Leukaemia inhibitory factor receptor and gp130 in the human Fallopian tube and endometrium before and after mifepristone treatment and in the human preimplantation embryo

Leukaemia inhibitory factor (LIF) is a cytokine, which is associated with reproductive processes such as embryo development and implantation. The objectives of this study were to detect the presence of LIF receptor (LIFR) and glycoprotein 130 (gp 130) in the human Fallopian tube, endometrium and preimplantation embryo and to study the effect of mifepristone on the expression of LIFR and gp130 in the Fallopian tube. Twenty-two healthy fertile women received a single dose of 200 mg mifepristone or placebo immediately after ovulation (LH + 2). Biopsies were obtained from the Fallopian tubes during laparoscopic sterilization once between days LH + 4 and LH + 6 and from endometrium once between days LH + 6 and LH + 8. Preimplantation embryos were received from couples undergoing in vitro fertilization treatment. Immunohistochemistry was used to detect the presence of LIFR and gp130 in the Fallopian tube, endometrium and preimplantation embryo. Real-time PCR was used to study LIFR and gp130 expression in the Fallopian tube and endometrium. LIFR and gp130 were localized in the Fallopian tube, preimplantation embryo and endometrium. LIFR was more abundant in the Fallopian tube than in the endometrium. In the blastocyst, the staining of gp130 was mainly localized in the inner cell mass, whereas LIFR was expressed in all cells. The presence of LIFR and gp130 in the Fallopian tube and preimplantation embryo indicates a role for LIF in communication between the embryo and the Fallopian tube. Mifepristone did not affect the expression of LIFR and gp130 in the Fallopian tube, nor in the endometrium suggesting that progesterone might not be directly involved in the regulation of LIFR or gp130.

Prostaglandin E2 and F2alpha receptors in the human Fallopian tube before and after mifepristone treatment

Prostaglandins are associated with several reproductive processes in addition to their effects on the vascular system and muscular contractility. The aim of this study was to gain information about the localization of the receptors for PGE(2) (EP1-EP4) and PGF(2alpha) (FP) in the human Fallopian tube and their regulation following treatment with mifepristone. Sixteen healthy fertile women received a single dose of 200 mg mifepristone or placebo immediately after ovulation (LH+2). Laparoscopic sterilization was performed on days LH+4 to LH+6. Biopsies were taken from the Fallopian tubes bilaterally. The expression of EP1, EP2, EP3, EP4 and FP was analysed using immunohistochemistry and RT-PCR. The co-localization of prostaglandin receptors and c-kit or e-nos was analysed using confocal microscopy. The effect of progesterone, mifepristone and prostaglandin on tubal contractility was studied. The presence of EP1-EP4 and FP in the Fallopian tube was detected using immunostaining. The receptors were expressed in serosal cells, luminal epithelial cells, and the muscular wall and vessels of the Fallopian tube. Co-localization studies showed that the endothelial cells stained positive for EP1-EP4 and FP and that co-localization was seen for EP4 and c-kit. Decreased contractility was seen after progesterone treatment, whereas increased contractility was seen after PGF(2alpha) and PGE(2) treatment. These data suggest that both the transport of the embryo and the communication between the embryo and the Fallopian tube involve the action of prostaglandins through EP and FP receptors in addition to the effect of prostaglandins on the vascular system and muscular contractility.

The newborn infant is protected by an innate antimicrobial barrier: peptide antibiotics are present in the skin and vernix caseosa

BACKGROUND

Peptide antibiotics are part of the surface defences against microbial intruders. However, the presence and significance of these innate immune effectors in the skin barrier of the newborn infant have not yet been appreciated. Erythema toxicum neonatorum is an inflammatory skin reaction of unknown aetiology and significance, commonly present in the healthy newborn infant.

OBJECTIVES

As peptide antibiotics are upregulated in inflammatory skin disorders, we hypothesized that this also could be the case in erythema toxicum. We also investigated if the vernix caseosa, a cream-like white substance present on the skin of the infant at birth, might contribute to host defences.

METHODS

The presence of the human antibacterial peptide LL-37 was investigated by immunohistochemistry and confocal imaging of skin biopsies from four 1-day-old infants with an erythema toxicum rash and four matched newborns without the rash. In addition, we analysed the expression of LL-37 and human beta defensin-1, an antibacterial peptide of epithelial origin, by reverse transcriptase-polymerase chain reaction. Finally, we screened for antibacterial components in vernix material obtained from six healthy newborns by inhibition zone assays.

RESULTS

All biopsies from the lesions of erythema toxicum showed a dense, nodular infiltrate with numerous LL-37-expressing cells located in the dermal layer and a clear localization of the peptide within CD15-expressing neutrophils, EG2-expressing eosinophils and CD1a-expressing dendritic cells. LL-37 was also found to be located in CD1a-expressing Langerhans cells and a positive staining for the peptide was seen throughout the whole epidermal layer, both in infants with and without the rash. Skin samples from infants with the rash of erythema toxicum showed a constitutive expression of human beta defensin-1, while the expression of LL-37 seemed to be induced. Furthermore, LL-37 and lysozyme were detected in the protein fractions derived from the vernix caseosa, and these fractions exhibited a clear antibacterial activity.

CONCLUSIONS

Peptide antibiotics are present in the vernix caseosa and in the skin of the healthy newborn infant, indicating effective innate immune protection already during fetal and neonatal life.

Specific localization of RBM1a in the nuclei of all cell types except elongated spermatids within seminiferous tubules of the human

Recent studies have indicated that at least three regions (AZF a-c) on the long arm of the Y-chromosome code for factors are involved in spermatogenesis. One of the candidate genes in the AZFb region is RBM1a, coding for a protein with an RNA binding motif. In this study, poly clonal antibodies raised against a 15 amino acid peptide, corresponding to residues 263-304 of the deduced amino acid sequence of RBM1a, has been used to localize the RBM1a protein in the human testis. Immunohistochemistry on normal human testis using this RBM1a antibody, localized the antigen to the nuclei of spermatogonia, primary spermatocytes, and round spermatids but not to the nuclei of elongated spermatids. The antibody also specifically identified the nuclei of Sertoli cells, although the fluorescence was not as strong as in the germ cell nuclei it identified. No specific fluorescence was seen in the nuclei of either peritubular, endothelial or Leydig cells. Western blot of normal human testicular tissue using the anti-RBM1a antibody gave rise to a single specific band of approximately 55 kDa, corresponding to the expected size of RBM1a. In view of its expression in germ cells, and because RBM1a has an RNA binding domain, RBM1a may be involved in RNA processing, such as RNA splicing or RNA export which are events necessary for normal spermatogenesis.

Erythema toxicum neonatorum: an immunohistochemical analysis

Erythema toxicum neonatorum is a benign rash of unknown etiology, present to various degrees in most term newborns and characterized by an accumulation of eosinophils in dermal lesions. The recruitment of leukocytes to tissues implicates the involvement of adhesion molecules, cytokines, and chemokines. We therefore performed immunohistochemistry on punch biopsy specimens from cutaneous lesions of ten 1-day-old infants with erythema toxicum using specific monoclonal antibodies directed against a variety of adhesion molecules, cytokines, chemokines, and cell type-specific membrane markers. Biopsy specimens of noninflamed skin from four matched newborns and four adults served as controls. The immunohistologic features of erythema toxicum in all 10 infants included a strong staining of the adhesion molecule E-selectin in the vessel wall and the presence of numerous inflammatory cells that were identified as dendritic cells (CD1a, CD83, HLA-DR, CD40, and ICAM-1 positive), eosinophils (EG2 positive), neutrophils (CD15 positive), macrophages (CD14, CD68, and Mac387 positive), and E-selectin-expressing cells. Furthermore, the lesions showed a high incidence of the proinflammatory cytokines interleukin (IL)-1alpha and IL-1beta and of the chemokines IL-8 and eotaxin. This immunologic activity was reduced or absent in noninflamed skin from newborn controls and adults. We conclude that there is an accumulation and activation of immune cells in the lesions of erythema toxicum, also present in noninflamed skin of 1-day-old infants, but to a lower level. The physiologic significance of the rash remains to be elucidated.

Human cervical ripening, an inflammatory process mediated by cytokines

An extensive remodelling process, referred to as cervical ripening, takes place in the cervical tissue during pregnancy and labour. It is recognized as softening and dilation of the cervical canal, and starts as a slow process during pregnancy, becoming rapid close to partum. In this study we focus on cytokines as possible mediators of this final remodelling. mRNA levels for interleukin (IL)-8, IL-6 and granulocyte colony-stimulating factor (G-CSF) were upregulated in the ripe postpartum cervical tissue (n = 8) compared to the unripe state (n = 9). Likewise, released cytokine concentrations increased from non-pregnant (n = 11) to the term-pregnant group (n = 13) with a further increase at partum (n = 16). IL-8 concentrations increased 4-fold from non-pregnant to term-pregnant (P<0.01), and a further 10-fold to postpartum state (P<0.0001). Concentrations of IL-6 and G-CSF were similarly increased. Specific IL-8 immunostaining was identified in the epithelia of pregnant cervical tissue (n = 7) and was most pronounced in the epithelia and stroma of postpartum tissue (n = 4). In conclusion, IL-8, IL-6 and G-CSF increase in the human cervix during the ripening process, indicating their important role in the cervical remodelling. These data demonstrate that cervical ripening is similar to an inflammatory process.