bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new class of inhibitors of lymphocyte mitogenesis: agents that induce erythroid differentiation in Friend leukemia cells.
Authors: Novogrodsky A , Rubin A L , Stenzel K H 
Published: December 2022

Abstract
Addition of the polar organic compounds, dimethylsulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and butyric acid, to human lymphocyte cultures stimulated with the tumor-promoting agent, phorbol myristate acetate, results in greater than 90% inhibition of lymphocyte proliferation. Inhibition is achieved at concentrations of the organic compounds reported to be optimal for induction of erythroid differentiation in Friend leukemia cells. Butyric acid is the most potent compound tested. Compounds that are structurally related to butyric acid, but that do not induce erythroid differentiation, do not inhibit lymphocyte mitogenesis. Lymphocyte responses to other mitogens are also suppressed by the polar organic compounds, although higher concentrations are required. These agents are much less inhibitory when added 24 hr after initiation of the cultures, indicating that they may affect an early phase of lymphocyte activation. Compounds that induce erythroid differentiation in Friend leukemia cells constitute a new class of inhibitors of lymphocyte mitogenesis.
Inductive requirements for the generation of virus-specific T lymphocytes. II. Poxvirus and H-2 antigens associate without cellular or virus-directed protein synthesis, and remain immunogenic in cell membrane fragments.
Authors: Hapel A J , Bablanian R , Cole G A 
Published: December 2022

Abstract
The nature of the interaction between vaccinia virus (VAC) and fibroblastic cells that renders the latter capable of being recognized by virus-specific, H-2 identical murine T lymphocytes has been studied. L cells exposed for 10 min to VAC rendered noninfectious by exposure to ultraviolet light became susceptible targets for cytotoxic T lymphocytes (CTL) without the synthesis of new viral proteins. Susceptibility was retained even if cellular protein synthesis was irreversibly inhibited with pactamycin before virus exposure. Immobilization of cell-surface membranes by glutaraldehyde fixation before (but not after) exposure to virus severely impaired the formation of the "virus + self" complex that in vitro stimulated secondary CTL responses by H-2 identical virus-primed memory cells even though virus attachment to fixed cells were unaffected. This stimulatory complex, once formed, was maintained in membrane fragments prepared from cells previously exposed to VAC. These findings indicate that VAC-specific CTL or their immediate precursors can recognize only those viral envelope antigens that become membrane integrated and that this event requires neither host cell-specific nor virus-specific protein synthesis.
Minimal molecular requirements for reactivity of tumor cells with T cells.
Authors: Hale A H , Lyles D S , Paulus L K , Ruebush M J 
Published: December 2022

Abstract
We have investigated the minimal molecular requirements for T cell recognition of a previously described myeloma tumor (MOPC-315-EL), which reversibly alters its reactivity with T cells. Enucleation of MOPC-315 cells, either sensitive or resistant to reaction with T cells, did not alter the ability of the resulting cytoplasts to elicit or serve as targets for anti-H-2 or anti-Sendai viral cytotoxic T lymphocytes (CTL), despite the fact that there were no detectable differences in serologically defined H-2 or viral antigens on their surface. Likewise, when plasma membranes isolated from sensitive or resistant cells were tested for their ability to elicit anti-H-2 CTL, they retained the phenotype of the cells from which they were isolated. However, solubilized and partially purified H-2 antigens from both sensitive and resistant cells were able to elicit H-2-restricted anti-Sendai virus CTL when incorporated into liposomes with purified viral glycoproteins, and anti-H-2 CTL when incorporated alone into liposomes. These results suggest that a cellular surface component(s) exists that is probably not an H-2K or H-2D gene product and is responsible for the reversible variation in the reactivity of the tumor cells with T cells.
Mitogen-induced plasma cell differentiation in patients with multiple sclerosis.
Authors: Levitt D , Griffin N B , Egan M L 
Published: December 2022

Abstract
Cellular interactions involved in mitogen-stimulated plasma cell differentiation were investigated in eight patients with severe but stable multiple sclerosis (MS). No significant differences were detected between normals and MS patients with regard to percent of B lymphocytes and T lymphocytes in peripheral blood. Autologous and allogeneic combinations of normal and MS B and T cells were stimulated with pokeweed mitogen (PWM) and E. coli lipopolysaccharide (LPS), and plasma cell differentiation was monitored after 7 days in culture. T lymphocytes from patients with MS induced 2- to 4-fold increases in plasma cell development when combined with normal B cell fractions. Allogeneic combinations on normal B and T cells did not provide enhanced plasma cell generation. B lymphocytes from MS patients exhibited poor responses to both PWM and LPS when cultured with their own or normal T cells. Such B cell fractions did not differ from normals with regard to percent monocytes or surface Ig+ B lymphocytes initially contained in these cell populations. We conclude that T cells from MS patients are able to provide excessive help for normal B cell differentiation due either to increased T helper activity or deficient T suppressor activity. B cell differentiation may be diminished in MS patients as a result of a deficiency of a population of B cells in blood that are able to be stimulated by polyclonal B cell activators.
Rat alveolar macrophages are susceptible to activation by free and liposome-encapsulated lymphokines.
Authors: Sone S , Poste G , Fidler I J 
Published: December 2022

Abstract
Alveolar macrophages (AM) obtained from F344 rats were rendered tumoricidal by incubation in vitro with cellfree culture supernatant fluids rich in macrophage-activating factor (MAF) activity harvested from mitogen-stimulated F344 rat lymphocytes. AM activated by this procedure destroyed syngeneic, allogeneic, and xenogeneic tumor cells but were not cytotoxic for nonneoplastic cells. MAF was encapsulated in multilamellar lipid vesicles (liposomes) and its ability to render AM tumoricidal was compared with that of free (unencapsulated) MAF. Liposome-encapsulated MAF rendered AM cytotoxic at concentrations up to 16,000 times lower than free MAF. These data demonstrate that AM can respond in vitro to lymphokines and that MAF encapsulated within liposomes is far more efficient in rendering AM tumoridical than free MAF.
Life-span and size of the trans-membrane channel formed by large doses of complement.
Authors: Ramm L E , Mayer M M 
Published: December 2022

Abstract
To evaluate the life-span and size of trans-membrane channels in complement (C) treated membranes, resealed erythrocyte ghosts containing trapped native protein markers, as well as residual hemoglobin, were treated with anti-Forssman antibody and large doses of guinea pig C. Ovalbumin and hemoglobin were released slowly through the channels so produced, whereas human serum albumin was not. Release of hemoglobin was not blocked by extracellular bovine serum albumin. Release of hemoglobin continued for at least 72 hr at 4 degrees C. Semi-logarithmic plots of ovalbumin or hemoglobin release showed gradual diminution of the rate constant, which indicates slow loss of channels during the experimental period. These experiments demonstrate that the channels produced in erythrocyte ghost membranes by large C doses have a long, although finite, life-span. Their effective diameter is al least 55 A on the basis of ovalbumin and hemoglobin release, and not more than 150 A, since serum albumin was not released. However, an upper limit of 100 A would be more reasonable in light of electronmicroscopic observations by others. These results are compatible with the doughnut model.
Induction of cytotoxic T lymphocytes against herpes simplex virus type i: role of accessory cells and amplifying factor.
Authors: Rouse B T , Lawman M J 
Published: December 2022

Abstract
Spleen cells from mice primed with herpes simplex virus type 1 (HSV-1) could be induced to differentiate into cytotoxic T lymphocytes (CTL) by in vitro culture with infectious HSV-1 but not by heat-inactivated virus. Induction of CTL failed to occur if the spleen cells were depleted of adherent cells by passage over columns of nylon wool before culture with virus. The CTL response could be restored by adding normal syngeneic peritoneal cells (PC) or L cell fibroblasts but not by allogeneic PC or BALB/c 3T3 fibroblasts. Thus, the induction of HSV-1-specific CTL was H-2 restricted. The response of HSV-1-stimulated nylon wool-depleted spleen cells could also be restored by adding amplifying factor (AF) produced in 24 hr mixed lymphocyte cultures. The addition of AF to nondepleted spleen cells also permitted the generation of CTL with heat-inactivated HSV-1 as a viral stimulant. Our results indicated that induction of a HSV-1 CTL response requires two signals, one provided by virus and a second, presumably nonspecific, by helper T cells. It was suggested that only the helper cells require H-2 restriction and need to be presented virus in the context of a macrophage.
Effect of neonatal injection of anti-mu antibodies on immunity to schistosomes (S. mansoni) in the rat.
Authors: Bazin H , Capron A , Capron M , Joseph M , Dessaint J P , Pauwels R 
Published: December 2022

Abstract
The effect of neonatally initiated injections of anti-mu serum on immunity to reinfection with Schistosoma mansoni in the rat was investigated in vitro and in vivo. Anti-mu treatment resulting in a profound depression of immunoglobulin synthesis dramatically decreased immunity to reinfection assessed by worm recovery technique. Complement-dependent antibody, IgG2a antibody-eosinophil-mediated and IgE-macrophage cytotoxicity reactions were in parallel markedly reduced. These results show the prominent role played by antibody-dependent mechanisms in immunity to schistosomes in the rat.
A comparative investigation of the generation of specific T cell-helper function induced by Streptococcus mutans in monkeys and mice.
Authors: Lamb J R , Kontiainen S , Lehner T 
Published: December 2022

Abstract
Antigen-specific helper cells were induced in vitro in monkeys and mice by using an antigen preparation from Streptococcus mutans. These helper cells were T cells on the basis of their sensitivity to anti-Thy. I and complement, and were not retained on nylon wool. Upon further in vitro culture the helper cells release mediators of help, "helper factor" in the supernatant. The release of helper factor as well as its augmentation of the immune response was antigen specific. Monkey and murine helper factors were similar in their induction, function, and specificity.
Activation of human B lymphocytes. XV. Spontaneously occurring and mitogen-induced indirect anti-sheep red blood cell plaque-forming cells in normal human peripheral blood.
Authors: Fauci A S , Whalen G , Burch C 
Published: December 2022

Abstract
A system for the development of indirect (IgG, IgA, and IgM) anti-SRBC plaque-forming cells (PFC) after polyclonal stimulation of human peripheral blood lymphocytes with pokeweed mitogen (PWM) is described. Rabbit anti-human polyvalent Ig or Ig class-specific antisera were employed. Most of the indirect PFC were IgG with less being IgM and IgA. The finding of significantly more indirect IgM PFC than direct PFC suggests that many IgM PFC are producing low efficiency hemolysin that requires an anti-globulin to produce lysis. The system is T cell dependent and cultures require selected batches of supplemented fetal calf serum that preferentially yield indirect (1527 +/- 243 PFC/10(6) lymphocytes) as opposed to direct (36 +/- 11 PFC/10(6) lymphocytes) PFC. Batches of human AB sera that were previously chosen to yield optimal direct PFC (approximately 200 to 300 PFC/10(6) lymphocytes) did not yield indirect PFC. Hence, depending on culture conditions, polyclonal stimulation of human lymphocytes can yield antigen-specific direct and indirect hemolytic PFC.
Glucocorticoids and lymphocytes. I. Increased glucocorticoid receptor levels in antigen-stimulated lymphocytes.
Authors: Crabtree G R , Munck A , Smith K A 
Published: December 2022

Abstract
Recently a 2- to 3-fold increase in the number of glucocorticoid receptors in human peripheral lymphocytes has been noted after in vitro mitogen stimulation. Here, we extend these observations to in vivo immunization. After unilateral immunization of adrenalectomized male rats, a 50% increase in glucocorticoid receptor sites per cell, determined by binding of dexamethasone, was observed in cell suspensions of homolateral lymph nodes over those from the contralateral nonimmunized side of the same animal. The association constant for dexamethasone was similar in both groups, as was the stereospecificity for various steroids, the time course of cytoplasmic and nuclear association, and cytoplasmic-to-nuclear translocation. Despite a 50% increase in the number of glucocorticoid receptor sites per cell, the cells from the homolateral and controlateral lymph nodes were equally sensitive to the inhibitory effects of dexamethasone, as determined by measurements of the incorporation of radiolabeled precursors of protein, RNA, and DNA, or measurements of in vitro cell survival.
Specificity of alloreactive T lymphocytes that adhere to lung stage schistosomula of Schistosoma mansoni.
Authors: Brown A P , Burakoff S J , Sher A 
Published: December 2022

Abstract
Alloreactive T lymphocytes generated against MHC antigens have previously been shown to adhere to lung stage schistosomula of S. mansoni because of the host MHC products known to be present on the surface of the parasites. In experiments reported here, the cells in this adherent population were shown to consist of Ly-2 positive, Thy-1 positive lymphocytes and to react specifically with products of the K and D but not the I region of the MHC. These results strengthen previous findings suggesting that the adherent lymphocytes are CTL.
Ecto-5'-nucleotidase activity in lymphoblastoid cell lines derived from heterozygotes for congenital X-linked agammaglobulinemia.
Authors: Thompson L F , Boss G R , Spiegelberg H L , Bianchino A , Seegmiller J E 
Published: December 2022

Abstract
Lymphoblastoid cell lines were established from female relatives of patients with congenital X-linked-agammaglobulinemia by Epstein-Barr virus transformation of their peripheral B lymphocytes. Cell lines derived from presumed carriers were characterized by low ecto-5'-nucleotidase activity and a reduced percentage of surface immunoglobulin-bearing cells. Measurement of ecto-5'-nucleotidase activity in newly established lymphoblastoid cell lines may provide a means for the identification of heterozygotes for congenital X-linked agammaglobulinemia.
EBV-transformation of surface IgA-positive human lymphocytes.
Authors: Steinitz M , Klein G 
Published: December 2022

Abstract
Surface IgA-positive human lymphocytes were selected, separated, and immortalized with Epstein-Barr virus (EBV). Selection was carried out by rosetting the cells with ox erythrocytes, coated with rabbit anti-human IgA immunoglobulin, followed by separation on Ficoll-Isopaque. Stable monoclonal lines were established by cloning in agarose. This shows that EBV-transformation is not restricted to the IgM-positive B cell category but can be extended to minority classes of B lymphocytes. The method provides the means to establish other minority categories as continuous lines, depending on the efficiency of the preselection procedure.
Delayed hypersensitivity in mice infected with reovirus. I. Identification of host and viral gene products responsible for the immune response.
Authors: Weiner H L , Greene M I , Fields B N 
Published: December 2022

Abstract
Delayed-type hypersensitivity (DTH) can be demonstrated in mice infected with reovirus by challenging primed animals in the footpad with virus. Maximal responses occur 7 days after immunization with as little as 10(5) viral particles. DTH to reovirus is transferable by lymph node cells and is mediated by T cells as the transfer of reactivity can be abrogated by treatment of cells with anti-Thy 1.2 plus complement. DTH to reovirus is serotype specific, animals infected with reovirus type 1 or 3 only develop DTH responses when challenged with the same serotype with which they were infected. Using recombinant viral clones containing genes from both parental serotypes, we have demonstrated that the S1 gene, the gene encoding the viral hemagglutinin, determines serotype specificity. Furthermore, in adoptive transfer experiments between mice of varying histocompatibility backgrounds, it was found that D or K, IA-IB region identity was required for the transfer of reactivity. These studies demonstrate that specific host and viral genes determine the in vivo cellular immune response to reovirus and should allow a more precise definition of the host cellular immune response to viral antigens.
Surface markers on the T cells that regulate cytotoxic T cell responses. II. Distribution of Ly 6.1 and Ly 7.2: selective expression of Ly 7.2 on helper T cell effectors.
Authors: Pilarski L M , Al-Adra A R , McKenzie I F 
Published: December 2022

Abstract
Helper T cells and suppressor T cells can be generated in vitro, yielding effector cells with radioresistant function that regulate a cytotoxic T cell response to alloantigen. The Ly 6.1 and Ly 7.2 antigen phenotype of these regulatory effector cells has been determined. Ly 7.2 was found to be selectively expressed on helper T cells; neither the suppressor cells nor the cytotoxic cells analyzed here were found to bear Ly 7.2 antigens. Mixing experiments demonstrated that the helper cell bears both Ly 1.1 and Ly 7.2. Removal of help by anti-Ly 7.2 treatment frequently enhanced suppressor activity. Suppressive activity was partially depleted by treatment with anti-Ly 6.1; helper cell activity was unaffected by such treatment. Cytotoxic T cell precursors bear neither Ly 6.1 nor Ly 7.2, but approximately half of the cytotoxic T cell effectors did bear Ly 6.1; none bore Ly 7.2. Analysis of populations depleted of 7.2-bearing cells should therefore allow the design of experiments that will increase our understanding of the interactions of various regulatory cell populations in the control of a cytotoxic T-cell response.
A peptide difference between the mu-chains from cell-associated and secreted IgM of the BCL1 tumor.
Authors: Yuan D , Uhr J W , Vitetta E S 
Published: December 2022

Abstract
The murine B cell tumor, BCL1, bears monomeric IgM lambda on its surface. After stimulation in vitro with LPS, the cells secrete pentameric IgM lambda. Comparison of mu-chains from radiolabeled intracellular, surface, and secreted IgM indicates that mu-chains from the three sites have different apparent m.w. Since the observed differences are analogous to those reported for normal murine lymphoid cells, the BCL1 cells were used for determining the structural basis for the differences in m.w. of mu-chains from the above sites. Comparative peptide analysis was performed on mu-chains from cell associated and secreted IgM. Approximately 25 peptides were identified after digestion with chymotrypsin and trypsin and analysis of peptides by cation exchange chromatography. All peptides co-eluted with the exception of a single extra peptide derived from the Fc portion of the secreted IgM. The same peptide was observed in a similar analysis using mu-chains from IgM secreted by normal splenocytes.
Isolation and characterization of calmodulin from a murine macrophage-like cell line.
Authors: Jamieson G A , Vanaman T C 
Published: December 2022

Abstract
Several lines of evidence implicate fluxes in the intracellular levels of CA++ and the cyclic nucleotiodes in the chemotactic, phagocytic, and cytotoxic responses of macrophages. Calmodulin, a ubiquitous small acidic Ca-binding protein, appears to link the intracellular second messengers--Ca++ and the cyclic nucleotides--through its ability to regulate numerous central metabolic enzymatic activities. A pure protein has been isolated and characterized from the macrophage-like cell line, P388D. This protein has been identified as calmodulin by demonstrating three of the Ca-dependent activities attributed to calmodulins. P388D calmodulin also has physiochemical properties similar to those of the previously characterized mammalian proteins. This study is the initial step of an examination of the role of this central regulatory protein in responses elicited by macrophages to external stimuli.
Production of a suppressor factor by human adherent cells treated with mycobacteria.
Authors: Wadee A A , Sher R , Rabson A R 
Published: December 2022

Abstract
Human peripheral blood mononuclear cell (MN) proliferation and lymphokine production induced by mitogen could be inhibited by heat killed whole mycobacteria. The inhibition was induced by a wide variety of mycobacteri but not by other Gram-positive or Gram-negative organisms or by latex particles. Proliferation and lymphokine production by adherent cell-depleted lymphocytes was not inhibited by these organisms. Adherent cells treated with mycobacteria had the ability to inhibit lymphocyte blastogenesis when co-cultured with the lymphocytes. the inhibitory effect of these adherent cells was due to the release of a heat stable, nondialyzable suppressor cells. These latter cells, which were T gamma cells, could inhibit the blastogenic ability of normal lymphocytes activated by mitogens. The results suggest that in situations of high mycobacterial load, adherent cells are activted to release a suppressor factor that will activate lymphocytes to become suppressor cells. This mechanism may explain the anergy associated with lepromatous leprosy or advanced tuberculosis.
A spatial association between membrane IgD and the receptor for C3b (CR1) at the cell surface of murine B lymphocytes.
Authors: Sitia R , Rabellino E M , Sockell M , Hämmerling U 
Published: December 2022

Abstract
Surface immunoglobulin D (SIgD) and receptors for C3b (CR1) were demonstrated to be closely associated at the surface of mouse spleen lymphocytes. When SIgD was modulated by incubation at 37 degrees C with heteroantisera (rabbit) or monoclonal alloantibodies specific for delta-chains, the number of splenocytes capable of forming rosettes with EAC1-3b decreased by about 40%, whereas a smaller effect (13%) could be observed when EAC1-3d (indicators for CR2) were used. Antibodies to surface IgM were not inhibitory, ruling out the possibility of nonspecific inhibition of the C receptor sites by antigen-antibody complexes formed at the cell surface. In addition, co-capping of IgD and cR1 was observed on 65% of the cells expressing both markers. In these experiments IgM was shown to redistribute independently from both CR1 and CR2. CR2 and IgD also capped independently. Taken together with the observations that IgD and CR are ontogenetically related and that they have in common certain biologic properties (such as sensitivity to proteolytic enzymes and rate of turnover), these data suggest a functional relationship between the 2 surface receptors. A possible role in the mechanism of B lymphocyte triggering is discussed.