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J M Chiller

Publications and source records attributed to J M Chiller.

At least 19 recordsLinked to original sources
PubMed1991

Identification of a novel protein capable of interacting with the IL-3 receptor.

IL-3 has numerous functions in hematopoiesis yet its receptor has not been fully characterized. We have developed two mAb, 4G8 and 2F2, that markedly inhibited IL-3-dependent proliferation whereas only marginally affecting IL-2 or IL-4-induced proliferation. On Western blots, both antibodies identified the same protein, which varied in size from 115 to 145 kDa in six cell lines tested. The 4G8/2F2 Ag was detected at moderate density, on a wide variety of cells including IL-3-dependent cell lines and T lymphocytes. Radioligand binding studies revealed that 4G8, but not 2F2, could inhibit the binding of 125I-IL-3 to the high affinity IL-3R. These data suggest that the mAb 4G8 and 2F2 recognize different epitopes on the same Ag, and suggest furthermore that the inhibition of IL-3-dependent proliferation mediated by 2F2, in particular, does not occur via inhibition of ligand binding. Neither antibody showed an enhanced level of fluorescent staining of Cos 7 cells transfected with the low affinity IL-3R cDNA. In addition, 4G8 did not inhibit IL-3 binding to L cells transfected with the cloned IL-3R or IL-4R despite the fact that 4G8 was expressed on these cells. These data suggest that the 4G8/2F2 Ag is a unique cell surface protein that can interact with the endogenous functional IL-3R.

Animals↗
PubMed1990

Dissociation of antigenicity and immunogenicity of neonatal epidermal allografts in the mouse.

Cultured neonatal epidermal cells or sheets have been grafted successfully onto allogeneic recipients across an MHC barrier, while genetically identical skin allografts were rejected. Induction of specific allosensitization by prior priming with allogeneic spleen cells or allogeneic skin grafts did not prejudice the survival of subsequent cultured epidermal allografts. When cultured epidermis and adult skin of the same genotype were grafted simultaneously, as double grafts, cultured epidermis survived despite the presence of an ongoing allograft rejection reaction in the host. Furthermore, pretreatment of the recipients with cultured epidermis failed to protect against rejection of subsequent allogeneic adult skin grafts of the same genetic origin. These data indicate that cultured epidermis is neither immunogenic nor antigenic in allogeneic host. In companion experiments it was determined that neonatal (noncultured) epidermal allografts also survived indefinitely, implying that neonatal epidermis lacks antigenicity. However, in contrast to cultured epidermis, neonatal epidermal allografts evoked specific systemic immunity in their recipients, since they rejected a subsequent allogeneic adult skin grafts in accelerated fashion. These data demonstrate that in neonatal epidermis antigenicity can be dissociated from immunogenicity.

Animals↗
PubMed1989

Enumeration of cytokine-secreting cells at the single-cell level.

A sensitive assay utilizing enzyme-linked immunosorbent assay methodology has been developed for the quantitation of single cells secreting interferon (IFN)-gamma or tumor necrosis factor (TNF). Cloned T cells or cells from lymphoid organs were stimulated with antigen, concanavalin A, or phorbol myristate acetate and ionomycin in microwells coated with antibodies specific for IFN-gamma. Discrete "spots" overlying areas where cells secrete IFN-gamma were then developed by incubation with a second antibody to IFN-gamma, followed by an enzyme-labeled antibody conjugate and substrate. Similarly, using TNF-specific antibody reagents, TNF-secreting cells were detected and quantitated in cell populations obtained from normal lymphoid tissues, bone marrow and peripheral blood, following activation with phorbol myristate acetate and ionomycin. Provided specific antibodies are available, this method has the potential to measure the frequency of cells secreting any cytokine.

Animals↗
PubMed1986

Interferon-gamma-induced IA expression in WEHI-3 cells is enhanced by the presence of 1,25-dihydroxyvitamin D3.

It has been suggested recently that 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] is involved in the regulation of the immune functions of lymphocytes and in the differentiation of monocytic cells. This report examined the possibility that 1,25(OH)2D3 influences immune functions mediated by monocytic cells by studying its effect on the murine myelomonocytic line WEHI-3. We found that WEHI-3 cells possess 3.3S receptor proteins with high affinity (Kd = 3.3 X 10(-10) M) for 1,25(OH)2D3 that are capable of binding to DNA. Also we found that 1,25(OH)2D3 enhances the interferon-gamma (IFN-gamma)-induced expression of the class II major histocompatibility complex antigens (Ia molecules), and such enhancement leads to increased capacity of the WEHI-3 cells to stimulate antigen-specific Ia-restricted T cell activation. Finally, 1,25(OH)2D3 inhibits the proliferation of WEHI-3 cells, and this inhibition is enhanced in the presence of IFN-gamma. The 1,25(OH)2D3 modulation of IFN-gamma induction of Ia antigens suggests that the hormone might promote monocytes to function more efficiently as antigen-presenting cells.

Animals↗
PubMed1986

Murine T cells reactive to type II collagen. I. Isolation of lines and clones and characterization of their antigen-induced proliferative responses.

Mice of the DBA/1 strain develop arthritis after immunization with native chick type II collagen. Although both a humoral and a cell-mediated response specific to type II collagen are associated with the disease, the underlying immunologic basis remains to be established. As an initial step to analyzing the involvement of cellular immunity in collagen-induced arthritis, we isolated and characterized T cell lines and clones specific to type II collagen. Two sets of T cell lines were obtained by limiting dilution. One set was found to react exclusively with denatured type II collagen, whereas the other set responded to both native and denatured type II collagen. The specificity of such T cells was demonstrated by their inability to respond to other soluble proteins such as type I collagen, HGG, KLH, or OVA. Cells from these lines recognized type II collagen only in an MHC (H-2q)-restricted fashion. Furthermore, the collagen-specific T cells were found to respond to type II collagens obtained from various species, including chick, bovine, and rat. Finally, each set of cells displayed a phenotype characteristic of T helper cells, namely Thy-1+, L3T4+, Lyt-2-.

Animals↗
PubMed1986

Murine T cells reactive to type II collagen. II. Functional characterization.

DBA/1 mice immunized with native chick type II collagen (NcII) emulsified in complete Freund's adjuvant develop arthritis, whose underlying mechanisms are still undefined. As an initial step to studying the role of T cells in collagen-induced arthritis (CIA), we have established T cell lines specific to type II collagen. Characterizations of the antigen-induced proliferative responses mediated by these T cells have been reported. In essence, two major populations of collagen-reactive T cells were isolated: those that responded mainly to denatured type II collagen (DcII) and another group that reacted with both DcII and NcII. As shown in the present study, all of the collagen-reactive T cell lines isolated were found to be functional, although they differed in their capacity to mediate helper activities assessed by different assays. Hence, both populations of T cells exhibited the ability to trigger B cell proliferation, whereas only the population that recognized both DcII and NcII was capable of activating the synthesis of immunoglobulins by B cells. T cells from this latter group also provided specific help for the generation of a secondary anti-DNP antibody response. In addition, these T cells were capable of activating NcII-specific B cells to produce anti-collagen antibodies. By contrast, the T cell lines that reacted exclusively to DcII failed to mediate such specific helper functions. The inability of such T cells to activate DNP-primed B cells upon challenge with DNP-DcII did not appear to be due to a modification of antigenic sites on DcII by haptenation. Inasmuch as the DcII-specific T cell lines also proliferate less well in response to DcII than the T cell lines that recognize both DcII and NcII, a difference in the nature of the antigen receptors expressed by the two populations of collagen-specific T cells may partly explain the above observations. However, the inability to generate appropriate factors required for further differentiation of B cells to produce antibodies may also account for the failure of DcII-specific T cells to activate DNP-primed B cells. Finally, both populations of T cells were capable of mediating specific delayed-type hypersensitivity response.

Animals↗
PubMed1986

Recognition of exon-shuffled class II molecules by T helper cells.

Exon shuffled I-A beta genes transfected into the B lymphoma cell line A20-2J were used to localize the epitope recognized by the monoclonal antibody 10.2.16 to the carboxy terminal portion of the beta 1 domain. In addition, several T helper cell hybrids were tested against these novel I-A molecules and the following observations were made: the beta 1 domain of A beta plays a dominant role in the restricted recognition by T helper cells; there appear to be multiple restriction epitopes on the I-A molecule; these epitopes can consist of conformational epitopes created by specific alpha and beta chains or consist of the polymorphic determinants encoded on the beta chain alone, and these novel I-A molecules serve as restriction elements in the antigen-specific recognition by T cells and in one case stimulate an alloreaction in the absence of antigen.

Amino Acid Sequence↗
PubMed1986

Effect of myeloma IgE injections on passive and active cutaneous anaphylaxis in rats.

The ability of injected rat IgE myeloma protein IR162 to inhibit passive and active cutaneous anaphylaxis in Lewis rats was investigated. IgE injected i.p. 24 hr before the sensitization with IgE anti-ovalbumin (OVA) completely inhibited both IgE- and IgG2a-induced passive cutaneous anaphylactic (PCA) reactions at a dose (2.5 mg/100 g body weight) that resulted in peak serum concentrations of 150 micrograms IgE IR162/ml. Peak IgE IR162 serum concentrations of 20 to 60 micrograms/ml inhibited the PCA reaction in approximately 50% of the rats. Intracutaneous injection of a mixture of myeloma IgE and anti-OVA IgE in a ratio of 100:1 or more also inhibited the PCA reaction. In contrast, the PCA reaction was not inhibited by seven daily doses of IgE beginning 24 hr after passive sensitization. Likewise, the cutaneous anaphylactic reaction elicited in rats 14 days after immunization with OVA and Bordetella pertussis was not prevented by daily injections of myeloma IgE despite a 1000- to 3000-fold excess of the myeloma IgE to anti-OVA IgE serum concentration. The data demonstrate that parenteral administration of myeloma IgE inhibits the PCA reaction only when given before passive sensitization and does not prevent cutaneous anaphylaxis in actively immunized rats. Because myeloma IgE failed to inhibit anaphylactic reactions in actively immunized rats, it is questionable whether administering human IgE-derived synthetic peptides or recombinant DNA-produced IgE fragments will be able to prevent allergic diseases by blocking the IgE Fc receptors on mast cells.

Anaphylaxis↗
PubMed1985

Leukotriene C4 production by murine mast cells: evidence of a role for extracellular leukotriene A4.

The glutathione-containing leukotriene C4 (LTC4) is a major mediator of smooth muscle contraction and is released by mast cells when antigen interacts with cell-bound IgE. Antigen-stimulated mast cells undergo phospholipase activation. We report a pathway of LTC4 production by mast cells that does not require phospholipase activation but depends on the interaction of activated neutrophils with unstimulated mast cells, using as an intermediate extracellular leukotriene A4 (LTA4). The epoxide LTA4 is released by neutrophils and, together with leukotriene B4 and 5-hydroxyeicosatetraenoic acid, constitutes the major lipoxygenase metabolites found in supernatants of stimulated neutrophils. Five minutes after activation of neutrophils by calcium ionophore A23187 we measured 136 pmol of extracellular LTA4 per 10(7) neutrophils (range 40-300, n = 7) by trapping the epoxide with alcohols. Therefore, we conclude that LTA4 is not just an intracellular leukotriene precursor but is released as a lipoxygenase metabolite. LTA4 is known to be stabilized by albumin and is efficiently converted by mast cells into LTC4 even at low LTA4 concentrations. The LTA4 complexed to albumin is converted into LTC4 rapidly and completely within 10-15 min. More than 50% of the LTA4 presented to mast cells is metabolized to LTC4 at concentrations of LTA4 between 0.2 and 2 nmol of LTA4 per 10(7) mast cells. This observation establishes a potential physiologic role for extracellular LTA4. Therefore, interactions between various cell types that release or utilize LTA4 may provide an important metabolic pathway for the production of leukotrienes.

Animals↗
PubMed1985

In vivo maturation of pre-B cells derived from long-term cultured bone marrow.

Long-term culture of a nonadherent pre-B cell line was established from BALB/c bone marrow by the method of Whitlock and Witte. Adherent filler cells, also derived from bone marrow, were required for the growth of such pre-B cells. The surface phenotypes of the nonadherent cells determined by FACS analysis were negative for mu-chain, kappa-chain, and Ia, but 50% of nonadherent cells expressed a marker recognized by the monoclonal 14.8. Analysis of cytoplasmic immunofluorescent staining revealed the presence of cytoplasmic mu-chain but absence of kappa-chain. These pre-B cells did not respond in vitro to such mitogens as LPS or DxSO4 and were not stimulated by allospecific helper T cells. However, when such BALB/c derived pre-B cells were transferred to irradiated BDF1 mice, recovered spleen cells expressed mu-chain as well as the marker recognized by 14.8. Such in vivo passaged pre-B cells were able to respond to LPS in vitro. Moreover, the response observed was diminished markedly by anti-H-2d antiserum and complement (C) but not anti-H-2b and C, indicating that the responder cells were of donor rather than host origin. Because the reconstitution of irradiated mice was limited to cells of the B lymphocyte lineage, it would appear that cells recovered from in vivo passage are the progeny of in vitro cultured pre-B cells and not that of in vitro contaminating stem cells.

Animals↗
PubMed1985

Lymphokine-mediated induction of cytolytic activity in a T cell hybridoma.

Functionally inducible CTL hybridomas were constructed by fusing alloantigen-specific T cells (C57BL/6 alpha-DBA/2) with cells from the rat thymoma line W/FU (C58NT)D. A cloned hybridoma line (KSH.4.13.6) that was specifically cytolytic in the presence of activated rat spleen cell supernatant fluid (rat Con A SN) lost activity when transferred to normal medium. However, a cytolytic activity could be reinduced by culturing KSH.4.13.6 cells in medium containing rat Con A SN or secondary mixed leukocyte culture SN. By using various sources of SN, it was found that cytolytic induction required two different factors. PMA-induced EL-4 SN and SN from antigen-activated cloned T cells, neither of which were capable of inducing cytolytic activity alone, were able to synergize in the cytolytic induction of KSH.4.13.6 IFN-gamma and IL 1 failed to induce cytolytic activity even in the presence of EL-4 SN. Furthermore, this hybridoma produced macrophage activating factor (MAF) upon culture in rat Con A SN, although MAF production could not be induced by either specific antigen or lectins. The kinetics of induction and loss of cytolytic activity mediated by rat Con A SN were similar to those of the induction of MAF production. However, EL-4 SN, which by itself was incapable of inducing cytolytic activity, was able to induce MAF production in the KSH.4.13.6 hybrid to an extent similar to that induced by rat Con A SN. These results suggest that the induction of cytolytic activity and of MAF production in this cloned hybridoma cell line are regulated by different mechanisms. Such a functionally inducible T cell hybrid may provide a tool for biochemical and molecular analysis of T cell function and regulation, and of the characterization of cytokines required for CTL differentiation.

Animals↗
PubMed1984

Selection of genetic variants of lymphocytic choriomeningitis virus in spleens of persistently infected mice. Role in suppression of cytotoxic T lymphocyte response and viral persistence.

We studied the mechanism of lymphocytic choriomeningitis virus (LCMV) persistence and the suppression of cytotoxic T lymphocyte (CTL) responses in BALB/c WEHI mice infected at birth with LCMV Armstrong strain. Using adoptive transfer experiments we found that spleen cells from persistently infected (carrier) mice actively suppressed the expected LCMV-specific CTL response of spleen cells from normal adult mice. The suppression was specific for the CTL response and LCMV -specific antibody responses were not affected. Associated with the specific CTL suppression was the establishment of persistent LCMV infection. The transfer of spleen or lymph node cells containing LCMV -specific CTL resulted in virus clearance and prevented establishment of the carrier state. The suppression of LCMV -specific CTL responses by carrier spleen cells is not mediated by a suppressor cell, but is due to the presence of genetic variants of LCMV in spleens of carrier mice. Such virus variants selectively suppress LCMV-specific CTL responses and cause persistent infections in immunocompetent mice. In striking contrast, wild-type LCMV Armstrong, from which these variants were generated, induces a potent CTL response in immunocompetent mice and the LCMV infection is rapidly cleared. Our results show that LCMV variants that emerge during infection in vivo play a crucial role in the suppression of virus-specific CTL responses and in the maintenance of virus persistence.

Acute Disease↗
PubMed1983

The capacity of murine alveolar macrophages to stimulate antigen-dependent T-lymphocyte activation and proliferation.

To define the antigen-presenting capacity of alveolar macrophages (AM phi), their ability to activate antigen-specific T cells was determined. It was found that AM phi s are at least as potent as spleen cells at presenting alloantigen or soluble protein antigen plus I-region determinant to cloned T-cell hybridomas. Activation of those hybridomas, shown by interleukin 2 (IL-2) secretion, further indicated the presence on AM phi s of functional products of the I-A and I-E subregions. In addition, it was found that AM phi s are at least as potent as spleen cells and peritoneal macrophages at inducing, in a restricted fashion, specific proliferation of primed, propagated lymph node T cells. AM phi s are thus potent accessory cells in vitro, whose in vivo significance in this capacity remains to be defined.

Animals↗
PubMed1983

Induction of tolerance in influenza virus-immune T lymphocyte clones with synthetic peptides of influenza hemagglutinin.

Antigen-specific human T cell clones specific for defined peptides of influenza A hemagglutinin were found to be rendered unresponsive by incubation with moderately high concentrations of antigen. This was the case whether the synthetic peptide antigen was present for the duration of the culture or the cloned T cells were preincubated with antigen for 3-18 h at 37 degrees C, before stimulation with T-depleted irradiated sheep erythrocyte non-rosette-forming lymphocytes (E-) pulsed with the optimal dose of peptide. Tolerance could not be overcome by culture with various numbers of E- cells and antigen. The induction of unresponsiveness was antigen specific, since it depended upon incubation with the appropriate peptide recognized by that clone. In addition, the tolerant T cells remained unresponsive to stimulation with the specific peptide for at least 7 d after induction even though maintained in culture in the presence of T cell growth factor. This state of antigen-specific unresponsiveness is akin to immunological tolerance. Furthermore, the experiments reported here demonstrate that the helper T cell clone can be inhibited by the relevant peptide in the absence of any suppressor cells or their precursors. This suggests that antigen-induced unresponsiveness need not always depend on the presence of suppressor T cells. The induction of tolerance in T cell clones does not result in early T cell death, since cells that no longer proliferate in response to the specific antigen and accessory cells still proliferate in response to T cell growth factor.

Antibodies, Viral↗
PubMed1983

Unresponsiveness in hapten-specific cytotoxic lymphocytes. III. Influence of H-2 and non-H-2 gene loci on the in vitro trinitrophenyl-specific CTL response following either acute or chronic in vivo treatment with trinitrobenzene sulfonic acid.

The regulation of the in vitro generation of cytotoxic T lymphocytes (CTLs) directed against hapten-modified syngeneic cells has been investigated. The results indicate that acute intravenous pretreatment with water-soluble hapten, trinitrobenzene sulfonic acid (TNBS), can either positively or negatively affect the in vitro generation of trinitrophenyl (TNP)-specific CTLs. In general, mice bearing the H-2d haplotype are most likely to develop a reduced in vitro response pattern following a single acute in vivo TNBS treatment, wheras mice bearing the H-2k or H-2b haplotypes display either unchanged or augmented in vitro response patterns. We have shown that, in addition to the influences of H-2 genes, non-H-2 genes can also influence the in vitro hapten-specific CTL response following intravenous pretreatment with water-soluble hapten. Further, in two (H-2k X H-2d) F1 combinations between an H-2k strain displaying an unchanged in vitro response pattern following acute in vivo TNBS treatment and an H-2d strain displaying a reduced in vitro response pattern following similar treatment, it was observed that a single in vivo TNBS pretreatment did not induce the unresponsive state when F1-TNP stimulator cells were used. These results suggest that the mechanisms responsible for the reduced in vitro response pattern are not dominant within the F1 environment. However, when TNP-modified parental stimulators are used, a split-response pattern is observed in cells from TNBS-treated F1 mice which reflect the response patterns of the respective parents. These latter results again emphasize the influence of gene loci on the in vitro response patterns following acute TNBS treatment. In contrast to the significant influence of H-2 and non-H-2 genes on the in vitro TNP-specific response following acute in vivo TNBS treatment, these genes do not appear to significantly influence the in vitro TNP-specific response pattern following chronic TNBS treatment. Chronic TNBS treatment renders all strains tested specifically unresponsive.

Animals↗
PubMed1983

Maturation of the lymphoid system. IV. Ontogenetic compartmentalization of T cell function.

Pretreatment of one day old but not eight day old or adult A/J mice with soluble ovalbumin (OVA) initiated specific T-cell unresponsiveness as reflected both in T-cell dependent cellular proliferation and in anti-hapten antibody responses to dinitrophenyl-OVA. In contrast, injection of soluble human gamma globulin into either neonatal or adult A/J mice resulted in unresponsiveness. The ability of lymph node T-cells to be sensitized by protein antigens occurred shortly after birth, since the degree of sensitization in 9 and 26 day old mice was similar. Finally, a striking ontogenetic difference was noted in the capacity of lymphocytes derived from the lymph nodes and spleens of young mice to respond to T-cell mitogens. Thus, while splenocytes obtained from 9 day old mice exhibited meager responses to PHA and Con A, lymph node cells from these animals responded at nearly adult levels. These observations are interpreted as reflecting an ontogenetic and tissue-specific division of T-cell function.

Age Factors↗
PubMed1983

Maturation of the lymphoid system. III. Induction of selective unresponsiveness by injection of a haptenated carbohydrate into neonatal mice.

Neonatal treatment of A/J mice with DNP-Ficoll reduced or eliminated indirect anti-DNP PFC normally produced in response to adult challenge with DNP-keyhole limpet hemocyanin. The remaining direct anti-DNP PFC response was of low avidity. Spleen cells from neonatal A/J mice inhibited the in vitro but not the in vivo response of adult spleen cells to DNP-Ficoll.

Animals↗