bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous production of IL-2, IL-4, and IFN-gamma by activated human CD4+ and CD8+ T cell clones.
Authors: Paliard X , de Waal Malefijt R , Yssel H , Blanchard D , Chrétien I , Abrams J , de Vries J , Spits H
Published: December 2022

In the present study, we have investigated the ability of human T cells to secrete IL-2, IL-4, and IFN-gamma. IL-4 and IFN-gamma were quantified with enzymatic immunoassays and IL-2 with a biologic assay by using the murine IL-2-dependent cell line CTLL-2. PBL, stimulated with Con A or with a combination of the phorbol ester 13-O-tetradecanoylphorbol-12-acetate and the Ca2+ ionophore A23187 secreted IL-2, IL-4, and IFN-gamma. The kinetics of the secretion of the three lymphokines was investigated with two CD4+ clones; one (GEO-2) that produced IL-2, IL-4, and IFN-gamma and another (HY640), that produced only IL-2 and IFN-gamma. Significant IL-2, IL-4, and IFN-gamma production was observed after only 8 h of activation. Maximal levels of IL-2 and IL-4 were found 20 h after the onset of the stimulation which subsequently decreased. In contrast, IFN-gamma levels continued to increase in a period up to 40 h and then leveled off. In spite of these differences in secretion, the kinetics of accumulation of mRNA did not differ. The IL-2, IL-4, and IFN-gamma mRNA were detectable 2 h after stimulation and continued to accumulate for a period up to 20 h. In a series of 22 CD4+ clones, 21 were able to secrete all three lymphokines upon stimulation. Almost all CD8+ clones were able to produce IL-2 and IFN-gamma, but only six of the 23 CD8+ T cell clones secreted IL-4. In addition, five CD4+ (allo)antigen-specific T cell clones were tested for IL-2, IL-4, and IFN-gamma secretion upon specific stimulation. Two alloantigen-specific and two tetanus toxoid-specific T cell clones secreted IL-2, IL-4, and IFN-gamma simultaneously, whereas one alloantigen-specific T cell clone secreted IL-2 and IFN-gamma, but not IL-4. A supernatant of the CD4+ T cell clone GEO-2, that contained high levels of IFN-gamma and IL-4, was unable to induce the low affinity receptor for IgE, CD23, on a Burkitt lymphoma cell line. However, after separation of IL-4 from IFN-gamma by using HPLC, the IL-4-containing fraction-induced CD23, which could be blocked by the fraction that contained IFN-gamma and by a polyclonal rabbit anti-IL-4 antiserum. Finally, the partly purified IL-4, that was devoid of IL-2, promoted the growth of the clone GEO-2.
Differential induction by immune interferon of the gene products of the HLA-D region on the melanoma cell line MeWo and its metastatic variant MeM 50-10.
Authors: Maio M , Gulwani B , Tombesi S , Langer J A , Duigou G J , Kerbel R S , Fisher P B , Ferrone S
Published: December 2022

This study has shown for the first time an association between the metastatic properties of two autologous melanoma cell lines and their susceptibility to induction of HLA class II Ag by IFN-gamma. After in vitro incubation with IFN-gamma the melanoma cell line MeWo did not acquire reactivity with anti-HLA class II antibodies, whereas its metastatic variant MeM 50-10 did. The differential susceptibility to induction of HLA class II Ag on the two cell lines cannot be accounted for by either differences in the number and affinity of IFN-gamma receptors or in the sensitivity to IFN-gamma, but most likely reflects an intrinsic property of each cell line. Serologic and immunochemical investigations with anti HLA-DR, DQ, and DP mAb have indicated that only HLA-DR Ag are induced by IFN-gamma on MeM 50-10 cells. Northern blot analysis with HLA-DR beta, DQ beta, and DP beta probes suggest that different mechanisms underlie the differential susceptibility to induction by IFN-gamma of the gene products of the HLA-D region. The regulatory mechanism(s) that control the expression of HLA class II Ag appear to be different from those controlling the expression of the melanoma-associated Ag tested, inasmuch as the modulation of the latter by IFN-gamma did not differ on the two melanoma cell lines.
Immunosuppression of collagen-induced arthritis in mice with an anti-IL-2 receptor antibody.
Authors: Banerjee S , Wei B Y , Hillman K , Luthra H S , David C S
Published: December 2022

The use of an anti-IL-2R antibody, 7D4, was investigated in vivo in the suppression of collagen-induced arthritis in mice. 7D4 was shown to reduce the incidence of arthritis in a group of mice immunized with type II collagen as compared with a group similarly immunized with collagen and treated with a control isotype matched anti-Forsmann antibody. 7D4 was also shown to reduce the severity of arthritis in the treated mice as compared to the mice in the group treated with the control antibody. Anti-IL-2R antibodies may be useful in the treatment of autoimmune diseases by selectively suppressing activated T cells.
Stimulation of the beta-subunit of the IL-2 receptor induces MHC-unrestricted cytotoxicity in T acute lymphoblastic leukemia cells and normal thymocytes.
Authors: Colamonici O R , Rosolen A , Cole D , Kirsch I , Felix C , Poplack D G , Neckers L M
Published: December 2022

Recently, several laboratories have identified a novel protein(s) of 70,000 to 75,000 Da (IL-2R beta-subunit) that, when expressed with the p55 Tac protein (alpha-subunit), imparts high affinity IL-2 binding. Expression of the beta-subunit mediates acquisition of MHC-unrestricted cytotoxicity in large granular lymphocytes. We report that thymocytes and T acute lymphoblastic leukemia cells express the beta-subunit of the IL-2R in the absence of detectable alpha-subunit expression and that IL-2 induces acquisition of MHC-unrestricted cytotoxic activity in these cells through stimulation of the beta-subunit.
Molecular associations of IA antigens after T-B cell interactions. I. Identification of new molecular associations.
Authors: Shivdasani R A , Thomas D W
Published: December 2022

In this report we report the identification of novel molecular associations involving the MHC class II (Ia) Ag expressed on the surface of Ag-presenting B lymphocytes. Biosynthetically radiolabeled murine B cells were incubated for 2 h in the presence or absence of T lymphocytes before treatment with the cleavable cross-linking reagent dimethyl-3,3'-dithiobispropionimidate. Anti-Ia immunoprecipitates of solubilized cell extracts revealed novel cross-linked products of Mr 90,000 to 95,000 which, upon cleavage of the cross-linker, could in part be resolved into native Ia and other structures of approximately Mr 67,000. The detection of the cross-linked products was significantly enhanced in B cells that had been co-cultured with T lymphocytes, but not with other cell types, and co-culture with various monoclonal T cell lines resulted in different levels of enhancement. Detection of the 90- to 95-kDa cross-linked products appeared to be independent of the foreign Ag for which the T cells were specific and could be enhanced when either cell type was replaced by a plasma membrane fraction, indicating that it resulted from direct cell-cell contact. These results suggest that some proportion of the Ia glycoproteins expressed on the surface of B cells become associated with other structures of Mr 67,000 upon Ag-non-specific interactions between T and B lymphocytes.
Effects of influenza A virus on human neutrophil calcium metabolism.
Authors: Hartshorn K L , Collamer M , Auerbach M , Myers J B , Pavlotsky N , Tauber A I
Published: December 2022

Bacterial superinfection in influenza A virus-related illness may in part be explained by virus-induced neutrophil dysfunction. We here provide evidence that this effect is related to abnormal calcium metabolism of virus-infected cells. Neutrophils exposed to influenza virus for 0.5 h at 37 degrees C showed depressed O2- generation and release of radiolabeled arachidonic acid upon stimulation with FMLP. The peak cytosolic Ca2+ level achieved by virus-infected neutrophils after FMLP stimulation was significantly depressed as is efflux of 45Ca2+. This deficient Ca2+ mobilization could not be attributed to alterations of inositol phosphate production or Ca2+ influx in response to FMLP, both of which were unaffected by prior virus infection. Given these findings, the immediate effects of influenza virus on neutrophil Ca2+ metabolism were examined. The virus itself caused a rise in cytosolic Ca2+ and an efflux of 45Ca2+ without any corresponding 45Ca2+ influx. Total cell Ca2+ however was not depleted as measured by atomic absorption. Influenza virus, therefore, causes neutrophil activation leading to significant perturbations in Ca2+ metabolism and later to impaired mobilization of Ca2+ stores. This system offers a model for phagocyte deactivation and an opportunity to define control mechanisms of signal transduction.
Degradation of plasmodial antigens by human neutrophil elastase.
Authors: Janoff A , Roth W J , Sinha S , Barnwell J W
Published: December 2022

Human neutrophil elastase (HNE) has been well-studied with respect to its role in pathologic states, but less is known about the physiologic functions of this important granulocyte enzyme. In the present study, we show that HNE can degrade the major circumsporozoite protein of the infective (sporozoite) stage of Plasmodium vivax malaria, and that this enzyme can also interfere with the cytoadherence of human E infected with Plasmodium falciparum (strain K+ FMG-FCR3) (IE). Cytoadherence reactions are not only blocked by treatment of IE with as little as 10 fg HNE/IE, but already adherent IE are also removed by the enzyme. Normal E surface Ag are not extensively destroyed by these doses of HNE. This suggests that the effect of HNE on cytoadherence is selective and probably due to degradation of the malarial Ag exported to the IE surface and responsible for the formation of "recognition knobs" upon which the cytoadherence reaction depends. This conclusion, in turn, was supported by the results of Western blot analysis showing that HNE degrades a high m.w. Ag found exclusively in membrane extracts of IE. Our results suggest that one physiologic role of HNE may be degradation of parasitic antigens during host defense against malaria.
Heterogeneity of long-term cultured activated killer cells induced by anti-T3 antibody.
Authors: Yun Y S , Hargrove M E , Ting C C
Published: December 2022

The present study has characterized the short term and long term cultured murine-activated killer (AK) cells that are induced by antibody directed against the epsilon-chain of T3 complex. The conventional lymphokine AK (LAK) cells were generated by culturing normal B6 spleen cells with purified human rIL-2. The alpha T3-induced AK cells (T3AK) were induced by culturing normal B6 spleen cells with alpha T3 and were then maintained in culture medium supplemented with human rIL-2 and/or alpha T3. After initial activation with alpha T3, lymphocyte proliferation and generation of cytotoxic effectors (T3AK) were noted, and these events were related to the endogenous production of IL-2 and IL-4. Addition of alpha IL-2 and/or alpha IL-4 suppressed both the proliferative response and the cytotoxic response induced by alpha T3. In comparing the T3AK cells with the conventional LAK cells, there were many similarities as well as some distinct differences. Both cells displayed a similar cytotoxic spectrum against a variety of tumor targets. The T3AK cells usually gave much higher levels of cytotoxic activity against susceptible targets. However, the susceptibility of different tumor targets to conventional LAK cells and T3AK cells varied. The time course for the generation of lytic activity also differed between the conventional LAK and T3AK cells. One distinct difference was their ability to survive in vitro. The conventional LAK cells survived in culture for only 1 wk. The T3AK cells could survive for at least 4 to 5 wk with active growth. The serologic phenotype of the LAK precursors was asialo GM1 (AsGM1+) cells, but the T3AK precursors could be either AsGM1+ or AsGM1-, depending on the target cell. The LAK effectors were both Lyt-2+ and Lyt-2-, but the short-term T3AK effectors were exclusively Lyt-2+. The long term T3AK cells (cultured for more than 2 wk) were found to consist of Lyt-2+ and Lyt-2- cells, and these subsets of T3AK cells showed different target specificities. These findings demonstrate the heterogeneity of LAK and T3AK cells, and this heterogeneous property may contribute to their diversity in specificity against different tumor targets and thus may affect their effectiveness in the immunotherapy of cancer.
Intracellular interference with antigen presentation.
Authors: Leyva-Cobian F , Unanue E R
Published: December 2022

Murine peritoneal macrophages were cultured with heat-killed Listeria monocytogenes organisms and then with the protein hen egg white lysozyme. Hen egg lysozyme is well known to need intracellular processing for presentation to T cells. The presentation to T cells of lysozyme was affected despite no reduction in the amount taken up or catabolized by the macrophage. This interference with Ag presentation was not found if the macrophages were cultured with lysozyme before the Listeria pulse. The interference with Ag presentation induced by Listeria was found for a second Ag (conalbumin). Uptake of Listeria did not affect the presentation of the lysozyme peptide 46-61, indicating that MHC class II molecules were available at the macrophage surface. Other materials that are retained in the macrophages affected presentation of lysozyme but not of the processed peptide. These included SRBC, dextran, sucrose, cellobiose, polyvinyl pyrrolidone, sodium dextran sulfate, Ficoll, and polyethylene glycol. Except for SRBC, which were not tested, the remaining molecules did not interfere with presentation of 46-61 by formaldehyde-fixed macrophages, an indication that they did not affect the peptide interaction with class II molecules. Finally, uptake of latex beads did not affect presentation of lysozyme. We conclude that retention in the macrophage of a variety of soluble or particulate molecules can interfere with the intracellular events that result in the creation of an immunogenic determinant. This interference is independent of the catabolism of the Ag or of the availability of class II molecules to bind peptides.
Biochemical properties of glycoproteins involved in lymphocyte recognition of high endothelial venules in man.
Authors: Jalkanen S , Jalkanen M , Bargatze R , Tammi M , Butcher E C
Published: December 2022

Lymphocyte interactions with high endothelial venules (HEV) are important to the in vivo migration of normal and neoplastic lymphocyte populations. We have previously described an 85- to 95-kDa lymphocyte surface glycoprotein(s) defined by mAb Hermes-1, that is involved in the recognition of HEV by human lymphocytes: antibodies against distinct epitopes of the Hermes-1 Ag differentially inhibit lymphocyte binding to lymph node, mucosal, or synovial HEV. Here we characterize further the Hermes-1-defined glycoproteins. No well defined differences were observed between the Hermes-1 Ag immunoprecipitated from PBL and from mucosa- vs lymph HEV-specific cell lines. The Ag is an acidic (isoelectric point = 4.2) sulfated molecule bearing both O-linked and (3,4) N-linked oligosaccharide side chains. A subset of the Hermes-1-immunoprecipitated species is modified by covalent linkage to chondroitin sulfate, yielding a Mr of approximately 180 to 200 kDa. Pulse-chase labeling reveals a major precursor of 76 kDa that appears to be processed either to the 85- to 95-kDa form or, by addition of chondroitin sulfate, to a 180- to 200-kDa form. The potential role of these structural modifications, and particularly of chondroitin sulfate, in the function of the putative adhesion molecules is discussed.
Thy-1+ epidermal cells in nude mice are distinct from their counterparts in thymus-bearing mice. A study of morphology, function, and T cell receptor expression.
Authors: Nixon-Fulton J L , Kuziel W A , Santerse B , Bergstresser P R , Tucker P W , Tigelaar R E
Published: December 2022

We have evaluated the morphology, function, and TCR mRNA and DNA profiles of Thy-1+ epidermal cells (EC) derived from athymic (nude) mice. Based on these criteria we demonstrate that Thy-1+ EC in nude mice are predominantly round and angular and located in follicular epithelium, as compared to predominantly dendritic, interfollicular Thy-1+ EC found in normal CBA or BALB/c mice. Functionally, Thy-1+ EC from normal mice proliferate and elaborate IL-2 in response to stimulation by Con A; by contrast, nude Thy-1+ EC fail to proliferate or secrete IL-2 in response to Con A. Nude Thy-1+ EC proliferate markedly in response to low-dose IL-2 alone; Thy-1+ EC from normal mice give only modest proliferative responses to IL-2. Both populations of cells proliferate and elaborate IL-2 in response to PMA and calcium ionophore. Short-term cultured Thy-1+ EC from nude mice resemble Thy-1+ EC from normal animals in that they express no detectable functional TCR-alpha and beta-RNA. Normal Thy-1+ EC express abundant levels of functional RNA for TCR-gamma and delta-chains and for the CD3 delta-chain, whereas nude Thy-1+ EC produce no detectable TCR-delta and no CD3 delta-RNA and only truncated, presumably germ-line TCR-gamma transcripts, as suggested by lack of hybridization with gamma-V region probes and by lack of detectable rearrangements in the gamma-genes. These phenotypic, functional, and genotypic characteristics of Thy-1+ EC from nude mice suggest that these cells are at a very early stage of T cell differentiation.
The CD2 ligand LFA-3 activates T cells but depends on the expression and function of the antigen receptor.
Authors: Bockenstedt L K , Goldsmith M A , Dustin M , Olive D , Springer T A , Weiss A
Published: December 2022

The T cell Ag receptor (CD3/Ti) and the sheep E receptor (CD2) expressed on the surface of human T cells are both capable of initiating intracellular signals necessary for T cell activation. CD3/Ti interacts with Ag to initiate cellular immune responses. Although the exact function of CD2 is unknown, lymphocyte function-associated Ag 3 (LFA-3), a 55- to 70-kDa receptor expressed on a broad spectrum of hemopoietic and nonhemopoietic cells, has recently been shown to be its natural ligand. We show here that although purified multimeric LFA-3 is not capable of initiating transmembrane signaling events on its own, the combination of LFA-3 and the anti-CD2 mAb CD2.1 induces intracellular calcium increases, phosphatidylinositol second messenger generation and lymphokine secretion in the T cell leukemic line Jurkat. In order to study the signaling requirements of CD2, we compared the ability of CD2 mAb and LFA-3 to initiate activation signals in Jurkat and in three Jurkat-derived mutants. A CD3-CD2+ mutant failed to increase calcium or exhibit phosphatidylinositol hydrolysis to either the combination of agonist CD2 mAb 9-1 and 9.6 or LFA-3 and CD2.1. Reconstitution of the Ag receptor by transfection of the Ti-beta-chain restored the expression of the CD3/Ti complex and the ability to respond to either combination of CD2 ligands. However, no response to CD2 ligands was detected in a CD3+CD2+ mutant selected for signaling defects to CD3/Ti ligands. Complementation of the CD3/Ti signaling defect by cell fusion also restored competency to respond to CD2 agonists. These results demonstrate that LFA-3 under appropriate conditions can activate T cells via the CD2 complex and that this activation requires not only the cell surface expression of the CD3/Ti complex but also a functional Ag receptor pathway.
Triggering of co-mitogenic signals in T cell proliferation by anti-LFA-1 (CD18, CD11a), LFA-3, and CD7 monoclonal antibodies.
Authors: Carrera A C , Rincón M , Sánchez-Madrid F , López-Botet M , de Landaźuri M O
Published: December 2022

Proliferative T cell responses were elicited in a comitogenic assay when purified mAb against CD 18, CD11a, LFA-3, and CD7 were immobilized onto solid plastic surfaces together with submitogenic doses of mAb against the CD3 complex. The proliferative response was associated to the production of IL-2 and to the expression of IL-2R. We explored the possibility that a second signal provided by either PMA or a Ca2+ ionofore could replace the anti-CD3 mAb in the comitogenic assay. Interestingly, our data clearly indicate that PMA but not the ionofore was capable of mediating the co-mitogenic effect in conjunction with solid-bound mAb (CDw18, CD11a, LFA-3, and CD7). We also demonstrate that the mAb (anti-CD4 and anti-CD2) which have been previously described as co-mitogenic in combination with anti-CD3 are capable of eliciting this activating signal in the presence of PMA. These data indicate that mAb to certain cell surface differentiation Ag that in soluble form inhibit T cell function such as LFA-1, LFA-3, and CD2 can under appropriate conditions induce co-mitogenic signals on T cells. Our results support the hypothesis that several cell surface differentiation Ag may participate in conjunction with the T3-Ti complex in the transmembrane signal transduction leading to T cell activation.
Structure-activity studies of human IL-1 beta with mature and truncated proteins expressed in Escherichia coli.
Authors: Lillquist J S , Simon P L , Summers M , Jonak Z , Young P R
Published: December 2022

IL-1 beta is synthesized as an inactive 31-kDa intracellular protein, which is then processed upon secretion to an active 17-kDa carboxyl-terminal fragment. To identify the minimal portion of IL-1 beta required for activity, we constructed several deletion mutants of mature IL-1 beta. These included three amino-terminal deletions of 10, 16, and 81 amino acids, two carboxyl-terminal deletions of 17 and 72 amino acids, and one internal fragment between amino acids 17 and 81. Expression of the mutants was monitored by Western blots and immunoprecipitation. With one exception, all of these mutants and the full length 17-kDa IL-1 beta were expressed as soluble protein in Escherichia coli and could be assayed for activity and receptor binding in lysates without further purification. Whereas the intact 17-kDa IL-1 beta retained full biologic activity (greater than 10(7) U/ml of lysate) and competed for binding with 125I-labeled IL-1 beta, none of the lysates containing IL-1 beta deletion mutant proteins had activity or competed for binding to receptor at significantly higher concentrations. The loss of function in the smallest C-terminal deletion mutant does not appear to be due to the direct involvement of these C-terminal residues in receptor binding because both monoclonal and polyclonal antisera directed to this region bind to IL-1 beta but do not neutralize its activity. Therefore, this region is probably indirectly involved in sustaining the structure of the receptor-binding site.
Tumor necrosis factor-alpha affects LTR-controlled oncogene expression in transformed mouse fibroblasts at the post-transcriptional level.
Authors: Seliger B , Stark G , Pfizenmaier K
Published: December 2022

Potential mechanisms of TNF-alpha action on tumor cells have been investigated in a model of mouse fibroblasts transformed by distinct retroviral vectors carrying the v-mos, c-myc, and v-Ha-ras oncogene, respectively. Treatment of v-mos and c-myc transformed cells with murine rTNF-alpha in non-cytotoxic concentrations caused a strong inhibition of both proliferative capacity in monolayer culture and colony formation in soft agar. In contrast, v-Ha-ras transformed cells showed little sensitivity to TNF-alpha treatment. These changes in cell growth characteristics of v-mos and c-myc transformants was preceded by a selective reduction of oncogene-specific steady RNA levels, whereas no RNA down-regulation was observed for v-Ha-ras transformants. An unchanged transcriptional activity of the LTR-controlled v-mos and c-myc genes, but a decreased half-life of oncogene-specific mRNA suggests that TNF-alpha primarily affects stability of v-mos and c-myc RNA without influencing the activity of retroviral promoters. This is confirmed by an unchanged chloramphenicol acetyl transferase activity in TNF-treated LTR-chloramphenicol acetyl transferase transformants. Removal of TNF-alpha from cultures of reverted cells provoked a rapid retransformation, with full recovery of neoplastic growth characteristics 10 days after abrogation of TNF-alpha treatment. These data suggest that in cases of non-cytocidal action of TNF-alpha persistent suppression of tumor cell growth requires continuous TNF-alpha treatment.
Possible role of human lymphocyte receptor for IgE (CD23) or its soluble fragments in the in vitro synthesis of human IgE.
Authors: Sarfati M , Delespesse G
Published: December 2022

The present study demonstrates that human rIL-4 is capable of inducing the secretion of IgE by PBMC. At a concentration of 200 U/ml, an IgE response was observed in 11/26 cultures of PBMC from normal donors and in 12/15 cultures from allergic individuals. The same rIL-4-stimulated cells released significant amounts of IgE-binding factors (IgE-BF) in their culture supernatant. These IgE-BF were shown for the first time to bind simultaneously to some mAb against Fc epsilon R II (mAbER) and to soluble IgE. The lack of correlation between the rIL-4-induced secretion of IgE-BF and IgE indicates that the production of IgE-BF or the expression of Fc epsilon R II is not the only factor involved in the induction of IgE synthesis by rIL-4. However, the observation that mAbER suppressed the rIL-4-induced IgE synthesis strongly suggests that either Fc epsilon R II or IgE-BF are necessary for an IgE response. Finally, the spontaneous in vitro synthesis of IgE by enriched B cell preparations isolated from atopic donors was suppressed in an isotype-specific manner by the same mAbER or by their F(ab')2 fragments. These observations suggest that the ongoing IgE synthesis by in vivo pre-activated B cells is also regulated by IgE-BF or Fc epsilon R II. It is concluded that Fc epsilon R II or IgE-BF play an essential role both in the induction of IgE synthesis by normal B cells and in the ongoing IgE synthesis by in vivo activated B cells from allergic donors.
Avian T cells expressing gamma delta receptors localize in the splenic sinusoids and the intestinal epithelium.
Authors: Bucy R P , Chen C L , Cihak J , Lösch U , Cooper M D
Published: December 2022

A panel of murine mAb specific for the chicken homologues of the CD3, CD4, CD8, TCR gamma delta, and TCR alpha beta has been used to study the distribution of T cells expressing these markers in sections of chicken lymphoid tissues. These studies have revealed that the T cells possessing the two classes of TCR occupy distinct histologic microenvironments. The TCR1+ cells (gamma delta TCR homologue) are localized preferentially in the splenic sinusoids and the intestinal epithelium, where most of them express the CD8 homologue. The TCR2+ cells (alpha beta TCR homologue), a majority of which express the CD4 homologue, are found primarily in the splenic periarteriolar sheath and the lamina propria of the intestine. The frequency and distribution of the two classes of T cells in the thymus is also unique. The different tissue homing patterns of the TCR1 and TCR2 cells suggest that they represent separate lineages of T cells with distinctive physiologic roles.
IL-4 bypasses the immune suppressive effect of cyclosporin A during the in vitro induction of murine cytotoxic T lymphocytes.
Authors: Heeg K , Gillis S , Wagner H
Published: December 2022

We have analyzed at the clonal level the effect of IL-4 on the immune suppressive action of cyclosporin A (CsA) during the in vitro primary activation of anti-MHC alloantigen-reactive murine CD8+ CTL. Although neither IL-4 nor IL-2 alone were able to overcome the CsA-mediated suppression, the addition of IL-4 in the presence of IL-2 restored in a dose-dependent manner the induction of cytolytic activity. On the other hand, CsA greatly impaired proliferative responses of alloantigen-reactive CD8 T cells, thereby operationally dissecting proliferative responsiveness from acquisition of cytolytic activity during primary activation of alloantigen-reactive CD8+ T cells. The existence of a CsA-resistant induction pathway for Ag-specific CD8+ T cell-mediated cytolytic activity may be of relevance for experimental and clinical organ transplantation.
IgE receptor on human lymphocytes. IV. Further analysis of its structure and of the role of N-linked carbohydrates.
Authors: Letellier M , Nakajima T , Delespesse G
Published: December 2022

Previous studies have shown that the low affinity receptor for IgE (Fc epsilon R II) on human B lymphocytes was comprised of three components with apparent Mr of 45, 65 to 95, and 37 kDa. The present results indicate that the 37-kDa component is a soluble degradation fragment of the 45-kDa component and they also suggest that the 65- to 95-kDa component is probably made of aggregates of the above components that are formed after solubilization of the cells. The 45-kDa component appears to be a glycoprotein containing several sialic acid residues, O-linked carbohydrates and one N-linked carbohydrate chain that is of the complex type. Partial digestion of the purified 65- to 95-, 45-, and 37-kDa molecules with alpha-chymotrypsin or protease V8 generates several fragments with identical mobility on SDS-PAGE. The 37 kDa is not N-glycosylated but like the IgE-binding factors present in the culture supernatant of Fc epsilon R-bearing cells, it contains sialic acid and O-linked carbohydrates. On incubation with protease inhibitors, the Mr of IgE-binding factors (BF) is shifted from 25-27 to 37 kDa, indicating that IgE-BF are derived from the proteolytic cleavage of the 37-kDa molecule, previously identified as a membrane component of Fc epsilon R. On incubation with N-glycosylation inhibitors, the production of IgE-BF is significantly increased indicating that N-glycosylation inhibits the degradation of Fc epsilon R into IgE-BF. Inasmuch as the effect of glycosylation inhibitors is not prevented by monensin, it is concluded that all the IgE-BF are derived from surface Fc epsilon R and not from their intracellular precursors.
Identification of a surface antigen on Loa loa microfilariae the recognition of which correlates with the amicrofilaremic state in man.
Authors: Pinder M , Dupont A , Egwang T G
Published: December 2022

Filarial infections induce a spectrum of disease in their natural hosts, and by correlating immunity found in individuals with their disease pattern, one may delineate non-pathogenic, protective mechanisms. Loa loa is causal of mild to moderate pathology, and it is unique among the human filaria in that adult worms are occasionally visible during subconjunctival migration. To study immune mechanisms controlling microfilaremia, sera from 15 subjects with amicrofilaremic occult loiasis (OL) were compared with sera from 10 subjects with microfilaremic loiasis (ML) microfilaremia, (greater than 4000/ml) for their reactions with living microfilariae (mf). An IFA was first used to detect antibodies able to bind to the surface of living L. loa mf. ML subjects either did not react (7/10) or reacted only very weakly (3/10). Highly reactive sera were found only in OL subjects; 7/15 gave very bright fluorescence, 5/15 gave moderate reactions, and 3/15 were negative. Most of these antibodies were of the IgG class. Sera from all subjects were also reacted with living mf in an antibody-dependent cellular adherence test using normal leukocytes. Sera that were strongly positive in IFA showed strong adherence and IFA-negative sera were non-reactive. To identify the Ag involved, mf were surface iodinated, detergent-extracted Ag were immunoprecipitated, and Mr was determined on SDS-PAGE. Several OL sera, all highly reactive in the above tests, precipitated a 23-kDa molecule with which all ML sea failed to react. Sera from a mandrill experimentally infected with L. loa also precipitated the 23-kDa Ag when taken post-patency. In conclusion, it appears that certain people who control L. loa microfilaremia have high levels of IgG antibodies that bind to a surface Ag of 23 kDa and are able to mediate cellular adherence.
Effect of gamma radiation on resting B lymphocytes. II. Functional characterization of the antigen-presentation defect.
Authors: Ashwell J D , Jenkins M K , Schwartz R H
Published: December 2022

The effect of radiation on three discrete Ag-presentation functions in resting B cells was examined: 1) Ag uptake and processing, 2) expression of processed Ag in the context of functional class II molecules, and 3) provision of necessary co-stimulatory, or "second," signals. Analysis of radiation's effect on B cell presentation of intact vs fragmented Ag or its effect on presentation by Ag-pulsed B cells indicated that damage to Ag uptake and processing could not account for the bulk of the radiation-induced Ag-presentation defect. Experiments with phosphatidylinositol hydrolysis as an indirect measure of TCR occupancy suggested that irradiation caused a fairly rapid (within 1 to 2 h) decrease in the ability of the B cell APC to display a stimulatory combination of Ag and class II molecule. Ag dose-response analyses demonstrated that when presenting a fragment of the Ag pigeon cytochrome c to a T cell clone, 3000 rad-treated B cell APC were able to stimulate approximately 50% as much phosphatidylinositol turnover as unirradiated B cells. It was also found that, in contrast to their inability to initiate T cell proliferation, and similarly to chemically cross-linked splenocytes, heavily irradiated resting B cells plus Ag induced a state of Ag hyporesponsiveness in T cell clones. This effect on T cells had the same Ag- and MHC-specificity as did receptor occupancy required for proliferation, indicating that heavily irradiated resting B cells bear functional class II molecules. Co-culture of T cells with allogeneic B cells and syngeneic heavily irradiated B cells or chemically cross-linked splenic APC plus Ag resulted in T cell proliferation and interfered with the induction of the hyporesponsive state. This co-stimulatory function was radiosensitive in resting allogeneic B cells. Together, these data support the hypothesis that the major functional consequences of radiation to resting B cell APC are a reduction in the effective display of Ag plus class II molecules and, probably what is more important, a loss in the ability to provide APC-derived co-stimulatory signals.
BP-3 alloantigen. A cell surface glycoprotein that marks early B lineage cells and mature myeloid lineage cells in mice.
Authors: McNagny K M , Cazenave P A , Cooper M D
Published: December 2022

To explore the cell surface molecules expressed on pre-B cells we have produced a panel of alloantibodies against transformed pre-B cells from BALB/c mice by immunizing a wild mouse, Mus spretus. One of these antibodies, BP-3, recognized glycoproteins of Mr 38,000 to 48,000 on pre-B cells transformed either by the Abelson murine leukemia virus or an erb B oncogene construct. Removal of N-linked oligosaccharides from the BP-3 Ag revealed a single core protein of Mr 32,000. The Ag was expressed by bone marrow cells in all but one (A/J) of the inbred mouse strains tested and in wild mice of biochemical groups Mus-1 and Mus-2. Analysis of the tissue distribution revealed expression of the BP-3 reactive molecule on normal pre-B and B cells in the bone marrow, 35% of B cells in the circulation, 30% of the B cells in the spleen, and less than or equal to 20% of B cells in lymph nodes, peritoneal cavity, and Peyer's patches. The subpopulation of BP-3+ B cells in bone marrow and peripheral tissues displayed an immature phenotype (IgM IgD +/- ). Examination of a panel of transformed B lineage cells confirmed the early stage-specific expression of the BP-3 alloantigen. In addition, a myeloid cell line and normal myeloid cells were found to express the BP-3 alloantigen. In contrast to B lineage cells, the level of BP-3 expression increased as a function of myeloid cell differentiation. Myeloid cells in the bone marrow expressed relatively little Ag, whereas circulating neutrophils and peritoneal macrophages expressed relatively high levels of the BP-3 alloantigen with Mr 38,000, 41,000, and 46,000. The data suggest that this variably glycosylated cell surface protein could play different roles in the differentiation of B lineage and myeloid lineage cells. The BP-3 alloantigen appears to be a useful marker for virgin B cells that have recently migrated from the bone marrow to the periphery.
Receptor-like nature of class I HLA: endocytosis via coated pits.
Authors: Dasgupta J D , Watkins S , Slayter H , Yunis E J
Published: December 2022

The present investigations show that class I HLA are internalized by macrophage/monocyte type cells. Anti-class I antibody-binding assays show that about 30% of class I Ag present on cell surface are endocytosed within 1 h. Electronmicroscopic investigations reveal that, like other well established receptor molecules, internalization of HLA is mediated by coated pits and coated vesicles. The endocytosed Ag are transferred from endosomes to trans-Golgi reticulum and trans-Golgi cisternae, suggesting recycling of these Ag back to the cell surface. In the presence of phorbol ester tetradecanoyl phorbol acetate, there is a modest increase in the rate of internalization. These results are consistent with the hypothesis that class I Ag on monocytes/macrophages behave like receptor molecules. Malignant transformation of monocytic cells apparently causes the loss of this property of class I Ag.
Role of lymphokine-activated killer cells as mediators of veto and natural suppression.
Authors: Azuma E , Kaplan J
Published: December 2022

Fresh bone marrow cells have veto activity but little if any NK activity. By contrast, lymphokine-activated bone marrow cells have potent natural suppressor as well as veto activity, and also have cytolytic activity characteristic of lymphokine-activated killer cells. Veto activity of fresh bone marrow cells is eliminated by 9 Gy irradiation and by depletion of cells expressing Qa-2, but is unaffected by removal of cells expressing Thy-1, Qa-5, Ly-5, or asialo GM1. By contrast, the veto and NS activities of lymphokine-activated bone marrow cells are both abrogated by C lysis depletion of cells expressing Qa-2, Qa-5, Thy-1, asialo GM1, NK1, and Ly-11, but are unaffected by depletion of cells expressing Ly-2. Bone marrow cells depleted of Qa2+ cells fail to generate veto or natural suppressor activity when cultured in Con A-conditioned medium, unlike bone marrow cells depleted of mature NK1.1+ NK cells. Cloned NK cell line F8 is able to mediate both natural suppression and veto. These findings indicate that bone marrow veto and natural suppression are not mediated by T or NK cells present de novo in the bone marrow, but are dependent on proliferating cells that phenotypically resemble pre-NK cells. The progeny of these cells have the phenotype and functional activity of lymphokine-activated killer cells, and are capable of directly mediating both veto and natural suppression.
Booster irradiation to the spleen following total body irradiation. A new immunosuppressive approach for allogeneic bone marrow transplantation.
Authors: Lapidot T , Singer T S , Salomon O , Terenzi A , Schwartz E , Reisner Y
Published: December 2022

Graft rejection presents a major obstacle for transplantation of T cell-depleted bone marrow in HLA-mismatched patients. In a primate model, after conditioning exactly as for leukemia patients, it was shown that over 99% of the residual host clonable T cells are concentrated in the spleen on day 5 after completion of cytoreduction. We have now corroborated these findings in a mouse model. After 9-Gy total body irradiation (TBI), the total number of Thy-1.2+ cells in the spleen reaches a peak between days 3 and 4 after TBI. The T cell population is composed of both L3T4 (helper) and Lyt-2 (suppressor) T cells, the former being the major subpopulation. Specific booster irradiation to the spleen (5 Gy twice) on days 2 and 4 after TBI greatly enhances production of donor-type chimera after transplantation of T cell-depleted allogeneic bone marrow. Similar enhancement can be achieved by splenectomy on day 3 or 4 after TBI but not if splenectomy is performed 1 day before TBI or 1 day after TBI, strengthening the hypothesis that, after lethal TBI in mice, the remaining host T cells migrate from the periphery to the spleen. These results suggest that a delayed booster irradiation to the spleen may be beneficial as an additional immunosuppressive agent in the conditioning of leukemia patients, in order to reduce the incidence of bone marrow allograft rejection.
Adoptive T cell transfer of autoimmune nonobese diabetic mouse diabetes does not require recruitment of host B lymphocytes.
Authors: Bendelac A , Boitard C , Bedossa P , Bazin H , Bach J F , Carnaud C
Published: December 2022

The autoimmune nonobese diabetic mouse, a model of human juvenile type I diabetes mellitus, exhibits features of both B and T cell autoreactivity against insulin-producing cells. Using the neonatal cell transfer model of the disease, which we have described previously, we have shown that B cell suppression of newborn recipients by anti-mu treatment did not affect the transfer of diabetes by means of T cells. B cell-depleted, purified T cells from diabetic adults were injected into newborns treated with either IR-52, a control rat myeloma protein, or LOMM.9, a rat anti-mouse mu-chain mAb. Both groups developed diabetes over a similar time scale. Although the pancreases in both groups showed massive infiltration by T lymphocytes, B lymphocytes, presumably recruited in the host, were present in the IR-52-treated group, whereas they were absent in the LOMM.9-treated group. Anti-mu-treated diabetic animals showed substantial B cell suppression in vivo and in vitro when compared with IR-52-treated controls. These results suggest that B cell autoreactivity is a secondary phenomenon that is unimportant during the effector phase of diabetes in nonobese diabetic mice.
The antigen-binding T cell factor PCl-F sensitizes mast cells for in vitro release of serotonin. Comparison with monoclonal IgE antibody.
Authors: Meade R , Van Lovern H , Parmentier H , Iverson G M , Askenase P W
Published: December 2022

Picryl chloride factor (PC1-F) is an antigen (TNP hapten)-binding T cell factor that initiates PC1 contact sensitivity (CS). PC1-F initiates PC1 CS by mediating an early 2-h skin swelling reaction that is due to local release of the vasoactive amine serotonin (5-HT) by mast cells, and perhaps other 5-HT-containing cells. Experiments were conducted to determine if PC1-F could sensitize normal mast cells in vitro for subsequent release of 3H-5-HT that had been taken up previously. It was found that PC1-F could sensitize mast cells, inasmuch as incubation with PC1-F, followed by washing, resulted in the ability to release 5-HT by challenge with Ag (TNP-bovine serum albumin), or by an anti-factor mAb called 14-30. As with release induced by anti-TNP IgE mAb PC1-F-induced release required phosphatidyl serine. Mast cell sensitization and activation for 5-HT release by PC1-F was not due to contamination of PC1-F with IgE antibody, because IgE (and not PC1-F) was sensitive to reduction and alkylation. Also, affinity columns linked with 14-30 or anti-IgE showed that the mast cell sensitizing and activating property of PC1-F was clearly separate from that of IgE. PC1-F-induced release was not IgE dependent, because mast cells that were acid-stripped and largely depleted of surface IgE, could then be sensitized by PC1-F. In vivo experiments demonstrated that local challenge with 14-30 antibody induced a 2-h ear swelling reaction in actively contact sensitized mice, or adoptive recipients of sensitized cells, and in normal mice that received PC1-F i.v. These findings suggest that in vitro sensitization of mast cells with PC1-F, and subsequent in vitro release of 5-HT induced by challenge with 14-30 antibodies, correlates with the initiation of PC1 CS in vivo. Therefore, in the initiation of CS by PC1-F, mast cells can be one source of 5-HT, to cause the early, vasoactive phase of CS.
Intrinsic resistance to viral infection. Mouse macrophage restriction of herpes simplex virus replication.
Authors: Sarmiento M
Published: December 2022

Macrophages isolated from mice resistant to acute (lethal) infection with a neurovirulent isolate of HSV-1 express intrinsic resistance to viral infection in vitro. Bone marrow (BM), spleen (S), peritoneal (P), and thioglycolate-stimulated peritoneal (Pthio) macrophages isolated from resistant C57BL/6 Cr (B6) mice consistently restrict HSV-1 macromolecular synthesis earlier in the viral replicative cycle than do macrophages isolated from the same tissue sources from more susceptible DBA/2Cr (D2) mice. B6-BM (BM macrophages from B6 mice) restrict HSV macromolecular synthesis at least at two points in the replicative cycle: 1) before the onset of alpha-protein synthesis and 2) between the onset of gamma 1 protein and DNA synthesis. D2-BM macrophages restrict HSV replication at about the time of DNA synthesis. B6-P macrophages restrict HSV replication shortly after gamma 1 protein synthesis, and D2-P macrophages inhibit the virus slightly later, but before DNA synthesis. B6-S macrophages restrict HSV replication at about the time of DNA synthesis, and D2-S macrophages inhibit replication after the onset of gamma 2 protein synthesis. Pthio macrophages are more permissive to HSV infection than BM, P, or S macrophages: restrictions in viral replication occur at the time of DNA synthesis in B6-Pthio macrophages, and after the onset of gamma 2 protein synthesis in D2-Pthio cells. These studies demonstrate that isolated macrophages from inbred mouse strains express intrinsic resistance to HSV infection that correlates with in vivo resistance to acute (lethal) infection. Intrinsic resistance to HSV-1 infection is due to restriction of viral macromolecular synthesis. HSV replication is inhibited in macrophages at multiple points in the viral growth cycle, depending on the tissue from which the cells are isolated.
Tryptophan degradation in transplanted tumor cells undergoing rejection.
Authors: Yoshida R , Park S W , Yasui H , Takikawa O
Published: December 2022

The depletion of an essential amino acid, tryptophan, caused by indoleamine 2,3-dioxygenase induction in vitro, has been shown to be due to a mechanism that is used in self-defense against inhaled microorganisms and tumor growth. In this communication, we report the results of measuring dioxygenase activity in the peritoneal exudate cells and tumor cytotoxicity at the transplantation loci after in vivo transplantation of tumor cells into the peritoneal cavity of syngeneic or allogeneic strains of mice. The enzyme was induced only when the tumor cells were being rejected from allogeneic animals and no change was observed when the cells continued to grow in syngeneic animals. Furthermore, when the syngeneic tumor cells in a diffusion chamber were i.p. transplanted simultaneously with i.p. injection of allogeneic tumor cells, the enzyme was induced not only in allografted tumor cells but also in the syngeneic tumor cells. Under these conditions, the tumor cells in the diffusion chamber ceased to grow and 50% of the cells were rejected. To determine the type of cells containing the induced enzyme, the peritoneal exudate cells (tumor cells and host cells--mostly small lymphocytes) were separated into six fractions by sedimentation under gravity and by differential centrifugation. Approximately 80% of total enzyme activity was localized in a tumor-rich fraction (98.9% purity), whereas only 0.2% of the activity was found in a lymphocyte-rich fraction (99.5% purity). The localization of indoleamine 2,3-dioxygenase in the tumor cells was confirmed by complement-dependent lysis with specific antibodies against tumor and host cells.