bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanism of lymphocyte activation. II. Requirements for macromolecular synthesis in the production of lymphokines.
Authors: Varesio L , Holden H T , Taramelli D
Published: December 2022

Reversible inhibitors of protein synthesis, cycloheximide and puromycin, and an irreversible inhibitor of RNA synthesis, actinomycin D, were employed to study the kinetics and types of macromolecular synthetic events required for the production of migration inhibitory factor (MIF) and macrophage activating factor (MAF) by Con A-stimulated lymphocytes. Reversible inhibition of protein synthesis during the first 2 hr of stimulation completely inhibited MIF and MAF production. The same treatment, performed 4 hr after the beginning of the stimulation, had no effect. When the inhibitors of protein synthesis were left in the cultures, a block of lymphokine production was observed when the drugs were added at 6 hr as well as at time 0. In contrast, irreversible inhibition of RNA synthesis at 6 hr was ineffective and only treatment at the beginning of culture blocked lymphokine production. These data suggest that a critical protein is synthesized during the first few hours of stimulation, which is required for subsequent production of lymphokines. After this special early requirement, however, continued protein synthesis is needed for lymphokine production. In contrast, the RNA required for MIF and MAF production seemed to be completely synthesized within 4 to 6 hr of stimulation. The possibility that suppressor macrophages inhibit lymphokine production via modulation of macromolecular synthesis is discussed.
Long-term survival of murine allogeneic bone marrow chimeras: effect of anti-lymphocyte serum and bone marrow dose.
Authors: Norin A J , Emeson E E , Veith F J
Published: December 2022

Graft-vs-host disease (GVHD) and failure of donor stem cells to engraft permanently are two major obstacles to successful bone marrow transplantation. We evaluated the effect of a single large dose of anti-lymphocyte serum (ALS) on mice receiving various numbers of H-2 incompatible bone marrow cells. Most animals receiving lethal total body irradiation (TBI) and allogeneic marrow died within 45 days due to GVHD, A/J (H-2a), CBA/J (H-2k), and DBA/1J (H-2q) mice that were given ALS 6 to 24 hr before TBI and C57BL/6 (B6, H-2b) bone marrow 24 hr after irradiation survived in good health for more than 200 days. This result compared quite favorably with mice that received anti-Thy 1.2 and C-treated B6 bone marrow (90% survival at 100 days, 50% survival at 200 days). Engraftment of the allogeneic marrow was dose dependent. At 100 days after TBI, about 30% of the A/J mice given 2 x 10(6) bone marrow cells were complete chimeras, i.e., donor H-2 antigens could be detected on greater than 85% of the peripheral blood mononuclear leukocytes of these mice. However, at a dose of 1 x 10(7) B6 bone marrow cells, 95% of the A/J mice were complete chimeras. Spleen and bone marrow from B6 leads to A/J chimeras and B6 leads to CBA chimeras were unable to induce lethal GVHD in TBI-treated mice that were syngeneic to the recipient. However, these cell preparations caused lethal GVHD in third party mice indicating that the lack of alloreactivity was specific to the strain in which the unresponsiveness was originally induced.
In in vitro production and cloning of the P cell, a bone marrow-derived null cell that expresses H-2 and Ia-antigens, has mast cell-like granules, and is regulated by a factor released by activated T cells.
Authors: Schrader J W
Published: December 2022

A technique, based on selective culture conditions, is described for the preparation from mouse spleen of a pure population of Ig-negative, Thy.1-negative and Lyt.1- and Lyt.2-negative nonadherent cells, termed persisting (P) cells. Antigens coded for by the H2-K, H2-D, and I regions were readily detectable on the surface of P cells. P cells grew for long periods in vitro provided that a factor produced by activated T cells, but distinct from T cell growth factor, was present. It was demonstrated that P cells were bone marrow derived. When P cells were examined in suspension, a variable number of fine cytoplasmic projections could be seen waving from the cell, often at 1 pole. The nuclei varied in shape, being round, in general, but with bilobed and irregular forms occurring, and the cytoplasm contained large numbers of characteristic metachromatic granules. P cells had readily detectable Fc receptors but did not phagocytose latex particles or antibody-coated erythrocytes. P cells formed colonies in soft agar in the presence of growth factors, and cloned lines could be propagated from these colonies. The relationship of P cells to mast cells and Ia-positive accessory cells and their possible role in T cell activation is discussed.
Alloimmune cytolytic T lymphocyte activity: triggering and expression of killing mechanisms in cytolytic T lymphocytes.
Authors: Wei W Z , Lindquist R R
Published: December 2022

Nonspecific target cells were bound to alloimmune cytolytic T lymphocytes (CTL) by either wheat germ agglutinin or immunoglobulin and evidence of nonspecific target cell killing was sought by the 51Cr-release method. None was found. Thus, merely "gluing" CTL to target cells is not sufficient to effect target cell destruction. In order to determine if the killing mechanisms of CTL, once triggered, would kill adhering nonspecific target cells, CTL with adhering nonspecific target cells were mixed with specific targets. Under these conditions specific target cells were killed but the nonspecific target cells adhering to CTL by virtue of either wheat germ agglutinin or immunoglobulin bridges were not. Thus, when antigen-specific receptors on CTL interact with specific target cell antigens, killing mechanisms are activated in a local restricted manner rather than globally throughout the surface of the CTL.
Isolation of a subset of thymocytes inducible for terminal transferase biosynthesis.
Authors: Cayre Y , de Sostoa A , Silverstone A E
Published: December 2022

A new technique using direct binding of nucleated hematopoietic cells to PNA-coated rabbit red blood cell monolayers was used to separate PNA + and PNA - cells from murine thymus. The rigorously purified PNA - thymocyte population was found to lack TdT and to be low in TL. Incubation of the negative fraction with TP 5 resulted in the synthesis of TdT in a large number of cells in the fraction, and the appearance of TL on the surface of about 20% of the cells. Isolation of this inducible population has led us to propose a new class of cells in intrathymic T cell development.
Epitope-specific antibody feedback regulation of the humoral immune response against sheep erythrocytes in vitro: specific effects of anti-antigen antibody vs nonspecific T cell activities.
Authors: Zubler R H
Published: December 2022

Antibody formed during a 1st in vitro anti-SRBC PFC response had previously been shown to inhibit the formation of PFC when added to a 2nd, freshly established test culture. This effect was to a large extent restricted to test cultures containing B cells sharing VH genes with the B cells producing the initial antibody, and this suggested that anti-SRBC antibody acted via triggering of an anti-idiotypic antibody of TS response. In the present studies this system has been further characterized. First, such antibody feedback occurred in cultures of purified and anti-Lyt2 antiserum and complement-treated surface Ig-positive cells in which TH were substituted for by T-replacing factor. Thus, T cells were not required. Moreover, T cells were always nonspecifically activated in cultures containing FCS. Secondly, anti-idiotypic antibody-like activity was not detected in the sense that generation of inhibitory antibody was never found to be dissociated from generation of anti-SRBC antibody, and LPS-dependent anti-SRBC PFC responses were not inhibited. However, feedback inhibition of SRBC-dependent responses was reversed at increased SRBC concentrations. Thirdly, the feedback mechanism was highly epitope specific, whereas in vitro anti-SRBC PFC responses of different mouse strains (B6 vs BALB/c) were directed to a large extent against different epitopes. These data strongly suggest that VH-restricted inhibitory activity of antibody in this system is a manifestation of epitope specificity of the antibody feedback and not of idiotype specificity, i.e., that anti-SRBC antibody acts via masking of epitopes.
Anti-recipient cytotoxic T lymphocyte precursors are present in the spleens of mice with acute graft versus host disease due to minor histocompatibility antigens.
Authors: Hamilton B L , Bevan M J , Parkman R
Published: December 2022

A model for bone marrow transplantation across minor histocompatibility barriers was developed by using mouse strains that were H-2 identical and mutually non-reactive in MLC. Acute graft-vs-host disease was induced only when donor lymphoid cells were included in the marrow inoculum, in both C57BL/6 recipients of LP cells and BALB/c recipients of B10.D2/nSN cells. GVHD was prevented by treating the lymphoid cells with anti-Thy 1.2 and C before transplantation. Spleen cells from mice with acute GVHD were not directly cytotoxic to recipient strain target cells. However, when spleen cells from mice with GVHD were boosted in vitro to recipient strain stimulator cells they generated a specific anti-recipient cytotoxic response. Spleen cells from mice without GVHD did not generate a cytotoxic response in vitro. The cytotoxic effector cells and their precursors were shown to be T lymphocytes. This model and the in vitro method described may be useful in further studies of the immunobiology of GVHD due to minor histocompatibility antigens and of transplantation tolerance.
MLC-conditioned media stimulate an increase in Fc receptors on human macrophages.
Authors: Guyre P M , Crabtree G R , Bodwell J E , Munck A
Published: December 2022

Macrophage Fc receptors (FcR) are essential for antibody-dependent cellular cytotoxicity and for optimal phagocytosis of opsonized particulate antigens. Culture in the presence of conditioned medium from mixed leukocyte cultures (MLC-CM) resulted in a dose- and time-dependent increase (up to 10-fold) in FcR-dependent binding of 125I-labeled IgG1 to promyelocytic HL-60 cells, macrophage-like U-937 cells, and normal cultured human monocytes. FcR increase in HL-60 cells was blocked by cycloheximide (100 microM) and was accompanied by a slight decrease in binding affinity. Since cell volume did not change, the increase in FcR probably represents an increase in the surface density of FcR sites. MLC-CM prepared with or without serum were equally effective in augmenting FcR sites, whereas only serum-containing MLC-CM caused morphologic change of U-937 and HL-60 cells.
Enhancement of the chemotactic activity of human C5a des Arg by an anionic polypeptide ("cochemotaxin") in normal serum and plasma.
Authors: Perez H D , Goldstein I M , Webster R O , Henson P M
Published: December 2022

The potent chemoattractant, C5a is converted rapidly to C5a des Arg by a carboxypeptidase-like enzyme in normal human serum and plasma. Highly purified human C5a des Arg, at concentrations less than 120 ng/ml, is devoid of chemotactic activity for polymorphonuclear leukocytes. We have found that normal human serum and plasma contain a heat-stable (56 degrees C for 30 min), anionic polypeptide ("cochemotaxin") that permits low concentrations of C5a des Arg (20 to 160 ng/ml) to exhibit significant chemotactic activity. The "cochemotaxin" was isolated from serum and plasma by ammonium sulfate fractionation, molecular sieve chromatography, and anion-exchange chromatography. It was purified by high-performance liquid chromatography and was found to have an Mr of approximately 60,000 (determined by sodium dodecylsulfate polyacrylamide gel electrophoresis). The concentration of "cochemotaxin" in normal serum and plasma was estimated to be 4.0 microgram/ml. Purified "cochemotaxin" acted in a concentration-dependent fashion to permit low concentrations (20 to 160 ng/ml) of C5a des Arg to attract polymorphonuclear leukocytes. Chemotactic activity varied with the input of C5a des Arg and "cochemotaxin" and was maximal when the 2 polypeptides were combined at equal protein concentrations. The profile of chemotactic activity exhibited by C5a des Arg and its "cochemotaxin" very closely resembled that exhibited by dilutions of activated serum and by highly purified C5a. These data suggest that the bulk of chemotactic activity generated in whole serum after complement activation can be accounted for by C5a des Arg and its "cochemotaxin".
Properties of sodium dodecyl sulfate-denatured Interleukin 2.
Authors: Caplan B , Gibbs C , Paetkau V
Published: December 2022

Murine Interleukin 2 (IL2) was denatured with sodium dodecyl sulfate (SDS) with or without concomitant reduction of disulfide bonds. Between 50 and 100% of the activity was recovered upon removal of SDS. When SDS-denatured IL2 was chromatographed on a calibrated gel filtration column in the presence of SDS, it eluted with proteins of m.w. 16,000. This value is supported by sedimentation velocity studies in SDS-containing glycerol gradients. Three activities previously associated with IL2, namely the obligatory role in thymocyte mitogenesis, helper activity in the generation of cytotoxic T lymphocytes, and T cell growth factor activity, co-purified after SDS denaturation. These results indicate that the essential component of murine IL2 is a peptide of m.w. about 16,000. The 3 species of Interleukin 2 studied so far--rat, human, and murine--thus can all exist as polypeptide chains of 15,000 to 16,000 m.w. The murine factor is normally isolated as a larger entity, of about twice this m.w.
Detection of the dominant expression of the TEPC-15 idiotypic determinant(s) on phosphorylcholine-specific suppressor T lymphocytes in vitro.
Authors: Kohmo T , Yamamoto H , Mizuochi T , Hamaoka T
Published: December 2022

Phosphorylcholine-(PC) specific suppressor T lymphocytes, induced by immunization with PC-coupled syngeneic spleen cells and capable of suppressing antibody production in an in vitro system, were successfully obtained by removal of a PC-nonspecific, i.e., diazo-phenylstructure-directed, suppressor cell population using an immunoadsorbent column coupling an unrelated hapten with a diazo phenyl structure such as azobenzene arsonate (ABA). Column-purified PC-specific suppressor T cell activity was completely abrogated by treatment of the cells with anti-TEPC-15 (T-15) anti-idiotypic antibody and complement, or by the continuous presence of that antibody in the culture, whereas nonpurified suppressor cell activity was resistant to such treatment. Thus, the column-purified PC-specific suppressor T lymphocytes in BALB/c mice have a very homogeneous T-15 idiotypic determinant(s) on their functional receptors for antigen similar to those present on PC-specific antibody and/or B lymphocytes. Because of these results, we envision the growing importance of analysis of the fine specificity of the idiotype repertoire of T lymphocytes after purification of a hapten-specific population.
Increased peripheral blood monocytes with Fc receptors for IgE in patients with severe allergic disorders.
Authors: Melewicz F M , Zeiger R S , Mellon M H , O'Connor R D , Spiegelberg H L
Published: December 2022

Peripheral blood monocytes, defined as latex bead-ingesting mononuclear cells, from 15 healthy nonallergic donors and 22 patients with allergic disorders were analyzed for Fc receptors for IgE (Fc epsilon) by a rosette assay employing ox erythrocytes coated with IgE. The patients were divided into 3 groups. Group I: 12 patients with mild to moderate atopic disease and serum IgE levels up to 2300 IU/ml. Group II: 6 patients with severe generalized atopic dermatitis, allergic rhinitis, and asthma, of which 5 had IgE serum levels of 8000 to 77,500 IU/ml. Group III: 4 severely atopic patients with IgE levels greater than 10,000 IU/ml and receiving oral corticosteroids. The numbers of monocytes were similar in healthy donors and patients. In contrast, severely atopic patients (Group II) had significantly more (p less than 0.01) Fc epsilon + monocytes (107 +/- 42/mm3) than healthy donors (20 +/- 14/mm3) or patients of Group I (31 +/- 14/mm3). Patients of Group III had significantly fewer (p less than 0.05) Fc epsilon + monocytes (12 +/- 16/mm3) than controls and patients of Groups I and II. We conclude that patients with severe allergic disorders have a significant increase of peripheral blood monocytes with Fc receptors for IgE, which suggests that these cells may participate in the pathophysiology of atopic disease.
Nature of double-stranded DNA binding activity in seropositive rheumatoid arthritis: formation of low avidity DNA/rheumatoid factor/IgG/low density lipoprotein complexes.
Authors: Winfield J B , Shaw M , Taylor R P , Eisenberg R A
Published: December 2022

Sera from majority of patients with seropositive rheumatoid arthritis, which generally lacked detectable anti-double stranded DNA in Farr, Crithidia luciliae, and microcomplement fixation assays, exhibited high levels of dsDNA binding in the presence of 3.5% polyethylene glycol when using intrinsically labeled 3H-PM2 DNA as antigen. Except for SLE, such increased dsDNA binding was absent in normal and a variety of other disease sera, including those from patients with seronegative rheumatoid arthritis. In contrast to the situation in SLE, in which dsDNA binding is mediated by specific anti-DNA antibody, the increased dsDNA binding activity in seropositive rheumatoid arthritis was shown to be dependent upon complex low avidity interactions involving DNA, IgG, IgM rheumatoid factor, and low density lipoproteins. Analysis of the composition of the polyethylene glycol serum precipitates by 2-dimensional gel diffusion, immunoelectrophoresis, and sodium dodecyl sulfate polyacrylamide gel electrophoresis failed to reveal the presence of additional DNA-binding proteins unique to seropositive rheumatoid arthritis. The only feature distinguishing high DNA binding sera from those with low DNA binding activity was an increased amount of polyethylene glycol-insoluble IgG in the former, presumably reflecting IgG/IgG and/or IgG/IgM complexes. The significance of these unusual DNA/low density lipoprotein/IgG/rheumatoid factor complexes with respect to the diagnostic specificity and pathophysiology of the DNA/anti-DNA system is discussed.
Glucocorticoid receptor content of T lymphocytes: evidence for heterogeneity.
Authors: Distelhorst C W , Benutto B M
Published: December 2022

Glucocorticoid receptors were measured in T lymphocytes that were isolated from peripheral blood by either nylon wool filtration or E-rosette sedimentation. T cells isolated by nylon wool filtration specifically bind 6.7 +/- 0.2 fmol of dexamethasone per million cells (equivalent to 4000 +/- 200 receptors per cell), whereas T cells isolated by E-rosette sedimentation bind 12.0 +/- 0.7 fmol of dexamethasone per million cells (equivalent to 7200 +/- 400 receptors per cell). This difference in the amount of dexamethasone bound by the two T cell preparations was significant (p less than .001) and was present immediately after cell isolation. The binding affinities of the different T cell preparations for dexamethasone were similar. T cells that are isolated by a combination of nylon wool filtration followed by E-rosette sedimentation bind the same amount of dexamethasone as T cells isolated by nylon wool filtration alone. T cells isolated by a combination of E-rosette sedimentation following by nylon wool filtration bind less dexamethasone than do T cells isolated by E-rosette sedimentation alone. These findings suggest that T cells are heterogeneous with respect to their quantity of glucocorticoid receptors. Isolation of T cells by E-rosette sedimentation enriches for T cells that have a greater number of glucocorticoid receptors, and isolation of T cells by nylon wool filtration enriches for T cells that have a lesser number of glucocorticoid receptors.
Thymidine transport in human lymphocytes stimulated with concanavalin A: effect of colchicine.
Authors: Rudd C E , Kaplan J G
Published: December 2022

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.
Immunoglobulin heavy chains from anti-inulin myeloma proteins: evidence for a new heavy chain joining segment.
Authors: Rudikoff S , Potter M
Published: December 2022

Immunoglobulin heavy chains have been shown to be encoded by at least 3 widely separated genetic elements, designated variable (V), diversity (D), and joining (J), which undergo rearrangement during somatic differentiation to produce the active gene form. The D segment codes for a portion of the 3rd hypervariable region and thus potentially contributes significantly to structural diversity in this portion of the molecule. Heavy chains from anti-inulin proteins are unusual in that they essentially lack a 3rd hypervariable region. Thus, if a D segment exists in these proteins, it is extremely short, possibly 1 to 2 amino acids, and more likely serves a framework function rather than introduces structural diversity in the 3rd hypervariable region. We have completed the heavy chain variable region amino acid sequence from proteins AMPC1 and T957 bringing to 6 the number of complete sequences from this group. All of these proteins lack a 3rd hypervariable region. In addition, substitutions are found within the J segments of AMPC1 and T957, which are unlikely to be generated by the recombination event. The occurrence of Pro at position 105 in both of these J segments in contrast to the Gln found in all other heavy chains using this J segment suggests the possible existence of a previously unidentified J segment gene.
In vivo effects of anti-asialo GM1. I. Reduction of NK activity and enhancement of transplanted tumor growth in nude mice.
Authors: Habu S , Fukui H , Shimamura K , Kasai M , Nagai Y , Okumura K , Tamaoki N
Published: December 2022

Intravenous injection of anti-asialo GM1, which has been shown to eliminate natural killer (NK) activity in vitro in the presence of complement, completely abolished NK activity against lymphoma cell line (YAC-1) in spleen cells from athymic nude mice as well as from conventional mice. An immunofluorescence study revealed a decreased number of asialo GM1 positive cells in the spleens of mice injected with anti-asialo GM1 than in those of mice injected with normal rabbit serum. In the nude mice with reduced NK activity, incidence of tumor take and the growth were enhanced when syngeneic (RL male-1), and allogeneic (YAC-1) tumors and human tumors were transplanted subcutaneously. These results strongly suggest that NK cells play an important role in transplanted-tumor growth in vivo.
The membrane attack mechanism of complement: photolabeling reveals insertion of terminal proteins into target membrane.
Authors: Hu V W , Esser A F , Podack E R , Wisnieski B J
Published: December 2022

We have utilized a membrane-restricted, photoactivable glycolipid probe to investigate the protein-lipid interactions involved in complement (C) mediated lysis of a target membrane. The purified C proteins C5b-6, C7, C8, and C9 were added to artificial membrane vesicles containing the 14C-labeled photoreactive probe anchored in the outer monolayer of the membrane, and 6-carboxyfluorescein trapped in the lumen as an indicator for effective lysis. Irradiation of the membrane samples at different stages of functional complex assembly resulted in labeling of each of the 5 terminal C proteins, indicating that all 5 proteins become inserted into the hydrophobic milieu of the membrane during some stage of complex assembly. However, at the final stage of complex assembly, only C9 appeared to be labeled. Because we can demonstrate that the photoreactive probe has no strong affinity for C9 over the other terminal components (C5b-C8), the extensive change in labeling specificity during assembly is evidence for substantial changes in protein-lipid and possibly protein-protein interactions during formation of the C lesion.