Comparative Studies on the In Vitro Decidualization Process in the Baboon (Papio anubis) and Human1

Abstract

The process of decidualization involves the morphological and functional transformation of stromal fibroblasts to decidual cells. The objective of this study was to define appropriate in vitro culture conditions required for decidualization of baboon stromal cells. Parallel studies were also done with human endometrial stromal cells for comparative analysis. Human stromal cells produced prolactin and insulin-like growth factor-binding protein (IGFBP)-1 in response to hormones (estradiol-17beta [36 nM], medroxyprogesterone acetate [1 microM], and relaxin [100 ng/ml]), and production was enhanced in the presence of 0.1 mM dibutyryl cAMP (dbcAMP). By contrast, baboon cells did not produce any detectable levels of prolactin, even in the presence of hormones and dbcAMP. IGFBP-1 expression in baboon stromal cells was detectable by Day 6 of hormone and dbcAMP treatment and increased exponentially thereafter. In both human and baboon stromal cells, alpha smooth muscle actin (alphaSMA) expression, an early marker for decidualization in the baboon in vivo, was induced spontaneously under normal culture conditions. Furthermore, a decrease in alphaSMA expression was observed in cells producing high levels of IGFBP-1. Human cells produced significant levels of IGFBP-1 (p < or = 0.01) in response to short-term dbcAMP treatment (48 h) after 2 and 12 days of hormone treatment. However, baboon stromal cells required 17 days of hormonal treatment before cells became responsive to short-term dbcAMP treatment (p < or = 0.01). Finally, human endometrial stromal cells expressed the protein kinase A regulatory subunits RIalpha, RIbeta, RIIalpha, and RIIbeta whereas baboon stromal cells expressed RIalpha, RIIalpha, and RIIbeta. No difference in the mRNA expression of these isoforms was observed in decidualized or nondecidualized cells of either human or baboon endometrium. Our observations indicate that baboon stromal cells can be induced to decidualize in vitro and that this requires dbcAMP in addition to hormones. This is the first report demonstrating in vitro decidualization in a nonhuman primate.

Modulation of the baboon ( Papio anubis ) uterine endometrium by chorionic gonadotrophin during the period of uterine receptivity

“…Immunostaining of serial sections obtained in this study with a monoclonal antibody to ␣SMA (14,20) showed that the stromal fibroblasts directly below the epithelial plaques and luminal epithelium of hCGtreated baboons stained intensely for ␣SMA (Figs. 2C and 3C).…”

“…The sense primer sequence was 5Ј-CCC CCA GAC CAA GCA GGA CCT GGA GCT CCC 3-Ј, and the antisense primer was 5Ј-ATC GTC CTG CAC CAG GAC TCT GGC CAG GTA-3Ј. The histone 3.3 PCR product was coamplified with glycodelin and served as an internal standard (20).…”

“…The RT-PCR was performed as previously described for baboon endometrial tissues (20). The RT-PCR procedure for glycodelin was optimized with RNA isolated from the endometrium of an early pregnant baboon.…”

Multipotent properties of myofibroblast cells derived from human placenta

“…PCR primers specific for osteopontin (according to Zhang et al 2004; 169 bp product), fatty acid binding protein-4, FABP-4 (according to Larson et al 2004;387bp product), and collagen II (according to Zhang et al 2004; 394 bp product) were used in 50pmol concentration. The constitutively expressed histone H3.3 was used in 10 pmol primer concentration (primers according to Kim et al 1998). PCR products were created using 32 cycles consisting of at 94 °C (1min), then 60 °C (55 °C for osteopontin) (2min), then 72 °C (3min), followed by 15 min of final extension at 72 °C.…”

The role of chorionic gonadotropin and Notch1 in implantation

“…Differentiation into decidual cells is important for control of endometrial vascularization and involves vasodilation and angiogenesis in the endometrium [48]. During the process of decidualization, endometrial stromal fibroblasts transform morphologically and biochemically into polygonal, secretory cells and begin to express specific decidual proteins such as prolactin and insulin like growth factor binding protein-1 (IGFBP-1) [49]. Although the morphological changes are useful predictors of successful implantation, the molecular mechanisms underlying them are largely unknown and remain to be elucidated.…”