bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing effects of monocytes on modulation of a lymphocyte membrane antigen.
Authors: Schroff R W , Klein R A , Farrell M M , Stevenson H C
Published: December 2022

Redistribution, or modulation, of some cell surface antigens occurs in the presence of specific antibody. The phenomenon of antigenic modulation may therefore affect the use of antibodies as therapeutic agents. This study was undertaken to investigate modulation of the 65,000 dalton T65 antigen, present on normal and malignant T cells and some malignant B cells, which is recognized by the monoclonal antibody T101. To induce cell surface antigenic modulation, normal or leukemic lymphoid cells were cultured in the presence of monoclonal antibody T101 for 3-hr periods. Removal of monocytes from mononuclear cell preparations resulted in significantly lower degrees of T65 antigenic modulation. The degree of antigenic modulation could be increased by adding monocytes back to monocyte-depleted lymphocyte suspensions. Furthermore, maximal modulation occurred in the presence of monocytes at T101 concentrations that were 3 logs lower than in the absence of monocytes. The enhancing effect of monocytes was dependent on the Fc portion of the T101 antibody molecule, and presumably was mediated by cross-linking of antigen-antibody complexes on the surface membrane of the modulating cell by Fc receptors present on monocytes. Further experiments performed to examine the characteristics of this enhancement of antigenic modulation by monocytes indicated that autologous as well as allogeneic monocytes were effective, indicating that the enhancing phenomenon was not dependent upon recognition of major histocompatibility antigens. Viable monocytes were required, but pretreatment of monocytes with sodium azide to inhibit energy production, or indomethacin to inhibit prostaglandin synthesis had no effect on this phenomenon. Polymorphonuclear leukocytes did not mediate similar enhancement, although monocytic and myeloid cell lines U937, THP-1, and HL-60 did. Spent culture medium from modulated cultures and preparations containing IL 1 activity did not enhance modulation of the T65 surface antigen on lymphocytes, suggesting that direct contact between lymphocytes and monocytes is required to mediate the effect. The finding that leukemic cells from patients with CLL undergo modulation of the T65 antigen to a much lower degree in vitro than observed in vivo, and that this difference can be overcome by the addition of monocytes, suggests that monocytes or the reticuloendothelial system may augment antigenic modulation in vivo.
B cell repertoire diversity to PR8 influenza virus does not decrease with age.
Authors: Zharhary D , Klinman N R
Published: December 2022

The affect of aging on the B cell repertoire was investigated at the clonal level by studying the response of 24- to 26-mo-old BALB/c mice to the PR8 influenza virus (H1N1). By using the splenic fragment culture technique, it was found that the frequency of B cells specific for either the intact virion or the HA does not change with age. The anti-HA monoclonal antibodies obtained from culture were additionally analyzed for fine specificity by binding in RIA to a panel of six H1 variant viruses. This analysis showed a considerable similarity in the distribution and diversity of reactivity patterns between monoclonal antibodies derived from splenic B cells of young vs aged mice. These findings indicate that repertoire expression per se may not be truncated in aged mice, and imply that reductions in the diversity of serum antibodies in aged mice may be due to environmental regulatory mechanisms.
In vitro regulation of IgA subclass synthesis. II. The source of IgA2 plasma cells.
Authors: Conley M E , Bartelt M S
Published: December 2022

In vitro regulation of IgA subclass synthesis was investigated in pokeweed mitogen (PWM)-stimulated cultures of peripheral blood lymphocytes. In past experiments we have demonstrated that 50% of the IgA plasma cells derived from PWM-stimulated cultures are positive for IgA1 and 50% are positive for IgA2. This observation is surprising because approximately 80% of the IgA B cells in the peripheral circulation bear IgA1 and 20% bear IgA2. To determine if the shift toward IgA2 predominance in PWM-stimulated cultures might be due to an enriched source for IgA2 plasma cells from a precursor pool of immature B cells, we used panning techniques to separate immature precursors that express surface IgM (sIgM+) from mature precursors that no longer express IgM (sIgM-). These separated B cells were cultured with equal numbers of T cells and PWM for 7 days. In all 10 experiments there was an enrichment for IgA2 in the sIgM+ cultures; 55 +/- 9.6% of the total IgA plasma cells were positive for IgA2 in the sIgM+ cultures vs 38 +/- 6.3% in the sIgM- cultures (p less than 0.001). These results indicate that both sIgM+ and sIgM- cells can give rise to IgA plasma cells in PWM-stimulated cultures and that there is an enrichment for IgA2 precursors in the sIgM+ population. Other possible regulatory mechanisms were also investigated. To determine if there was isotype switching from IgA1 to IgA2, monoclonal anti-IgA1 antibodies were added to PWM cultures. These antibodies resulted in a mean suppression of IgA1 plasma cell production of 82% with a concomitant 45% suppression of total IgA but only 4.6% suppression of IgA2. These results make it unlikely that IgA2 plasma cells in PWM-stimulated cultures are derived from cells that initially produced IgA1. To investigate the possibility that one IgA subclass might be more T cell dependent than the other, T and B cells were separated and B cells were reconstituted with T cells in ratios that varied from 1:10 to 10:1 or with irradiated T cells. These procedures did not alter the proportion of IgA plasma cells positive for IgA1 or IgA2, indicating that the two subclasses do not differ in their response to T cell signals in PWM-stimulated cultures.
Temperature-mediated processes in teleost immunity: differential effects of temperature on catfish in vitro antibody responses to thymus-dependent and thymus-independent antigens.
Authors: Miller N W , Clem L W
Published: December 2022

An in vitro culture system was employed to ascertain the effects of different temperatures on the anti-hapten antibody-secreting cell responses of channel catfish leucocytes to murine thymus-dependent (TD) and thymus-independent (TI) antigens. The magnitudes of primary responses to a TI antigen (TNP-LPS) and secondary responses to a TD antigen (DNP-KLH) were relatively independent of in vitro culture temperature. The kinetics of each of these responses as a function of temperature was characterized by a Q10 of 2. In contrast, the magnitudes of primary responses to TD antigens (DNP-KLH and DNP-HoSA) were suppressed at lower in vitro temperatures. Furthermore, it was observed that some of the low temperature suppression of primary responses to TD antigens could be abrogated by appropriate low temperature in vivo acclimation. These findings are interpreted as supporting the hypothesis that low environmental temperatures immunosuppress fish by virtue of differential inhibitory effects on the generation of carrier-specific helper cells.
A novel anti-Ia monoclonal antibody which specifically enhances the corresponding T cell alloreactivity.
Authors: Kimura A K , Peck A B
Published: December 2022

An anti-I-Ab monoclonal antibody, designated K14.83-11, was produced in a fusion between SP 2/0 Ag-14 myeloma cells and spleen cells from a B10.D2/n mouse primed in vivo against C57BL/10. Unlike other anti-I-Ab monoclonal antibodies thus far described, K14.83-11 was found to have a combination of features involving specificity, isotype, and function, unique among existing anti-I-A reagents. K14.83-11 exhibited a strong binding to the I-Ab gene product, with only slight cross-reactivity to the I-Ap/q family of allelic products and no reactivity towards I-Ak,d. When analyzed for isotype, K14.83-11 was found to be of a rare IgG3 isotype. With respect to biologic activity, K14.83-11 not only failed to produce the expected inhibition of specific anti-I-Ab T cell reactivity in vitro, but instead produced a striking enhancement of T cell responses against the I-Ab gene product. The possible relationship of IgG isotype and function was suggested when the immunoenhancing effect of K14.83-11 on reactive T lymphocytes was reversed to that of suppression with highly purified F(ab)2 fragments obtained by pepsin digestion.
Memory CTL-hybridoma: a model system to analyze the anamnestic response of cytolytic T lymphocytes.
Authors: Moscovitch M , Kaufmann Y , Berke G
Published: December 2022

We have previously described monoclonal CTL-hybridomas growing continuously in culture in the absence of a known antigenic stimulus or growth-promoting factor(s), exhibiting specific anti-H-2Db killing activity in vitro after a distinct 2-hr lag period before the onset of lysis. Here we provide evidence indicating that the hybridoma Md 26.15 represents "memory" CTL, and we examine the mechanism whereby they respond to antigen/mitogen. The brief period (2 to 3 hr) required for stimulation suggests that expression of potentiated effector function(s) after stimulation requires no cell replication. The frequency of effector hybridoma cells capable of specific binding to target cells before and after stimulation is the same, as determined in a direct hybridoma-target cell conjugation test, although cytolytic activity is markedly enhanced. On the other hand, kinetic and cell dispersion assays indicate that the potentiation of cytolytic activity can be attributed to shortening of the lag period of killing as well as to a small enhancement in the recycling ability of cytolytic effectors. We suggest that shortening of the lag period involves activation of potential effectors, which is manifested at a post-binding stage of effector-target interaction. The CTL hybridoma described herein provides a unique model system for studying CTL reactivation.
Characterization of two different Ly-1+ T cell populations that mediate delayed-type hypersensitivity.
Authors: Van Loveren H , Kato K , Meade R , Green D R , Horowitz M , Ptak W , Askenase P W
Published: December 2022

This paper describes two functionally different T cell populations that mediate delayed-type hypersensitivity (DTH) reactions in contact-sensitized mice. Both of these T cells are Ly-1+, Qa-2-, and Vicia villosa lectin nonadherent. One of these T cell subpopulations is responsible for the classical 24- to 48-hr component of DTH reactions, is induced 3 to 4 days after immunization, is H-2 restricted, is sensitive to irradiation and to antigen-specific T cell-derived suppressor factors, and is found in nylon wool-nonadherent as well as nylon wool-adherent populations. In contrast, the T cell population that is responsible, via an antigen-specific T cell factor, for a recently described early component of DTH, which is an obligatory initial step for expression of DTH, is induced within 24 hr after immunization, requires much less antigen for immunization, is not H-2 restricted, is not sensitive to irradiation nor to T suppressor factors, and is found exclusively in the nylon wool-nonadherent fraction. These results support a new formulation of DTH. According to this formulation, Ly-1+ T cells produce an antigen-specific, tissue-sensitizing, mast cell-activating factor, and via this factor induce the early component of DTH, which is an obligatory first step in which local antigen challenge induces increased local vascular permeability. This required opening of gaps between endothelial cells is due to T cell factor-dependent release of the vasoactive amine serotonin from cells such as mast cells. This first step allows the second, H-2-restricted, Ly-1+ T cell population to enter the reaction site, and to then be triggered by antigen to release lymphokines that attract the subsequent influx of blood-borne, bone marrow-derived leukocytes to constitute the classical delayed-in-time component of DTH reactions.
Stimulation of immunoglobulin secretion in human B lymphocytes as a direct effect of high concentrations of IL 2.
Authors: Ralph P , Jeong G , Welte K , Mertelsmann R , Rabin H , Henderson L E , Souza L M , Boone T C , Robb R J
Published: December 2022

In certain human IgM and IgG cell lines, immunoglobulin (Ig) secretion is highly stimulated by a B cell inducing factor (BIF) that is free of interleukin 2 (IL 2). BIF also induces Ig secretion in purified peripheral blood B cell populations that have been mitogenically stimulated by Staphylococcus aureus bacteria. Low concentrations of IL 2 (less than 20 U/ml) are not active in these systems. We now show that IL 2 at concentrations above 100 U/ml can induce Ig secretion in these blood B cells and B cell lines. Both conventional IL 2, purified from the human JURKAT and gibbon MLA-144 cell lines, and recombinant IL 2 are active. Very high concentrations approaching 10(4) U/ml are optimal for Ig secretion. Antibody to the T cell IL 2 receptor, anti-Tac, did not inhibit stimulation of the IgM cell line SKW6.4 by IL 2, and no Tac antigen was detected on the cells. The 9B11 monoclonal anti-IL 2 antibody that neutralizes T cell growth activity also abrogates stimulation of Ig secretion by conventional and recombinant IL 2 in the SKW6.4 cell line. However, the 1H11 monoclonal anti-(conventional thr3-glycosylated IL 2), which does not neutralize T cell growth activity, does inhibit induction of Ig secretion by the corresponding IL 2 in the B cell line. These results suggest that IL 2 stimulates B cells via a low-affinity interaction with a receptor different from the Tac receptor identified on T cells, and that the active site on the IL 2 molecule for B cells differs from that for T cell targets. If IL 2 promotes Ig secretion by binding with a low affinity to the B cell BIF receptor, IL 2 and BIF could be homologous proteins.
Demonstration of auto-anti-idiotypic antibody cross-reacting with public idiotypic determinants in the serum of rye-sensitive allergic patients.
Authors: Bose R , Marsh D G , Duchateau J , Sehon A H , Delespesse G
Published: December 2022

The present study documents the presence, in the serum of one allergic individual, of auto-anti-idiotypic antibodies cross-reacting with public idiotypic determinants expressed on human IgE and IgG anti-Rye I antibodies. Sera from rye-sensitive patients were tested for specific IgG and IgE antibodies to Rye I by double antibody. The IgG fraction, isolated from the serum of a patient with a history of previous hyposensitization therapy, was repeatedly absorbed on Rye-I-Sepharose as well as on IgM- and IgG-Sepharose to remove anti-Rye I antibodies as well as any possible anti-heavy or light chain activity. This IgG fraction, named anti-idiotypic fraction (a-IdF), blocked in a dose-dependent fashion the reaction of IgG and IgE anti-Rye I antibodies with Rye I antigen. The a-IdF also blocked the binding of anti-rye antibodies to Rye I antigen in the serum of 20 unrelated allergic patients, indicating that these anti-Rye I antibodies bore public idiotypic determinants.
Induction of T cell aggregation by antibody to a 16kd human leukocyte surface antigen.
Authors: Chen Y X , Welte K , Gebhard D H , Evans R L
Published: December 2022

We describe studies of a human leukocyte antigen, termed Leu-13, that is defined by a mouse monoclonal antibody that reacts with T and B lymphocytes. Optimal staining of T cells requires a much higher concentration of alpha Leu-13 (greater than or equal to 200 micrograms/ml) than alpha Leu-4 (6 micrograms/ml). However, the fluorescence intensity of T cells labeled with alpha Leu-13, washed and kept at 4 degrees C for different periods, does not diminish more rapidly than the fluorescence of T cells stained with alpha Leu-4 and treated the same way. These results indicate that the novel binding pattern of alpha Leu-13 is not due to weak affinity. Immunoprecipitation and SDS-PAGE analysis indicates that alpha Leu-13 precipitates a major 16-kilodalton (16kd) band and a minor 26kd component from Nonidet P-40-solubilized membrane of normal T cells that are surface-labeled with 125I. The similar sizes of the 16kd to 26kd (Leu-13) and 22kd to 28kd (Leu-4) molecules prompted us to compare the capacity of alpha Leu-13 and alpha Leu-4 to trigger T cell functions, and to co-modulate and co-precipitate the T cell antigen receptor. Unlike alpha Leu-4, alpha Leu-13 does not trigger T cell proliferation or augment NK activity, but inhibits the mitogenic effect of alpha Leu-4/T3 antibodies. alpha Leu-13 also induces T cells to clump into large aggregates after 16 hr of culture at 37 degrees C, but not at 4 degrees C. T cell aggregation is triggered by concentrations of alpha Leu-13 as low as 12.5 ng/ml. At this concentration, alpha Leu-13 is not detectable on the surface of T cells by indirect immunofluorescence analysis in a FACS. On leukemic T cells, alpha Leu-4 was found to co-modulate and co-precipitate a 38kd to 44kd dimer having apparent idiotypic determinants, whereas alpha Leu-13 did not. The possible significance of these findings to immune regulation by T cells is discussed.
Specificity of human IgM M-proteins that bind to myelin-associated glycoprotein: peptide mapping, deglycosylation, and competitive binding studies.
Authors: Shy M E , Vietorisz T , Nobile-Orazio E , Latov N
Published: December 2022

Ten patients with neuropathy and IgM M-proteins that bind to the myelin-associated glycoprotein (MAG) were studied to determine whether the M-proteins bind to common regions of MAG and whether the reactive determinants contain carbohydrate residues. The M-protein of one patient was biotinylated, and binding to human MAG was quantitated by enzyme-linked immunosorbent assay (ELISA) by using avidin-biotin-peroxidase complexes. Serum from the same patient and nine others, but not from controls, competed with the biotinylated M-protein for binding to human MAG. Bovine MAG was digested with staph protease or cleaved with cyanogen bromide, and the resultant fragments were separated by electrophoresis and were transferred onto nitrocellulose sheets. Serum from all patients immunostained the peptide fragments identically. Bovine MAG was deglycosylated by trifluoromethanesulfonic acid, and binding of the M-proteins to MAG and to deglycosylated MAG was tested by immunoblotting. None of the patient's M-proteins bound to deglycosylated MAG. Deglycosylated MAG was visualized by using a mouse monoclonal antibody, GEN-S3, directed at the polypeptide core of MAG. The effectiveness of deglycosylation was ascertained by electrophoresis and by binding of biotinylated concanavalin A. These data and the observed identical species specificity of the M-proteins suggest that the respective anti-MAG M-proteins all bind to the same region in MAG and that the reactive determinants may contain carbohydrate moieties.
Phenotype and function of engrafted maternal T cells in patients with severe combined immunodeficiency.
Authors: Thompson L F , O'Connor R D , Bastian J F
Published: December 2022

Engrafted maternal T cells from two patients with severe combined immunodeficiency (SCID) and graft-vs-host disease (GVHD) were characterized for surface phenotype, function, and ecto-5'-nucleotidase (ecto-5'-NT) activity. The majority of engrafted T cells from both patients were T6-, T3+, and Ia+; the ratio of T4+:T8+ cells varied from 0.89 to 3.1 for Patient 1 and was 0.17 for Patient 2. The sum of T4+ + T8+ cells was greater than the number of T3+ cells, and approximately one-third of the patients' T cells were T3-. Two-color immunofluorescent staining showed that one-third of the T cells from Patient 1 had a novel cell surface phenotype (T6-, T3-, T4+, T8+) that was not previously described. T cells from Patient 1 failed to proliferate in response to allogeneic cells or specific antigen and provided little help for PWM-driven Ig synthesis in vitro. However, they did suppress Ig synthesis in vitro and proliferate in response to PHA and Con A; thus they appeared to be more mature than the T cells of Patient 2 and of most previously reported patients with SCID and maternal T cell grafts. Both patients lacked detectable lymphocyte ecto-5'-NT activity, suggesting that either the ecto-5'-NT activity of maternal T cells is lost after engraftment or that a specific subset(s) of ecto-5'-NT-negative maternal T cells predominates in infants with SCID and GVHD. Thus, in vitro T cell function and the proportions of T cells bearing T4 and T8 may vary in SCID patients with maternal T cell grafts. However, the presence of the Ia antigen and the absence of ecto-5'-NT activity may be consistent features of activated maternal T cells responsible for GVHD.
Defective mononuclear phagocyte function in systemic lupus erythematosus: dissociation of Fc receptor-ligand binding and internalization.
Authors: Salmon J E , Kimberly R P , Gibofsky A , Fotino M
Published: December 2022

Fc receptor-mediated mononuclear phagocyte system (MPS) clearance is impaired in systemic lupus erythematosus (SLE) and may contribute to the pathogenesis of the immune complex disease. To investigate the basis of MPS dysfunction, we have examined concurrent in vivo and in vitro Fc receptor function in 22 patients with SLE and 23 disease-free adults. Blood monocyte Fc receptor binding was increased rather than decreased as predicted by the saturation hypothesis of MPS blockade. Rosette formation of IgG-sensitized bovine erythrocytes (EA) with monocytes demonstrated increased Fc receptor-ligand binding in SLE (percent rosettes: 40 +/- 12 vs 27 +/- 8, p less than 0.001). Scatchard analysis of the binding of radiolabeled IgG oligomers to SLE monocytes indicated a mean receptor number 30% higher than control, although this did not reach statistical significance. Despite enhanced Fc receptor-ligand (EA) binding, Fc-mediated phagocytosis of EA was decreased in SLE (1.7 +/- 0.7 erythrocytes/monocytes/hour vs 2.6 +/- 1.0, p less than 0.004). This decrease in phagocytosis by blood monocytes from SLE patients was significantly greater than that attributable to the predominance in SLE of individuals with certain HLA B cell alloantigens and intrinsically lower phagocytic rates (p less than 0.05 for all groups). This decrease therefore represents a disease-acquired characteristic. Furthermore, the phagocytic rate of the four SLE patients with marked prolongation in MPS clearance was significantly lower than that of the eight patients with near normal clearance values (p less than 0.01). Saturation of Fc receptors by immune complexes does not explain impaired immune clearance in SLE. Our results indicate that despite increased binding of the EA ligand, Fc receptor-mediated phagocytosis is markedly impaired in SLE monocytes. This impairment cannot be explained on the basis of HLA-related differences in phagocytosis among lupus patients. The defect in phagocytosis of EA is most profound in those patients with the most significantly impaired MPS clearance. Thus, the dissociation of receptor-ligand binding and receptor-mediated internalization may contribute significantly to the in vivo clearance defect in SLE.
T cells from autoimmune "IL 2-defective" MRL-lpr/lpr mice continue to grow in vitro and produce IL 2 constitutively.
Authors: Rosenberg Y J , Steinberg A D , Santoro T J
Published: December 2022

MRL-lpr/lpr mice and other autoimmune strains that bear the lpr gene develop a profound lymphadenopathy characterized by an expansion of a unique dull Lyt-1+2- T cell population. Because fresh splenic and lymph node T cells from such mice stimulated Con A in vitro are extremely defective in IL 2 production and proliferation, T cell lines derived from MRL-lpr/lpr spleens were established and maintained for several months, and were analyzed for their factor production to define their growth requirements. The results indicate that cultivation in vitro leads to constitutive production of IL 2 and the capacity to respond to growth factors, thereby facilitating the continuous proliferation of T cells bearing the dull Lyt-1+2- phenotype in vitro in the absence of exogenous antigen or mitogen. These studies indicate that MRL-lpr/lpr T cells have the ability to produce IL 2 and to respond to IL 2 with long-term proliferation. In addition, the impaired responsiveness to Con A of fresh MRL-lpr/lpr lymph node T cells was found to be quite transitory, because even short-term culture allowed MRL lpr/lpr T cells to respond normally.
Mitogenic properties of neuraminidase and galactose oxidase-treated lymphoblastoid cells and plasma membranes for peripheral blood lymphocytes.
Authors: Arnold A , Rubin A L , Novogrodsky A , Stenzel K H
Published: December 2022

Generation of aldehydes on terminal D-galactose or N-acetyl-D-galactosamine residues of cell surface glycoproteins by treatment with neuraminidase and galactose oxidase (NAGO) renders some types of cells mitogenic for T lymphocytes. The cell surface molecules required for the presentation of mitogenic signals by NAGO-treated cells are unknown. We tested the mitogenic properties of NAGO-treated lymphoblastoid cell lines (LCL) and subcellular fractions as an initial step in the isolation and characterization of cell surface molecules required for stimulation. We report here that the NAGO-LCL of B cell lineage were potent stimulators, whereas the NAGO-LCL of T cell lineage were weaker and more variable stimulators of lymphocyte proliferation. T-LCL that were stimulatory in indirect stimulation did not induce a mixed lymphocyte response, whereas the B-LCL were positive in both assays. Aldehyde-bearing plasma membrane-enriched subcellular fractions, depleted of nuclear, cytosolic, and mitochondrial components, were mitogenic, and the stimulatory activity was dose dependent. The ability to induce mitogenesis was abrogated by reduction of cell surface aldehyde groups. The results indicate that lymphocyte activation, induced by NAGO-treated stimulatory cells, is a plasma membrane-associated event and does not require the metabolic activity of intact cells. Furthermore, the aldehyde moiety is required but not sufficient for presentation of mitogenic signals. The LCL provide a suitable and reproducible source for isolation and characterization of stimulatory cell surface structures.
Naturally occurring autoantibodies to exoplasmic and cryptic regions of band 3 protein, the major integral membrane protein of human red blood cells.
Authors: Lutz H U , Flepp R , Stringaro-Wipf G
Published: December 2022

Immunoglobulin G (IgG) of healthy human blood donors and IgG from pooled sera (Sandoglobulin) contain natural (auto)antibodies to band 3 protein, the major integral membrane protein of human red blood cells. Affinity-purified and 125I-iodinated anti-band 3 antibodies bound specifically to band 3 protein on immunoblots from membrane proteins in the presence of unlabeled, absorbed IgG. Purified (auto)antibodies also bound nonspecifically to band 4.2 and weakly to band 5 and 6, when assayed with second antibody and 125I-iodinated protein A. The antibodies were directed to regions of band 3 protein that were cryptic and in part exoplasmic but with a low accessibility to surface modifications. The antigenic sites were located within the 65K, but not the 38K-dalton chymotryptic fragment of band 3 protein. Antigenic band 3 protein was equally present in membranes of young and senescent red cells. Hence, if these antibodies were involved in recognizing a few exoplasmic sites of band 3 protein on senescent red cells, antigen exposure would require alterations in band 3 accessibility (conformation, topology) rather than an enzymatic generation of antigenic sites.
Antigenic complexity of Treponema pallidum: antigenicity and surface localization of major polypeptides.
Authors: Norris S J , Sell S
Published: December 2022

The protein structure of Treponema pallidum was characterized by two-dimensional electrophoresis (2DE), consisting of isoelectric focusing (IEF, pH 5 to 7) in the first dimension and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the second dimension. Up to 85 major polypeptide species could be detected in the organisms in 2DE gels by Coomassie Blue staining. The antigenicity of the individual polypeptides was determined by transferring the 2DE pattern to nitrocellulose paper and utilizing a sensitive immunoperoxidase procedure to demonstrate the reactivity of immunoglobulins in sera obtained from rabbits infected intratesticularly at least 6 mo previously. The infected rabbit serum reacted with virtually every major polypeptide detectable by protein staining techniques, indicating that infected rabbits produce antibodies against nearly all major T. pallidum proteins at the time when the animals exhibit systemic resistance to reinfection. Surface radioiodination of freshly purified T. pallidum by an Iodogen procedure yielded preferential labeling of a major polypeptide with an apparent m.w. of 39,000. The results of this study indicate that the antigenic complexity of T. pallidum is much greater than described previously. The 39-kd polypeptide appears to be a major surface constituent of T. pallidum and as such may play an important role in the induction of immunity to syphilis.
Amino acid sequence diversity in mouse lambda 2 variable regions.
Authors: Elliott B W , Eisen H N , Steiner L A
Published: December 2022

The lambda-chains of immunoglobulins from BALB/c mice constitute the simplest system presently available for studying patterns of variable-region diversity. The limited number of V lambda and J lambda germ-line gene segments facilitates comparison of expressed and germ-line sequences. We report here the complete amino acid sequence of the variable regions of three lambda 2 chains and of one chain representing a V lambda 2----J lambda 3 rearrangement. Together with the previously determined sequence of the lambda 2 chain from myeloma MOPC-315, the results illustrate the following types of variable-region diversification: expression of a single V gene segment with more than one J segment, variability at the V-J junction, and presumably, somatic mutation in V and in J. The extent of somatic diversification in these lambda 2 chains is limited, consistent with results obtained previously with lambda 1 chains.
Mechanisms in the suppression of tumor rejection produced in mice by repeated UV irradiation.
Authors: Ullrich S E , Kripke M L
Published: December 2022

Mice exposed repeatedly to UVB (280 to 320 nm) radiation are unable to reject highly antigenic UVB-induced skin cancers, and their lymphoid organs contain T lymphocytes that transfer this inability to nonimmune recipients. We show that the phenotype of the cells capable of transferring suppression of tumor rejection is Lyt-1+2-,Ia-. Removal of the suppressive activity of spleen cells from UVB-irradiated mice through the use of monoclonal anti-Lyt-1 antibodies resulted in a population of cells capable of mediating tumor rejection when injected into lethally x-irradiated recipients. This finding demonstrates that the inability of UVB-irradiated mice to reject skin cancers induced by UVB radiation is not due to clonal deletion, e.g., the absence of lymphocytes that are capable of recognizing and responding to antigens on these tumors, but instead is likely to depend solely on the activity of suppressor lymphocytes. The phenotype of antigen-specific suppressor lymphocytes induced by painting oxazalone on the unirradiated skin of mice exposed once to UVB radiation was Lyt-1+2-, also a finding consistent with the hypothesis that the two forms of UVB-induced immunosuppression occur by means of the same mechanism. The phenotype of suppressor cells induced in mice treated once with 8-methoxypsoralen plus UVA (320 to 400 nm) radiation, followed by painting unexposed skin with oxazalone, was Lyt-1+2+, suggesting that this treatment may activate a different suppressor pathway.
In vitro propagation and cloning of murine natural suppressor (NS) cells.
Authors: Hertel-Wulff B , Okada S , Oseroff A , Strober S
Published: December 2022

During a short period of time after birth or after radiotherapy, the spleens of neonatal and adult TLI-treated mice contain suppressor cells of the mixed leukocyte reaction (MLR) and of graft-vs-host disease. The present report shows that the MLR suppressive activity of spleen cells from TLI-treated adult BALB/c mice can be maintained in long-term tissue culture by using conditioned medium. The suppressor cells can be cloned by limiting dilution, and reproducibly inhibit the [3H]TdR incorporation in the MLR at responder-to-suppressor cell ratios of 50:1. There is no antigen specificity or H-2 haplo-type restriction of the MLR suppression. The suppressor cells do not inhibit [3H]TdR per se, because no inhibition was observed in co-culture experiments with the EL4 tumor line or the IL 2-dependent HT-2 cell line. By using immunofluorescent staining techniques, the surface phenotype of the suppressor cells was found to be similar to that reported previously for cloned NK cells (Thy-1+, Lyt-1-, Lyt-2-, Ig-, Ia-, MAC-1-, asialo-GM1+). However, the suppressor lines showed no natural killer activity when YAC-1 target cells were used. Thus, the suppressor lines have been termed "natural suppressor" cells to indicate surface marker similarities to NK cells, both in vivo and in vitro, but different effector functions.
Inhibition of recombinant interferon-gamma-induced Ia antigen expression by shed B16 F10 melanoma cell membrane vesicles.
Authors: Poutsiaka D D , Taylor D D , Levy E M , Black P H
Published: December 2022

The expression of immune region-associated (Ia) antigens by macrophages is a prerequisite for antigen presentation, which is necessary for the activation of T helper cell function. A decrease in macrophage Ia expression is associated with a decrease in immune function in vitro. However, the effect of diseases accompanied by immunosuppression, such as cancer, on macrophage Ia expression has not been studied. The expression of Ia antigen was induced by the culture of murine peritoneal macrophages with recombinant interferon-gamma (IFN). Maximal expression was achieved after 4 days of culture. Membrane vesicles shed from the murine B16 F10 melanoma cell line inhibited the in vitro induction of Ia expression by 40 to 90% in allogeneic and syngeneic systems. Inhibition was not due to toxicity, a reduction in IFN activity, phagocytosis or contamination of the vesicle preparation with endotoxin, which is an inhibitor of Ia expression. Inhibition exerted by vesicles was prostaglandin-dependent and was over-come by increasing concentrations of IFN. It is possible that the reduction of macrophage Ia antigen expression by tumor cell products, such as shed membrane vesicles, contributes to the immunosuppression of tumor-bearing hosts. Employing IFN to reverse the inhibition provides a strategy for improving the therapy of patients with cancer.
Defective in vitro T cell colony formation in the acquired immunodeficiency syndrome.
Authors: Winkelstein A , Klein R S , Evans T L , Dixon B W , Holder W L , Weaver L D
Published: December 2022

Depressed T cell immunity is a universal characteristic of the acquired immunodeficiency syndrome (AIDS). In the present study, 25 patients with AIDS and opportunistic infections, 22 individuals with AIDS-related complex (ARC, or chronic lymphadenopathy syndrome), and 20 healthy homosexuals were evaluated by means of the T cell colony assay. Forty-seven healthy heterosexual controls showed an average of 3964 +/- 319 colonies/7.5 X 10(5) cells, with a range of 880 to 9340. The mean in the 20 healthy homosexuals (3173 +/- 483) did not differ significantly from the controls; in this group, only three patients had values less than 1000 colonies/plate. By contrast, all AIDS patients and 14 ARC patients had colony counts less than 1000. The mean value for the AIDS patients was only 24 +/- 15 (p less than 0.0005 compared with either controls or healthy homosexuals); values in the ARC group were intermediate (1180 +/- 360). The addition of interleukin 2 to the plates promoted correction of the proliferative abnormality in ARC patients. This interleukin increased colony scores in the AIDS group, but the mean value was still significantly less than controls. Comparison indicated that the colony assay is a more sensitive indicator for detecting proliferative abnormalities than responses to PHA, Con A, or pokeweed mitogen in suspension cultures.
Circadian and/or circahemidian rhythms in nine lymphocyte-related variables from peripheral blood of healthy subjects.
Authors: Levi F A , Canon C , Blum J P , Mechkouri M , Reinberg A , Mathe G
Published: December 2022

Circadian variations were investigated for nine lymphocyte-related variables in the peripheral blood of healthy subjects. Monoclonal antibodies targeted at membrane immunoglobulins (anti-Ig, anti-kappa, anti-lambda) or differentiation antigens (anti-IA and OKT3) were used to characterize respectively mature B cells (SIg+, kappa +, lambda +), cells expressing HLA-DR antigen (IA+), and T cells (OKT3+). Blood (33 ml) was drawn every 4 hr for 24 hr starting at 8.30 hr, on seven occasions in five apparently healthy male volunteers, recumbent from 23.00 hr to 07.00 hr. Leukocyte and differential counts were measured. Mononuclear cells were isolated on Ficoll-Hypaque before being incubated with monoclonal antibodies. The proportion of fluorescent cells per 100 microscopically determined cells was multiplied by the number of circulating lymphocytes per milliliter of venous blood. Temporal variations were validated by both paired t-test and cosinor. Rhythms with a period (tau) identical to 24 hr were validated with statistical significance (p less than 0.05) for total lymphocytes, OKT3+ cells and OKT3+:SIg+ ratio, and suggested (0.05 less than or equal to p less than or equal to 0.10) for lambda + and (kappa + + lambda +) cells. Rhythms with tau identical to 12 hr were also found (p less than 0.05) for OKT3+, SIg+, kappa +, and IA+ cells as well as for the OKT3+:SIg+ and the kappa +:lambda + ratios. Validated rhythms exhibited a large amplitude, e.g., peak-through differences were 40% of the 24-hr mean. This circadian and circahemidian temporal structure of immunologic variables constitutes a time-qualified reference system for investigating immune regulations and a tool for optimizing both diagnostic criteria and effectiveness of immunotherapeutic attempts.
Regulation of antibody responses by rheumatoid factor. I. Polyclonal activation of human B cells by rheumatoid factor-containing preparations from seropositive plasma.
Authors: Hobbs M V , Morgan E L , Baker N L , Weigle W O
Published: December 2022

Rheumatoid factor (RF)-containing IgM preparations isolated from the plasma of two seropositive patients were able to increase the number of Ig-secreting cells in normal human peripheral blood lymphocyte cultures. This polyclonal B cell activation was optimal in the presence of both T cells and monocytes. A relationship was established between the activator and RF in these preparations based on the ability of both to bind to insolubilized human IgG. The presence of the activator also coincided with the presence of large, RF-containing Ig complexes. These data suggest that RF contributes to the formation of B cell-stimulating immune complexes--a phenomenon with possible negative consequences in disease states characterized by these complexes.
Characterization of in vivo-activated allospecific T lymphocytes propagated from human renal allograft biopsies undergoing rejection.
Authors: Mayer T G , Fuller A A , Fuller T C , Lazarovits A I , Boyle L A , Kurnick J T
Published: December 2022

To evaluate in situ lymphocyte responses in cell-mediated immune tissue injury, we have developed an approach for propagation of human allospecific T lymphocytes directly from tissue biopsies. We have utilized renal allograft tissue obtained from eight patients undergoing cellular rejection. Needle biopsy tissue was cultured in medium containing interleukin 2 (IL 2), including recombinant-DNA-produced IL 2. In each case, lymphoblasts migrated out of the tissue and increased in numbers, especially adjacent to the tissue. In two cases in which there was no cellular infiltrate present in the biopsy, no lymphocytes proliferated in vitro. Instead, fibroblasts eventually filled the wells from these allograft biopsies. The continued presence of the allograft tissue enhanced the viability and growth of the lymphoblasts in cultures from rejecting allografts. The isolated lymphoblasts had surface markers of mature OKT3+ lymphocytes of either OKT4+ or OKT8+ subsets. OKT8+ cells predominated. There was variability (41 to 97%) in the percentage of T lymphoblasts that bore surface HLA-DR antigens. In assays of lymphoblasts obtained from eight separate renal allografts, there was donor-specific cytotoxicity, and in all but two of the cases there was donor-induced proliferation. The specificity of the cytotoxic reaction was tested by using 51Cr-labeled, PHA-stimulated target cells prepared from a panel of HLA-typed donors. Proliferation was tested after 48 hr in the presence of mitomycin C-treated peripheral blood mononuclear cells as stimulator cells by using only 10(4) responder T lymphoblasts. Of particular note was that the cytotoxicity of the isolated lymphoblasts showed specificity against both "private" HLA class I alloantigens (of the allograft donor) as well as "public" cross-reacting epitopes. This method permits the propagation and functional characterization of in vivo-activated T lymphoblasts that are obtained from the actual sites of immune-mediated injury. Preliminary studies of other tissues with diverse inflammatory processes indicate the possible widespread applicability of obtaining in vivo-activated lymphocytes.
Characterization of mononuclear phagocyte subpopulations in the human lung by using monoclonal antibodies: changes in alveolar macrophage phenotype associated with pulmonary sarcoidosis.
Authors: Hance A J , Douches S , Winchester R J , Ferrans V J , Crystal R G
Published: December 2022

Current concepts of pulmonary sarcoidosis suggest that the alveolar macrophage plays a central role in the pathogenesis of the disease. To help define the population of alveolar macrophages in sarcoidosis, we compared the surface phenotype of alveolar macrophages from patients with sarcoidosis and from normal individuals by using monoclonal antibodies (63D3, OKM1, M phi P-9, M phi S-1, 61D3, and M phi S-39) that detect surface antigens on cells of monocyte/macrophage lineage. Although almost all blood monocytes expressed surface antigens detected by each of these antibodies, only a minority of normal alveolar macrophages expressed the same surface antigens (p less than 0.05, each comparison). However, in sarcoidosis, the percentage of alveolar macrophages expressing these surface antigens was increased (p less than 0.05, each comparison with normal alveolar macrophages). Several findings supported the conclusion that the increased expression of these monocyte-lineage surface antigens on sarcoid alveolar macrophages resulted from increased recruitment of monocytes to the lung in sarcoidosis and not from abnormal "activation" of alveolar macrophages. First, alveolar macrophages expressing these antigens had an immature morphology. Second, in vitro cultivation of blood monocytes and alveolar macrophages in the presence of immune and inflammatory mediators, including mediators known to be present in the lung in sarcoidosis, did not prevent the loss of expression of monocyte-lineage surface antigens from monocytes or induce reexpression of monocyte-lineage surface antigens on alveolar macrophages. Third, the expression of monocyte-lineage surface antigens was only increased on sarcoid macrophages from patients whose lower respiratory tract contained an increased number of T lymphocytes, cells known to release monocyte chemotactic factor in sarcoidosis. Consistent with the knowledge that corticosteroids usually suppress the alveolitis of active sarcoidosis, when the expression of alveolar macrophage surface antigens was evaluated before and during therapy, the percentage of alveolar macrophages expressing monocyte-lineage surface antigens returned to normal after 1 to 3 mo of therapy.(ABSTRACT TRUNCATED AT 400 WORDS)
Activation of human thymocytes via the 50KD T11 sheep erythrocyte binding protein induces the expression of interleukin 2 receptors on both T3+ and T3- populations.
Authors: Fox D A , Hussey R E , Fitzgerald K A , Bensussan A , Daley J F , Schlossman S F , Reinherz E L
Published: December 2022

Recent studies have demonstrated that the 50KD T11 molecule is a surface component of a macrophage-independent alternative pathway of human T cell activation that is unrelated to the T3/Ti antigen-MHC receptor complex. Given the expression of T11 on all human thymocytes, it was of interest to determine whether they could be activated via this pathway. The triggering of T11 by monoclonal antibodies anti-T112 and anti-T113, directed at two unique epitopes on the molecule, induced IL 2 receptor expression on both T3+ and T3- thymocytes but did not induce IL 2 production. Consequently, in contrast to peripheral blood T cells, thymocytes did not proliferate in response to anti-T112 and anti-T113 in the absence of exogenous IL 2. These studies suggest that IL 2 receptor gene activation precedes IL 2 gene activation in T cell development. The ability of the alternative pathway of T cell activation to induce IL 2 receptor expression on T3- thymocytes implies that the T11 molecule may have an important role in early thymocyte ontogeny.
Interleukin 1 production by the human monocyte cell line U937 requires a lymphokine induction signal distinct from interleukin 2 or interferons.
Authors: Amento E P , Kurnick J T , Krane S M
Published: December 2022

A soluble product from cloned human T lymphocytes is capable of stimulating U937 cells, a line of human monocytes, to produce interleukin 1 (IL 1). We previously reported that U937 cells exposed to T lymphocyte-conditioned medium secrete mononuclear cell factor (MCF), which increases collagenase and prostaglandin E2 production by adherent rheumatoid synovial cells. Whereas structural and functional homologies between lymphocyte-activating factor (LAF, or IL 1) and MCF were described, previous attempts to measure LAF secretion by lymphokine-stimulated U937 cells were unsuccessful. Although the crude supernatants of cultured U937 cells exposed to medium from lectin-stimulated peripheral blood or cloned T lymphocytes contained MCF activity, no LAF activity was detected. After these crude supernatants were chromatographed on Ultrogel AcA54, however, and the fractions were individually assayed for IL 1, MCF and LAF activities were coeluted with apparent m.w. approximately 14,000 to 23,000. The inability to detect LAF activity in the unfractionated medium was accounted for by an inhibitor of lymphocyte proliferation present in fractions of higher m.w. The T lymphocyte product that stimulated U937 cell maturation and monokine production was secreted in response to lectin-stimulation in a dose-dependent fashion. Although we have previously demonstrated that the hormone 1,25-dihydroxyvitamin D3 caused maturational changes in U937 cells, and other investigators have reported effects of alpha and gamma interferon, these changes are dissociable from IL 1 production. Thus, a distinct lymphocyte-derived signal, necessary for the production of IL 1 by U937 cells, can be identified and dissociated from other biologic products that cause "maturational" changes. The detection of LAF activity in U937 cell supernatants requires the removal of an inhibitor of lymphocyte proliferation.