High impact information on Nhp2l1

• A fertilization antigen, FA-1, was purified from either deoxycholate- or lithium diiodosalicylate-solubilized murine testes by immunoaffinity chromatography using a monoclonal antibody, MA-24, which inhibited fertilization in vitro [1].
• The FA-1 was recovered at high (11.4) or low (2.8) pH using stepwise elution procedures of the deoxycholate or lithium diiodosalicylate extracts, respectively [1].
• The FA-1 revealed a positive reaction with periodic-Schiff reagent and contained glucose and mannose, which together constituted 18.8% of the total antigen mass [1].
• The dialyzed FA-1 contained a major 23-kDa and a minor 48-kDa band when separated on both sucrose and cesium chloride gradients [1].
• Affinity-purified Fab' antibodies against lithium diiodosalicylate (LIS)-solubilized murine sperm extract and fertilization antigen (FA-1) reduced (p less than 0.01 to p less than 0.001) blastulation rates of in vitro cultured 2-cell murine embryos primarily because of an arrest of development at the morula stage [2].

Biological context of Nhp2l1

• The minimal amount of free anti-FA-1 antibodies present in sera did not bind to live sperm in the sperm immobilization technique, sperm agglutination technique, or immunobead binding technique and thus were incapable of affecting human sperm penetration of zona-free hamster ova (SPA) [3].
• Purified fertilization antigen (FA-1), protamine, and the lithium diiodosalicylate (LIS)-solubilized sperm preparation activated presensitized lymphocytes to secrete soluble mediators that activated macrophages and significantly inhibited sperm motility and embryonic development [4].
• In conclusion, our data indicate that FA-1 can induce an immune response that is germ cell-specific, directed against later stages of spermatogenesis [5].
• Also, the monoclonal Fab' antibodies to FA-1 antigen and phosphotyrosine residues significantly (P < 0.05) reduced sperm-zona pellucidae and the antibodies were preincubated with sperm before insemination and not vice versa [6].
• These results suggest that the tyrosine phosphorylation especially of FA-1 antigen has an important role in zona pellucida receptor recognition and binding [6].

Anatomical context of Nhp2l1

• Anti-FA-1 Fab' did not react with unfertilized or fertilized ova, but specifically identified two protein bands (approx. 53 and 25.7 kDa) on blots of 2-cell-embryo extract, one band (approx. 25.7 kDa) on morula extract, and one band (approx. 53 kDa) on blastocyst extract [2].
• None of the antisera reacted with any somatic tissue, indicating germ-cell specificity of FA-1 [5].
• The antibodies to FA-1 interact with sperm after penetration through epididymis (especially corpus and cauda regions) and vas deferens rather than through testes and seminal vesicles [5].
• The biodistribution studies of 125I-labeled anti-FA-1 IgG in mice revealed that the antibodies do not bind to somatic tissues such as blood cell, liver, heart, kidney, muscle, and gastrointestinal tissue and do not transudate into testes and seminal vesicle [5].
• The purified FA-1 antigen completely blocked sperm binding to zona pellucida (P < 0.0001) [6].

Associations of Nhp2l1 with chemical compounds

• Seven glycans with strong antitumor activities were obtained from 14 water-soluble, and 15 water-insoluble fractions: FIo-a, FA-1, FII-1, FIII-2, and FIII-2-a, -b, and -c. FIo-a and FA-1 were protein-containing glucogalactans associated with mannose and fucose [7].

Analytical, diagnostic and therapeutic context of Nhp2l1

• In a Western blot procedure, the anti-rFA-1 antibodies specifically recognized the protein band of approximately 47 kDa (dimeric form of cognate FA-1 antigen) only in the protein extract of testes and not in the extracts of somatic tissues tested, namely kidney, liver, intestine, spleen, muscle, heart, lung, brain, and ovary [8].
• Vaccination of female mice with recombinant fertilization antigen (FA-1) causes a long-term reversible contraceptive effect [9].
• The FA-1 was immunogenic in all three female rabbits tested and raised a high-titer antisera [enzyme-linked immunosorbent assay (ELISA) titers; 1:1,024 to 1:4,096] [5].
• The fertilization antigen (FA-1) isolated from murine testes demonstrated its dimeric form of 49,000 +/- 2,000 molecular weight (M.W.) or a monomer of 23,000 M.W. on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) [5].

References