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E A Lerner

Publications and source records attributed to E A Lerner.

49 records · Page 3Linked to original sources
PubMed1982

Immune response gene function correlates with the expression of an Ia antigen. I. Preferential association of certain Ae and E alpha chains results in a quantitative deficiency in expression of an Ae:E alpha complex.

These studies were stimulated by the observation, reported in the accompanying paper (19), that IEu failed to interact with I-Ak or I-As in F1 mice to allow a response to the antigen, pigeon cytochrome c, unlike I-E subregions derived from other Ia.7+ haplotypes. Serological and biochemical analyses were performed to determine whether or not cells from these F1 mice express the Ak,se:E alpha complexes that should function as restriction elements for T cell recognition of pigeon cytochrome c on antigen-presenting cells. Using the Y-17 monoclonal antibody, which recognizes the combinatorial or conformational determinant Ia.m44 on certain Ae:E alpha complexes, we were able to distinguish between Aue:Eu alpha and Ab,k,se:Eu alpha complexes on cell surfaces. Although complement-dependent microcytotoxicity with Y-17 failed to detect Ab,k,se:Eu alpha complexes on cells from appropriate F1 mice, these molecules were detected by both quantitative absorption and quantitative immunofluorescence studies. However, Ab,k,se:Eu alpha complexes were found to be present at levels only one-seventh to one-eighth the levels expressed by homozygous I-Ab, I-Ek; I-Ak, I-Ek; and I-As, I-Ek cells. The results of two-dimensional polyacrylamide gel electrophoresis analyses suggest that the low levels of expression of Ab,k,se:Eu alpha complexes are a consequence of the preferential association of Aue and Eu alpha chains with each other in the F1 cells. As will be shown in the following paper (19), the quantitative deficiency in the expression of Ake:Eu alpha and Ase:Eu alpha complexes results in a corresponding defect in antigen-presenting cell function, thus providing strong evidence that Ia antigens represent products of Ir genes.

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PubMed1982

Immune response gene function correlates with the expression of an Ia antigen. II. A quantitative deficiency in Ae:E alpha complex expression causes a corresponding defect in antigen-presenting cell function.

A series of experiments were performed to explore the role of complementing major histocompatability complex (MHC)-linked immune response Ir genes in the murine T cell proliferative response to the globular protein antigen pigeon cytochrome c. The functional equivalence of I-E-subregion-encoded, structurally homologous E(a) chains from different haplotypes bearing the serologic specificity Ia.7 was demonstrated by the complementation for high responsiveness to pigeon cytochrome c of F(1) hybrids between low responder B 10.A(4R) (I-A (k)) or B 10.S (I-A(8)) mice and four low responder E(a)- bearing haplotypes. Moreover, this Ir gene function correlated directly with both the ability of antigen-pulsed spleen cells from these same F(1) strains to stimulate pigeon cytochrome c-primed T cells from B10.A or B10.S(9R) mice, and with the cell surface expression of the two-chain Ia antigenic complex, A(e):E(a), bearing the conformational or combinatorial determinant recognized by the monoclonal anti-Ia antibody, Y-17. The B 10.PL strain (H-2(u)), which expresses an Ia.7-positive I-E- subregion-encoded E(a) chain, failed to complement with B10.A(4R) or B10.S mice in the response to pigeon cytochrome c. However, (B10.A(4R) x B10.PL)F(1) and (B10.S x B10.PL)F(1) mice do express A(k)(e):E(u)(a) and A(8)(e):E(u)(a) on their cell surface, although in reduced amounts relative to A(k,s)(e):E(k,d,p,r)(a) complexes found in corresponding F(1) strains. This quantitative difference in Ia antigen expression correlated with a difference in the ability to present pigeon cytochrome c to B 10.A and B 10.S(9R) long-term T cell lines. Thus, (B10.A(4R) x B10.PL)F(1) spleen cells required a 10-fold higher antigen dose to induce the same stimulation as (B10.A(4R) x B10.D2)F(1) spleen cells. In addition, the monoclonal antibody, Y-17, which reacts with A(e):E(a) molecules of several strains, had a greater inhibitory effect on the proliferative response to pigeon cytochrome c of B10.A T cells in the presence of (B10.A(4R) X B10.PL)F(1) spleen cells than in the presence of (B10.A(4R) X B10.D2)F(1) spleen cells. These functional data, in concert with the biochemical and serological data in the accompanying report, are consistent with the molecular model for Ir gene complementation in which appropriate two-chain Ia molecules function at the antigen-presenting cell (APC) surface as restriction elements. Moreover, they clearly demonstrate that the magnitude of the T cell proliferative response is a function of both the concentration of nominal antigen and of the amount of Ia antigen expressed on the APC. Finally, the direct correlation of a quantitative deficiency in cell surface expression of an Ia antigen with a corresponding relative defect in antigen-presenting function provides strong independent evidence that the I-region-encoded Ia antigens are the products of the MHC-linked Ir genes.

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PubMed1982

Idiotypic analysis of a monoclonal anti-Sm antibody.

Among murine models of autoimmunity, MRL mice are unique in their expression of antibodies to the nuclear antigen Sm. To assess genetic mechanisms in the control of this response, the idiotypes borne by a monoclonal anti-Sm antibody of MRL-Ipr/Ipr origin were investigated. Rabbit antisera were prepared against Y2, a hybridoma product with anti-Sm activity, and were rendered specific for idiotype by extensive absorption with normal globulins from BALB/c mice. In assays of idiotype by an inhibition ELISA, Y2 was shown to share idiotypes with Y12, another monoclonal anti-Sm derived from the same fusion as Y2; other monoclonal autoantibodies of MRL origin but different antigenic specificity failed to display idiotype activity in this assay. The presence of other anti-idiotypic specificities was revealed by absorption and elution of the anti-idiotype from an MRL globulin column; sera from both anti-Sm-positive and negative mice demonstrated these idiotypes. These results suggest that the predominant specificities detected by the anti-idiotype were unique to the monoclonal antibodies of the same animal, although there was also activity to idiotypes not related to anti-Sm binding molecules.

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PubMed1982

Differential expression of Ia glycoprotein complexes in F1 hybrid mice detected with alloreactive cloned T cell lines.

T cell lines alloreactive to Aeb:E alpha Ia antigen complexes have been prepared and used to determine the relative amount of Aeb:E alpha expressed by stimulator cells in homozygous recombinant and F1 mice expressing these complexes. We find that homozygous cells stimulate most strongly and therefore probably express the highest density of Aeb:E alpha. Among heterozygotes, H-2bxd F1 mice preferentially express Aeb:E alpha d complexes, H-2bxa F1 mice express relatively fewer Aeb:E alpha k complexes, and H-2bxu F1 mice express preferentially Aeu:E alpha u complexes. This differential association of Aeb chains with E alpha chains thus influences the biologic activity of these Ia antigens in this and other functional assays. The functional data are supported by biochemical analysis of Aeb:E alpha complex expression. These findings suggest that a reanalysis of HLA-DR associations with human diseases should be undertaken in which both HLA-DR alleles are included, with the prediction that certain combinations would show greater susceptibility, whereas others would show less susceptibility than predicted from the susceptibility associated with presence of a single allele at HLA-DR.

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PubMed1981

Inhibition of T cell activation in vivo with mixtures of monoclonal antibodies specific for I-A and I-A/E molecules.

(CBA x B6)F1 (Iak x Iab) T cells were activated to sheep erythrocytes in irradiated F1 mice in the presence of various monoclonal anti-Ia reagents and then tested for their capacity to collaborate with B cells from B10.BR (I-Ak, I-Ek) (kk), B10.A(4R) (kb), and B10 (bb) mice. Anti-I-Ak antibodies blocked the generation of help for B10.A(4R) B cells, but not B10.BR or B10 B cells. An anti-I-Ab antibody blocked help for B10 B cells, but not for B10.BR or B10.A(4R) B cells. An antibody (Y-17) specific for I-Ak/Ek and I-Ab/Ek molecules, but not for I-Ak or I-Ab molecules, failed to impair the generation of help for B10.BR, B10.A (4R), or B10 B cells. In marked contrast to injecting each antibody separately, a mixture of anti-I-Ak and anti-I-Ak,b/Ek (Y-17) antibodies virtually abolished the generation of help for B10.BR B cells. A mixture of anti-I-Ak and anti-I-Ab antibodies effectively blocked help for (4R x B10)F1 B cells, i.e., cells expressing hybrid I-A molecules. These two antibodies only marginally impaired help for (CBA x B6)F1 B cells. To block help for (CBA x B6)F1 B cells required selection in the presence of a cocktail of anti-I-Ak, anti-I-Ab, and anti-I-Ak,b/Ek antibodies. The implications of these findings are discussed.

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PubMed1981

Antigen-specific T cell clones restricted to unique F1 major histocompatibility complex determinants. Inhibition of proliferation with monoclonal anti-Ia antibody.

The existence of T cells specific for soluble antigens in association with unique F(1) or recombinant major histocompatibility complex (MHC) gene products was first postulated from studies on the proliferative response of whole T cell populations to the antigen poly(Glu(55)Lys(36)Phe(9))(n) (GLphi). In this paper we use the newly developed technology of T lymphocyte cloning to establish unequivocally the existence of such cells specific for GLphi and to generalize their existence by showing that F(1)- specific cells can be isolated from T cell populations primed to poly(Glu(60)Ala(30)Tyr(10))(n) (GAT) where such clones represent only a minor subpopulation of cells. Gl.4b-primed B10.A(5R) and GAT-primed (B10.A x B10)F(1) lymph node T cells were cloned in soft agar, and the colonies that developed were picked and expanded in liquid culture. The GLphi-specific T cells were then recloned under conditions of high-plating efficiency to ensure that the final colonies originated from single cells. T cells from such rigorously cloned populations responded to stimulation with GILphi but only in the presence of nonimmune, irradiated spleen cells bearing (B10.A x B10)F(1) or the syngeneic B 10.A(5R) recombinant MHC haplotype. Spleen cells from either the B10 or B 10.A parental strains failed to support a proliferative response, even when added together. (B10 x B10.D2)F(1) and (B10 x B10.RIII)F(1) spleen cells also supported a proliferative response but (B10 x B10.Q)F(1) and (B10 X B10.S)F(1) spleen cells did not. These results suggested that the T cell clones were specific for GL[phi} in association with the beta(AE)(b)-alpha(E) (k,d,r,) Ia molecule and that recognition required both gene products to be expressed in the same antigen-presenting cells. Support for this interpretation was obtained from inhibition experiments using the monoclonal antibody Y-17 specific for a determinant on the beta(AE)(b)-alphaE Ia molecule. Y-17 completely inhibited the proliferative response of a GLphi-specific clone but had no effect on the response of either a PPD-specific or GAT-specific clone, both of which required the beta(A)-alpha(A) Ia molecule as their restriction element. No evidence could be found for the involvement of suppressor T cells in this inhibition. We therefore conclude that the phenomenon of F(1)-restricted recognition by proliferating T cells results from the presence of antigen- specific clones that must recognize unique F(1) or recombinant Ia molecules on the surface of antigen-presenting cells in addition to antigen in order to be stimulated.

Animals↗
PubMed1981

Monoclonal antibodies to nucleic acid-containing cellular constituents: probes for molecular biology and autoimmune disease.

Mice of the strain MRL/Mp-lpr/lpr develop a lupus erythematosus-like syndrome that includes the production of autoantibodies specific for nucleic acid-containing cellular components. We have fused spleen cells from such a mouse with the myeloma SP 2/0 and examined the antibodies produced by the resultant cloned hybrid cell lines by using immunoprecipitation and immunofluorescence techniques. Three types of monoclonal antibodies, specific for Sm, DNA, or rRNA, all antigens to which patients who have lupus make antibodies, have been identified. Patient anti-Sm antibody had previously been reported to precipitate five small nuclear ribonucleoproteins that contain U-1, U-2, U-4, U-5, and U-6 RNAs. The monoclonal anti-Sm antibody gives the same immunoprecipitation pattern, providing direct evidence that the Sm antigen resides on all these RNA-protein complexes. Monoclonal anti-Sm antibody will be valuable in deciphering the biological function of these ubiquitous small nuclear RNPs. A simple competition radioimmunoassay using the monoclonal anti-Sm antibody to titer patient sera is also presented. Uses of monoclonal antibodies for the study of autoimmune disease are discussed.

Animals↗
PubMed1980

Monoclonal antibody against an Ir gene product?

Genetic, biochemical, and functional studies have been performed using a monoclonal antibody, Y-17, directed at a conformational or combinatorial determinant formed by certain Ae:E alpha complexes. This determinant appears to be a marker present on a subset of B cells as well as on non-T and non-B spleen cells. Besides Ae and E alpha chains, Y-17 precipitates a third chain that is indistinguishable from the A alpha chain in two-dimensional gels. This results suggests additional combinatorial complexity in the generation of I-region encoded antigens. Y-17 can inhibit the response of T cells to Ae:E alpha determinants in mixed lymphocyte cultures. Furthermore, Y-17 blocks antigen-specific T cell proliferative responses to GLPhe and pigeon cytochrome c which have been shown to require the Ae:E alpha complex as a restriction element for antigen presentation. These results provide strong evidence for the molecular identity of Ia antigens, Ir-gene products and Lad antigens.

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PubMedDate not supplied

How to make a hybridoma.

The use of monoclonal antibodies produced by the hybridoma technique has had a profound impact on the biological and medical sciences. While the general technique for the production of monoclonal antibodies is available from the numerous papers which report their use, there is a need for a source which describes the procedure and its pitfalls in detail so that an investigator who decides to make hybridomas can do so quickly and easily. This guide provides such a source.

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