Pre–B-cell colony–enhancing factor is a secreted cytokine-like protein from the human amniotic epithelium

Abstract

Objective-The purpose of this study was to determine whether pre-B-cell colony-enhancing factor is a secreted cytokine in the human amnion and to study its chemotaxic and antiapoptotic properties.Study design-Pre-B-cell colony-enhancing factor secretion was studied from amniotic epithelial-like WISH cells and primary amniotic epithelial cells that were seeded on squares of immobilon-P membrane and stimulated with lipopolysaccharide or tumor necrosis factor-α , respectively. The pre-B-cell colony-enhancing factor protein was detected both intracellularly and after secretion, as bound to the membrane, by immunostaining and densitometry. Medium and cell lysates that were obtained from WISH cells that were treated with lipopolysaccharide alone or together with a pre-B-cell colony-enhancing factor antisense oligonucleotide to block pre-B-cell colony-enhancing factor translation were also analyzed for secreted pre-B-cell colony-enhancing factor by Western blotting and densitometry. A chemotaxic effect of pre-B-cell colony-enhancing factor on human neutrophils was compared with the chemoattractants interleukin-8 and N-FormylMet-Leu-Phe methyl ester in a rapid fluorescence-based neutrophil migration assay. Apoptosis was induced in primary amniotic epithelial cells and fibroblasts by actinomycin D (1 μg/mL); the antiapoptotic effects of pre-B-cell colony-enhancing factor on early apoptosis were measured by the annexin V assay, and the late effects were determined by measurement of nuclear matrix protein in the media.Results-Treatment of amnion cells that adhered to immobilon-P membrane to induce the secretion of pre-B-cell colony-enhancing factor showed significantly (P < .05) more pre-B-cell colonyenhancing factor protein surrounding the cells compared with the controls. Although the addition of lipopolysaccharide to cultured WISH cells caused the secretion of pre-B-cell colony-enhancing factor into the medium, co-treatment with an antisense oligonucleotide to pre-B-cell colonyenhancing factor obliterated it. Analysis of the cell lysates showed no significant change, which suggests that most of the pre-B-cell colony-enhancing factor protein had been secreted. No significant chemotaxic effects of pre-B-cell colony-enhancing factor were observed; however, pre-B-cell colony-enhancing factor treatment (100 ng/mL), together with actinomycin D, cancelled the early induction of apoptosis, although there was a dose-dependent and significant late antiapoptotic effect on primary amnion epithelial cells (P < .001) and fibroblasts (P < .01).Conclusion-Pre-B-cell colony-enhancing factor is a secreted protein from amniotic epithelial cells. Although it had no chemotaxic effects, it was antiapoptotic for both amniotic epithelial cells and fibroblasts and may protect these cells against apoptosis that is induced by chronic distension, labor, or infection. KeywordsPre-B-cell colony-enhancing factor; Cytokine; Secretion; Chemotaxis; Apoptosis Pre-B-cell colony-enhancing factor (PBEF) was first identified from activated periphera...

NAMPT (visfatin) in the chicken testis: influence of sexual maturation on cellular localization, plasma levels and gene and protein expression

“…In addition to altered subcellular localization, expression of NAMPT in myoid cells was influenced by sexual maturation. NAMPT gene expression appears to be mechanically sensitive in amniotic epithelial cells, with expression increasing in response to acute stretching (Nemeth et al 2000, Ognjanovic et al 2005. Furthermore, stretching-induced NAMPT expression protected the amniotic epithelial cells from apoptosis (Kendal-Wright et al 2008).…”

Adipocytokines as driving forces in rheumatoid arthritis and related inflammatory diseases?

“…In monocytes, it can induce proinflammatory cytokines such as IL-1, TNF, and IL-6 (23). In addition, visfatin/ PBEF protects fibroblasts and neutrophils from apoptosis (24). During polyclonal immune responses, visfatin/ PBEF production is increased in lymphocytes and stimulates their proliferation (25).…”

“…Visfatin/PBEF is induced by IL-6, oncostatin M, and TLR (59), e.g., in synovial fibroblasts, and seems to be involved in IL-6 trans-signaling (58). In addition, fibroblasts and neutrophils are protected from apoptosis by visfatin/PBEF (24,60). These data show that visfatin/PBEF not only is induced by proinflammatory factors but also induces inflammation and destruction-mediating factors in central cells relevant in RA pathophysiology as well as survival of inflammatory cells.…”

Visfatin levels in patients with severe pneumonia

“…TNF-α is found to be elevated at the early stage of SIRS, and increased at a higher level under MODS. It is indicated in studies [14,15] that inflammatory cytokines could regulate the production of visfatin, for example TNF-α could induce the expression of visfatin at the mRNA level, IL-6 and IL-8 could increase the genetic expression of visfatin, while visfatin could also induce the secretion of the above inflammatory cytokines in a dose-dependent way. But there are different points of view.…”

“…Kralisch et al [16] found that IL-6 could also inhibit the expression and synthesis of visfatin. Ognjanovic et al [15] discovered that exogenous IL-8 didn't affect the expression of visfatin. In this study, the level of visfatin in patients with severe pneumonia was positively correlated with TNF-α, but was not significantly correlated with IL-6 and IL-8.…”