thiernesse N , Cerottini J C 
Published: December 2022

Abstract
The inhibitory effect of monoclonal anti-Lyt-2 antibodies on T cell-mediated cytolysis has been investigated at the clonal level. In agreement with previous reports from several laboratories, populations of cytolytic T lymphocytes (CTL) generated in vitro in mixed leukocyte cultures (MLC) were reversibly inhibited by monoclonal anti-Lyt-2 antibodies in a dose-dependent fashion. However, when alloimmune peritoneal exudate lymphocytes (PEL) were used as a source of CTL, little or no inhibitory effect of anti-Lyt-2 antibodies on cytolysis was observed. A series of CTL clones derived from MLC or PEL populations was also tested for inhibition of cytolysis by anti-Lyt-2 antibodies. In agreement with results obtained at the population level, most MLC-derived clones (81%) were strongly inhibited by the reagent, whereas few PEL clones (15%) were inhibited. Several of these clones were expanded and maintained in culture without loss of their "inhibition phenotype." Flow cytofluorometric analysis using the same monoclonal anti-Lyt-2 antibodies further revealed that both inhibited and uninhibited clones expressed comparable amounts of Lyt-2 antigen. These results provide direct evidence that inhibition of CTL by anti-Lyt-2 antibodies is heterogeneous at the clonal level. The possibility that this heterogeneity may be related to avidity of antigen receptors is discussed.
Influenza A2 inhibits murine in vitro antibody synthesis.
Authors: Daniels C A , Marbrook J 
Published: December 2022

Abstract
A2 influenza inhibited in a dose-dependent fashion the in vitro antibody-forming cell (AFC) response of CBA mouse spleen cells to sheep erythrocytes. The greatest amount of inhibition occurred if virus was added to the splenocytes on the day the cells were placed in culture. Inoculation of spleen cells with influenza on day 3 of culture or immediately before assay on day 4 had no effect on the AFC response. Experiments indicated that the inhibition could be transferred by adding viable, infected cells to uninfected spleen cultures. The origin of the cells that caused the suppression of AFC was not resolved; however, the data suggest that infected B or T cells were not solely responsible for the inhibition. Although infectious virus was most effective, inactivated influenza preparations also suppressed the AFC response. The possible in vivo significance of influenza's inhibitory effect on antibody synthesis is discussed.
Expression of influenza A virus internal antigens on the surface of infected P815 cells.
Authors: Yewdell J W , Frank E , Gerhard W 
Published: December 2022

Abstract
A panel of hybridoma antibodies was used to study the expression of the 2 major internal influenza A virus proteins, matrix protein (M), and nucleoprotein (NP) on the surface of influenza A-infected P815 cells. Using a sensitive radioimmunoassay (RIA) performed with live infected P815 cells only minute amounts of M were detectable, whereas M was not detected in 3 other cell-surface assays. In contrast, NP was detected in 10-fold greater amounts than M and 10- to 50-fold lower amounts than the viral glycoproteins by RIA. Furthermore, the presence of NP could be demonstrated by immunofluorescence, microcytotoxicity, and agglutination assays performed on live infected cells.
Macrophage triggering by aggregated immunoglobulins. I. Delayed effect of IgG aggregates or immune complexes.
Authors: Pestel J , Joseph M , Dessaint J P , Capron A 
Published: December 2022

Abstract
Rat peritoneal macrophages in serum-free cultures were triggered to release lysosomal enzymes or plasminogen activator and to incorporate glucosamine upon exposure to rat IgG that was nonspecifically aggregated after heating or by dimethylsuberimidate cross-linking or was specifically complexed by the corresponding antigen using preformed BSA-anti-BSA immune complexes. A lag period of 6 hr was observed before the increase in enzyme release or in glucosamine uptake. Although chemically prepared dimers of IgG were found sufficient to trigger the macrophages, both enzyme release and glucosamine incorporation increased with the size of the IgG aggregates. Similarly, immune complexes in IgG antibody excess (Ag/Ab ratio 1:32) were more efficient than complexes prepared at equivalence or in antigen excess, which suggests that the size of the aggregates is an important parameter of macrophage triggering. The participation of the macrophage Fc receptor for IgG in IgG-dependent macrophage triggering is suggested by similar findings using a first exposure of the cells to rat IgG then the cross-linking the cell-bound immunoglobulin by purified anti-rat IgG or the F(ab')2 fragment of it. Macrophage function in inflammatory reaction might thus be modulated by the size of IgG immune complexes.
Characterization of a human B cell-specific antigen (B2) distinct from B1.
Authors: Nadler L M , Stashenko P , Hardy R , van Agthoven A , Terhorst C , Schlossman S F 
Published: December 2022

Abstract
A human B lymphocyte-specific antigen (B2) was identified and characterized by the use of a monoclonal antibody. By indirect immunofluorescence and quantitative absorption, B2 was shown to be expressed exclusively on Ig+ B cells isolated from peripheral blood and lymphoid tissues. In contrast, B2 was not found on monocytes, resting and activated T cells, Null cells, or granulocytes, nor was it found on cell lines or tumor cells of T cell or myeloid origin. Functional studies demonstrated that only B2 antigen-positive splenocytes could be induced to differentiate into plasma cells under the stimulus of pokeweed mitogen, further confirming the B cell specificity of B2. It was then demonstrated that the B2 antigen was distinct from the previously described B cell-surface determinants including surface immunoglobulin, Ia-like antigens, and Fc and C3 receptors. More importantly, the B2 antigen has been clearly shown to be distinct from the previously described B cell-specific antigen, B1, by its m.w. and expression on normal and malignant B lymphocytes. The distinct distribution of B2 on normal and malignant lymphocytes supports the notion of B cell heterogeneity and provides further evidence for existence of subpopulations of human B lymphocytes.
Functional analysis of human T cell subsets defined by monoclonal antibodies. III. Regulation of helper factor production by T cell subsets.
Authors: Thomas Y , Sosman J , Rogozinski L , Irigoyen O , Kung P C , Goldstein G , Chess L 
Published: December 2022

Abstract
In the present report we extended our previous studies demonstrating that obligatory T-T interactions are important in regulating human immune responses in vitro. Functionally distinct human T cell subsets were isolated by complement-mediated lysis using the monoclonal antibodies OKT4 and OKT8. Evidence was obtained that during allogeneic interactions, OKT4+, but not OKT8+, responder T cells are required to generate helper factor(s) capable of polyclonally activating human B cells independent of additional T cell help. Importantly, the alloantigen-induced helper factor(s) production and/or release was found to be suppressed by addition of graded numbers of radiosensitive OKT8+ cells. On the other hand, no evidence was obtained that supernatant derived from alloactivated OKT8+ cells could counterbalance the helper activity generated in the presence of supernatant from alloactivated OKT4+ cells. Furthermore, OKT8+ cells, known to suppress PWM-driven B cell differentiation in the presence of OKT4+ cells, do not suppress B cell differentiation induced by preformed helper factor even in the presence of OKT4+ cells. These data further underscore the importance of functional T-T interactions in immunoregulation in vitro and support the idea that the target of suppression of B cell differentiation, induced either by alloantigen-triggered helper factor or PWM, are OKT4+ cells and not B cells themselves.
Studies on human migration inhibitory factor: characterization of three molecular species.
Authors: Weiser W Y , Greineder D K , Remold H G , David J R 
Published: December 2022

Abstract
Human migration inhibitory factor (MIF), obtained from supernatants of peripheral blood mononuclear cells stimulated with concanavalin A, was analyzed by gel filtration, isoelectrofocusing, and CsCl density gradient centrifugation. A distinct pattern of heterogeneity was determined on the basis of its harvesting time and biochemical criteria. Supernatants from cells cultured for 1 day contained a single peak of MIF activity with an isoelectric point of 4.3 to 5.2, an apparent m.w. of 23,000, and a density of 1.314 g/ml, the same as the density of the marker protein, 125I-HSA (1st day pH 5-MIF). Furthermore, this species of human MIF was sensitive to treatment with trypsin, strongly suggesting its being a protein, but not to treatment with neuraminidase and corresponds therefore to guinea pig pH 5-MIF. However, when 2nd day supernatants were analyzed under the same conditions, 2 MIF species were found. One species with an isoelectric point of 2.4 to 3.3 had an apparent m.w. of 65,000 (2nd day 3-MIF). The other species with an isoelectric point of 4.3 to 5.6 had an apparent m.w. of 23-43,000 (2nd day pH 5-MIF). Upon centrifugation in CsCl density gradients, the density (rho 25 of 1.314 to 1.414 g/ml) of both species was found to be greater than that of the pure protein, 125I-HSA. In addition, both species were chymotrypsin and neuraminidase sensitive but not trypsin sensitive, further suggesting their glycoprotein nature.
The first component of human complement: on the mechanism of activation by some carbohydrates.
Authors: Schultz D R , Arnold P I 
Published: December 2022

Abstract
Four synthetic saccharides (mono-, di-, tri-, tetra-) linked to the carrier 8-methoxycarbonyloctanol were used in the presence or absence of a polysaccharide (PS) purified from ant venom to study the activation of C1 and the consumption of C4 in normal serum. The carrier was essential for the recorded activities of the saccharides. The alpha D mannose-O-carrier did not cause C1 activation and C4 consumption by itself, but it enhanced these activities when combined with the venom PS. The alpha L fuc(1 leads to 4)beta D glc-NAc-O-carrier caused C1 activation but no C4 consumption by itself at a high concentration (1.4 mg/ml), and enhanced C1 activation and C4 consumption in combination with the venom PS. The beta D gal(1 leads to 3)alpha L fuc(1 leads to 4)beta D glc-NAc-O-carrier caused both C1 activation and C4 consumption in normal human serum by itself. The alpha L fuc(1 leads to 2)beta D gal[alpha L fuc(1 leads to 4)]beta D glc-NAc-O-carrier neither caused C1 activation and C4 consumption by itself, nor did it enhance these activities when combined with the venom PS. Neither EAC1hu nor EAC1hu bound 3H-PS or 3H-beta D gal(1 leads to 3)alpha L fuc(1 leads to 4)beta D glc-NAc-O-carrier. Also, the precursor human C1 on EA (EAC1) was not activated by the venom PS. Thus, the overall evidence shows that human precursor C1 is activated by these carbohydrates solely by an interaction with C1q subunit of macromolecular C1.
Generation of suppressor cells in the response of human lymphocytes to a polysaccharide from Candida albicans.
Authors: Piccolella E , Lombardi G , Morelli R 
Published: December 2022

Abstract
MPPS stimulation of human lymphocytes is characterized by a 2-way cooperation phenomenon, i.e., T help of B cells and B help of T cells. In this system suppressor cells are generated after 6 days of culture. They were characterized as Ia- T cells. Their suppressor activity affected both T and B cell stimulation, and it may involve 2 different mechanisms: direct cell suppression, and interaction with soluble helper factors.
Chemotaxis by mouse macrophage cell lines.
Authors: Aksamit R R , Falk W , Leonard E J 
Published: December 2022

Abstract
Five mouse macrophage cell lines were tested for chemotaxis and phagocytosis. All 5 cell lines ingested sheep red cells coated with rabbit IgG anti-Forssman antibody and exhibited chemotaxis to endotoxin-activated mouse serum (EAMS) and lymphocyte-derived chemotactic factor. Two cell lines were tested for chemotaxis to f-Met-Leu-Phe and neither responded. Four of the cell lines (RAW264, RAW309CR, PU5-1R, and WR19M.1) exhibited chemotaxis to C5a. These cell lines displayed a 1- to 2-hr lag before migrating toward EAMS, and chemotaxis was dependent upon cell density. When fewer than 10(3) cells were present per mm2 of filter surface, less than 10% of the cells migrated; however, at a density of 5 X 10(3) cells/mm2 50 to 70% of the cells migrated. WEHI-3 differed from the other cell lines in that there was no chemotaxis to C5a, migration to EAMS did not have a detectable lag, and there was no cell density dependence for chemotaxis. Comparison of these chemotactic properties with those reported in the literature for mouse macrophages and monocytes suggests that RAW264, RAW309CR, PU5-1R, and WR19M.1 have properties that are similar to those of mouse resident macrophages, whereas WEHI-3 may have some of the properties of mouse monocytes.
Macrophage content of metastatic and nonmetastatic rodent neoplasms.
Authors: Talmadge J E , Key M , Fidler I J 
Published: December 2022

Abstract
In this study, we have examined the macrophage content of 16 different rodent tumors and failed to demonstrate a correlation between the extent of macrophage infiltration into neoplasms and the metastatic behavior of the tumor. We also did not find a correlation between the macrophage content of ultraviolet radiation- (UV) induced murine fibrosarcomas growing in normal or UV-irradiated syngeneic mice and the immunogenic potential of the tumor. After s.c. inoculation of single viable cells, tumors with a high level of infiltrating macrophages required a longer induction period to form palpable tumors than tumors with low macrophage content. The macrophage content of neoplasms also did not correlate with in vitro or in vivo growth rates. We conclude that no generalizations can be drawn regarding the relationship between macrophage content of neoplasms and their metastatic potential.
Characterization of colon-specific antigen-p and isolation of immunologically active tryptic peptides.
Authors: Shochat D , Archey R L , Pant K D , Dahlman H L , Gold D V , Goldenberg D M 
Published: December 2022

Abstract
CSAp was originally detected with antisera to an unfractionated extract of GW-39 human colonic carcinoma xenografts, and was determined to be restricted to normal and neoplastic gastrointestinal tissues and certain ovarian tumors. Gel filtration chromatography of GW-39 extract on Sepharose 4B columns reveals that more than 90% of the CSAp is associated with the void volume fraction. The smaller m.w. CSAp fraction is a population of fragments heterogeneous in respect to size but immunologically identical to the void CSAp. Efforts to dissociate intact CSAp from the void fraction by treatment with solutions of high ionic strength, SDS, non-ionic detergents, and 1 M lithium bromide have not been successful. CSAp is a glycoprotein that binds to Sepharose-concanavalin A and is distinct from other known tumor-associated antigens in immunologic and physicochemical properties. The antigen shows sensitivity to high concentrations of chaotropic reagents and especially to sulfhydryl reagents, even in low concentrations, which supports earlier results indicating that the CSAp antigenic determinant is associated with the polypeptide chain rather than with a carbohydrate moiety. CSAp has been reduced in size by either sonication or partial tryptic digestion. The former produces immunologically active fragments, heterogeneous in respect to size, that resemble the smaller size CSAp, whereas the tryptic digest generates 2 distinct peptides. The major tryptic peptide is found to have an approximate molecular size of 120,000, as determined by gel filtration.
Lymphoid cell surface receptor for Moloney leukemia virus envelope glycoprotein gp71. I. Binding characteristics.
Authors: Choppin J , Schaffar-Deshayes L , Debré P , Lévy J P 
Published: December 2022

Abstract
The characteristics of Moloney leukemia virus (M-MuLV) gp71 binding on lymphoid cells have been studied by a very sensitive assay. Analysis of the results indicated the presence of 1 class of high affinity binding sites (Ka = 1.2 X 10(9) M-1) on BALB/c thymus cells. The total number of binding sites was estimated around 1.3 X 10(4) per thymus cell. No significative differences were observed for the binding of Moloney leukemia virus gp71 on thymus cells from different inbred strains of mice, suggesting that the genetic susceptibility to Moloney leukemia virus infection does not depend on the presence of gp71 receptor on the target cells. On the other hand, it seems that M-MuLV gp71 binds preferentially on T cells, which are the final target of Moloney leukemia virus-induced transformation. Very little binding was found on Moloney, Rauscher, or x-ray-induced lymphoma cells.
Murine transfer factor. I. Description of the model and evidence for specificity.
Authors: Petersen E A , Greenberg L E , Manzara T , Kirkpatrick C H 
Published: December 2022

Abstract
A model for studying transfer of delayed-type sensitivity to mice with cellfree materials is described. The results with a particulate antigen (Candida) and 4 soluble protein antigens (PPD, ferritin, cytochrome c, and horseradish peroxidase) suggest that the phenomenon is antigen specific. Identical preparations from the spleens of insensitive donors were not active. This murine model should facilitate characterization of the immunologic and chemical properties of transfer factor.
Expression of cell-surface latent allotypes: latent specificities are synthesized only by cells that display the nominal allotype.
Authors: Wolf B , Currie E P , Yarmush M 
Published: December 2022

Abstract
The association of latent and nominal allotypes at the cell surface of rabbit peripheral blood lymphocytes (PBL) was studied in animals from 2 closed group colonies. The specificity of the anti-allotype antibodies used in the mixed antiglobulin rosette test was confirmed by radioimmune assay and by testing PBL from latent allotype-free homozygotes. PBL from rabbits exhibiting latent group a and b allotypes were treated with pronase to bring the rosetting population down to less than 1 to 2%; latent and nominal cell-surface allotypes were then regenerated overnight in serum-free culture. Latent and nominal allotypes were detected in the same cell in 16 to 57% of the total allotype-bearing population. The remaining cells displayed only nominal allotype. This was observed in rabbits bearing latent a1, a2, a3, b4, b5, and b6. Rosette-inhibition data indicated that some of the group a latent and nominal allotypes were contiguously associated at the cell surface but that the group b latent and nominal markers were spaced further apart. In addition, in rabbits exhibiting 2 latent group b allotypes, both single and double latent cell surface expression was seen. Rabbits from the Philadelphia and N.I.H. internally derived colonies gave similar results.
Ia-bearing macrophages in athymic mice: antigen presentation and regulation.
Authors: Lu C Y , Peters E , Unanue E R 
Published: December 2022

Abstract
Ia-bearing macrophages from spleens and peritoneal cavities of athymic (nu/nu) and euthymic (nu/+) were compared. Macrophages from both strains of mice had equal antigen-presenting ability. The basal numbers of unstimulated Ia-bearing peritoneal macrophages were equal, but only euthymic mice recruited large numbers of Ia-bearing macrophages after Listeria infection. The i.p. injections of a "macrophage Ia-recruiting factor" induced exudates rich in Ia-bearing macrophages in both athymic and euthymic mice. These data suggest 2 levels of control of Ia-bearing macrophages: a basal T cell-independent level and a stimulated level dependent on mature T cells.
In vitro killing of S. mansoni schistosomula by lymphokine-activated mouse macrophages.
Authors: Bout D T , Joseph M , David J R , Capron A R 
Published: December 2022

Abstract
Inflammatory macrophages from mice i.p. injected with FCS 24-hr before harvesting, activated by partly purified MAF from Con A-stimulated spleen cells, were shown to kill an average of 60.9% (SE +/- 5.3) of the parasites in cultures of Schistosoma mansoni schistosomula. On the contrary, resident macrophages were not cytotoxic under the same conditions. The degree of macrophage activation for the killing was dependent upon both lymphokine concentration and time of incubation in lymphokine. The capacity of macrophages to be activated to kill schistosomula as well as the schistosomulicidal activity of the lymphokine-activated macrophages were short-lived properties. The killing was strongly influenced by the effector-to-target ratio. The results are consistent with other data on the immune response in experimental infection and particularly the development of the delayed hypersensitivity. Therefore, among the immune mechanisms that participate in immunity to reinfection, cell-mediated immunity that involves inflammatory macrophages should no longer be restricted to microorganisms and protozoans and could be extended to multicellular parasites like schistosomes.
Inhibitory effect of K-76 monocarboxylic acid, an anticomplementary agent, on the C3b inactivator system.
Authors: Hong K , Kinoshita T , Kitajima H , Inoue K 
Published: December 2022

Abstract
K-76COOH caused dose-dependent inhibition of the degradation, by C3b inactivator (C3bINA) and beta 1H, of membrane-bound C3b on EAC1-3b and of free C3b in the fluid phase, i.e., cleavage of the C3b alpha' peptide chain. K-76COOH primarily attacked C3bINA but not beta 1H or C3b. K-76COOH inhibited the suppression of immune adherence reactivity and the manifestation of conglutination reactivity of EAC1-3b cells by C3bINA and beta 1H. The drug also inhibited the reaction between conglutinin and EAC1-3b' cells derived from EAC1-3b by treatment with C3bINA and beta 1H. EAC1-3b cells did not form rosettes with either Daudi or Raji lymphoblastoid cells. Treatment with C3bINA and beta 1H rendered EAC1-3b cells reactive with Daudi cells, and this change was inhibited by K-76COOH. EAC1-3b cells became able to form rosettes with Raji cells after addition of beta 1H. This rosette formation was enhanced by further addition of C3bINA, and this enhancement was also suppressed by K-76COOH.