Anti-apoptotic seminal vesicle protein IV inhibits cell-mediated immunity.

The in vitro effect of seminal vesicle protein IV (SV-IV) on the cytotoxic activity of human natural or acquired cellular immunity has been investigated by standard immunological procedures, a 51Cr-release cytotoxicity assay, and labeled-ligand binding experiments. The data obtained demonstrate that: (1) fluoresceinated or [125I]-labeled SV-IV binds specifically to the surface of human purified non-adherent monuclear cells (NA-MNC); (2)SV-IV suppresses the cytotoxicity of natural killer (NK) cells against K562 target cells, that of IL-2-stimulated NK (LAK) cells against DAUDI target cells, and that of VEL antigen-sensitized cytotoxic T lymphocytes (CTLs) against VEL target cells; (3) treatment of K562 target cells alone with SV-IV decreases their susceptibility to NK-induced lysis. These findings indicate that the protein SV-IV has a marked in vitro inhibitory effect on NK, LAK and CTL cytotoxicity, providing a better understanding of its immune regulatory functions

Antiapoptotic Seminal Vesicle Protein IV Induces Histamine Release from Human FcεRI+ Cells.

BACKGROUND: Seminal vesicle protein number 4 (SV-IV) is a small, basic, multifunctional, intrinsically disordered secretory protein synthesized in large amounts by rat seminal vesicle epithelium under androgen transcriptional control. SV-IV-immunorelated proteins occur in other rat tissues and in humans. METHODS: The in vitro effect of SV-IV on human FcepsilonRI+ cells was investigated by standard immunologic, biochemical and molecular biology procedures. RESULTS: SV-IV-induced histamine release from human basophils and lung mast cells without any influence on leukotriene C(4) release and cell migration. The histamine release rate was slower compared with that induced by anti-IgE, the temperature dependence of the event being similar. SV-IV-induced histamine release was Ca2+-dependent, suggesting a physiological interaction of the protein with FcepsilonRI+ cells. SV-IV and anti-IgE acted synergistically on the histamine release. SV-IV did not induce de novo synthesis of cytokines and growth factors (transforming growth factor-beta(1), interleukin-10, interleukin-13, tumor necrosis factor-alpha, vascular endothelial growth factor A) in FcεRI+ cells. CONCLUSIONS: SV-IV protein induces in human FcεRI+ cells the release of histamine, a proinflammatory, antiapoptotic and immunosuppressive biogenic amine. These data: (1) are consistent with the antiapoptotic and immunosuppressive properties of SV-IV; (2) confirm a regulatory feature of SV-IV on mammal inflammatory reactivity by either inhibiting the arachidonate cascade pathway or stimulating proinflammatory cytokine release from lymphocyte/monocytes and histamine from FcεRI+ cells; (3) raise the possibility of a protective role of SV-IV on implanting hemiallogenic blastocysts against maternal reactive oxygen species and immunological attacks at the uterine implantation site

Survivin promoter -31G/C polymorphism in oral cancer cell lines.

Survivin (SVV) is a protein that belongs to the inhibitor of apoptosis proteins (IAP) family and is involved in the G2/M phase progression of the cell cycle as a spindle-associated molecule. The biological features of this protein are well documented and its activity appears to be involved in mitochondria-dependent and -independent antiapoptotic pathways. Overexpression of SVV at the transcriptional and translational level has been associated with cancer, a multifactorial disorder in which the occurrence of a -31G to C polymorphism in the promoter region may significantly contribute to the development of this pathology. To verify this hypothesis, the occurrence of a single nucleotide polymorphism (SNP) in cis-acting cell cycle-dependent elements (CDEs) and in cell cycle homology regions (CHRs) of the survivin TATA-less promoter was investigated. A total of 23 oral squamous cell carcinoma (OSCC) cell lines and normal epithelium-derived normal human epidermal keratinocyte (NHEK) cell lines were analyzed by RFLP and direct DNA sequencing of their promoter region. Furthermore, survivin expression at the transcriptional and translational levels was evaluated in these cells by RT-PCR and Western blotting, respectively. The findings indicate that the presence of a G or C allele is not directly correlated to survivin expression, at the mRNA or at the protein level, at least in the OSCC lines analyzed in this study

SV-IV Peptide1–16 reduces coagulant power in normal Factor V and Factor V Leiden

Native Factor V is an anticoagulant, but when activated by thrombin, Factor X or platelet proteases, it becomes a procoagulant. Due to these double properties, Factor V plays a crucial role in the regulation of coagulation/anticoagulation balance

In vitro synthesis of different antigens related to the major secretory protein of the rat seminal vesicle epithelium.

Poly/A)+mRNA, prepared from rat seminal vesicles (RSV), was translated in a rabbit reticulocyte cell-free system. Among the translation products, three proteins (A, B and C), immunologically related to a major RSV secretory protein (RSV-IV), were detected. Recombinenta plasmids, harbouring specific cDNA sequences for RSV-IV, were used to positively select the mRNAs for antigens A and B. Phosphorylation sites were mainly detectable in the antigen B

The 11S rat seminal vesicle mRNA directs the in vitro synthesis of two precursors of the major secretory protein IV.

The 11s mRNA extracted from the rat seminal vesicles directs the synthesis of two different precursors of the major secretory protein RSV-IV. These two precursors are not interconvertible and seemingly originate from different translational events. Sucrose gradients, polyacrylamide gel electrophoresis and positive hybridization translation experiments do not allow the separation of the two putatively different mRNAs. It is concluded that the two RSV-IV precursors either derive from two extremely similar, but physically not separable mRNA species, or from two different modes of translation of the same mRNA molecule