bluuebunny/crossref_metadata_2025 huggingface dataset:
The reactions of monoclonal antibodies with structural proteins of mumps virus.
Authors: Orvell C
Published: December 2022

Mouse hybridomas producing antibodies against structural proteins of mumps virus were established by fusion of FO or SP 2/0 myeloma cells with spleen cells from BALB/c mice immunized with purified preparations of egg-grown mumps virus. Ascites fluids collected after i.p. inoculation of mice were characterized by different serologic tests. By immune precipitation tests with [35S]methionine-labeled mumps virus polypeptides, 17 clones were found to produce antibodies against the nucleocapsid protein (NP), 11 against the polymerase (P) protein, 10 against the membrane (M) protein, 12 against the fusion (F) protein, and 24 against the hemagglutinin-neuraminidase (HN) protein. Competitive binding enzyme-linked immunosorbent assay (ELISA) tests were performed to determine the reactivity of the monoclonal antibodies with different antigenic sites of each structural component. The monoclonal antibodies directed against the NP, P, and M proteins identified a minimum of 10, 10, and 9 separate antigenic sites, respectively. The 12 clones directed against F were directed against a minimum of eight separate antigenic determinants. These antibodies did not neutralize the infectivity of the virus either in the absence or presence of anti-gamma-globulin. Only low capacity to block hemolysis (HL) activity of the virus was detected in clones directed against three of the eight antigenic sites. Based on their serologic reactivity, the 24 clones directed against the HN protein could be divided into four groups. The first group of clones could not inhibit any biologic activity of the protein. The second group consisted of two clones that blocked HL but did not block hemagglutination (HA) or neuraminidase (NA) activity. The third group, which included five clones, blocked HA, NA, and HL activity of the virus and had high neutralizing capacity. These clones were directed against three distinct antigenic sites. Two of the clones directed against one antigenic site could block NA activity only when a large substrate, fetuin, was used, but not when a small substrate, neuraminlactose, was used in the test. The fourth group included five clones that could block NA but not HA activity of the virus. These clones could neutralize the infectivity of the virus and had high capacity to block HL activity. In blocking experiments, all these antibodies reacted with one antigenic site. The reaction of all clones was tested in ELISA with four different strains of mumps virus. Each strain had unique antigenic sites. Variations were found in four, three, and three different antigenic sites of the NP, P, and HN proteins, respectively.
Soluble factors produced during an immune response regulate Ia antigen expression by murine adenocarcinoma and fibrosarcoma cells.
Authors: Callahan G N
Published: December 2022

LT-85 is an alveologenic adenocarcinoma of C3Hf/HeN mice. Comparisons of the in vitro and in vivo surface properties of these cells revealed that under normal conditions, they expressed I-A and I-E antigens iv vivo only. By using clonally derived cells, it was established that this phenomenon was not due to the selection of an Ia antigen-positive tumor cell subpopulation, but resulted from phenotypic conversion of Ia antigen-negative tumor cells. These tumor cells and 1053 cells (a fibrosarcoma of C3H/HeN MTV- mice) could, however, be induced to express I-A, I-E, and much higher levels of H-2 antigens in vitro by co-culturing them with spleen cells from LT-85 tumor-bearing C3H/HeN MTV- mice. In vitro induction of Ia and H-2 antigens did not result from contaminating splenocytes or from antigen transfer, because splenocytes from BALB/c (H-2d) mice immunized with A/J (H-2k/d) cells were able to induce the expression of Iak antigens by both tumor cell lines. It was found that this phenomenon was neither H-2-restricted nor antigen-specific. The results clearly indicated, however, that an immune response was required to generate phenotypic conversion of the tumor cells, both in vivo and in vitro. It was further found that soluble, rather than cellular, factors produced during an immune response induced the expression of Ia antigens by LT-85 and 1053 tumor cells. In contrast to what has been reported about the induction of Ia antigens on macrophages and normal epithelial and endothelial cells, the induction of Ia antigens on LT-85 and 1053 cells did not appear to require T cells, and did not involve gamma-interferon. These findings demonstrate that some tumor cells are capable of altering their MHC antigen phenotype in response to factors produced during an immune response in vivo or in vitro. Because of the involvement of Ia antigens in several aspects of immune phenomena, the ability of tumor cells to differentially express Ia antigens in response to environmental factors may have profound effects on host-tumor interactions. Furthermore, the differences seen in the phenotypes of tumor cells grown in vitro and in vivo suggest that in vitro methodologies of tumor cell characterization may not present a complete picture of the natural state of the tumor cell surface.
Genetic control of the induction of cytolytic T lymphocyte responses to AKR/Gross viral leukemias. I. H-2-encoded dominant gene control.
Authors: Green W R
Published: December 2022

Previously, a system was devised whereby H-2-restricted cytotoxic T lymphocytes could be raised that were specific for tumors induced by endogenous AKR/Gross murine leukemia virus and that displayed the Gross cell surface antigen (GCSA). The generation of such anti-AKR/Gross virus CTL required in vivo priming with allogeneic (H-2 and/or non-H-2 incompatible) GCSA+ tumor cells, followed by in vitro restimulation with H-2-compatible GCSA+ tumor cells. The prototype responder strain of mice was C57BL/6, which is of the H-2b type and which has a low incidence of spontaneous virus-induced leukemia ("low leukemic"). Present experimentation indicates that there is H-2-encoded control of the ability to mount an anti-AKR/Gross virus CTL response. In addition to C57BL/6, all other H-2b strains tested, including C57BL/10, C57L, and 129, were responders. In contrast, H-2k strains of both "high leukemic" (AKR) and "low leukemic" (AKR.Fv-1b and CBA) phenotype appeared to be low- or nonresponders with respect to their ability to generate H-2k-restricted anti-AKR/Gross virus CTL after appropriate stimulation. Furthermore, B6.H-2k congenic mice were also poorly responsive, suggesting that H-2b and H-2k were responder and nonresponder haplotypes, respectively. The finding that (responder X nonresponder)F1, i.e., (B6 X CBA)F1 mice mounted CTL responses to H-2b, but not H-2k, GCSA+ tumors, was consistent with this interpretation and suggested the presence of H-2-encoded dominant immune response genes. The tumors of AKR background that were efficient in the in vivo priming of C57BL/6 mice were relatively inefficient in priming (B6 X CBA)F1 mice for a subsequent in vitro H-2b-restricted anti-AKR/Gross virus CTL response. Because of the similarities in background minor H genes of the AKR and CBA strains, this latter observation was in keeping with the requirement for in vivo stimulation with tumor cell alloantigens in addition to the virus-associated target antigens.
Generalized systemic and mucosal immunity in mice after mucosal stimulation with cholera toxin.
Authors: Elson C O , Ealding W
Published: December 2022

Cholera toxin (CT) has been found to be an extremely potent immunogen for mucosal IgA responses when administered via the intestine. This study has examined both mucosal and systemic immune responses after feeding CT and compared these responses with those obtained after feeding keyhole limpet hemocyanin (KLH), another protein that is strongly immunogenic in mice. Feeding CT to mice resulted not only in IgA antibody in intestinal secretions but also resulted in substantial plasma IgG and IgA antibody levels. Feeding KLH in much larger quantity resulted in little or no antibody response in intestinal secretions or plasma. Lymphoid cells from various tissues of mice fed CT were cultured in vitro for 10 days and the supernatant was tested for antibody to CT. Spontaneous antibody synthesis (no antigen added to cultures) was present in cultures of each cell type, but IgG anti-CT was found mainly in cultures of spleen and mesenteric lymph node cells and IgA anti-CT mainly in cultures of Peyer's patch and lamina propria cells. Peyer's patch cells cultured with CT as antigen synthesized both IgG and IgA anti-CT, suggesting that the antibody response to both isotypes originated in this site. Helper T cell activity for both IgA and IgG anti-CT was detected in spleens, mesenteric lymph nodes, and Peyer's patches. Lastly, when KLH and CT were fed to mice at the same time, an intestinal IgA anti-KLH and plasma IgG anti-KLH response was stimulated, a response pattern similar to that occurring to CT after CT was fed alone. We conclude that mucosal stimulation by CT generates both a systemic IgG and mucosal IgA response to this antigen, and that CT can cause a similar pattern of response to an unrelated protein antigen when both are administered into the intestine at the same time. The data favor the idea that both the IgG and IgA responses originate in GALT and then disseminate to other tissues. We propose that CT accomplishes these effects by altering the regulatory environment within GALT.
Suppression of BCG cell wall-induced delayed-type hypersensitivity by pretreatment with killed BCG: induction of nonspecific suppressor T cells by the adjuvant portion (MDP) and of specific suppressor T cells by the antigen portion (TAP).
Authors: Kato K , Yamamoto K , Kimura T , Azuma I , Askenase P W
Published: December 2022

We showed previously that antigen-nonspecific suppressor T cells induced by i.v. injection of heat-killed bacillus Calmette-Guérin (BCG) were involved in suppression of delayed-type hypersensitivity (DTH). We suggested that the adjuvant portion of BCG might be involved in the induction of these cells. In this report, we show that BCG cell wall-induced DTH responses in mice pretreated with muramyl dipeptide (MDP), a minimum adjuvant constituent of BCG, were suppressed nonspecifically. In addition, we show that pretreatment with tuberculin active peptide (TAP), the antigenic peptide from Mycobacterium tuberculosis, induces antigen-specific suppression of DTH responses. In both instances, suppression was shown to be due to non-adherent cells that act to inhibit elicitation of DTH. Furthermore, using the macrophage migration inhibition assay, an in vitro correlate of DTH, we found that antigen-nonspecific and antigen-specific suppressor T cells were induced by the injection of MDP and TAP, respectively. Thus, suppressor T cells induced by the adjuvant and antigen portions of BCG may act by interfering with the lymphokine-dependent mechanisms by which DTH effector T cells elicit DTH.
Mouse T lymphocytes proliferative responses specific for human MHC products in mouse anti-human xenogeneic MLR.
Authors: Yoshizawa K , Yano A
Published: December 2022

It has been reported that human T cells recognize the polymorphism of murine Ia antigens in the human anti-mouse xenogeneic mixed lymphocyte reactions (MLR). In this study, murine T cell recognition of human Class II antigens of the major histocompatibility complex (MHC) was analyzed in mouse anti-human xenogeneic MLR responses. The xenoreactive murine T cell proliferative response was blocked by adding anti-HLA-DR monoclonal antibody to the xenogeneic MLR culture. The specificity of xenoreactive murine T cells was examined with regard to the secondary and tertiary xenogeneic MLR system. The xenoreactive murine T cells were restimulated by distinct human stimulator cells that had no shared HLA antigens with the stimulator used in the primary MLR. The data presented here show that the murine xenoreactive T cells recognize the shared determinant(s) of HLA-DR antigen on non-T, non-B stimulator cells. The xenoreactive murine T cell proliferative responses were mediated by Thy-1+, Lyt-1+, and Lyt-2- cells. Furthermore, the xenoreactive T cell responses required Ia+ cells, and Ia antigen on accessory cells plays a crucial role in eliciting the xenoreactive responses against human stimulator cells, while Ia+ accessory cells in the responding cell population are not essential for the elicitation of allogeneic MLR responses, as reported previously.
Differential expression of cell activation markers after stimulation of resting human B lymphocytes.
Authors: Kehrl J H , Muraguchi A , Fauci A S
Published: December 2022

The interaction of antigen with surface Ig receptors initiates a complex process by which resting B lymphocytes are activated. In this study, small resting B lymphocytes were isolated by countercurrent elutriation of tonsillar B lymphocytes and stimulated with a range of concentrations of anti-mu and B cell growth factor (BCGF). The subsequent expression of two glycoproteins known to be absent from resting B lymphocytes but present on activated cells were analyzed with the monoclonal antibodies 4F2 and 5E9. The antigen recognized by the 4F2 monoclonal was expressed early in the G1 phase of the cell cycle and correlated with blast transformation; this was demonstrated by stimulating resting B cells with a low concentration of anti-mu sufficient for cellular activation but not proliferation. The 5E9-defined antigen was not present unless the B cells were stimulated with a higher concentration of anti-mu or a BCGF was added to the low concentration of anti-mu. The addition of hydroxyurea to culture blocked the entrance of stimulated B cells into S phase but did not interfere with the expression of either 4F2 or 5E9. Thus, whereas the monoclonal antibody 4F2 recognized cells in early G1, 5E9 recognized cells in late G1. By double immunofluorescence staining with propidium iodide and either 4F2 or 5E9, all cells in S, G2, and M phases were demonstrated to be both 4F2- and 5E9-positive. The monoclonal antibodies 4F2 and 5E9 can be used to distinguish an activated from a resting human B lymphocyte and to delineate sequential steps in the activation process.
Characterization of mouse and human monoclonal antibodies cross-reactive with SLE serum antibodies to guanosine.
Authors: Weisbart R H , Chan G , Kacena A , Saxton R E
Published: December 2022

Two new monoclonal antibodies, one a mouse IgM and the other a human IgM that reacted with guanosine, were compared to human serum antibodies from patients with systemic lupus erythematosus (SLE). The human monoclonal antibody was polyspecific in its binding to the nucleoside bases, whereas the mouse monoclonal antibody was relatively specific for guanosine when compared by using an enzyme-linked immunosorbent assay (ELISA). Neither antibody bound polyguanylic acid or denatured single-stranded (ss) DNA, however. Serum IgG antibodies from seven patients with SLE cross-reacted with the mouse monoclonal antibody and showed considerable specificity for guanosine. In contrast, the human serum IgG antiguanosine antibodies also bound ssDNA but not dsDNA or polyguanylic acid. Serum IgG antibodies to guanosine measured by ELISA from the seven SLE patients had a decreased response when compared to the total serum IgG response to ssDNA, and most of the antibodies that bound guanosine also bound ssDNA. These studies provide new evidence that there are specific IgG antibodies to guanosine in SLE sera that are a small fraction of the antibodies to ssDNA. Further efforts to define the role of these guanosine antibodies in SLE may provide a better understanding of the basic mechanisms responsible for the development of SLE in man.
Secretion of interleukin 2, macrophage-activating factor, interferon, and colony-stimulating factor by alloreactive T lymphocyte clones.
Authors: Kelso A , Glasebrook A L
Published: December 2022

Sixty-four murine alloreactive, cytolytic and noncytolytic , T lymphocyte clones were tested for the production of interleukin 2 (IL 2), macrophage-activating factor (MAF), interferon (IFN), and colony-stimulating factor (CSF). Approximately 90% of both cytolytic and noncytolytic clones secreted MAF and IFN upon antigen or mitogen stimulation. IL 2, in contrast, was only released in detectable amounts by 50% of noncytolytic clones and 50% of a subclass of cytolytic clones in which the proliferation was independent of exogenous IL 2 ("antigen-driven" clones); IL 2-dependent cytolytic clones did not release measurable IL 2. CSF was secreted by approximately 90% of noncytolytic and IL 2-independent cytolytic clones and 40% of IL 2-dependent cytolytic clones. The analysis reported here revealed a strong quantitative correlation between the titers of MAF and IFN released by the clones, suggesting that these two assays may measure the same lymphokine. Although the other activities measured were not directly correlated, a broad association was noted between IL 2 secretion and the production of high titers of MAF, IFN, and CSF. Thus, noncytolytic and IL 2-independent cytolytic clones on average released significantly higher titers of these factors than IL 2-dependent cytolytic clones.
Isolation and characterization of B cell differentiation factor (BCDF) secreted from a human B lymphoblastoid cell line.
Authors: Yoshizaki K , Nakagawa T , Fukunaga K , Tseng L T , Yamamura Y , Kishimoto T
Published: December 2022

A subclone of a human B lymphoblastoid cell line, CESS-2, spontaneously secreted a kind of BCDF (B-BCDF) in their culture supernatant without any stimulation. B-BCDF induced IgG and IgM secretions in human B lymphoblastoid cell lines, CESS cells and CL-4 cells, respectively. BCDF-responsive CESS cells expressed IgG on their surface, whereas CESS-2, which were able to secrete B-BCDF, did not express surface IgG. B-BCDF could induce Ig-secretion in SAC-stimulated low density peripheral B cells, but did not induce Ig secretion in nonstimulated B cells. B-BCDF did not show any IL 2, BCGF, or gamma-interferon activities. B-BCDF was highly purified by gel filtration on an AcA-34 column, by chromatofocusing and ion exchange chromatography on an HPLC system, and by gel filtration on an HPLC column. Highly purified preparations showed a single protein band in SDS-PAGE analysis. The m.w. and isoelectric points of the factor were 20,000 and pH 5.1 to 5.2, respectively. The minimum protein amount required for Ig induction in B cell lines was 16 ng/ml.
Changes in conformation with loss of alloantigenic determinants of a histocompatibility antigen (HLA-B7) induced by monoclonal antibodies.
Authors: Parham P
Published: December 2022

Two conformations of HLA-B7 have been characterized. In one conformation B7 has epitopes that are: specific to B7, shared with B27, shared with B40, and common to many HLA-B locus products. In the second conformation the B7-specific and B7/B27 cross-reactive epitopes are effectively lost and an additional epitope that is shared with B40 has been acquired. The conformation of papain-solubilized and cell surface B7 can be reversibly changed by monoclonal antibodies against the appropriate epitopes. Antibody bivalency is not an important factor in these changes. In the second conformation B7 is antigenically indistinguishable from B40. It is suggested that conformational changes of this magnitude could contribute to the adaptability of histocompatibility antigens in forming functional complexes with many pairs of T cell receptors and foreign antigens.
Characterization of human interleukin 2 receptor (Tac antigen) in normal and leukemic T cells: co-expression of normal and aberrant receptors on Hut-102 cells.
Authors: Wano Y , Uchiyama T , Fukui K , Maeda M , Uchino H , Yodoi J
Published: December 2022

Human interleukin 2 receptors ( IL2R ) from various cell sources such as mitogen-activated normal human T cells, adult T cell leukemia (ATL)-derived cell line cells (MT-1, ATL-6, Hut-102), and a natural killer-like cell line YT cells, were studied both by one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), with a monoclonal anti- IL2R antibody (anti-Tac). In synthetic labeling with [35S]methionine, anti-Tac specifically precipitated two glycoproteins, one with m.w. of 60,000 to 65,000 and pI 4.2 to 4.7, and the other with m.w. about 40,000 and pI 6.2 to 6.5. A study of surface iodination revealed that the former component was membrane-associated mature IL2R , and a pulse-chase study showed that the latter component was a precursor for IL2R that already possessed tunicamycin-sensitive N-linked sugar side chain(s). This precursor was found to be posttranslationally processed into mature IL2R by further glycosylation within 240 min. Among the cells studied, a human T cell leukemia virus-positive leukemic cell line, Hut-102, was distinctive in that it possessed an additional membrane glycoprotein (m.w. 55,000 to 60,000, pI 4.2 to 5.0) also defined by anti-Tac. This unique glycoprotein of Hut-102 cells appeared to be an aberrant IL2R .
In situ identification of cells in human leprosy granulomas with monoclonal antibodies to interleukin 2 and its receptor.
Authors: Modlin R L , Hofman F M , Horwitz D A , Husmann L A , Gillis S , Taylor C R , Rea T H
Published: December 2022

Leprosy is a chronic granulomatous disease with an immunologic spectrum in which lepromatous leprosy patients have defective cell-mediated immune responses, in comparison to tuberculoid leprosy patients. Immunoregulatory aspects of this spectrum were investigated by using monoclonal antibodies to interleukin 2 (IL 2), IL 2 receptors (Tac), and T lymphocyte subpopulations with immunoperoxidase techniques on frozen sections of skin biopsy specimens from 10 tuberculoid and 10 lepromatous patients. A comparison of IL 2+ cells revealed markedly fewer IL 2+ cells in lepromatous specimens (lep. 0.028% +/- 0.02 vs tub. 0.46% +/- 0.28, p less than 0.001). These IL 2+ cells were large, exhibited cytoplasmic staining, and on double immunostaining were Leu-4+, Leu-3a+, Leu-2a-, Tac-, and OKT6-, consistent with the fact they are IL 2 producers. Equivalent numbers of Tac+ cells were observed in both lepromatous and tuberculoid granulomas (lep. 1.5% +/- 0.5 vs tub. 2.1% +/- 0.7, p, NS), suggesting that the responder cells are present in both conditions. The tuberculoid granuloma was highly organized, composed of a central core of mature macrophages, Leu-3a+ and Tac+ cells with a surrounding mantle of Leu-2a+, Leu-3a+, IL 2+, Tac+, and OKT6+ cells. In lepromatous granulomas, Leu-2a+, Leu-3a+, Tac+, and rare IL 2+ cells were randomly admixed with bacilli-laden macrophages. The defective cell-mediated immune responses in lepromatous leprosy appears to be associated with diminished IL 2 production and disorganization of the granuloma.
Analysis of mRNA coding for blood-stage antigens of a rodent malarial parasite, Plasmodium yoelii: mRNA coding for a possible protective antigen purify as poly A-.
Authors: Vaidya A B , Schleif W A , Majarian W R , Daly T M , Taylor D W , Long C A
Published: December 2022

We have analyzed mRNA coding for blood-stage antigens of Plasmodium yoelii by using cellfree translation of poly A+ and poly A- RNA in conjunction with immunoprecipitations. Most of the antigens recognized by mouse hyperimmune serum to P. yoelii were coded by poly A+ mRNA ranging in size from 15S to 28S. However, certain P. yoelii antigens, notably those with m.w. greater than 150 kilodaltons (kd), were coded by mRNA that purified as being poly A-. Antigens recognized by a protective monoclonal antibody (McAb) were coded by such operationally poly A- RNA. Three polypeptides apparently coded by different poly A- RNA were immunoprecipitated by this McAb. With the use of another McAb, a poly A+ mRNA of about 19S was identified as coding for a polypeptide of 46 kd synthesized in cellfree translation reactions. The same McAb recognized a 34 kd polypeptide in metabolically labeled polypeptides of P. yoelii. This antigen appeared to be processed in vivo but not in vitro. The observation that some mRNA of P. yoelii purify as being poly A- has significant implications for the construction of cDNA libraries that employ poly A+ mRNA of malarial parasites: if it applies to other species of plasmodia, some potentially important operationally poly A- mRNA may not be represented in such libraries.
Purification of a glycoprotein bearing a tumor transplantation antigen specific for Friend, Moloney, and Rauscher MuLV-induced tumors.
Authors: Rogers M J , Galetto G , Hearing V J , Siwarski D F , Law L W
Published: December 2022

A 175,000 dalton glycoprotein bearing a tumor-associated transplantation antigen (TATA) has been isolated from a Rauscher-MuLV-induced leukemia (RBL-5). The glycoprotein has the properties expected for a Friend, Moloney, or Rauscher-MuLV-induced TATA: 1) It is synthesized by RBL-5 cells and is expressed on the cell surface. 2) When inoculated into mice, it provides complete protection against challenge with RBL-5 cells at doses of 1 microgram or less. 3) The same protein, isolated from a Moloney-MuLV-induced leukemia, also protects mice against challenge with RBL-5. A similar glycoprotein is expressed on other tumor cells and on normal cells that do not express a TATA cross-reactive with RBL-5. Therefore, the immunogenicity of this molecule cannot be principally accounted for by either its unique or elevated expression on RBL-5 cells. A model is presented that accounts for these properties of the RBL-5 TATA. In addition, two other features of the RBL-5 TATA are discussed; an apparent abrogation of immunity seen only with certain doses of antigen, and a loss of the inherent immunogenicity of gp175 during purification.
The role of T3 surface molecules in the activation of human T cells: a two-stimulus requirement for IL 2 production reflects events occurring at a pre-translational level.
Authors: Weiss A , Wiskocil R L , Stobo J D
Published: December 2022

The human T cell leukemia Jurkat was used as a model to examine the requirements of T cell activation. These studies demonstrated that antibodies reactive with the T cell-specific T3 antigen were insufficient to result in the activation of Jurkat cells, determined by the secretion of IL 2. IL 2 production occurred only in the presence of a second stimulus, the phorbol ester PMA. With the use of an IL 2-specific cDNA probe, the appearance of IL 2 RNA, similarly, occurred only when cells were stimulated with both anti-T3 antibodies and PMA. These results demonstrate a two-stimulus requirement for gene expression in human T cells.
Recognition of H-2Kb mutant target cells by Moloney virus-specific cytotoxic T lymphocytes from bm13 (H-2Db mutant) mice. I. Full recognition of Kbm11 by Kb-restricted CTL.
Authors: Stukart M J , Boes J , Melief C J
Published: December 2022

In C57BL/6 (B6, H-2b) mice, the secondary in vitro CTL response against Moloney leukemia virus is restricted and regulated by the H-2Db locus. B6.C-H- 2bm13 ( bm13 ) mice, however, carrying a mutation at the Db locus, show an increased H-2Kb-restricted CTL response without a demonstrable CTL component restricted by the mutant Dbm13 molecule (D----K shift). These purely Kb-restricted bm13 virus-specific CTL were incubated with a series of Kb mutant virus-infected target cells to study the effect of the mutations at the target cell level. Of six Kb-mutant virus-infected target cells tested, bm1 cells were not recognized and bm8 cells were recognized only marginally by bm13 virus-specific CTL, whereas bm3 , bm5 , bm6 , and bm11 cells were fully recognized. Thus, the bm3 , bm5 , bm6 , and bm11 Kb mutants fully share the relevant H-2K restriction specificities with H-2Kb, whereas the bm1 mutant totally and the bm8 mutant almost completely lack these specificities. This result differs markedly from the restriction site relationships among B6 and these Kb mutants in other antigenic systems. The most striking example concerns the bm11 mutant, which is fully recognized by Moloney-specific CTL, but not at all by Sendai, minor H (H-3.1, H-4.2), and sulfhydryl hapten-specific CTL. Monoclonal anti-H-2Kb antibody B8-3-24 inhibited virus-specific lysis by bm13 CTL of all Kb virus-infected mutant target cells to which this antibody binds. Lysis of bm5 and bm11 but not of bm3 target cells was inhibited, in line with the fact that B8-3-24 antibody does not bind bm3 . On the other hand, not only bm5 and bm11 but also bm3 virus-infected target cells blocked virus-specific lysis to the same extent as syngeneic bm13 target cells. Therefore, bm13 virus-specific CTL populations do not recognize the discrete cluster alteration in the Kbm3 molecule, as identified by antibody B8-3-24. The bm1 and the bm8 mutations, which have structural alterations in completely different sites of the Kb molecule, show complete or almost complete loss, respectively, of Kb-Moloney restriction sites. This finding supports the notion that these virus-specific CTL recognize conformational determinants rather than linear amino acid sequences.
Induction of autoantibodies to thyroglobulin by anti-idiotypic antibodies.
Authors: Zanetti M , Rogers J , Katz D H
Published: December 2022

We report on the induction of autoantibodies to thyroglobulin (Tg) and idiotype-positive molecules (Id') in naive BALB/c mice and Buffalo (BUF) rats after immunization with affinity-purified rabbit anti-Id antibodies directed against the Id of a mouse monoclonal antibody ( mAb62 ) specific for a hormone-containing epitope of Tg. Autoantibodies to Tg were produced in about one-half of anti-Id immunized mice, whereas Id' was detected in all but one mouse. Autoantibodies to Tg and Id' were not produced in control mice similarly immunized with non-anti-Id Ig. To clarify the relationship between molecules with Tg-binding activity and those referred to as Id', Tg-specific monoclonal antibodies were generated from an anti-Id-immunized mouse. By competitive inhibition experiments, we could determine that they were idiotypically very similar to the monoclonal antibody ( mAb62 ) at the origin of the immunologic cascade. Thus, autoantibodies induced by anti-idiotypic immunization alone are likely to be of the Ab1' type. Similarly, autoantibody to Tg and Id' molecules were induced in young normal rats of the autoimmune-prone BUF strain. Together, these results suggest that antibodies to Id directed against autoantigens are sufficient per se to activate self-reactivity.
Interleukin 3 augments the murine primary cytolytic T lymphocyte response to allogeneic tumor cells.
Authors: Curtsinger J M , Fan D P
Published: December 2022

The primary anti-H-2k allospecific cytolytic T lymphocyte (CTL) response by BALB/c (H-2d) spleen cells in vitro to x-irradiated RDM4 (H-2k) tumor cells is weak. This response has been shown to be augmented by CTL helper factor (CHF), a factor present in supernatants of spleen cells cultured with Sendai virus (SC-CM). Conditioned medium from WEHI-3 cells (WEHI-CM) also contains activity that augments the BALB/c anti- RDM4 CTL response. Attempts to separate the CHF activity from interleukin 3 (IL 3), also present in WEHI-CM, were unsuccessful. Purified IL 3 was then tested, and was found to increase the BALB/c anti- RDM4 CTL response by five- to 10-fold. IL 3 is apparently the only material in WEHI-CM that is active in this assay. The response is apparently a classical CTL response because: 1) the effector cells are sensitive to monoclonal anti-Thy-1.2 antibody plus C; 2) the response is dependent on antigen stimulation, and it peaks on day 5 or 6 of culture; and 3) the effector cells are specific for H-2k targets. IL 3 must be added very early during the in vitro culture period for maximal augmentation of the response, consistent with possible action of IL 3 as a differentiation factor.
Differences in lymphocyte responsiveness to lymphokines in two inbred strains of Syrian hamster.
Authors: Wright K E , Clark D A , Rawls W E
Published: December 2022

Two inbred strains of Syrian hamster have been shown to display differences in splenic NK cell activity both endogenously and after infection with Pichinde virus. On further investigation of these differences, it was found that the spleens and thymuses of the high NK strain, MHA, displayed greater cellularity than those of the low NK strain, LSH. Additionally, thymocytes from MHA hamsters were found to proliferate to a greater extent than those of LSH hamsters in response to Con A-induced conditioned medium plus lectin. Splenocytes from MHA hamsters showed high levels of lymphokine-activated killer cell (LAK) activity after culture in conditioned medium, in contrast to LSH splenocytes cultured under the same conditions. By limiting dilution analysis, spleens from MHA hamsters were found to contain a greater frequency of LAK precursors than those from LSH hamsters. The data suggest that the relative concentrations of lymphopoietic cells is genetically determined.
Lactoferrin acts on I-A and I-E/C antigen+ subpopulations of mouse peritoneal macrophages in the absence of T lymphocytes and other cell types to inhibit production of granulocyte-macrophage colony stimulatory factors in vitro.
Authors: Broxmeyer H E , Platzer E
Published: December 2022

The relationship between Ia antigens on mouse resident peritoneal macrophages and the ability of lactoferrin (LF) to inhibit the production of granulocyte-macrophage colony stimulatory factors (GM-CSF) from these cells was investigated. Detection of the suppressive influence of LF on release of GM-CSF from greater than or equal to 10(5) macrophages/ml/plate required that the conditioned media being assessed for GM-CSF be prepared in the presence of indomethacin and/or be preincubated with anti-ferritin antiserum to respectively stop production of E-type prostaglandins and to remove acidic isoferritin-inhibitory activities that can mask the effects of LF. Treatment of mouse macrophages with monoclonal antibodies to the I-A and I-E/C subregions of Ia antigens in a complement C-dependent cytotoxicity assay killed less than 15% of the cells, but removed all Ia antigen+ macrophages and reduced GM-CSF production by approximately 50%. LF decreased GM-CSF production by untreated macrophages by approximately 50%, but had no effect on macrophages insensitive to treatment with anti-Ia plus C. Macrophages left at 37 degrees C for 5 and 24 hr were not killed by treatment with monoclonal anti-Ia plus C and GM-CSF production by these macrophages was not suppressed by LF. Treatment of macrophages with monoclonal anti-H-2K or anti-Mac-1 plus C reduced GM-CSF production greater than 95%. Anti-I-A, -I-E/C, -H-2K, or -Mac-1, in the absence of C, had no effect on viability of macrophages or on production of GM-CSF, but anti-I-A and -I-E/C each blocked the inhibitory action of LF. Lower concentrations of these antibodies could block the action of LF when anti-I-A and anti-I-E/C were mixed together better than when they were each used separately. The removal of Thy-1.2+ cells from unseparated or adherent peritoneal cells resulted in populations of cells that were up to 100% positive for nonspecific esterase, and did not influence GM-CSF production from these cells, the reduction of GM-CSF from these cells by LF, or the reduction of GM-CSF by the removal of Ia antigen+ cells. The results were similar whether or not T cells were removed from the assay marrow by treatment with antibodies Ly-1.1, Ly-2.2, and Qa4 plus C.(ABSTRACT TRUNCATED AT 400 WORDS)
Target cell susceptibility to immune lysis and expression of MHC antigens are independent of position in the cell cycle.
Authors: Harris D T , Sekaly R P
Published: December 2022

We have investigated the effects of progression through the mitotic cell cycle upon the tumor (P815) cell line's expression of H-2 antigens and susceptibility to immune cytolysis. By using a combination of DNA quantitation by Hoechst 33342 staining and fluorescence-activated cell sorter analysis we were able to obtain pure populations of G1, S, and G2+M cells for study. Furthermore, by employing a fluorescence quenching technique utilizing bromodeoxyuridine substitution we were able to monitor the times required for the P815 cells to transit each of the various phases. By using mAb and cloned CTL populations with well-defined specificities we observed that neither H-2 antigen expression nor lytic susceptibility to mAb plus complement or CTL fluctuated with cell cycle progression. Each of the three major MHC loci (H-2Kd, -Dd, and -Ld) was analyzed. These results demonstrated that expression of H-2 antigens and susceptibility to immune lysis were independent of a cell's position in the cell cycle.
Strategies for production of monoclonal anti-idiotype antibodies against human B cell lymphomas.
Authors: Thielemans K , Maloney D G , Meeker T , Fujimoto J , Doss C , Warnke R A , Bindl J , Gralow J , Miller R A , Levy R
Published: December 2022

Murine monoclonal antibodies (MAB) against the idiotype (Id) of B lymphocyte malignancies are powerful reagents for the study of these diseases, and are potentially useful for treatment. Different strategies for the production of these anti-Id MAB have been compared. Initially, the Id Ig from nonsecreting B cell tumors was "rescued" by human X mouse or human X human hybridization. These somatic cell hybridizations resulted in the secretion of human Ig in 10 and 100% of the fusions, respectively. In a second step, anti-Id MAB were produced by using the "rescued" Id Ig as immunogen. A more streamlined approach is based on a one-step procedure in which the tumor cell suspension is used as immunogen. This method of immunization, coupled with a four-layer ELISA, results in the detection of anti-Id MAB in a frequency of approximately 1% of the total hybrids. By using a pool of 10 different anti-Id MAB, each reactive with the tumor of one patient, we searched for idiotypic relatedness among a panel of 50 additional tumors. No cross-reactions were found, indicating that our current strategy results in the identification of unique idiotypic determinants among human B cell tumors. Idiotypic Ig can be found in the serum of patients with B cell tumors. Among groups of patients, there is a wide spectrum of serum Id levels, ranging from less than 0.01 microgram/ml to greater than 500 micrograms/ml.
Successful immunotherapy with intraperitoneal Corynebacterium parvum in a murine ovarian cancer model is associated with the recruitment of tumor-lytic neutrophils into the peritoneal cavity.
Authors: Lichtenstein A K , Kahle J , Berek J , Zighelboim J
Published: December 2022

The rejection of a murine ovarian teratocarcinoma (MOT) after i.p. injection of Corynebacterium parvum was investigated. Treatment with C. parvum (1400 micrograms) 24 hr after i.p. inoculation of a lethal number of tumor cells (10(5] induced an antitumor effect that cured 75 to 95% of the mice. Morphologic analysis and an in vivo cytotoxicity assay that measured the rate of disappearance of radioactivity from the peritoneal cavity after injection of 125IUdR-labeled tumor cells indicated that the antitumor effect was initiated during the first 24 hr after C. parvum injection. During this period of time, host effector cells retrieved from the peritoneal cavity prevented tumor growth in a Winn assay and lysed radiolabeled MOT targets in a 4-hr Cr-release assay. After separation of peritoneal inflammatory cells on a Percoll gradient, neutrophil-enriched fractions demonstrated significant in vitro tumor lysis, but neutrophil-depleted populations were ineffective. Microscopic analysis of lysis at the single cell level confirmed that neutrophils were binding to and lysing MOT targets. Further characterization of these tumor cytolytic neutrophils revealed that they are nylon wool-adherent, not generated in indomethacin-pretreated mice (but effectively generated in whole body-irradiated mice), and achieve lysis within 30 min after binding to MOT targets. These results indicate that neutrophils must be considered potential antitumor effectors that can be recruited by treatment with biologic response modifiers.
Rescue of the tumor-specific immune response of aged mice in vitro.
Authors: Urban J L , Schreiber H
Published: December 2022

In contrast to young mice, old mice fail to reject a transplanted challenge of the highly immunogenic, ultraviolet light-induced tumor 1591-RE. Old mice also fail to mount a cytolytic tumor-specific immune response in vivo, and spleen cells of old mice are defective in their ability to generate tumor-specific T cells in vitro. In the present study we report the results of cell culture mixing experiments that show that this deficiency is due to a decreased responsiveness of the Lyt-2+ tumor-specific cytolytic T cell precursors of the old animals. We also demonstrate with limiting dilution analysis that the defective responsiveness is not due to a clonal exhaustion of the precursors. In fact, the responsiveness could be restored in vitro by culturing the spleen cells of old animals at high density or by the addition of excess Lyt-1-/Lyt-2-/2000-rad-resistant spleen cells from young or old mice. Our results suggest that the rescue of tumor immunity in old individuals may be possible, perhaps by educating effector cells in vitro for adoptive immunotherapy.
Role of accessory cell processing and presentation of shed H-2 alloantigens in allospecific cytotoxic T lymphocyte responses.
Authors: Golding H , Singer A
Published: December 2022

The present study was undertaken to evaluate the role of accessory cell processing of MHC alloantigens in the initiation of primary allospecific CTL responses. To first determine whether antigen processing by accessory cells is involved in the initiation of allospecific CTL responses, accessory cells were retreated with the lysosomotropic drug chloroquine before their addition to culture. It was found that chloroquine pretreatment abrogated their ability to function as accessory cells only when they were of responder haplotype and had no effect when the accessory cells were of stimulator haplotype. Although accessory cells of either responder or stimulator haplotype can initiate allospecific CTL responses, we have previously demonstrated that they do so by activating distinct classes of T helper TH) cells. Indeed, the differential effects of chloroquine on accessory cells of responder or stimulator haplotypes were shown to reflect the fact that chloroquine pretreatment markedly impaired the ability of accessory cells to activate self-Ia-restricted TH cells, but had little effect on the ability of the same accessory cells to activate either allo-class I- or allo-class II-specific TH cells. We next examined the possibility that accessory cells of responder haplotype mediate alloresponses by acquiring and processing shed MHC alloantigens derived from the stimulator cell population. In these experiments, accessory cell-depleted stimulator cells were fixed with paraformaldehyde to inhibit shedding of their surface MHC alloantigens. It was observed that even though mixed stimulator cells were recognized normally by allospecific CTL precursors, they completely failed to stimulate CTL responses mediated by responder haplotype accessory cells, indicating that the function of such accessory cells is dependent upon their acquisition of shed MHC alloantigens. Taken together, the data presented in this report demonstrate that accessory cells of responder haplotype function in allospecific CTL responses by acquiring and processing shed class I MHC alloantigens, and by then presenting the processed alloantigens in association with self-Ia determinants to self-Ia-restricted TH cells. Thus, these data indicate that the self-Ia-restricted TH cells that are involved in allospecific CTL responses recognize processed class I alloantigens in association with self-Ia determinants.
Regulation of the activation of cytotoxic T lymphocytes by prostaglandins and antigens.
Authors: Ting C C , Hargrove M E
Published: December 2022

The present study demonstrated the presence of two suppressor circuits in the regulation of the in vitro activation and differentiation of cytotoxic T lymphocytes (CTL); these suppressor circuits were mediated by prostaglandins (PG) and antigens, respectively. In intrinsic suppression, the activation of cytotoxic precursor cells was regulated by the host endogenous production of PG. When the regulation by PG was removed (e.g., using indomethacin), lymphokine-induced cytotoxic cells (LICC) were generated. This activation process can be induced in the absence of antigen or mitogen stimulation. In extrinsic suppression, the presence of antigen induced the generation of antigen-nonspecific suppressor T cells to restrict the expansion of antigen-unrelated cytotoxic lymphocyte clones, whereas the antigen-specific CTL clones were spared. The generation of antigen-specific helper cells further augmented the antigen-specific CTL response. These findings indicate that both antigen specific suppressor T cells and antigen nonspecific suppressor T cells are involved in the regulation of CTL responses. These suppressor circuits not only play an active role in monitoring the activation of CTL clones, they also help to determine the specificity and magnitude of the CTL response.
Expression of C3d receptors during human B cell differentiation: immunofluorescence analysis with the HB-5 monoclonal antibody.
Authors: Tedder T F , Clement L T , Cooper M D
Published: December 2022

We have examined human B lymphocytes at different stages of differentiation for the expression of surface receptors for the C3d fragment of complement. C3d receptors (C3dR) were identified by indirect immunofluorescence using the HB-5 monoclonal antibody, which recognizes a 145,000 m.w. C3dR molecule on B lymphocytes. Pre-B and immature B cells from fetal bone marrow and liver did not express C3dR, whereas a small subpopulation (25%) of B cells in fetal spleen were C3dR+. Approximately 50% of the B cells in adult bone marrow were C3dR+, whereas the more mature B cells in the blood of newborns and adults and in peripheral lymphoid tissue of adults uniformly expressed the C3dR. Activated B cells responsive to T cell-derived differentiation factors were C3dR+, whereas plasma cells rarely expressed C3dR. T cells, NK cells, erythrocytes, and myelomonocytic cells did not express detectable surface C3dR. These results suggest that in hematopoietic and lymphoid tissues, the expression of C3dR is a specific feature of relatively mature lymphoid cells of B lineage.
Immune function in severe, active rheumatoid arthritis: a relationship between peripheral blood mononuclear cell proliferation to soluble antigens and mononuclear cell subset profiles.
Authors: Haraoui B , Wilder R L , Malone D G , Allen J B , Katona I M , Wahl S M
Published: December 2022

We have previously reported that patients with active rheumatoid arthritis and depressed in vitro peripheral blood mononuclear cell proliferation to soluble recall antigens (anergic subgroup) improve clinically after repeated short-term leukapheresis, whereas patients with normal responses (nonanergic subgroup) do not. This observation prompted us to examine the mononuclear cell subset profiles in the peripheral blood of anergic and nonanergic seropositive rheumatoid arthritis patients with severe, active, clinically similar disease not taking long-acting anti-rheumatic drugs. In the present study, 42 patients were categorized as anergic (n = 14) or nonanergic (n = 28) on the basis of in vitro peripheral blood mononuclear cell proliferation to soluble recall antigens. The anergic patients had a decreased frequency of OKT4+ mononuclear cells (p less than 0.01), and an increased frequency of OKT8+ cells (p less than 0.02), with a lower OKT4+ :OKT8+ ratio (p less than 0.01) than the nonanergic patients. Anergic patients also had a higher frequency of HLA-DR+ mononuclear cells and HLA-DR+ T cells (p less than 0.001). About 50% of the OKT8+ cells were HLA-DR+, whereas only about 20% of the OKT4+ population expressed HLA-DR antigens. These data suggest that the decreased lymphocyte function described in the anergic patient subgroup is associated with characteristic peripheral blood mononuclear cell subset profiles. Moreover, when considered in the context of other data indicating that anergic patients have characteristic synovial immunopathologic abnormalities, these data provide insight into potential pathogenic mechanisms of this disorder.