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F S Galin

Publications and source records attributed to F S Galin.

13 recordsLinked to original sources
PubMed2001

Prevention and reversal of experimental autoimmune myasthenia gravis by a monoclonal antibody against acetylcholine receptor-specific T cells.

We have recently described an algorithm to design, among others, peptides with complementarity contour to autoimmune epitopes. Immunization with one such peptide resulted in a monoclonal antibody (mAb), termed CTCR8, that specifically recognized Vbeta15 containing TCR on acetylcholine receptor (AChR) alpha-chain residue 100-116-specific T cells. CTCR8 was found to label the cell surface of AChR100-116-specific T cell lines and clones, immunoprecipitate the TCR from such cells, and block their proliferative responses to AChRalpha100-116. In the present report, we have found that there is a marked reduction in IFN-gamma and no effect on IL-10 production in a CTCR8-treated AChRalpha100-116-specific T cell line. Interestingly, when AChR100-116-primed, primary T cells were stimulated with peptide and treated with CTCR8, there was once again inhibition of IFN-gamma but also marked stimulation of IL-10 production. The change in the Th1/Th2 cytokine profile was paralleled by a reduction in AChR-specific IgG2a and IgM with no effect on IgG1. Remarkably, the most profoundly inhibited Ab population was that which causes experimental autoimmune myasthenia gravis (EAMG) by reaction with the main immunogenic region (alpha61-76) of the AChR. Based on these results, CTCR8 was tested for prophylactic and therapeutic effects in EAMG. EAMG induced by immunization with purified native Torpedo AChR was both inhibited and reversed by CTCR8. These findings suggest a means to produce therapeutic mAb for the treatment of autoimmune diseases.

Animals↗
PubMed2001

An IgM anti-MBP Ab in a case of Waldenstrom's macroglobulinemia with polyneuropathy expressing an idiotype reactive with an MBP epitope immunodominant in MS and EAE.

In a previously described case of Waldenstrom's Macroglobulinemia, complicated by polyneuropathy, the IgM/lambda monoclonal antibody (mAb) was highly reactive with myelin basic protein (MBP). Given our demonstration that V lambda x, a recently described murine lambda variable region gene product, can itself bind MBP as well as confer MBP reactivity to an Ab, the possibility of a shared idiotypy between murine V lambda x and this human IgM/lambda anti-MBP was investigated. We characterized the epitope specificity of the macroglobulinemia patient's MBP-reactive IgM/lambda using indirect ELISA procedures with MBP, a citrullinated isomer of MBP termed C8, or peptide fragments of MBP as the coating antigens and monospecific Ab to V lambda x as the secondary Ab. The patient's MBP-reactive IgM/lambda was recognized by Ab specific for V lambda x and, like murine mAb containing V lambda x bound human MBP but not MBP-C8 nor other common autoantigens such as DNA, thyroglobulin, or actin. The anti-MBP reactivity was selective for MBP peptide 90-170 and preferentially recognized MBP peptide 84-96. Thus, the patient's macroglobulin and perhaps certain other human Ab with a 'V lambda x idiotype' bind to MBP peptide residues 84-96, an immunodominant peptide in multiple sclerosis patients. Such binding may be involved in the pathogenesis of neural damage in patients with neuroimmunologic disorders related to plasma cell dyscrasias or autoimmunity.

Animals↗
PubMed1999

Highly related immunoglobulin light chain sequences in different multiple sclerosis patients.

Although immunoglobulin G and free light (L) chains of oligoclonal origin in cerebrospinal fluid (CSF) are the most common immunologic abnormalities in multiple sclerosis (MS), it is unknown whether homologous CSF L chain sequences are present in different individuals with MS. Using Southern blotting, a particular kappa (kappa) L chain variable region (V) probe was recently found to hybridize to Vkappa cDNA from CSF B cells from almost one half of the MS patients tested but only 10% of normal or other neurologic disease controls [Zhou, S.-R., Maier, C.C., Mitchell, G.W., LaGanke, C.C., Blalock, J.E., Whitaker, J.N., 1998. A cross-reactive idiotope in cerebrospinal fluid cells in multiple sclerosis: further evidence for the role of myelin basic protein. Neurology 50, 411-417.] Here, we report that this likely results from remarkable sequence similarity in certain Vkappa from CSF B cells from different individuals with MS. The high degree of sequence homology even extended to all three complementarity determining regions (CDR) which in part form an antibody combining site. In addition, marked sequence homology was observed between the light chains from the MS patients and those from certain mouse antibodies against myelin basic protein (MBP). The results establish, in principle, that the same or very similar kappa light chain variable regions can be shared between CSF B lymphocytes from different individuals with MS as well as with certain antibodies against MBP.

Amino Acid Sequence↗
PubMed1996

Prevention of experimental autoimmune myasthenia gravis by a monoclonal antibody to a complementary peptide for the main immunogenic region of the acetylcholine receptors.

We have previously reported that a complementary peptide (denoted RhCA 67-16), encoded by RNA complementary to that of the Torpedo acetylcholine receptor (AChR) main immunogenic region (MIR), AChR residues alpha 61-76, induces polyclonal and monoclonal Ab reactive with Ig against the AChR MIR. RhCA 67-16 vaccination also protected against the development of experimental autoimmune myasthenia gravis (EAMG) in Lewis rats. In the present report, we found that a mAb (denoted TCM 240, IgG1 kappa) against RhCA 67-16 recognized three different idiotypic Ab (mAb 6, mAb 35, and mAb 198), which were previously reported by others to recognize the AChR MIR and to cause EAMG. Based on these results, TCM 240 was tested for prophylactic effects in EAMG. EAMG induced passively by mAb 35 was inhibited by simultaneous injection with TCM 240. The disease severity was inversely paralleled by the ratio of mAb 35 to TCM 240. EAMG induced by immunization with purified native Torpedo AChR was also inhibited by TCM 240, but not a control mAb. The inhibitory effect of TCM 240 on actively induced EAMG occurred without significantly lowering the overall AChR Ab levels, which indicates a limited repertoire of disease-causing Ab in EAMG and perhaps MG. Such findings suggest the existence of an EAMG-associated Id and also support the concept of an MIR. In a more general sense, these results demonstrate that prophylactic and perhaps diagnostic mAb for autoimmune diseases can be produced by immunization with complementary peptides for disease-associated epitopes.

Amino Acid Sequence↗
PubMed1996

Murine V lambda x and V lambda x-containing antibodies bind human myelin basic protein.

Myelin basic protein (MBP) is highly immunogenic and a known autoantigen capable of inducing experimental allergic encephalomyelitis (EAE), the animal model of multiple sclerosis. We have previously described a murine monoclonal antibody (mAb), F28C4, directed against the encephalitogenic MBP peptide acetyl (Ac) 1-9, which contains a V lambda x light chain. Considering the rarity of V lambda x usage, we determined whether other Abs having V lambda x light chains shared similar antigen (Ag) specificity. We screened a panel of V lambda x-containing monoclonal and polyclonal Abs, of unknown specificity for reactivity with MBP. All such Ab, but not heavy chain isotype matched controls, bound MBP but were not polyreactive with other potential self Ags. The binding of a recombinant form of V lambda x alone to MBP demonstrated the important contribution of the V lambda x light chain to the reaction. With the exception of mAb F28C4 which recognizes MBP Ac1-9, the epitope specificity of all other V lambda x-bearing Abs was localized to MBP residues 25-34. These results demonstrate a unique association between V lambda x expression and MBP reactivity. Given that V lambda x shares sequence homology with T cell receptors (TCR) from encephalitogenic T lymphocytes, these results imply a potential role for V lambda x in the pathogenesis of EAE.

Amino Acid Sequence↗
PubMed1996

Preferential association of V lambda x light chains with gamma 2a heavy chains in naturally occurring human myelin basic protein reactive antibodies.

Active immunization with myelin basic protein (MBP) induces experimental allergic encephalomyelitis (EAE) in a variety of animal species, including rats and mice. We have previously described the ability of the newly described mouse lambda (lambda) variable (V) region V lambda x, to confer MBP reactivity to an Ab. In this report, we have evaluated the heavy (H) chain isotype distribution of V lambda x-bearing Abs in normal mouse serum. We demonstrate a biased H chain isotype association with V lambda x light (L) chains with a skewing towards gamma 2a and 2b isotypes. The IgG2a restriction in normal mouse Igs is even more evident in V lambda x-containing Abs that bind MBP. This was confirmed by the ability of purified polyclonal IgG2a Abs to bind MBP and the finding that most or all of the IgG2a Abs that bind MBP seem to harbor a V lambda x L chain. The specificity of naturally-occurring V lambda x-bearing Abs with MBP can be localized to a particular epitope encompassing residues 25-34 of the MBP molecule. Furthermore, virtually all of the reactivity of V lambda x-containing Abs with MBP peptide 25-34 is associated with the gamma 2a isotype. Collectively, these results suggest that the interaction of V lambda x with MBP seems to be facilitated by an association with gamma 2a which may reflect preferred VH usage by this isotype. Such unique pairing of particular H chains with V lambda x L chains in Abs that bind MBP may be indicative of a new B-cell component involved in the pathogenesis of EAE.

Animals↗
PubMed1994

A V lambda x-bearing monoclonal antibody with similar specificity and sequence to encephalitogenic T cell receptors.

The fine specificity of mAb F28C4 to myelin basic protein (MBP), acetyl residues 1-9, has been compared with the previously described specificity of an encephalitogenic T cell clone, PJR-25. F28C4 has been found to express a cross-reactive idiotope (CRI) that is shared with MBP acetyl peptide 1-9-specific TCR. The CRI seems to be located at or near the Ag-combining site of F28C4 and the TCR and, thus, might possibly result from overlapping epitope specificity. We tested the fine epitope specificity of F28C4 by using alanine-substituted peptide analogues and found that residues critical for TCR recognition, Cln3 and Pro6, are also necessary for F28C4 recognition. By using nuclear magnetic resonance, we found that the MBP acetyl peptide 1-9 binds F28C4 in an extended conformation and that the central residues are more tightly bound than the terminal residues, much like the MBP-TCR interaction. Furthermore, sequence homology (75% overall) was found between the regions that contained CDR3 of F28C4 VL and VH and the VDJ junction of the TCR V beta. This homology is not shared by other Ig CDR3 regions and arises, in part, because F28C4 uses an unusual V lambda light chain, V lambda x. Thus, F28C4 shares a CRI with the TCRs, possibly as a result of having similar fine epitope specificity and sequence homology. The anti-CRI mAb can down-modulate experimental allergic encephalomyelitis; thus, it is possible that Abs that are similar to F28C4 may play an important immunoregulatory role in experimental allergic encephalomyelitis in vivo.

Amino Acid Sequence↗
PubMed1991

Corticotropin-releasing factor upregulates expression of two truncated pro-opiomelanocortin transcripts in murine lymphocytes.

Lymphocytes harbor a pro-opiomelanocortin (POMC) mRNA. In this report, a novel procedure was used to study the exonic arrangement of this transcript in lymphocytes. Poly(A)+ mRNA, purified from both corticotropin-releasing factor (CRF)-treated and nontreated lymphocytes, was selectively reverse-transcribed using an antisense oligonucleotide primer complementary to the 3' junction of the translated/nontranslated region of exon 3 of POMC. Alkaline agarose gel analysis of first-strand cDNA synthesis showed an upregulation of POMC transcripts in CRF-treated cells. This first-strand cDNA was amplified in a polymerase chain reaction (PCR) using the complementary antisense primer and selective sense primers homologous to the 5' ends of exons 1, 2, and 3, as well as a region immediately 5' to the ACTH/beta-lipotropin coding region of exon 3 of pituitary POMC. Primers directed at exons 1 and 2 did not amplify a POMC product in nontreated control or CRF-treated cells. However, with both treated and nontreated cells, the internal exon 3 primer amplified the expected size exon 3 DNA fragment (approximately 549 bp). Interestingly, a primer directed at the 5' end of exon 3 apparently did not amplify a POMC product in nontreated cells but did amplify a full-size POMC exon 3 from CRF-treated cells (approximately 615 bp). However, upon reamplification of the original PCR products from nontreated cells, full-length exon 3 product was also observed. Southern gel analysis using a pituitary POMC cDNA probe showed that all of the above PCR products were POMC-related. The results of this study show that lymphocytes basally transcribe at least two POMC transcripts that are upregulated by CRF. These two transcripts lack exons 1 and 2 but contain either part or all of exon 3. The smaller exon 3 transcript was the most abundant transcript under all conditions examined.

Adrenocorticotropic Hormone↗
PubMed1991

Detection of growth hormone and growth hormone-releasing hormone-related messenger RNA in rat leukocytes by the polymerase chain reaction.

To validate that growth hormone (GH) and growth hormone-releasing hormone (GHRH) can be produced by leukocytes, we have assessed the presence of GH and GHRH-related mRNA in leukocyte cultures by reverse transcription and the polymerase chain reaction. A sample of the polymerase chain reactions were size-fractionated by electrophoresis in a 0.8% agarose gel and examined with ultraviolet light after ethidium bromide staining. Single major DNA bands corresponding in length to the distance between the 5' ends of the two GH and GHRH specific primers, 603 base pairs and 260 base pairs, respectively, were obtained. The DNA bands hybridized specifically to GH- and GHRH-specific probes after Southern transfer to nitrocellulose. The identity of the GH polymerase chain reaction material was confirmed by restriction enzyme analysis. The results showed that GH and GHRH gene expression occurs in mononuclear leukocytes and support the idea that these neuroendocrine hormones may be common signal molecules between the immune and neuroendocrine systems.

Animals↗
PubMed1991

Role of leukocyte-derived pro-opiomelanocortin peptides in endotoxic shock.

The immune and neuroendocrine systems communicate and maintain homeostasis through various mechanisms, including the use of common signal and recognition molecules and the use of similar processes. This type of integrated network has profound effects on the onset and outcome of certain disease states, including endotoxic shock, in which a cascade of mediators influence the pathophysiologic responses. We have found that some of the common signal molecules shared between the immune and neuroendocrine systems are the peptide hormones adrenocorticotropin (ACTH) and endorphins (END). Our investigations have shown that these molecules are produced in vitro by cells of the immune system treated with various stimuli, including immunological stimuli such as bacterial lipopolysaccharide (LPS; endotoxin), virus infection (Newcastle virus; NDV), and the more classical neuroendocrine stimuli corticotropin-releasing hormone (CRH). We have proposed that the production of END by the peripheral immune system contributes to the pool of opioid peptides associated with the pathophysiology of endotoxic shock. Lymphocytes from LPS-sensitive C3HeB/FeJ mice but not LPS-resistant C3H/HeJ mice produce END and ACTH both in vitro and in vivo after treatment with LPS. Purification of the in vitro produced LPS-induced END from B-lymphocyte spleen cells followed by injections into both LPS-sensitive and -resistant mice elicits changes in body temperature and respiration rate. The spleen cells from the LPS-sensitive mice process ACTH and END differently depending on the stimulus for induction and the cell type in which the processing takes place. CRH or virus induce ACTH 1-39 and beta-END, whereas inductions with LPS yield major products of ACTH 1-22 to 1-26 and gamma-END, products that are for the most part unique to the immune system. We have shown that LPS induces a novel protease that functions optimally at pH 5 to cleave ACTH 1-39 into ACTH 1-22 to 1-26. This enzyme is present in LPS, but not mock or CRH-induced B cells from LPS-sensitive mice. The LPS-resistant mice did not possess this enzyme and therefore produced only the high-molecular-weight pro-opiomelanocortin (POMC)-like molecule. The inability to produce ACTH and END, presumably by their inability to process the precursor, may account, in part, for their lack of response to the LPS. The POMC peptides also may play an indirect role in orchestrating the pathophysiologic response, since both ACTH and END were shown to induce tumor necrosis factor (TNF). Our data strongly suggest that lymphocyte POMC peptides ACTH and END are important mediators in the overall response to endotoxin.

Adrenocorticotropic Hormone↗
PubMed1990

Nucleotide and amino acid sequence of lymphocyte-derived corticotropin: endotoxin induction of a truncated peptide.

To determine the degree of similarity between pituitary and lymphocyte proopiomelanocortin, the lymphocyte mRNA was reverse transcribed, cloned, and sequenced. Murine lymphocyte mRNA was first purified by oligo(dT)-cellulose affinity chromatography and was reverse transcribed by using a selective 3' antisense oligonucleotide primer directed at the boundary between the translated/nontranslated region on the 3' end of exon 3. This cDNA was then amplified in a polymerase chain reaction with selective primers containing Sal I and Kpn I restriction endonuclease sites. Amplified cDNA was then directionally ligated into M13mp18 and M13mp19 bacteriophage and was sequenced. The nucleotide sequence encoding this peptide was identical to that of mouse pituitary corticotropin (ACTH). Elevated levels of lymphocyte immunoreactive ACTH were then induced with bacterial lipopolysaccharide and the peptide(s) was purified by antibody affinity chromatography and reverse-phase high-performance liquid chromatography. The predominant immunoreactive ACTH species was approximately 3 kDa and its sequence was identical to pituitary ACTH(1-25). These results conclusively demonstrate that lymphocytes produce authentic ACTH and harbor its mRNA.

Adrenocorticotropic Hormone↗
PubMed1989

Cloning and sequencing of immunoglobulin variable-region genes using degenerate oligodeoxyribonucleotides and polymerase chain reaction.

A procedure is described for using the polymerase chain reaction (PCR) to amplify and clone the cDNA from mouse immunoglobulin (Ig) variable (V) regions. This method uses a set of universal 5'-oligodeoxyribonucleotide primers that are degenerate and allow for the amplification of Ig V-region sequences from gamma and mu heavy chains and from kappa light chains. Selective first-strand cDNA synthesis is performed using Ig constant region primers and then a PCR is achieved by using the appropriate universal 5'-primer. The universal Ig heavy-chain primer was used to amplify the V-region cDNA from gamma and mu isotypes and the universal light-chain primer was used to amplify three separate kappa light V-region sequences. This procedure was used to obtain Ig V-region gene sequences from hybridomas secreting IgG1/kappa, IgG2b/kappa and IgM/kappa isotypes.

Animals↗