Expression of Messenger Ribonucleic Acid and Presence of Immunoreactive Proteins for Epidermal Growth Factor (EGF), Transforming Growth Factor Alpha (TGFα) and EGF/ TGFα Receptors and 1251-EGF Binding Sites in Human Fallopian Tube1

Abstract

Reverse transcription polymerase chain reaction (RT-PCR) revealed that the Fallopian tubes express epidermal growth factor (EGF), transforming growth factor (TGF alpha), and EGF receptor (EGF-R) mRNA. The RT-PCR product was verified by restriction enzyme digestion analysis. Immunohistochemically, EGF, TGF alpha, and EGF-R were localized in Fallopian tubes by use of specific antibodies to human EGF, mature fragments of human TGF alpha, and monoclonal antibodies to the extracellular binding domain of EGF-R. The tubal epithelial cells were the primary site of immunoreactive EGF, TGF alpha, and EGF-R, which were present to a lesser extent in the stromal cells, smooth muscle cell layers, fibroblasts of serosal tissue, and arterial endothelial and smooth muscle cells. Using antibodies generated against the amino and carboxy termini of TGF alpha precursor produced a similar cellular distribution to that observed for mature TGF alpha. The intensity of immunoreactive TGF alpha with these antibodies was similar to that seen with EGF. The ciliated and nonciliated epithelial cells in the ampullary and isthmus regions immunostained with similar intensity for EGF, TGF alpha, and EGF-R. The immunostaining for EGF, TGF alpha, and EGF-R was cycle-dependent, was considerably higher during late proliferative and early-to-mid-secretory phases than during early proliferative and late secretory phases of the menstrual cycle, and was reduced during the postmenopausal period. Specimens obtained 5-12 yr after tubal ligation immunostained for EGF, TGF alpha, and EGF-R similarly to sections from unligated tubes taken during the same phase of the cycle. Quantitative autoradiography of 125I-EGF binding generated a pattern similar to that of immunostaining for EGF-R binding. Net grain density/100 microns 2 calculated for different cell types indicated that the epithelial cells had a significantly higher grain density than did other tubal cell types (p < 0.05) without the cycle dependency seen in the immunohistochemical study. In summary, the results demonstrate that the human Fallopian tube expresses mRNA and contains immunoreactive proteins for EGF, TGF alpha, and EGF-R as well as binding sites for 125I-EGF. The cycle dependency and lower immunostaining in postmenopausal tubes suggest a potential regulation of their expression by ovarian steroids. The results imply the importance of EGF/TGF alpha in a variety of tubal biochemical and physiological functions and possibly early embryonic development.

Expression of transforming growth factor alpha (TGF-α) gene in mouse embryonic development

“…The expression of EGF, TGF-ta, and the EGFR has been reported in fallopian tubes of humans (8,24,25). It has been shown that the expression of EGF and TGF-et mRNA in fallopian tissue is cycle dependent and influenced by ovarian steroids (8,25). Expression of both GFs has also been demonstrated in mouse uterine epithelial cells (26,27).…”

“…Our observations are consistent with these reports. The expression of EGF, TGF-ta, and the EGFR has been reported in fallopian tubes of humans (8,24,25). It has been shown that the expression of EGF and TGF-et mRNA in fallopian tissue is cycle dependent and influenced by ovarian steroids (8,25).…”

Human fallopian tube as an extraovarian source of relaxin: messenger ribonucleic acid expression and cellular localization of immunoreactive protein and 125I-relaxin binding sites

“…All the materials for RT-PCR, immunohistochemistry, and light microscope autoradiography were purchased from commercial sources as previously described [22]. Recombinant human relaxin (lot #W9809AX) and monoclonal antibody generated against human relaxin (lot #12600-54) were generously provided by Genentech Inc. (San Francisco, CA).…”

“…Dating of the specimens was based on histological evaluation and the patient's last menstrual period. Total RNA was isolated from fallopian tubes of the late proliferative (N = 2) and midsecretory (N = 2) phases and from CL (N = 2) of the midluteal phase of the menstrual cycle, from placenta (N = 2), and from fetal membranes/decidua (N = 2) as previously described [22]. Two micrograms of total RNA was subjected to first strand cDNA synthesis exactly as previously described [22], with PCR reaction conditions of 1.5 min at 94°C, 4 min at 54°C, and 3 min at 72 0 C for 40 cycles.…”

“…Total RNA was isolated from fallopian tubes of the late proliferative (N = 2) and midsecretory (N = 2) phases and from CL (N = 2) of the midluteal phase of the menstrual cycle, from placenta (N = 2), and from fetal membranes/decidua (N = 2) as previously described [22]. Two micrograms of total RNA was subjected to first strand cDNA synthesis exactly as previously described [22], with PCR reaction conditions of 1.5 min at 94°C, 4 min at 54°C, and 3 min at 72 0 C for 40 cycles. Restriction enzyme digestion was performed through use of Msp I (Hpa II), which is present only in the relaxin H1 sequence, and Hpa I, which is present in the relaxin H2 sequence [6].…”