bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dextran augments delayed-type hypersensitivity by interrupting one limb of the suppressor cascade.
Authors: Battisto J R , Beckman K , Yen-Lieberman B 
Published: December 2022

Abstract
We have studied the immunomodulatory effect of dextran on the development of delayed-type contact hypersensitivity to a hapten in mice. Administration of an optimal dose of dextran 2 hours before applying picryl chloride to abdominal skin caused a twofold rise in the level of hapten-specific DTH. A study of the kinetics of development of DTH under the influence of dextran showed that comparable levels of response could be seen 2 days earlier in treated than in untreated mice, i.e., on the third day in contrast to the fifth day after sensitization. The peak of the responses, while greater in dextran-treated mice than in normal controls, remained the same at 5 days. Adoptive transfer studies revealed that comparable levels of DTH were conferred upon recipient mice by half the number of splenic cells from dextran-treated mice than that required from normal sensitized mice. Because several suppressor mechanisms are known to down-regulate DTH, we have studied dextran's effect on the neutralization of these systems as a possible explanation for its enhancing capabilities. Detailed examination was made of dextran's effect on the two suppressor T cells, Ts1 and Ts3, that act in tandem as well as its effect on the Ts1 and macrophage that work in combination. Both systems depress the efferent limb of DTH. We have found that dextran blocks the Ts1-macrophage pathway that controls DTH. Ts1 was found to arise normally in mice pretreated with dextran. Furthermore, Ts1 from dextran-treated mice produced TsF1 normally. However, we have found that dextran interferes with the production of macrophage suppressor factor (M phi-SF). Interference was partial when dextran was introduced during the interval in which macrophages were being armed with TsF1, and it was complete when dextran was put with pre-armed macrophages before they were triggered with antigen for production of M phi-SF. On the other hand, the Ts1-Ts3 limb of suppression remained unaffected by exposure to the immunomodulator. We found Ts3 arose normally in hapten-sensitized mice that had been pretreated with dextran. In addition, Ts3 became armed with TsF1 in vitro in the presence of dextran since the cells functioned properly to suppress mature DTH effector cells. Finally, TsF3 was able to act in vitro upon DTH effector cells despite the presence of dextran.(ABSTRACT TRUNCATED AT 400 WORDS)
Repopulation of the mouse thymus after sublethal fission neutron irradiation. II. Sequential changes in the thymic microenvironment.
Authors: Huiskamp R , van Vliet E , van Ewijk W 
Published: December 2022

Abstract
The stromal cells of the thymus of sham-irradiated and sublethal fission neutron-irradiated CBA/H mice were analyzed with immunohistology, using monoclonal antibodies directed to I-A and H-2K antigens as well as specific determinants for cortical and medullary stromal elements. In the control thymuses, I-A expression in the thymus shows a reticular staining pattern in the cortex and a confluent staining pattern in the medulla. In contrast, H-2K expression is mainly confluently located in the medulla. Whole body irradiation with 2.5 Gy fission neutrons reduces within 24 hr the cortex to a rim of vacuolized "nurse cell-like" epithelial cells, largely depleted of lymphoid cells. The localization of I-A antigens changes in the cortex and I-A determinants are no longer associated with or localized on epithelial reticular cells. Medullary stromal cells, however, are more or less unaffected. A high rate of phagocytosis is observed during the first 3 days after irradiation. About 5 days after irradiation, the thymus becomes highly vascularized and lymphoid cells repopulate the cortex. The repopulation of the thymic cortex coincides with the appearance of a bright H-2K expression in the cortex which is associated with both stromal cells as well as lymphoid blasts. During the regeneration of the thymus, the thymic stromal architecture is restored before the expression of cell surface-associated reticular MHC staining patterns. The observed sequential changes in the thymic microenvironment are related to the lymphoid repopulation of the thymus.
Polymorphism and tissue distribution of maternally transmitted antigen defined by cytotoxic T lymphocyte lines.
Authors: Smith R , Rich R R 
Published: December 2022

Abstract
We have developed cytotoxic T lymphocyte (CTL) lines specific for two determinants of the maternally transmitted antigen (Mta) and have used these CTL lines to study the tissue distribution of Mta. In previous reports, we characterized CTL lines specific for the Mta.1 determinant. Here, we describe CTL lines specific for the newly defined Mta.2 determinant. Mta.2-specific CTL lines lysed target cells from F1 mice of an NZB (Mtf beta) mother but did not lyse target cells from reciprocal F1 mice of any Mtf alpha mother. Backcross mice were used as the source of target cells to demonstrate that the Mta.2-specific CTL were H-2 nonrestricted in their recognition. Mta.-1- and Mta.2-specific CTL lines were used to demonstrate Mta expression on lymphoid cells taken from spleen, thymus, lymph nodes, and bone marrow. In addition, Mta was expressed on cultured cell lines of myeloid, epithelial, and mesenchymal origin. Our results suggest that Mta is not a differentiation marker restricted to lymphocyte subpopulations.
Lyt-2+ suppressor T cells are resistant to anti-Lyt-2 antibody blocking.
Authors: Hollander N 
Published: December 2022

Abstract
Lyt-2 molecules play a role in antigen recognition by cytotoxic T lymphocytes (CTL). In an attempt to determine whether Lyt-2 molecules play a similar role in suppressor T cell (Ts) functions, the effect of anti-Lyt-2 antibodies on Ts generation and effector activity was studied. Allospecific Ts were induced in allogeneic mixed lymphocyte cultures (MLC). Anti-Lyt-2 antibodies added to MLC in the absence of complement abolished CTL generation, but had no effect on concomitant induction of Ts. In a different experimental system, allospecific Ts were induced in cultures treated with pyrilamine, which blocks generation of CTL but allows differentiation of Ts. The addition of anti-Lyt-2 antibodies to pyrilamine-treated MLC resulted in unaffected induction of Ts. It was further demonstrated that the effector activity of Ts was as resistant to anti-Lyt-2 antibodies as their induction, in contrast to the cytolytic activity of CTL, which was inhibited by the same antibodies. Ts in the present experimental system were Lyt-2+ antigen-specific cells. It therefore appears that Lyt-2 molecules, although expressed on both CTL and Ts, are involved in CTL activity, but do not play an essential role in Ts function.
Effect of altered membrane fluidity on NK cell-mediated cytotoxicity. I. Selective inhibition of the recognition or post recognition events in the cytolytic pathway of NK cells.
Authors: Roozemond R C , Bonavida B 
Published: December 2022

Abstract
NK cell-mediated cytotoxicity results from membrane interactions between NK effector and target cells. The role of membrane fluidity in these events is not known. The present study was undertaken to investigate the effect of changes in membrane lipid fluidity of NK effector and NK-sensitive target cells on the lytic pathway of NK cell-mediated cytotoxicity. Fluidity was modulated by various lipids and measured by fluorescence polarization. NK effector cells treated with phosphatidylcholine complexed with polyvinylpyrrolidone (PVP) and bovine serum albumin (BSA) showed increased membrane fluidity. This fluidization of the effector cell membrane resulted in a significant inhibition of cytotoxic activity in the 51Cr-release assay. Single cell analysis revealed that the inhibition was due to a decrease in the frequency of NK target conjugates and reduced killing of conjugated targets. Rigidification of the NK effector cell membranes by treatment with cholesteryl hemisuccinate complexed with PVP and BSA also resulted in inhibition of cytotoxicity. This inhibition was post binding, because binding was increased and lysis was abrogated. Fluidization of K562 target cell membranes caused a slight but insignificant increase in their lysis by NK cells without affecting the binding step. On the other hand, rigidification of K562 membranes decreased the sensitivity of these target cells to lysis. Single cell analysis revealed that this inhibition of NK lysis is post binding, because the frequency of killers was significantly decreased. It was also shown that membrane rigidification of target cells that were programmed for lysis during the lethal hit stage and subsequently separated from effector cells, rendered the programmed cells resistant to killing during the killer cell-independent lysis step. These results demonstrate that fluidization or rigidification of the plasma membrane of either effector or target cells affect different stages of the NK cell-mediated cytolytic events.
B5, a new B cell-restricted activation antigen.
Authors: Freedman A S , Boyd A W , Anderson K C , Fisher D C , Schlossman S F , Nadler L M 
Published: December 2022

Abstract
The characterization of a new human B cell-restricted activation antigen (B5) is described in this report. With the use of a monoclonal antibody to B5, we show that B5 can be detected on peripheral blood or splenic B cells after 1 day of stimulation with either anti-immunoglobulin, protein A, Epstein Barr virus, or pokeweed mitogen. In contrast, B5 was not expressed on resting B, T, or myeloid cells. More important, B5 could not be detected on activated T cells or monocytes. The B5 antigen was expressed on some lymphoblastoid B cell lines and B cell neoplasms but was not expressed on leukemias or lymphomas of T or myeloid origin. The B5 antigen is distinct from previously reported B cell activation antigens by its m.w. and pattern of cellular expression. These studies suggest that B5 is a novel B cell-restricted activation antigen, which may be useful to study the events of early human B cell activation.
The function of antigen-presenting cells in mice with severe combined immunodeficiency.
Authors: Czitrom A A , Edwards S , Phillips R A , Bosma M J , Marrack P , Kappler J W 
Published: December 2022

Abstract
We have examined the antigen-presenting function of spleen cells in the C.B-17 scid mouse, a mutation that severely impairs the development of T and B lymphocytes. We show that antigen-presenting cells (APC) of SCID mice function normally in antigen-specific proliferative responses of primed T cells and in the antigen-specific activation of IL 2-producing T cell hybridomas. In both quantitative and qualitative terms, APC of SCID mice are equivalent to those of normal mice. These results indicate that the development and differentiation of APC function in vivo is independent of signals from mature, functional T or B lymphocytes.
Regulation of human B lymphopoiesis: effect of a urinary activity associated with cyclic neutropenia.
Authors: Landreth K S , Engelhard D , Beare M H , Kincade P W , Kapoor N , Good R A 
Published: December 2022

Abstract
Urine from a patient with cyclic neutropenia was found to contain a lymphopoietic activity that acts as a growth factor for human pre-B cells. This biologic activity was detectable during the week preceding, but not during, the period of neutropenia. This corresponded with a periodic excessive accumulation of pre-B cells in the marrow of this patient. Urine preparations were added to cultures of normal human bone marrow that had been depleted of B cells. Pre-B cells were generated in these cultures but not in cultures containing urine preparations from normal donors. Pre-B cells were also generated from bone marrow that had been depleted of 177.17+ cells and the majority of pre-B cells. This is the first report of a hemopoietic activity which affects human pre-B cells. This activity may represent a normal regulatory molecule that is periodically produced in excess in this patient.
Human splenic sinusoidal lining cells express antigens associated with monocytes, macrophages, endothelial cells, and T lymphocytes.
Authors: Buckley P J , Dickson S A , Walker W S 
Published: December 2022

Abstract
The antigenic and functional properties of splenic sinusoidal lining cells (SLC) have not been studied extensively. Some investigators have suggested that SLC are actively phagocytic, and thus part of the mononuclear phagocyte system. Others dispute this and assign the functions of endothelial cells to the SLC. During studies in situ of phenotypic subpopulations of human splenic macrophages (M phi), we found that SLC share membrane antigens (HLA-DR and OKM5), an enzyme (lysozyme), and histochemical properties (nonspecific esterases) with monocytes and M phi. In addition, we showed that LSC, like endothelial cells, synthesize factor VIII of the clotting system and also bear the receptor for transferrin. Our previous studies found that SLC express the antigens found on helper/inducer (OKT4, Leu-3a,b) and suppressor/cytotoxic (OKT8, Leu-2a) T lymphocyte subsets. We have confirmed these observations, and have shown by means of preincubation with soluble complexes of anti-human IgG-human IgG that the detection of T cell and other antigens on SLC is not due to nonspecific binding of antibodies by Fc receptors. By using techniques designed to isolate and purify splenic M phi, we were able to obtain SLC in suspension and to demonstrate that they retain the antigens detected in situ. Thus, the human splenic SLC expresses a unique combination of antigens, histochemical properties, and cell products in common with monocytes, M phi, and T lymphocytes.
In vitro migration of human large granular lymphocytes.
Authors: Bottazzi B , Introna M , Allavena P , Villa A , Mantovani A 
Published: December 2022

Abstract
Large granular lymphocyte (LGL)-enriched peripheral blood mononuclear cells were prepared on discontinuous gradients of Percoll. Migration into nitrocellulose filters was studied in a 2-hr assay with the use of modified Boyden chambers. LGL migrated into filters in response to casein or C5a. Migration depended on the presence of a concentration gradient of chemoattractant between the lower and upper compartment of the chambers. Percoll-purified high density small lymphocytes had little or no migratory capacity under these conditions, requiring a longer incubation time (4 hr) for consistent migration. Migratory capacity in response to stimuli correlated with the frequency of LGL in the various fractions of Percoll gradients. Fractionation of LGL-enriched Percoll preparations with monoclonal antibodies and immunoadsorbent columns or a cell sorter revealed that cells with migratory capacity in response to stimuli were B73.1+ and OKT3-, thus confirming that migrating cells were LGL. LGL preincubated with interferon (IFN) showed enhanced spontaneous motility but no increased responsiveness to chemoattractants. IFN did not modify the migratory capacity of small lymphocytes. The prompt migration of LGL in response to stimuli is consistent with the hypothesis that these cells may serve as one of the first easily mobilizable lines of resistance against infectious agents and tumors. The migration assay described here may offer a better insight into the functions and regulation of LGL.
Type II collagen-induced arthritis in mice. III. Suppression of arthritis by using monoclonal and polyclonal anti-Ia antisera.
Authors: Wooley P H , Luthra H S , Lafuse W P , Huse A , Stuart J M , David C S 
Published: December 2022

Abstract
Pretreatment of mice genetically susceptible to type II collagen-induced arthritis (CIA) with monoclonal or polyclonal antisera specific for I region gene products (Ia antigens) suppressed or delayed the onset of CIA, whereas pretreatment with anti-Ia to an irrelevant haplotype was without effect. The humoral response to type II collagen was transiently depressed 14 days after immunization but antibody levels did not differ significantly after 28 days. The peak delayed-type hypersensitivity to type II collagen was unaffected by anti-Ia treatment. Monoclonal antibody of one anti-Ia specificity enhanced both the antibody response and the arthritis incidence in one mouse strain.
Induction of interferon-gamma production by human natural killer cells stimulated by hydrogen peroxide.
Authors: Munakata T , Semba U , Shibuya Y , Kuwano K , Akagi M , Arai S 
Published: December 2022

Abstract
Interferon (IFN)-inducing activity of hydrogen peroxide in human peripheral mononuclear cells was investigated. Among the mononuclear cells, purified nonadherent cells produced IFN, but not B cells and monocytes. The maximal titer of IFN by purified nonadherent cells was observed after a 72-hr cultivation in the presence of 10(-2) mM H2O2 without affecting their viability. Furthermore, the purified nonadherent cells, but not the unpurified mononuclear cells, showed an augmented cytotoxicity to K562 when stimulated with hydrogen peroxide. By using Percoll discontinuous density gradient centrifugation, peripheral blood nonphagocytic and nonadherent mononuclear cells were divided into the low and high density fractions for which natural killer (NK) cells and T cells were enriched, respectively. The NK-enriched low density fractions, but not the T cell-enriched high density fractions, showed IFN production by the stimulation of hydrogen peroxide. IFN production as well as large granular lymphocytes and HNK-1+, Leu-11+ cells of the NK-enriched fractions were abrogated by treatment of the cells with monoclonal antibody against human NK cells (HNK-1+) but not against T cells (OKT3) in the presence of complement. Moreover, hydrogen peroxide-inducing IFN production seems to be regulated by monocytes. The antiserum neutralizing IFN-alpha and IFN-beta failed to neutralize substantially IFN-produced NK cells. The treatment with either pH 2 or antiserum-neutralizing human IFN-gamma resulted in marked reduction, indicating that a major part of IFN was IFN-gamma. The purified nonadherent cells showed IFN production and augmented cytotoxicity when cultured separately from activated macrophages by opsonized zymosan; furthermore, both IFN production and enhancement of cytotoxicity were abrogated by catalase. These results suggest that both exogenous and endogenous hydrogen peroxide might be responsible for a part of immunoregulation.
Activation requirements for antigen- and mitogen-induced interferon-gamma release from cytotoxic T lymphocytes.
Authors: Klein J R , Pasternack M S , Bevan M J 
Published: December 2022

Abstract
We have studied the activation signals that regulate interferon-gamma (IFN-gamma) secretion from murine cytotoxic T lymphocytes (CTL) upon binding mitogen or antigen. CTL clones were found to require at least 1 hr of stimulation with concanavalin A (Con A) in order to produce detectable levels of IFN-gamma. Full activation of IFN-gamma synthesis in CTL clones occurred after stimulation for 2 hr or more, and in those cultures CTL continued to produce high levels of IFN-gamma even after the effects of Con A had been neutralized. Splenic T cells and uncloned long-term CTL lines required a longer period of stimulation than cloned CTL for Con A-induced IFN-gamma secretion. The relationship between IFN-gamma secretion and cytotoxic activity was studied in an antigen-specific system. These studies reveal marked differences in the types of effector responses generated by CTL upon contact with antigen, demonstrating that some antigen-bearing cells promote high levels of IFN-gamma secretion and are poorly lysed by CTL, whereas other cell lines are lysed with high efficiency by CTL but induce low levels of IFN-gamma secretion.
Human B cell responsiveness to B cell growth factor after activation by phorbol ester and monoclonal anti-mu antibody.
Authors: Suzuki T , Butler J L , Cooper M D 
Published: December 2022

Abstract
The effect of phorbol ester on human B cell activation was examined. Picomolar to nanomolar concentrations of phorbol ester induced a high level of proliferation in small IgM-positive B cells isolated from peripheral blood by fluorescence-activated cell sorting. The addition of optimal doses of anti-mu antibody resulted in enhanced proliferation of phorbol ester-activated B cells. The addition of B cell growth factor (BCGF) to phorbol ester-activated B cells also resulted in a dose-dependent synergistic effect and maximal enhancement on day 3. BCGF activity could be absorbed with either phorbol ester- or anti-mu-activated B cells, but not with resting B cells, thus confirming the induction of functional BCGF receptor expression. Cell proliferation was not necessary for the induction of functional BCGF receptors. Phorbol ester was a more efficient inducer of BCGF receptor expression than was anti-mu antibody; gamma-interferon treatment had no effect. BCGF enhanced transferrin receptor expression by phorbol ester-activated B cells. The results suggest that phorbol ester-activated small B cells can be used to monitor BCGF activity, and this synergistic combination may be useful in establishing BCGF-dependent B cell clones in culture.
Co-immunoprecipitation of the Ly-5 molecule and an endogenous protease: a proteolytic system requiring a reducing agent and Ca2+1.
Authors: Ewald S J , Refling P H 
Published: December 2022

Abstract
Sodium [3H]borohydride- and [35S]methionine-labeled Ly-5 molecules from mouse thymocytes and T lymphoma cells were isolated with specific antibody and Staphylococcus aureus Cowan I (SaCI) strain; after extensive washing of the complexes, elution with Laemmli's reducing buffer (0.05 M Tris [pH 6.8 or 6.0], 4% sodium dodecyl sulfate [SDS], and 2% 2-mercaptoethanol [2-ME]) resulted in partial breakdown of the isolated Ly-5 molecules from a Mr = 175,000 to 150,000. Other proteins present during the elution step showed no evidence of proteolysis. 2-ME and SDS were required for proteolysis; although addition of exogenous Ca2+ during elution was not necessary, both EDTA and EGTA inhibited breakdown of the molecule that could be overcome by excess Ca2+. Of a variety of protease inhibitors and thiol-reactive agents tested, only TAME and oxidized glutathione blocked proteolysis almost completely. SaCI, serum, and contaminating antibodies were ruled out as the source of the proteolytic activity. More stringent preclearing and washing conditions did not eliminate endogenous proteolysis of the Ly-5 molecule. The endogenous proteolytic fragment had a Mr distinct from the tryptic fragment of the Ly-5 molecule. We conclude that the Ly-5 molecule may be autolytic or tightly associated with a distinct cellular protease.
Antigen-specific anti-phosphocholine antibodies: binding site studies.
Authors: Claflin J L , Hudak S , Maddalena A , Bender T 
Published: December 2022

Abstract
The present investigation extends our initial evaluation of the evolution of antigen selection mechanisms for antibodies of a "single" specificity. The binding sites of 11 mouse anti-PC antibodies produced in response to the bacterium P. morganii or the nematode A. suum were characterized for both hapten and hapten plus carrier specificity. All of the anti-P. morganii HP belonged to the M603 anti-PC antibody family, whereas all the A. suum HP belonged to the M511 family. Of the eight anti-P. morganii HP, six exhibited a fine specificity profile for PC and choline analogues only slightly different from M603 Id+ HP induced by S. pneumoniae and PC-protein. These six and a seventh HP, whose hapten binding profile was unique, were also unusual in showing strong reactivity for a soluble PC containing extract from P. morganii. All three anti-A. suum-specific HP studied in detail had hapten-binding profiles remarkably similar to each other, a finding that is in contrast to M511 Id+ HP to S. pneumoniae and PC-protein. All three HP also showed evidence for preferential binding activity for A. suum, although this was not as dramatic as that seen with the anti-P. morganii HP. These data support our hypothesis that antigen selection of anti-PC antibodies occurs not so much for PC itself as it does for the carrier (microbial) determinants to which PC is attached.