bluuebunny/crossref_metadata_2025 huggingface dataset:
The antigenic interrelationship between the endoflagella of Treponema phagedenis biotype Reiter and Treponema pallidum Nichols strain. I. Treponemicidal activity of cross-reactive endoflagellar antibodies against T. pallidum.
Authors: Blanco D R , Radolf J D , Lovett M A , Miller J N
Published: December 2022

Treponemicidal activity against Treponema pallidum, Nichols strain, by anti-endoflagellar antibodies and the presence of antigenic interrelationships between the endoflagella of Treponema phagedenis biotype Reiter (TPR) and T. pallidum have been demonstrated. SDS-PAGE profiles of purified endoflagella from both organisms were similar, identifying five polypeptide bands for TPR (37,000, 33,000 doublet, 30,000, and 27,000 daltons) and five polypeptide bands for T. pallidum (35,000, 33,000 doublet, 30,000, and 27,000 daltons). Antiserum against TPR endoflagella identified identical bands on Western blots of TPR, T. pallidum, and the respective endoflagellar preparations. Western blots confirmed the presence of antibodies in normal human serum (NHS) against the 33,000 dalton treponemal endoflagellar proteins. The complement-dependent treponemicidal activity of NHS against T. pallidum was completely removed by absorption with purified TPR endoflagella. Furthermore, rabbit antisera against TPR endoflagella were reactive in the Treponema pallidum immobilization (TPI) test. These findings demonstrate that anti-endoflagellar antibodies are treponemicidal against T. pallidum. A possible mechanism for this activity is discussed in relation to the subsurface location of endoflagella.
Growth inhibition of Candida albicans by human polymorphonuclear neutrophils: activation by interferon-gamma and tumor necrosis factor.
Authors: Djeu J Y , Blanchard D K , Halkias D , Friedman H
Published: December 2022

This study was designed to determine whether anti-fungal activity in human polymorphonuclear neutrophils (PMN) might be under the regulation of cytokines such as tumor necrosis factor (TNF) and interferon-gamma (IFN-gamma). By using a radiolabel microassay developed in our laboratory that makes use of the incorporation of [3H]glucose into residual candida, we demonstrated that PMN were better able to inhibit Candida albicans growth in vitro than peripheral blood lymphocytes (PBL). PMN from normal volunteers added to C. albicans for 24 hr at 37 degrees C in a 96-well microplate inhibited fungal growth almost completely at the 300:1 effector/target ratio and frequently at 100:1. Significant activity was still detected at 10:1. In contrast, PBL from the same donors had less activity than PMN at all the ratios tested and lost all function at the 30:1 ratio. TNF and IFN-gamma added to the PMN/candida cultures additionally enhanced PMN to inhibit candida growth. Both cytokines effectively activated PMN down to 0.1 to 0.01 U/ml, and neither cytokine interfered directly with fungal growth, even up to 1000 U/ml. Concentrations of TNF and IFN-gamma below the level that enhanced PMN function when added together to PMN acted synergistically to significantly enhance their anti-fungal activity. Therefore, TNF and IFN-gamma which are active on lymphoid cells, also appear to have the ability to directly activate PMN, and the synergistic action of the two cytokines at low doses that may be below the toxic range may prove to be of clinical importance in protection of immunocompromised host against opportunistic infections.
Synergistic antitumor effect of interferon and anti-idiotype monoclonal antibody in murine lymphoma.
Authors: Basham T Y , Kaminski M S , Kitamura K , Levy R , Merigan T C
Published: December 2022

Both IFN-alpha and anti-idiotype monoclonal antibody therapy have significant antitumor activity in vivo in a murine B cell lymphoma model. Combination therapy with syngeneic anti-idiotype antibody of the IgG2a or IgG2b isotype (a single i.p. injection of 100 micrograms) and recombinant human hybrid interferon-alpha A/D (10(4) to 10(6) U three times weekly for 3 wk) synergistically increased median survival time in mice challenged with a lethal dose of tumor cells compared with the sum of the median survival times of the two individual treatments. IFN-alpha has direct antiproliferative activity against 38C13 in vitro and enhances in vitro macrophage anti-idiotype antibody-specific cytolysis for IgG2a, IgG2b, and IgG1 isotypes.
Relationship among function, phenotype, and specificity in primary allospecific T cell populations: identification of phenotypically identical but functionally distinct primary T cell subsets that differ in their recognition of MHC class I and class II allodeterminants.
Authors: Golding H , Mizuochi T , McCarthy S A , Cleveland C A , Singer A
Published: December 2022

The goal of the present study was to evaluate the relationship among function, Lyt phenotype, and MHC recognition specificity in primary allospecific T cell populations. By using Lyt-2+ and L3T4+ T cells obtained from the same responder populations, we assessed the ability of T cells of each phenotype to generate cytotoxic effector cells (CTL) and IL 2-secreting helper T cells in response to either class I or class II MHC allodeterminants. It was found that a discordance between Lyt phenotype and MHC recognition specificity does exist in primary allospecific T cells, but only in one T cell subpopulation with limited functional potential: namely, Lyt-2+ T cells with cytotoxic, but not helper, function that recognize class II MHC alloantigens. Target cell lysis by these Lyt-2+ class II-allospecific CTL was inhibited by anti-Ia monoclonal antibodies (mAb), but not anti-Lyt-2 mAb, indicating that they recognized class II MHC determinants as their "restriction" specificity and not as their "nominal" specificity even though they were Lyt-2+. A second allospecific T cell subset with limited functional potential was also identified but whose Lyt phenotype and MHC restriction specificity were not discordant: namely, an L3T4+ T cell subset with helper, but not cytotoxic, function specific for class I MHC allodeterminants presented in the context of self-Ia. Thus, the present study demonstrates that primary allospecific T cell populations contain phenotypically identical subpopulations of helper and effector cells that express fundamentally different MHC recognition specificities. Because the recognition specificities expressed by mature T cells reflect the selection pressures they encountered during their differentiation into functional competence, these findings suggest that functionally distinct but phenotypically identical T cell subsets may be selected independently of one another during ontogeny. Thus, the existence of Lyt-2+ CTL specific for class II allodeterminants can be explained by the hypothesis that the association of Lyt phenotype with MHC recognition specificity results from the process of thymic selection that these Lyt-2+ effector cells avoid.
Human monoclonal anti-T cell antibody from a patient with juvenile rheumatoid arthritis.
Authors: Alpert S D , Turek P J , Foung S K , Engleman E G
Published: December 2022

Antibody JRAI is a human monoclonal IgM antibody derived from a patient with juvenile rheumatoid arthritis that is cytotoxic to a subpopulation of normal T lymphocytes. JRAI recognizes approximately 80% of normal peripheral blood T cells, 90% of CD4+ cells, and 75% of CD8+ cells, as determined by complement-mediated cytotoxicity. Within the CD8+ population, JRAI preferentially spares OKM1+ and Leu-11+ cells. These CD8+ cells retain suppressor-effector potential and show enriched natural killer cell activity. Within the CD4+ population, JRAI preferentially kills cells within the Leu-8+ subset, which contains suppressor-inducer cells, and spares the Leu-8- subset, which contains the helpers for immunoglobulin synthesis. JRAI appears to recognize a previously undefined human lymphocyte surface molecule expressed differentially on phenotypically and functionally distinct subsets of human T cells.
HLA-linked nonresponsiveness to Cryptomeria japonica pollen antigen. I. Nonresponsiveness is mediated by antigen-specific suppressor T cell.
Authors: Matsushita S , Muto M , Suemura M , Saito Y , Sasazuki T
Published: December 2022

The objective of this study was to elucidate the cellular mechanism of IgE nonresponse to the Cryptomeria japonica (Japanese cedar) pollen antigen (CPAg), which was shown in our previous study to be HLA-linked (1). We established an assay system for the measurement of small amounts of anti-CPAg IgE antibody, both in an antigen-specific and isotype-specific manner, and a culture system to induce antigen-driven IgE antibody synthesis in vitro. By using these methods, we clarified that the function of the HLA-DR molecule in the CPAg-driven IgE response is similar to that of I-A or I-E molecule in mice, namely the product of immune response genes (Ir-genes), because anti-HLA-DR monoclonal antibody blocked the response, and the interaction between monocyte and monocyte-depleted peripheral blood lymphocytes (PBL) to respond to CPAg was restricted by HLA-DR. Furthermore, PBL from nonresponders revealed a specific IgE response to CPAg when the Leu-2+3- T cell fraction was depleted, thereby suggesting that even nonresponders have Leu-2-3+ T cell and B cell clones specific for CPAg, and they apparently show no response due to the presence of CPAg-specific Leu-2+3- suppressor T cells. This suppressor T cell fraction abolished the IgE response of the autologous B + monocyte + Leu-2-3+ T cell in a CPAg-specific manner. The current cellular analysis together with our previous genetic analysis strongly suggest that the HLA-linked IgE nonresponse to CPAg is mediated by CPAg-specific suppressor T cells. The HLA-linked gene controlling the nonresponsiveness to CPAg is thus designated as the immune suppression gene for CPAg (Is-CPAg). Mapping of Is-CPAg within HLA-DQ subregion is discussed.
The NZB X SWR model of lupus nephritis. II. Autoantibodies deposited in renal lesions show a distinctive and restricted idiotypic diversity.
Authors: Gavalchin J , Datta S K
Published: December 2022

The F1 progeny (SNF1) derived from crossing autoimmune NZB with normal SWR mice uniformly develop lethal glomerulonephritis in marked contrast to the NZB parents. In the preceding paper we found qualitative and idiotypic differences between the anti-DNA antibodies produced by the SNF1 mice and their NZB parents. We identified two clusters of interrelated cross-reactive idiotypic (CRI) families among the SNF1-derived autoantibodies. Here we analyzed the idiotypic profile of the broad spectrum of immunoglobulins deposited in the nephritic kidneys of SNF1 mice and found a restricted idiotypic diversity. To establish that the autoantibody idiotypes detected in the renal lesions were not there as a result of nonspecific trapping, five separate batches of kidney eluates obtained from 100 SNF1 kidneys were analyzed. Both during early and late stages of nephritis, the predominant and consistent idiotypic markers of antibodies in the renal lesion of SNF1 mice were those shared by the two clusters of anti-DNA CRI families. We have termed these nephritogenic idiotypic markers collectively as idiotypes-lupus nephritis-SNF1 or IdLNF1. The Id564 family that encompasses a set of SNF1-derived highly cationic anti-DNA antibodies bearing the normal SWR parent's allotype was more prominently represented in the SNF1 kidneys with early nephritis. Although cationic antibodies were prevalent, the IdLNF1 markers were present on both cationic and anionic or neutral antibodies in the renal lesions of SNF1 mice, and the Ig allotypes of both parents were equally represented in those nephritogenic antibodies. The IdLNF1 positive family of antibodies were also found in high levels in the sera of old SNF1 mice, but they could not be detected in the sera of NZB or SWR mice, nor were they present in the immunoglobulins deposited in the kidneys of rare old NZB mice. The results suggest that select families of nephritogenic idiotypes that are dormant in the autoimmune NZB and the normal SWR parents become expressed in the SNF1 progeny due to genetic and immunoregulatory defects.
Identification of IL 2R+ T cells and macrophages within rejecting rat cardiac allografts, and comparison of the effects of treatment with anti-IL 2R monoclonal antibody or cyclosporin.
Authors: Hancock W W , Lord R H , Colby A J , Diamantstein T , Rickles F R , Dijkstra C , Hogg N , Tilney N L
Published: December 2022

Monoclonal antibodies to lymphokine-induced activation antigens of lymphocytes and macrophages were used to analyze the intragraft events occurring during acute rejection of rat heterotopic cardiac allografts. The cells present during untreated rejection were then compared with those present in situ after immunosuppression with the mouse anti-rat IL 2 receptor (anti-IL 2R) monoclonal antibody ART-18 or cyclosporin (CsA). Untreated rats rejected their grafts within 7 days, whereas rats receiving 10 days of i.v. ART-18 antibody therapy showed graft prolongation to more than 21 days, and rats receiving CsA for 7 days maintained their grafts indefinitely. Untreated rejection was associated with an influx of T (W3/13+) cells and macrophages (ED-1+, ED-2+). Activated mononuclear cells (IL 2R+) were identified within rejecting grafts from day 2, and their numbers peaked on days 4 to 6 when 15 to 20% of infiltrating leukocytes were IL 2R+. Double labeling studies of IL 2R+ cells present at day 6 showed surprisingly that both T cells and macrophages expressed IL 2R. In particular, although 55.8 +/- 6.9% (mean +/- SD) of IL 2R+ cells expressed the pan-T cell antigen 3/13, a similar proportion of IL 2R+ cells (49.8 +/- 8.2%) expressed the macrophage antigen ED-2. Conversely, both T cells and macrophage populations showed heterogeneity in their expression of IL 2R, because 39.2 +/- 12.2% of T cells and 31.0 +/- 13.4% of macrophages were IL 2R+. In addition, inflammatory macrophages at day 6 expressed the A1-3 antigen. Expression of this antigen by macrophages has previously been linked with development of macrophage procoagulant activity, and in this model intragraft inflammatory macrophages were closely associated with widespread deposits of fibrin. By comparison with untreated animals, rats treated with either ART-18 or CsA both lacked detectable IL 2R+ cells during the first 14 days post-transplantation (post-Tx), and showed significantly less cellular infiltration. However, although grafts of CsA-treated animals continued to remain IL 2R- and failed to stain with the macrophage activation marker A1-3, ART-18-treated rats showed increasing infiltration by both IL 2R+ mononuclear cells and A1-3+ macrophages, as well as increasing perivascular and interstitial fibrin deposition, prior to rejection by day 22. These studies document the presence of small number of activated intragraft T cells and macrophages during rat cardiac rejection, and show how CsA, and to a lesser extent anti-IL 2R therapy, inhibit this in situ activation and prolong graft survival. (ABSTRACT TRUNCATED AT 400 WORDS)
Use of the monoclonal antibody 12F1 to characterize the differentiation antigen VLA-2.
Authors: Pischel K D , Hemler M E , Huang C , Bluestein H G , Woods V L
Published: December 2022

A monoclonal antibody, 12F1, has been produced that specifically immunoprecipitates the human cell surface structure VLA-2 from platelets and long-term activated T cells, as well as from fibroblast and neuroblastoma cell lines. Cross-linking studies indicate that the VLA-2 structure exists on the cell surface as a 165,000 Mr heavy chain (alpha 2) in noncovalent 1:1 association with a 130,000 Mr light chain (beta). The monoclonal antibody A-1A5, which reacts with the beta subunit common to all VLA structures, was able to completely preclear VLA-2, indicating that all of the alpha 2 subunit was associated with VLA beta-chain. The specificity of 12F1 for VLA-2 allowed independent immunoprecipitation and flow cytometry analysis of this alpha 2 beta structure separate from any other VLA structures that may have been present such as VLA-1 or free beta-subunit. Subunit dissociation studies were used to demonstrate that 12F1 recognizes an epitope on the alpha 2 chain on VLA-2, which is consistent with the 12F1 specificity for VLA-2 alone among the VLA proteins. Analysis of activated T cells indicated that VLA-2, like VLA-1, is another "very late" appearing T cell activation antigen that arises concurrently with VLA-1 starting at day 7 and increasing through 2 wk. VLA-2 was found on many of the same cells as VLA-1 (inactivated T cells, T cell leukemia cells, fibroblasts, SK-N-SH neuroblastoma cells), but VLA-1 and VLA-2 can be expressed independently, because VLA-2 was also present on VLA-1-negative cells such as HSB and platelets, and VLA-1 was present on VLA-2-negative C8215 cells.
Interleukin 1 releases histamine from human basophils and mast cells in vitro.
Authors: Subramanian N , Bray M A
Published: December 2022

Interleukin (IL 1) preparations from five different sources (human monocyte, LPS-stimulated, purified IL 1 from two different laboratories) and human recombinant IL 1 (HrIL 1) were shown to be capable of directly inducing histamine (HA) release from human basophils (10 to 50% of total cellular HA, depending on the source of IL 1). The release was not due to the medium, pyrogens, or other contaminants. Il 1-induced HA release was dose dependent between 1 to 100 U/ml of IL 1 and 1 to 15 ng/ml of HrIL 1 and was rapid, with a peak release at 15 min. HA release induced by IL 1 was blocked completely by preexposure of cells to IL 1 but was not affected by prechallenge with anti-IgE. Also, preincubation of IL 1 with anti-IL 1 antibody abolished the HA-releasing activity. IL 1-induced HA release was also observed in preparations of human adenoidal mast cells. Our data indicate that it is unlikely that the HA release induced by IL 1 is due to a contamination with HA-releasing factor. This effect of IL 1 provides a mechanism for non-IgE-related local HA release and raises the possibility of a link between cellular immunity and immediate hypersensitivity of potential importance for the pathology of immuno/inflammatory diseases.
Aging and lymphocyte cytoskeleton: age-related decline in the state of actin polymerization in T lymphocytes from Fischer F344 rats.
Authors: Cheung H T , Rehwaldt C A , Twu J S , Liao N S , Richardson A
Published: December 2022

T cell functions are known to decline with age, but the underlying cause of the decline is unclear. Because of the importance of cytoskeletal elements in cellular functions, we examined the content and the state of polymerization of actin in lymphocytes from Fischer F344 rats of four different ages (6, 14, 23, and 31 mo). The cellular actin content was determined by a DNAase I inhibition assay. Our results indicate that the total actin content of spleen lymphocytes did not change significantly with age; however, polymeric actin content, particularly in T cells, decreased with age, which might be a result of the shift from the polymeric actin pool to the monomeric pool. Similar changes also occurred in B cells but to a lesser extent. We conclude that the state of polymerization of lymphocytes changed drastically with age, and that this might be an important factor in the age-related decline in the cellular functions of lymphocytes.
Expression of a recombinant murine IgE in transfected myeloma cells.
Authors: Gritzmacher C A , Liu F T
Published: December 2022

We constructed a recombinant gene encoding an immunoglobulin (Ig) heavy chain consisting of the variable region from the phosphorylcholine (PC)-specific secreting myeloma MOPC167 and the epsilon constant region from SJL mice. This gene, cloned into the shuttle vector pSV2gpt, was transfected into J558L myeloma cells, and stable transformants that expressed the epsilon gene were cloned. The IgE heavy chain in these transformants is associated with the endogenous lambda light chain and is secreted as an intact IgE molecule. However, the secreted IgE does not bind to PC conjugated to bovine serum albumin (PC-BSA). The MOPC167 kappa chain gene was cloned into the shuttle vector pSV2neo and was transfected into the epsilon heavy-chain transformant. Stable transformants were cloned that expressed both the epsilon heavy chain and the kappa light chain. IgE secreted from such a transformant was shown to bind to PC-BSA. Both types of secreted recombinant IgE bound to rat basophilic leukemia (RBL) cells, but only the IgE produced by the cell line transformed with the MOPC167 kappa gene could be cross-linked with PC-BSA to cause serotonin release.
Antigen-presenting T cells. II. Clonal responses of alloreactive and virus-specific self-restricted human cytotoxic T cell responses stimulated by T lymphoblasts.
Authors: Kabelitz D , Enssle K H , Fleischer B , Reimann J
Published: December 2022

The capacity of various stimulator cell types to present alloantigens or viral antigens to resting human CD8+ cytotoxic lymphocyte precursors (CLP) was analyzed in a limiting dilution culture system. Cell sorter-separated T lymphoblasts of both CD4+ and CD8+ phenotypes but not resting T cells were found to efficiently stimulate the clonal development of allogeneic CD8+ CLP. Thus, 5000 CD4+ T lymphoblasts activated as many (one out of 200 to one out of 300) allogeneic CLP as 50,000 peripheral blood mononuclear stimulator cells. This potent stimulator activity was found in CD4+ and CD8+ T lymphoblasts activated by mitogen, anti-T3 monoclonal antibody, or mixed leukocyte reactions. Cytotoxic T cells generated in this system were highly specific for HLA class I antigens. Furthermore, T lymphoblasts infected with mumps virus efficiently induced development of autologous CLP into CTL clones that were virus specific and self-HLA restricted, as shown by split-well analysis. The possible in vivo significance of antigen-presenting T lymphoblasts is discussed.
HLA class II restriction of T helper cell response to cytomegalovirus (CMV). I. Immunogenetic control of restriction.
Authors: Gehrz R C , Fuad S , Liu Y N , Bach F H
Published: December 2022

All three HLA class II families (DR, DQ, and DP) are involved in restriction of helper T cell (Th) recognition of nominal antigens including CMV. Only limited studies have been described previously to determine whether restricting determinants of DR and especially DQ are subtypic to the serologically defined DR and DQ specificities, and to what extent restricting determinants are associated with Dw specificities defined in alloresponses. In the present report, we describe a large number of CMV-specific Th clones derived from two different individuals who are seropositive for CMV. Clones were classified as being DR-, DQ-, or DP-reactive based on blocking with monoclonal antibodies. DR- and DQ-restricted clones were then examined in panel studies using antigen-presenting cells (APC) expressing the Dw subtype of the restricting DR-DQ haplotype, as well as APC expressing different Dw subtypes associated with the serologically defined specificity. Unrelated specificities were also included. Our findings show that not only for DR but for DQ as well, the primary restricting determinants appear to be subtypic to the serologically defined antigen; furthermore, subtype restriction for both DR and DQ is very closely associated with single Dw specificities. In several cases in which cross-reactivity among restricting Dw specificities was observed in association with a given DR or DQ haplotype, a molecular basis could be suggested to explain the cross-reacting determinants. A small minority of the clones appeared to be CMV specific, but was restricted by a determinant(s) that is either monomorphic or minimally polymorphic.
Antibody-induced association between discrete regions of HLA class I and II antigens.
Authors: Russo C , Nepo A , Lanza E , Igarashi M , Ferrone S
Published: December 2022

The anti-HLA-DR + DP monoclonal antibody (MoAb) CR11-462 was unexpectedly found to cross-inhibit the binding to B lymphoid cells of the anti-HLA Class I MoAb CR10-215 and CR11-115. The latter two antibodies recognized the same or spatially close antigenic determinant. The cross-blocking of anti-HLA Class I MoAb CR10-215 and CR11-115 by MoAb CR11-462 reflects neither its contamination by anti-HLA Class I antibodies nor its cross-reactivity with HLA Class I antigens. On the other hand, the cross-blocking appears to reflect redistribution of HLA Class II antigens by the MoAb CR11-462, since the MoAb CR10-215 and CR11-115 are not susceptible to blocking when lymphoid cells are treated with 0.025% glutaraldehyde or are coated with Fab' fragments of the MoAb CR11-462. Furthermore, immunoprecipitates from B lymphoid cells preincubated with the MoAb CR11-462 before solubilization contain HLA Class I antigens. Therefore, these results have shown for the first time an antibody-induced association between discrete regions of HLA Class I and Class II antigens on the membrane of B lymphoid cells.
Effect of immunodeficiency on diabetogenesis in genetically diabetic (db/db) mice.
Authors: Leiter E H , Prochazka M , Shultz L D
Published: December 2022

The pathogenesis of diabetes in C57BL/KsJ-db/db mice has been proposed to entail autoimmune mechanisms. We have combined immunodeficiency genes with the db mutation to determine whether beta cell necrosis and establishment of severe diabetes would occur in the absence of normal T and/or B lymphocyte functions. Inbred mice carrying the recessive mutations, severe combined immunodeficiency (scid), X-linked immunodeficiency (xid), nude (nu), and the Y-linked autoimmune accelerator (Yaa), were crossed with strains congenic for the db mutation. The diabetes syndrome was studied in double homozygotes produced in the F2 generation. In another experiment, C57BL/KsJ-db/db males were made T cell function deficient by adolescent thymectomy followed by lethal irradiation and bone marrow reconstitution. None of these manipulations served to prevent the induction of a severe diabetes syndrome in any of the model systems analyzed. Thus, diabetogenesis characterized by massive necrosis of the pancreatic beta cells and atrophy of the pancreatic islets was observed in both the absence of normal T cell function (as assessed by absence of T cell mitogen response) and humoral autoimmunity against beta cell antigens (insulin, retroviral p73). In conclusion, our data indicate that anti-beta cell autoimmunity is not a primary event in the etiopathogenesis of diabetes in the db/db mouse.
Increased adhesion to fibronectin and Mo-1 expression by diabetic monocytes.
Authors: Setiadi H , Wautier J L , Courillon-Mallet A , Passa P , Caen J
Published: December 2022

As excessive monocyte adhesion to blood vessel wall could produce endothelial cell injury, we undertook comparative studies on the monocyte adhesiveness in insulin-dependent diabetics with vascular complications (n = 26) and healthy, normal subjects (n = 36). In the diabetic group, the extent of monocyte adhesion on fibronectin- and autologous plasma-coated surfaces was significantly increased compared with that in the control group (p less than 0.01 on both types of surfaces). Monocytes adhesion to the plasma-coated surface, but not to the fibronectin-coated surface, could be inhibited by monoclonal anti-Mo-1 antibody in a dose-dependent manner. For diabetic monocyte adhesion, a higher amount of anti-Mo-1 antibody was required to produce a similar extent of inhibition as observed with control monocytes. This indication of increased Mo-1 expression on diabetic monocytes was further confirmed by analyzing the fluorescence intensity of monocytes labeled with the antibody anti-Mo-1. The results of the present study suggest that diabetic monocytes have increased adhesiveness as the result of increased expression of fibronectin and Mo-1 receptors.
Retrovirus infection alters growth factor responses of T lymphocytes.
Authors: Lichtman A H , Williams M E , Ohara J , Paul W E , Faller D V , Abbas A K
Published: December 2022

A murine helper/inducer T cell clone, D10.G4, has been infected with Kirsten-murine sarcoma virus (KiSV) pseudotyped with an amphotropic murine leukemia virus. The resultant Ki-ras-expressing lines (KiSV-D10) remain dependent on exogenous factors for continued growth but display distinctly different mitotic responses to certain cytokines as compared to the uninfected parent clone. Unlike the parent D10.G4 cells, these KiSV-D10 cells can be maintained in vitro indefinitely in the presence of recombinant interleukin 2 (IL 2), and they all display a maximal proliferative response to purified or recombinant interleukin 1 (IL 1). The IL 1-induced proliferation is shown not to be dependent or secretion of the T cell autocrine growth factors IL 2 or B cell stimulatory factor-1 (BSF-1). The KiSV-D10 lines show certain differences from one another and parent D10.G4 cells in their secretory and proliferative responses to T cell receptor- and BSF-1 mediated signals. These viral oncogene-expressing T cell lines, which remain responsive to and dependent on physiologic growth factors, should prove valuable for analyzing the mechanisms of action of single oncogenes and the intracellular events in T lymphocyte activation.
Augmentation of IL 1-induced fibroblast PGE2 production by a urine-derived IL 1 inhibitor.
Authors: Korn J H , Brown K M , Downie E , Liao Z H , Rosenstreich D L
Published: December 2022

IL 1, a monocyte-derived cytokine, has potent biologic effects in a variety of target tissues. The existence of naturally occurring inhibitors of IL 1 activity has been recently described; these inhibitors blocked one IL 1 effect: stimulation of thymocyte responses to mitogens. We examined the effect of one well-characterized inhibitor of IL 1, isolated from the urine of febrile patients, on a second IL 1 effect, stimulation of fibroblast PGE synthesis. In this system, purified preparations of the urinary inhibitor that completely blocked murine thymocyte proliferative responses to mitogen failed to block PGE synthetic responses to IL 1. Rather, inhibitor preparations markedly enhanced fibroblast PGE synthetic responses to IL 1. When partially purified inhibitor preparations were fractionated by ion exchange chromatography, inhibitory activity for the IL 1 effect on thymocytes and PGE stimulatory activity co-eluted. Augmentation of the IL 1-induced PGE response was seen with both low (1:1 unit) and high (400:1) ratios of inhibitor to IL 1. Inhibitor preparations alone did not stimulate fibroblast PGE synthesis. The augmentation of fibroblast PGE synthesis by inhibitor preparations was not due to contaminating endotoxin. Active inhibitor preparations contained less than 15 pg of endotoxin/U activity, and the PGE stimulatory effect was not blocked by the addition of polymyxin B, whereas polymyxin B reversed the effects of exogenous endotoxin. It appears that the inhibition of IL 1 effects by naturally occurring inhibitors may have target cell and/or functional specificity.
Inhibitory activity of interleukin B on the suppressor T cell hybrid T2D4.
Authors: del Guercio P , del Guercio M F , Fridman W H , Katz D H
Published: December 2022

Interleukin B (IL-B), a product of unstimulated B cells, is defined by its ability to selectively prevent the differentiation of suppressor T lymphocytes from precursors into effectors. The present study was undertaken to determine whether IL-B could also be active in modulating the activity of the T cell hybrid T2D4, which produces immunoglobulin-binding suppressor factors. T2D4 cells can be selectively induced by incubation with various isotypes of antibody to express isotype-specific Fc receptors and to release soluble factors that suppress production of the corresponding isotype. The data presented here demonstrate that IL-B is greatly effective in inhibiting T2D4 activities. Either pretreatment with IL-B or continuous exposure to IL-B prevents isotype activation of T2D4. As a result, T2D4 cells do not express isotype receptors and do not produce detectable amounts of isotype-specific suppressor factors. This IL-B regulatory activity on T2D4 is temperature dependent and is inhibited by cytochalasin B. These findings provide new insights on the mechanism by which IL-B enhances antibody responses, and they offer a conceptual framework for analyzing IL-B activity on suppressor T cells.
Characterization of a keratinocyte-derived T cell growth factor distinct from interleukin 2 and B cell stimulatory factor 1.
Authors: Coleman D L , Kupper T S , Flood P M , Fultz C C , Horowitz M C
Published: December 2022

Epidermal epithelial cells (keratinocytes) produce and secrete a variety of immunologically active cytokines. We have previously reported that both transformed (PAM 212) and normal murine keratinocytes produce a soluble factor which induces proliferation of the T cell line, HT-2. In the present study we sought to compare keratinocyte-derived T cell growth factor (KTGF) with other T cell growth factors, characterize its physicochemical properties, and substantially purify KTGF from PAM 212 conditioned medium. KTGF from PAM 212 conditioned medium was not inhibited by antibodies which block the effect of interleukin 2 (IL 2) (S4B6) or B cell stimulatory factor 1 (BSF 1) (11B11). KTGF is heat-stable, has an isoelectric point of 4.8, and a relative molecular mass of 16 to 23 kilodaltons under nonreducing conditions. KTGF activity was enhanced at least 41,413-fold by sequential hydroxylapatite bulk preparation, desalting by reversed-phase chromatography, gel filtration high pressure liquid chromatography (HPLC), and reversed-phase HPLC. Keratinocytes produce a T cell growth factor with physicochemical properties distinct from IL 2 and BSF 1. KTGF may play a role in regulating the growth and differentiation of T cells in the epidermis.
Activation of cultured human endothelial cells by recombinant lymphotoxin: comparison with tumor necrosis factor and interleukin 1 species.
Authors: Pober J S , Lapierre L A , Stolpen A H , Brock T A , Springer T A , Fiers W , Bevilacqua M P , Mendrick D L , Gimbrone M A
Published: December 2022

Recombinant human lymphotoxin (LT) was compared with recombinant human tumor necrosis factor (TNF) for direct actions on cultured human endothelial cells (HEC). At equivalent half-maximal concentrations (based on L929 cytotoxicity units) LT and TNF each caused rapid and transient induction (peak 4 to 6 hr) of an antigen associated with leukocyte adhesion (detected by monoclonal antibody H4/18), a rapid but sustained increased expression (plateau 24 hr) of a lymphocyte adhesion structure (ICAM-1), a gradual (plateau 4 to 6 days) increase in expression of HLA-A,B antigens, and gradual (4 to 6 days) conversion of HEC culture morphology from epithelioid to fibroblastoid, an effect enhanced by immune interferon (IFN-gamma). Induction of H4/18 binding by maximal concentrations of LT or TNF could not be augmented by addition of the other cytokine, and 24 hr pretreatment with LT or TNF produced hyporesponsiveness to both mediators for reinduction. H4/18 binding can be transiently induced by tumor-promoting phorbol esters. Pretreatment with either LT or TNF also fully inhibited induction of H4/18 binding by phorbol ester, whereas phorbol ester pretreatment only variably and partially inhibited reinduction by LT or TNF. These actions of LT on endothelium shared with TNF may serve in vivo to promote lymphocyte and inflammatory leukocyte adhesion and transendothelial migration. Recombinant human interleukin 1 species (IL 1 alpha and IL 1 beta) shared many of the actions of LT and TNF and were indistinguishable from each other. However, IL 1 species could be distinguished from LT/TNF by their relative inability to enhance HLA-A,B expression, by their ability to augment H4/18 binding caused by maximally effective concentrations of LT or TNF, and by their inability to inhibit reinduction of H4/18 binding by LT or TNF. In contrast to the actions of LT or TNF, pretreatment with IL 1 alpha or IL 1 beta only partially inhibited induction of H4/18 binding by phorbol ester, and phorbol ester pretreatment consistently, albeit partially, inhibited induction by IL 1 species. These studies suggest that activated T cells through the secretion of LT can in turn activate the local endothelial lining so as to promote homing and extravasation of inflammatory cells. Furthermore, these LT actions can be augmented or complemented by other locally produced mediators such as IFN-gamma or IL 1.
Monoclonal antibodies distinguish synthetic peptides that differ in one chemical group.
Authors: Motté P , Alberici G , Ait-Abdellah M , Bellet D
Published: December 2022

By using human calcitonin (hCT), human calcitonin-gene-related peptide (hCGRP), and a synthetic peptide with a sequence analogous to the 34 C-terminal amino acids of human preprocalcitonin (designated as PQN-34) as haptens in the generation of monoclonal antibodies, we assessed the role of amido and amino groups in paratope-epitope binding. By using peptide inhibition experiments and solid-phase immunoassays, monoclonal anti-hCT antibody CT07 and monoclonal anti-hCGRP antibody CGR01 were found to bind to an antigenic determinant located in the C-terminal segment of the hormones. These epitopes comprise the seven C-terminal amino acids of the hormones, and the presence of the hormone-ending carboxamide group was found to be essential for antibody binding. The corresponding heptapeptides, either bearing a carboxyl group or else linked to a glycine residue at their C-terminal part, failed to react with the antibodies. Moreover, these monoclonal antibodies did not bind to synthetic peptides analogous to the C-terminal region of the hormone precursor molecules that comprised the epitope site flanked by a peptide sequence. In an attempt to assess whether amido groups when present on the side-chain of amino acids may also modulate antibody binding, a monoclonal antibody referred to as QPO1 was produced and was found to recognize an antigenic determinant localized in the N-terminal region of the PQN-34 peptide bearing a glutamine residue as the N-terminal amino acid. The epitope was found to correspond to a topographic assembled site, and binding of QPO1 was found to be substantially dependent on the presence of the free amino and the side-chain amido groups borne by the N-terminal glutamine residue of this peptide PQN-34. In contrast to these findings, an antigenic determinant located in the internal sequence of calcitonin and recognized by monoclonal anti-hCT antibody CT08 was found to be expressed on the mature form of the hormone, as well as on synthetic peptides with sequence mimicking that of preprocalcitonin. These data should guide the choice of synthetic peptide haptens for the production of anti-protein antibodies.
Identification and characterization of a monoclonal antibody recognizing a galactose-binding domain of the toxin ricin.
Authors: Colombatti M , Johnson V G , Skopicki H A , Fendley B , Lewis M S , Youle R J
Published: December 2022

A monoclonal antibody raised against purified ricin B chain, 75/3B12, blocked ricin toxicity 30- to 100-fold in vitro. The 75/3B12 IgG and F(ab')2 blocked ricin binding to cell surface galactose-containing receptors. The 75/3B12 Fab bound ricin D with a Ka of 10(7) M-1, and this binding was blocked by asialofetuin, lactose, and N-acetylgalactosamine--molecules which interact with the ricin galactose-binding site--but not by fetuin, sucrose, or glucose. The 75/3B12 Fab contained no detectable carbohydrate and, according to several lines of evidence, did not bind ricin via Ig carbohydrate determinants. The monoclonal antibody appears to recognize a galactose-binding site on ricin D via the variable region of the antibody. The 75/3B12 Fab bound ricin E only 1/50 as well as ricin D and bound the Ricinus agglutinin only 1/80 as well as ricin D. The antibody specificity indicates that structural differences exist in the galactose-binding sites of the Ricinus communis lectins. Abrin and other lectins which bind galactose or N-acetylgalactosamine were not significantly bound by the monoclonal antibody. In vitro, the antibody blocked the nontarget toxicity of immunotoxins similarly to lactose. However, in vivo, unlike lactose, the 75/3B12 antibody protected mice from ricin toxicity.
Identification of a rabbit class I-like thymocyte-specific antigen.
Authors: Wang C R , Chen G H , Mandy W J
Published: December 2022

The availability of a monoclonal antibody, 5E2, has made it possible to characterize a new class I-like thymocyte-specific antigen in the rabbit. Flow cytometry and cyto-fluorescent microscopy show that approximately 70 to 80% of the cells reacting with 5E2 are located throughout the thymic cortex. Structural studies reveal that the cell surface molecule recognized by 5E2 is a non-covalently associated heterodimer consisting of a 45,000 dalton glycoprotein and a low m.w. beta-2-microglobulin protein. Certain properties of the 5E2 antigen were similar to the murine TL and human T6 antigens. Therefore we have tentatively assigned to the 5E2 antigen the designation R-Ta on the premise that the structural gene(s) encoding this molecule will be associated with the rabbit major histocompatibility complex.
Circulating parasite antigen(s) in lymphatic filariasis: use of monoclonal antibodies to phosphocholine for immunodiagnosis.
Authors: Lal R B , Paranjape R S , Briles D E , Nutman T B , Ottesen E A
Published: December 2022

Hybridoma cell lines producing monoclonal antibodies (MAb) against a 200 kD antigen found circulating in the sera of microfilaremic patients infected with Wuchereria bancrofti were obtained by immunizing mice with a partially purified antigen preparation. A sensitive MAb (CA101)-based ELISA for measuring circulating parasite antigen was capable of detecting antigen in the sera of 93% of patients with microfilaremia, 46% of those with lymphatic obstruction, and 56% of patients with tropical pulmonary eosinophilia syndrome. Circulating antigen was absent from sera of normal controls, and "false positives" were recorded in only two of 17 patients with nonfilarial helminth infections. By ELISA and immunoblot analysis, it was shown that three of the monoclonals raised to this 200 kD antigen were directed to epitopes of phosphocholine (PC). Two MAb (CA86, CA101) were identified as having the T15 idiotype previously associated with antibodies to the PC of pneumococcal teichoic acid; one was untypeable. All three of these anti-PC MAb reacted with adult, microfilaria, and larval antigen preparations, and by immunoblotting showed multiple banding patterns that indicated the presence of PC determinants on many different antigenic molecules. On the other hand, target antigens of CA101 which were found in the circulation of infected patients were limited to three species with apparent m.w. of 200, 160, and 78 kD. The 200 kD antigen was seen more frequently than the other two antigens. Other T15 anti-PC MAb derived from mice not immunized with filarial antigen showed similar patterns of reactivity with circulating filarial antigen.
Expansion of the complement receptor gene family. Identification in the mouse of two new genes related to the CR1 and CR2 gene family.
Authors: Aegerter-Shaw M , Cole J L , Klickstein L B , Wong W W , Fearon D T , Lalley P A , Weis J H
Published: December 2022

Human cDNA probes encoding the C3b/C4b complement receptor, CR1, have been used to identify, in the mouse, two new genes which are related to CR1 but which appear to encode a different protein product. These new mouse genes, arbitrarily designated mouse genes X and Y, hybridize specifically to three different cDNA probes derived from human CR1. The degree of hybridization homology between the mouse X and Y genes suggests they are very closely related to one another; however, the chromosomal localization of the mouse X gene to chromosome 8 and the mouse Y gene to chromosome 1 indicates they are distinct gene sequences. The mRNA species detected with the X and/or Y (X/Y) sequences are approximately 2000 bases in length, but vary in both quantity and size depending upon the tissue analyzed. DNA sequence analysis of a cDNA specific for the X and Y sequences indicates the mature protein(s) will contain the 60 amino acid consensus repeat characteristic of a group of other proteins including CR1, the C3d receptor (CR2), H, C4 binding protein (C4bp), the interleukin 2 (Il 2) receptor and others. The identity of the mouse X and Y genes, and the function of the proteins which they encode, is not known; however, the small size of the mRNA and the tissue specific expression suggests they do not encode mouse CR1 or CR2 but instead encode a related protein (or proteins) which is expressed in a wide variety of mouse tissues.
Identification and specificity of a cDNA encoding the 70 kd mitochondrial antigen recognized in primary biliary cirrhosis.
Authors: Gershwin M E , Mackay I R , Sturgess A , Coppel R L
Published: December 2022

Mitochondrial autoantibodies are characteristic of the disease primary biliary cirrhosis (PBC), but the immunoreactive mitochondrial antigens have not been defined. We used a rat liver cDNA library in lambda gt 11-Amp3 to clone a 1370-base pair insert that coded for a polypeptide reactive with PBC sera. This insert was subcloned for expression into pBTA224, a plasmid vector in the same reading frame as lambda-Amp3. A positive clone, designated pRMIT, that expressed a fused polypeptide of 160 kd, was recognized by 25 of 25 sera from patients with PBC and none of 96 sera from normal persons or patients with systemic lupus erythematosus, rheumatoid arthritis, or chronic active hepatitis. This fused polypeptide was shown to correspond with the 70 kd mitochondrial autoantigen by several experiments. First, lysates of pRMIT in J101 absorbed out the 70 kd reactivity of PBC sera when probed against fractionated placental mitochondria. Second, affinity-purified antisera reactive with the fused polypeptide also reacted with the 70 kd mitochondrial antigen. Third, such affinity-purified antisera produced the characteristic anti-mitochondrial pattern of immunofluorescence on tissue sections. Finally, immunization of BALB/c mice with the fused polypeptide elicited antibodies to mitochondria. These murine antibodies reacted with the 70 kd mitochondrial protein and also produced typical mitochondrial immunofluorescence on tissue sections. The nucleotide and amino acid sequence of the recombinant protein, which encodes for approximately a 48 kd protein, showed no significant homologies with known proteins, and there were no homologies with mitochondrial genomic DNA. The availability of a recombinant form of the 70 kd mitochondrial autoantigen will allow several definitive questions to be addressed in PBC, including identification of B cell epitopes, T cell recognition, and a model of PBC in mice.