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Biomedical subjects

L Steinman

Publications and source records attributed to L Steinman.

At least 217 records · Page 12Linked to original sources
PubMed1988

Characterization of a major encephalitogenic T cell epitope in SJL/J mice with synthetic oligopeptides of myelin basic protein.

The C-terminal 89-169 amino acid fragment of myelin basic protein (MBP) causes experimental allergic encephalomyelitis (EAE) in SJL/J mice. In order to identify the encephalitogenic T cell epitope, we have examined the fine specificity of encephalitogenic SJL/J T cell clones with synthetic peptides derived from the C-terminal 89-169 amino acids of MBP. These peptides were examined for their immunogenic and encephalitogenic activity in the SJL/J mouse. The SJL/J-derived, encephalitogenic T cell clone, 4b.14a, was shown to be responsive to rat myelin basic protein synthetic peptides pR89-101 (VHFFKNIVTPRTP) as well as to intact MBP. Its response was effectively blocked by mAb 10-2.16 (anti-I-As) as was the response to intact MBP. Furthermore, pR89-101 was revealed to be highly immunogenic for the (PLSJ)F1 mouse in terms of lymphocyte proliferation, but not for the PL/J mouse, in spite of the fact that there exists a strong bias to H-2u restricted responses in the (PLSJ)F1 mouse at the T cell level. By using pR89-101, T cells of (PLSJ)F1 origin were revealed to recognize the peptide in association with the I-As molecule on (PLSJ)F1 antigen presenting cells (APC). When examined for encephalitogenicity for the SJL/J mouse, pR89-101 was found to be as encephalitogenic as intact rat MBP. These results demonstrated that MBP peptide pR89-101 is a major encephalitogenic determinant for the SJL/J mouse.

Amino Acid Sequence↗
PubMed1988

Polymorphic markers of human T-cell receptor alpha and beta genes. Family studies and comparison of frequencies in healthy individuals and patients with multiple sclerosis and myasthenia gravis.

Polymorphic markers for the human T-cell receptor (TcR) genes are described. With a TcR beta-chain probe, polymorphic allelic fragments of 5.4 and 1.8 kb were detected in KpnI digests, and fragments of 12.5 and 11.5 kb were seen in the BglII digests. Polymorphism in alpha chain genes was observed in TaqI-digested DNA samples with bands at 10.2 and 6.2-2.1 kb. Mendelian codominant inheritance for all three polymorphisms was confirmed in family studies. The gene frequencies for these alleles were determined in a sample of 70 normal unrelated Caucasian individuals, and were shown to be in Hardy-Weinberg equilibrium. There were no significant differences in the frequency of these polymorphic alpha and beta alleles between patients with multiple sclerosis and patients with myasthenia gravis as compared to a panel of control healthy individuals.

Alleles↗
PubMed1988

Narcolepsy-cataplexy in Israeli Jews is associated exclusively with the HLA DR2 haplotype. A study at the serological and genomic level.

Narcolepsy is a very rare disease among Israeli Jews with a frequency of 7/3 X 10(6). An investigation of the association of narcolepsy with the human leukocyte antigen system was conducted in Israeli Jews at the serologic and genomic levels. The human leukocyte antigen class I and class II antigen typing of 7 clinically diagnosed narcoleptics, 3 individuals suffering from sleep disorders other than narcolepsy, and 11 healthy matched controls revealed that all narcoleptic patients (100%) investigated in the present study carried the HLA-DR2 haplotype, whereas patients with other sleep disorders did not. The HLA-B7 and DR2 occurred jointly in 57% (4/7) of the narcoleptic patients, as compared to 2% in randomly selected Israeli healthy controls. Restriction fragment length polymorphism analysis was performed with several restriction enzymes and three cDNA probes for DQ alpha, DQ beta, and DR beta genes on genomic DNAs obtained from narcoleptics and patients with other sleep disorders, matched controls, and 3 homozygous typing cells representing the DR2 subtypes Dw2, Dw12, and DwAZH. The restriction fragment length polymorphism analysis showed that all narcoleptics (7 of 7) shared virtually identical restriction fragment length polymorphisms with one of the homozygous typing cells (GSO), which defines DR2,Dw2. The frequency of the DR2,Dw2 haplotype in the healthy Israeli population is 3.2%. Other non-narcoleptic patients did not share these restriction fragment length polymorphisms. These findings indicate that narcolepsy is associated worldwide with the HLA-DR2,Dw2 haplotype.

Adult↗
PubMed1988

Successful treatment of EAE in rhesus monkeys with MHC class II specific monoclonal antibodies.

Experimental Allergic Encephalomyelitis (EAE) was induced in rhesus monkeys by subcutaneous immunization with calfbrain homogenate in complete Freunds adjuvant. Monkeys were treated with major histocompatibility complex (MHC) Class II specific monoclonal antibodies (MoAb) as soon as the first clinical EAE signs became apparent. Two different treatments were tested. One consisted of 10 daily injections of a mixture of two MHC Class II specific MoAb, reactive with a monomorphic structure of rhesus monkey Class II molecules. The other consisted of 10 daily injections of Genox3.53, specific for HLA-DQW1. This MoAb crossreacts well with monkeys and also detects a polymorphism in this species and is presumably reactive with the RhLA-DQW1 antigen. Both MoAb treatments could modify the clinical course of EAE favourably. Untreated animals invariably died within 3 d of the onset of clinical EAE signs. Only one of the three monkeys treated with the monomorphic MHC Class II MoAb preparation died within 3 d, and the other two survived significantly longer than untreated animals. Both animals treated with Genox3.53 survived significantly longer than untreated control animals. Although only a few animals were tested, these results clearly show the possible beneficial influence of MHC Class II specific MoAb on a T-cell mediated autoimmune disease.

Animals↗
PubMed1988

HLA class II allelic variation and susceptibility to pemphigus vulgaris.

The autoimmune dermatologic disease pemphigus vulgaris (PV) is associated with the HLA serotypes DR4 and DRw6. Susceptibility to PV could be conferred either by sequences shared between the DR4 and DRw6 haplotypes or by different sequences in these haplotypes. We have examined the distribution of DR and DQ beta-chain and DQ alpha-chain alleles in PV patients and in control subjects by hybridization with oligonucleotide probes and sequence analysis of in vitro amplified DNA. Ninety percent (34/38) of the DR4 haplotypes in patients contain a specific DR beta I sequence present in 36% (16 of 44) of DR4 controls (P = 0.001). This sequence is also found in DRw6 haplotypes. However, it is present in only 25% (6 of 24) of DRw6 patients. The results of our analysis indicate that predisposition to PV is conferred by different sequences in DR4 and DRw6 haplotypes. The DR4 susceptibility is highly associated with the Dw10 DR beta I allele, implicating the polymorphic residues in the third hypervariable region. The DRw6 susceptibility is strongly associated with a rare DQ beta allele (DQB1.3). This allele differs from a common DQ beta allele (DQB1.1) only by a valine----aspartic acid substitution at position 57.

Alleles↗
PubMed1988

Involvement of distinct murine T-cell receptors in the autoimmune encephalitogenic response to nested epitopes of myelin basic protein.

The peptide p89-101 (Val-His-Phe-Phe-Lys-Asn-Ile-Val-Thr-Pro-Arg-Thr-Pro) of myelin basic protein is encephalitogenic in mice expressing H-2q and H-2s antigens. Six of 13 encephalitogen-specific T-cell clones were shown to express the variable beta-chain (V beta) 17a gene product (KJ23a+), whereas seven clones were KJ23a-. Both KJ23a+ and KJ23a- subpopulations were encephalitogenic in SJL/J mice when adoptively transferred. Depletion of KJ23a+ cells in vivo with the administration of the antibody KJ23a suppresses experimental allergic encephalomyelitis induced with KJ23a+ T-cell lines. However, experimental allergic encephalomyelitis induced with either (i) encephalitogenic peptide p89-101, (ii) intact myelin basic protein, or (iii) KJ23a- T cells reactive to p89-101 cannot be prevented with monoclonal antibody KJ23a. These data indicate that in spite of the V beta 17a gene expression in a relatively large proportion of p89-101-specific T cells, such V beta gene use is not essential for the induction of experimental allergic encephalomyelitis in SJL/J mice. These results contrast with the predominance of V beta gene use (V beta 8.2) in T cells reactive to the encephalitogenic fragment (pR1-11) in PL/J mice. One reason for this lack of dominant use of a particular T-cell receptor V beta gene family in the autoimmune response to myelin basic protein in SJL/J mice stems from the observation that two encephalitogenic epitopes exist in p89-101. KJ23a- T cells are stimulated by the deleted peptide p89-100, whereas KJ23a+ T cells are not. Thus, in the response to an encephalitogenic fragment of myelin basic protein containing two nested epitopes, at least two distinct T-cell receptor V beta genes are expressed. These distinct T-cell subpopulations can each trigger experimental allergic encephalomyelitis. These findings have implications for therapy of autoimmune disease with antibodies to the T-cell receptor gene products.

Animals↗
PubMed1988

In vitro proliferative responses and antibody titers specific to human acetylcholine receptor synthetic peptides in patients with myasthenia gravis and relation to HLA class II genes.

To investigate which parts of the acetylcholine receptor are involved in the initiation and development of myasthenia gravis (MG), peptides representing different sequences of the human acetylcholine receptor alpha-subunit were synthesized. These peptides were tested for their ability to stimulate T cells of myasthenic patients and healthy control patients in proliferation assays and to bind to sera antibodies. Three of eight peptides discriminated significantly between the two groups in the proliferation assay, as well as in their ability to bind to serum antibodies. HLA-DR3 and DR5 were associated with proliferative responses to specific AChR peptides in the group of myasthenics. Acetylcholine receptor epitopes that might play a specific role in myasthenia gravis thus were demonstrated.

Amino Acid Sequence↗
PubMed1987

Importance of immunoglobulin isotype in therapy of experimental autoimmune encephalomyelitis with monoclonal anti-CD4 antibody.

Experimental allergic encephalomyelitis (EAE) is an autoimmune disease mediated by CD4+ T cells. Prior studies have established that monoclonal anti-CD4 antibodies can reverse EAE. To determine whether immunoglobulin isotype plays a role in the therapy of EAE with anti-CD4 antibody, an isotype switch variant family of the mouse IgG1 anti-rat CD4 antibody W3/25 was isolated with the fluorescence-activated cell sorter. The IgG1, IgG2b, and IgG2a W3/25 isotype variants all had identical binding capacities for rat CD4+ T cells. Although all three W3/25 isotypes showed some beneficial effects in the amelioration of EAE, the IgG1 and IgG2a W3/25 antibodies were superior to the IgG2b W3/25 in the treatment of EAE. Multiparameter fluorescence-activated cell sorter analysis of T cell subpopulations from treated rats showed that none of the antibodies of the W3/25 isotype switch variant family substantially depleted CD4+ target cells in vivo. These experiments demonstrate that immunoglobulin isotype is important in the monoclonal antibody therapy of autoimmune disease. They indicate that therapy of EAE may be successful without a major depletion of CD4+ lymphocytes. Immunotherapy may be optimized by selecting an appropriate isotype of a monoclonal antibody.

Animals↗
PubMed1987

Inhibition of experimental autoimmune thyroiditis in mice by anti-I-A antibodies.

Experimental autoimmune thyroiditis is induced in mice by immunization with thyroglobulin emulsified in Freund's complete adjuvant. The disease is characterized both by thyroid infiltration with mononuclear cells and by circulating thyroglobulin antibodies. The magnitude of the thyroid infiltration and the titer of thyroglobulin antibodies are controlled by genes in the I-A subregion of the major histocompatibility complex (H-2). We investigated the in vivo effect of monoclonal anti-Ia antibodies on experimental autoimmune thyroiditis in susceptible mice. Antibodies were given around the time of immunization, later after immunization, and to mice with established disease. Monoclonal antibody produced by the hybridoma line 10-3.6 (anti-I-Ak, s, u, v, z, f) completely prevented both production of thyroglobulin antibodies and thyroid infiltrates, when given shortly before or at the time of antigen administration. This effect was dose-dependent and this monoclonal antibody decreased the severity of the disease when given after the antigen challenge but did not fully suppress established thyroiditis. The same antibody markedly decreased the number of B lymphocytes in the spleen and decreased the thyroglobulin-induced spleen cell proliferation when either given in vivo or added in vitro to cell cultures. Antibodies produced by the hybridoma line 11.2.12 (anti-I-Ak) did not show an inhibitory effect on the disease. These experiments suggest that in this model of murine thyroiditis anti-Ia antibodies act on antigen-presenting cells. Furthermore, only one monoclonal antibody, anti-Ia, suppressed the immune response to thyroglobulin, suggesting a possible role for the isotype and specificity of anti-Ia antibody.

Animals↗
PubMed1987

Comparison of antigen specificity, class II major histocompatibility complex restriction, and in vivo behavior of myelin basic protein-specific T cell lines and clones derived from (BALB/c x SJL/J) mice.

Immunization with myelin basic protein (BP) causes experimental allergic encephalomyelitis (EAE) in certain strains of mice. SJL/J (H-2s) is the prototype sensitive strain. Although BALB/c (H-2d) is resistant to EAE through use of an identical immunization protocol, (BALB/c x SJL/J)F1 hybrid mice develop EAE after immunization with BP. T cell clones specific for BP have been isolated from a highly encephalitogenic line of (BALB/c x SJL/J)F1 hybrid T cells raised against bovine BP. The clones were examined for their H-2 restriction and specificity for heterologous forms of BP (mouse, rat, and bovine BP). The results revealed the clones cross-reacting with mouse (self) BP were almost always restricted to F1 hybrid class II major histocompatibility complex (MHC) elements. In contrast, mouse cross-reactive clones derived from a nonencephalitogenic (BALB/c x SJL/J) T cell line raised against rat BP were largely restricted to H-2d elements. These clones did not cross-react with bovine BP. Four additional lines were generated by carrying the original rat and bovine F1 T cell lines on parental antigen-presenting cells thus generating lines biased toward homozygous (SJL/J, H-2s, or BALB/c, H-2d) restriction elements. These "parentally restricted" T cell lines did not induce EAE when injected in vivo. These results suggest that in this F1 strain sensitivity to T cell-induced EAE is associated with epitopes on murine BP that associate with F1 class II MHC restricting elements. In contrast, nonencephalitogenic T cell lines contain a high proportion of murine cross-reactive clones restricted to H-2d, the haplotype of the classically resistant BALB/c mouse. This work illustrates the use of T cell lines and clones in a model system to further analyze the role of MHC restriction elements in autoimmune disease occurring in heterozygous individuals.

Animals↗
PubMed1987

T cell specificity for class II (I-A) and the encephalitogenic N-terminal epitope of the autoantigen myelin basic protein.

The role of class II restriction in T cell recognition of an epitope of the autoantigen myelin basic protein (MBP) has been investigated. Encephalitogenic PL/J(H-2u) and (PL/J X SJL/J(H-2s))F1 ((PLSJ)F1) clones, isolated after immunization with intact MBP, recognize the N-terminal 11 amino acid residues of MBP in association with I-Au class II molecules. The synthetic peptide MBP 1-11 has been tested in vivo for induction of EAE. Clinical and histological EAE occurs in PL/J and (PLSJ)F1 mice but not SJL/J. The class II restriction of T cells primed with MBP 1-11 has been examined in primary cultures in vitro. Similar to encephalitogenic T cell clones, isolated after continuous selection in vitro, the population of MBP 1-11-specific proliferative PL/J and (PLSJ)F1 T cells, recognize this epitope in association with I-Au class II molecules. Not all MBP-specific T cell clones which are restricted to I-Au class II molecules cause autoimmune encephalomyelitis. The specificity of these non-encephalitogenic clones has been examined in this report. These clones also recognize MBP 1-11. Thus recognition of an encephalitogenic T cell epitope is not sufficient for induction of EAE.

Animals↗
PubMed1987

Depletion of T-4+ lymphocytes with monoclonal antibody reactivates toxoplasmosis in the central nervous system: a model of superinfection in AIDS.

Central nervous system toxoplasmosis causes disability and death in up to 30% of patients with acquired immune deficiency syndrome (AIDS). The source of the toxoplasma infection in these patients and the specific immune deficit that allows for this virulent form of the infection are unknown. By using a mouse model of toxoplasmosis, we found that selective depletion of T-4+ lymphocytes (CD4+ T cells) produces overwhelming infection and death in both acute and chronic toxoplasmosis. However, the pattern of infection is remarkably different in chronically infected mice as compared with acutely infected mice when the mice are depleted of CD4+ T cells. During acute infection loss of the CD4+ T cell population leads to severe systemic infection with only mild disease in the brain. In chronically infected mice depleted of CD4+ T cells, death follows severe CNS damage due to toxoplasma infection with only minor systemic involvement. In chronically infected mice treated with anti-CD4 monoclonal antibody, reactivation of the toxoplasma infection occurs despite high titers of circulating antitoxoplasma antibody. In parallel with these results in mice, CNS toxoplasmosis in AIDS patients may be due to reactivation of infection acquired much earlier in life.

Animals↗
PubMed1987

Monoclonal anti-I-A antibody reverses chronic paralysis and demyelination in Theiler's virus-infected mice: critical importance of timing of treatment.

Susceptibility to demyelination caused by the WW isolate of Theiler's murine encephalomyelitis viruses is linked to class II genes of the major histocompatibility complex. SJL/J (H-2s) mice, expressing only I-As class II gene products of the major histocompatibility complex, are highly susceptible to Theiler's murine encephalomyelitis virus infection with the WW virus isolate, with chronic paralysis and severe inflammation and demyelination in the central nervous system. The effect of in vivo administration of anti-I-As monoclonal antibodies on Theiler's murine encephalomyelitis virus infection was observed. SJL/J mice were treated in various protocols pre- or postinfection. Anti-I-As monoclonal antibody reversed chronic paralysis and reduced inflammation and demyelination when given after the establishment of persistent infection. The effect was long lasting, but clinical signs, inflammation, and demyelination recurred 2 months after treatment ceased. Anti-I-As antibodies had no effect on viral titers within the central nervous system. The timing of the administration of monoclonal antibodies was critical. Administration of anti-I-As before the establishment of the persistent infection resulted in fatal encephalitis.

Animals↗
PubMed1987

Susceptibility to multiple sclerosis associated with an immunoglobulin gamma 3 restriction fragment length polymorphism.

Susceptibility to multiple sclerosis (MS) has been linked to the immunoglobulin G (Gm) markers as well as HLA-DR genes. We have used a genomic Ig gamma 1 probe which detects polymorphisms in the gamma 1, gamma 2, gamma 3 and pseudogamma genes to identify restriction fragment length polymorphisms associated with MS. A negative association was found between a 5.9-kilobase (kb) Bst EII gamma 3 fragment and MS. Southern blot analysis of genomic DNA revealed the presence of this fragment in 84 of 140 (60.0%) controls, but in only 17 of 59 (28.8%) MS patients. The frequency of the fragment in 47 myasthenia gravis and 16 Graves' disease patients was similar to that in controls, 60.0 and 62.5%, respectively.

Gene Frequency↗