Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0393754 (HSA)
 2,996 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Among the monoclonal antibodies generated against acrosome-reacted human sperm, HSA-5 was shown to react with a sperm antigen localized predominantly to the equatorial region of the acrosome of human sperm and to the head and tail of mouse sperm. This antibody reacted with the methanol-fixed sperm, but not with fresh live sperm. When purified by immunoaffinity column, a major protein band with a molecular mass of approximately 100 kDa on SDS gel was isolated from fresh human sperm extract. The immunospecificity of isolated human sperm protein to this monoclonal antibody was verified by enzyme-linked immunosorbent assay and Western blot analysis. This antigen, designated as HSA-5, was susceptible to proteolytic degradation and revealed multiple immunoreactive bands in Western blot analyses of some preparations. Mouse sperm homogenates showed a similar polymorphic pattern to that of human samples. The tissue specificity of this antigen was examined immunohistochemically using various mouse and human tissues. HSA-5 did not cross-react with any other tissues except for sperm in adult testes and epididymis. This antibody also showed no binding activity to testicular tissue sections from mice of 13 and 21 days of age. The results of our study suggest that the sperm antigen recognized by HSA-5 monoclonal antibody is a differentiation antigen, which is expressed postmeiotically in testicular sperm but not in any somatic tissues.
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PMID:Purification and characterization of a sperm antigen recognized by HSA-5 monoclonal antibody. 863 26

An 80-kDa human sperm antigen (80-kDa HSA) has been identified as a sperm protein responsible for inducing immunoinfertility. Immunization with the purified protein induced infertility in male and female rats. Immunohistochemical and immunofluorescent studies have demonstrated that the antigen is specific to spermatozoa. The present study describes the partial amino acid sequencing of 80-kDa HSA. The homogeneous protein was electrophoretically transferred onto a PVDF membrane and the excised band of 80-kDa HSA was used to determine the partial N-terminal amino acid sequence. The protein was then subjected to enzymatic digestion with endoproteinase Lys-C and endoproteinase Glu-C. The partial amino acid sequence of the major peptides thus obtained was determined. The digestion with endoproteinase Lys-C generated 4 major peptides, two of which showed partial sequence homology with lactoferrin. Endoproteinase Glu-C digestion produced 3 major peptides. The sequences of the 2 peptides were determined for which no matches were found in the databank. These results confirmed earlier observations that 80-kDa HSA is a sperm-specific protein that is chemically distinct from any other protein involved in normal physiological process. Earlier studies have demonstrated that it is antigenic, efficacious, conserved, and could be a promising candidate for the development of an antifertility vaccine.
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PMID:Partial amino acid sequencing of 80-kDa human sperm antigen (80-kDa HSA). 1169 47

Tyrosine phosphorylation has recently been associated with capacitation and suggested as a regulator of sperm movement, especially characterizing hyperactivation. The objective of this study was to verify if tyrosine phosphorylation of human sperm proteins was essentially required for the maintenance of motility as well as the development of hyperactivation. Washed sperm were incubated for 6 h in Ham's F10 + 0.35% HSA at 37 degrees C in 5% CO(2), with and without the tyrosine kinase inhibitors genistein, tyrphostin, erbstatin, or herbimycin A and the wide-spectrum kinase inhibitor staurosporin. The concentrations of the inhibitors used in the experiments did not induce sperm toxicity, as measured by membrane integrity and mitochondrial function assays. Samples incubated without the inhibitors (control), increased their tyrosine kinase activity (ELISA), the number and intensity of tyrosine-phosphorylated (PY) protein bands (Western blot), the incidence of PY-immunoreactive sperm (immunofluorescence), and some of the sperm motion characteristics (CASA), such as velocity (VEL), amplitude of lateral head displacement (ALH), and hyperactivation. Among the selective protein tyrosine kinase inhibitors, genistein was the most active and consistent, inhibiting sperm tyrosine kinase activity, PY proteins, incidence of PY sperm, and sperm motility and motion parameters, such as VEL, ALH, and hyperactivation. The rest of the kinase inhibitors decreased motion characteristics to a varied extent and had different effects on phosphorylation parameters. In general, they decreased PY phosphorylation of 2 proteins (83 and 54 kDa) present in whole sperm extracts, and two sets of proteins of low (39-49 kDa) and medium (55-87 kDa) molecular weight present in the Triton X-100-solubilized sperm protein fraction. This inhibition was evident regardless of the total tyrosine kinase activity of the samples or the incidence of PY-immunoreactive sperm. The described findings further support the association between motility and protein tyrosine phosphorylation in human sperm and point to certain proteins as the main linkers.
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PMID:Effect of tyrosine kinase inhibitors on tyrosine phosphorylation and motility parameters in human sperm. 1274 2

Sperm proteins are known to be associated with normal fertilization as auto- or iso-antibodies to these proteins may cause infertility. Therefore, sperm proteins have been considered to be the potential candidate for the development of antifertility vaccine. Some of the sperm proteins proved to be promising antigens for contraceptive vaccine includes lactate dehydrogenase (LDH-C4), protein hyaluronidase (PH-20), and Eppin. Immunization with LDH-C4 reduced fertility in female baboons but not in female cynomolgus macaques. Active immunization with PH-20 resulted in 100 per cent inhibition of fertility in male guinea pigs but it induced autoimmune orchitis. Immunization with Eppin elicited high antibody titres in 78 per cent of immunized monkeys and induced infertility but the immunopathological effect of immunization was not examined. Human sperm antigen (80 kDa HSA) is a sperm specific, highly immunogenic and conserved sperm protein. Active immunization with 80 kDa HSA induced immunological infertility in male and female rats. Partial N-terminal amino acid sequence of 80 kDa HSA (Peptide NT) and its peptides (Peptides 1, 2, 3 and 4) obtained by enzymatic digestion did not show homology with any of the known proteins in gene bank. Peptides NT, 1, 2 and 4 were found to mimic immunobiological activity of native protein. Passive administration of antibodies to peptides NT, 1, 2 and 4 induced infertility in male and female rats and peptide 1 was found to be most effective in suppressing fertility. Active immunization with keyhole limpet haemocynin (KLH) conjugated synthetic peptide 1 impaired fertility in all the male rabbits and six of the seven male marmosets. The fertility was restored following decline in antibody titre. All these findings on 80 kDA HAS suggest that the synthetic Peptide-1 of 80 kDa HSA is the promising candidate for development of male contraceptive vaccine.
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PMID:Development of antifertility vaccine using sperm specific proteins. 2567 47