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N Chegini

Publications and source records attributed to N Chegini.

At least 73 records · Page 4Linked to original sources
PubMed1994

Expression of transforming growth factor-beta (TGF beta) isoforms and TGF beta type II receptor messenger ribonucleic acid and protein, and the effect of TGF beta s on endometrial stromal cell growth and protein degradation in vitro.

Reverse transcription-polymerase chain reaction analysis of total RNA and immunocytochemical observations revealed that human endometrial glandular epithelial and stromal cells in primary culture express messenger RNAs and proteins for transforming growth factor-beta 1 (TGF beta 1), TGF beta 2, and TGF beta 3 as well as TGF beta type II receptor. The epithelial and stromal cells synthesize and secrete into their culture-conditioned medium 2.6 +/- 0.3 and 1.4 +/- 0.2 ng TGF beta 1/10(6) cells, respectively; after transient acidification of the medium, the TGF beta 1 levels were 18.1 +/- 0.4 and 7.8 +/- 0.7 ng/10(6) cells. These cells also contain specific binding sites for [125I]TGF beta 1, indicated by light microscope autoradiography. TGF beta s at 0.01-10 ng/ml neither stimulated or inhibited subconfluent quiescent stromal cells under serum-free condition nor altered the mitogenic action of 10% fetal bovine serum. However, in the presence of 2% fetal bovine serum, which induced half-maximal stimulation of [3H]thymidine incorporation, TGF beta 1 and TGF beta 2 at 0.1-0.5 ng/ml and TGF beta 3 at 0.1-2.5 ng/ml significantly stimulated the rate of [3H]thymidine incorporation into quiescent stromal cells (P < 0.005); they were ineffective at higher concentrations. TGF beta s did not have any effect on cell proliferation, as determined by cell counting; however, at 0.1 ng/ml and higher concentrations, TGF beta s significantly reduced the metabolic activity of stromal cells, as determined by colorimetric 3-(4,5-dimethylthiazol-2-yl)2, 5-diphenyltetrazolium bromide assay (P < 0.05). The stimulatory and inhibitory actions of TGF beta s in both assays were reversible using 5-10 micrograms/ml TGF beta 1- and TGF beta 2- and 3-6 micrograms/ml TGF beta 3-specific neutralizing antibodies. TGF beta 1 at 1 ng/ml had no significant effect on long-lived protein degradation, assayed by incorporation of [14C]valine into newly synthesized protein by stromal cells, and was similar to the effect of epidermal growth factor or platelet-derived growth factor-BB (10 ng/ml). The data suggest that the TGF beta expression by various endometrial cell types in an autocrine/paracrine manner acts as a negative regulator essential for restraining endometrial growth and transition from proliferation to differentiation stages during the secretory phase after mitogenic stimulation during the proliferative phase of the menstrual cycle.

Adult↗
PubMed1994

Human fallopian tube expresses granulocyte-macrophage colony stimulating factor (GM-CSF) and GM-CSF alpha and beta receptors and contain immunoreactive GM-CSF protein.

Using specific primers, 35S-40mer oligonucleotide probe and monoclonal antibody, reverse transcription polymerase chain reaction (RT-PCR), in situ hybridization, and immunohistochemical observations respectively revealed that human fallopian tube expresses granulocyte macrophage colony stimulating factor (GM-CSF) mRNA and protein, as well as GM-CSF alpha and beta receptors mRNA. The RT-PCR products revealed the predicted 286, 546 and 380 bp fragments for GM-CSF, GM-CSF alpha receptor and GM-CSF beta receptor respectively, which were further verified by restriction enzyme digestion analysis. Tubal epithelial cells in the ampullary and isthmus regions (ciliated and nonciliated) are the primary site of GM-CSF mRNA expression and its immunoreactive gene product, and present to a lesser extent in tubal stromal, smooth muscle, and arterial endothelial and smooth muscle cells. The in situ hybridization and immunostaining observations indicated that the expression of GM-CSF mRNA and protein appeared to be cycle dependent and considerably higher during mid-late proliferative and early-mid secretory, than early proliferative and reduced at late secretory phases of the menstrual cycle and postmenopausal period. The results demonstrate for the first time that human fallopian tube expresses GM-CSF and its alpha and beta receptors mRNA and contains the immunoreactive gene product for GM-CSF, and may be potentially regulated by ovarian steroids. The results imply the importance of GM-CSF in a variety of tubal functions and possibly the early embryonic development.

DNA Restriction Enzymes↗
PubMed1994

Human fallopian tube expresses transforming growth factor (TGF beta) isoforms, TGF beta type I-III receptor messenger ribonucleic acid and protein, and contains [125I]TGF beta-binding sites.

Reverse transcription-polymerase chain reaction analysis of total ribonucleic acid (RNA) from human fallopian tubes revealed that transforming growth factor-beta 1 (TGF beta 1), TGF beta 2, and TGF beta 3 as well as TGF beta type I-III messenger RNA (mRNA) are expressed in this tissue. In situ hybridization and immunohistochemical observations using TGF beta isoform-specific [35S]40-mer oligonucleotide probes and polyclonal antibodies indicate that all the tubal cell types express TGF beta isoforms and TGF beta type II receptor mRNA and protein. The tubal epithelial cells appeared to express more TGF beta 1 mRNA and TGF beta 1-3 proteins than other cell types, whereas TGF beta 2 and TGF beta 3 mRNA appeared to be equally expressed in the epithelial and other tubal cell types. In the epithelial lining, both ciliated and nonciliated cells in the ampullary and isthmus regions appeared to express mRNA and protein for TGF beta s and TGF beta type II receptor at a similar level. The intensity of immunostaining of TGF beta s in tubal epithelial cells was lower during the early proliferative and late secretory than the mid- to late proliferative and early to midsecretory phases of the menstrual cycle and reduced during the postmenopausal period. However, the intensity of immunoreactive TGF beta type II receptor in these cells did not vary during the cycle as much as that seen with TGF beta s. Quantitative autoradiography of [125I]TGF beta 1 indicates that fallopian tubes contain specific binding sites for TGF beta 1. Net grain density per 100 microns 2, calculated for different cell types, indicates that the epithelial cells had a significantly higher grain density than other tubal cell types (P < 0.05), with similar densities in the late proliferative and early secretory phases of the cycle. These results provide the first evidence that human fallopian tubes express mRNA and protein and contain specific binding sites for TGF beta system, suggesting an autocrine/paracrine role for TGF beta in a variety of tubal functions.

Autoradiography↗
PubMed1994

Localization of transforming growth factor beta isoforms TGF-beta 1, TGF-beta 2, and TGF-beta 3 in surgically induced pelvic adhesions in the rat.

OBJECTIVE: To investigate the presence and cellular distribution of transforming growth factor (TGF)-beta s in surgically induced pelvic fibrous adhesions in rat uterine horns subjected to burn, crush, and debridement injury. METHODS: Thirty injured and 20 uninjured rats were treated postoperatively with intraperitoneal administration of either 2 micrograms/mL of recombinant human TGF-beta, 10 micrograms/mL TGF-beta neutralizing antibody, or phosphate-buffered saline + 500 micrograms rat serum albumin for 5 consecutive days. The intact (uninjured) and fibrous tissues were analyzed immunohistochemically for the presence of TGF-beta s using polyclonal antibodies to TGF-beta s 1-3. RESULTS: The intact peritoneum immunostained with a lower intensity than fibrous adhesive tissues for TGF-beta 1, TGF-beta 2, and TGF-beta 3. The immunoreactive TGF-beta s were present in fibroblasts, inflammatory cells infiltrated into the fibrous adhesion, and endothelial and smooth-muscle cells of the arterioles. In the uterine tissue at the site of injury, the following immunostained for TGF-beta s: uterine serosal tissue, myometrial smooth-muscle cells, endometrial luminal and glandular epithelial cells, and inflammatory cells. However, endometrial stromal cells did not immunostain for TGF-beta s. There were no substantial differences in immunostaining intensities of fibrous adhesive tissues in the TGF-beta group, neutralizing TGF-beta antibody group, and the controls. CONCLUSION: The data suggest that TGF-beta s may play a role in the formation and maintenance of fibrous adhesions following intraperitoneal injury.

Animals↗
PubMed1994

Localization of transforming growth factor beta isoforms TGF-beta 1, TGF-beta 2, and TGF-beta 3 in surgically induced endometriosis in the rat.

OBJECTIVE: To elucidate the presence and cellular distribution of transforming growth factor beta (TGF-beta) in surgically induced endometriosis in the rat. METHODS: Endometriosis was induced by implanting pieces of uterine fragments in the mesenteric region adjacent to a blood vessel for a period of 4-6 weeks. The endometrial implants were removed and processed for immunohistochemical localization using isoform-specific polyclonal antibodies to TGF-beta 1, TGF-beta 2, and TGF-beta 3. RESULTS: All the cell types in the endometrial implants with the exception of stromal cells immunostained for TGF-beta 1 and TGF-beta 3, but not TGF-beta 2. The inflammatory cells that were infiltrated among endometriotic stromal cells and implant-associated cysts contained the highest immunostaining intensity for TGF-beta s 1-3, followed by luminal and glandular epithelial cells, fibroblasts of the fibrous adhesions, and endothelial and smooth-muscle cells of arterioles. The immunostaining intensity of TGF-beta 1 was substantially higher than that of TGF-beta 3 and TGF-beta 2, and intensity was similar to the endometrial tissue from cycling rats in diestrus II for TGF-beta 1 and estrus for TGF-beta 2 and TGF-beta 3. In the cycling rats, the order of immunostaining intensity in the endometrium was TGF-beta 1, TGF-beta 3, and TGF-beta 2, respectively, with a higher intensity in diestrus II and proestrus than in diestrus I and estrus. CONCLUSION: The results indicate that endometrial implants in surgically induced endometriosis contain immunoreactive TGF-beta s, which may imply a possible paracrine/autocrine role for the action of TGF-beta in the maintenance of viable endometriotic tissue and the development of fibrous adhesions associated with the implants.

Animals↗
PubMed1993

Characterization of antinuclear autoantibodies present in the serum from nonobese diabetic (NOD) mice.

The nonobese diabetic (NOD) mouse develops insulin-dependent type 1 diabetes in response to autoantibodies and T-cell attack directed against pancreatic islet cell antigens. Sera obtained from nondiabetic and diabetic female mice demonstrated a 1.4-fold increase in IgG levels when compared to BALB/c control animals. Nondiabetic and diabetic male mice had a 2.1- and 3-fold increase, respectively, in serum IgG levels over that of control mice. Seven of 11 non-diabetic and 7/10 diabetic sera from female NOD mice contained antibody to cytoplasmic or nuclear components of HEp-2 cells. Cytoplasmic staining revealed reaction against cytoskeletal and midbody structures. Punctate nuclear staining patterns with HEp-2 cells showed antibody reaction to the centriole, mitotic chromosomes, and nuclear rim. On the other hand, sera from BALB/c mice were negative for antibody staining of HEp-2 cells. Confirmation of the autoantibody nature of the NOD sera was obtained by antibody staining of nuclear structures from the mouse 3T3 fibroblast cell line, and by staining of salivary gland tissue sections. The nuclear and cytoplasmic staining patterns of diabetic NOD sera were reminiscent of the autoantibody staining patterns observed in Sjögren's syndrome and other inflammatory autoimmune connective tissue diseases.

Animals↗
PubMed1993

Cellular distribution of epidermal growth factor, transforming growth factor-alpha, and epidermal growth factor receptor in fascia and peritoneum during healing in the rat: an autoradiographic and immunohistochemical study.

The presence and cellular distribution of epidermal growth factor (EGF), TGF-alpha, and EGF-R were determined in the rat fascial and peritoneal tissue during healing of an incisional injury by means of immunohistochemistry and autoradiographic techniques. The immunostaining intensity for EGF in the regenerating wound area was substantially higher during the first 14 days, then decreased to near prewound levels during 14 to 35 days after surgery. Within the wound area, the most intense immunostaining occurred with inflammatory cells, followed by fascial striated muscle and arterioles, whereas fibroblasts in the regenerating area contained very low immunostaining intensity. The immunostaining pattern for TGF-alpha with the use of three separate polyclonal antibodies that were directed against the amino and carboxy termini of TGF-alpha precursor and a fragment of the mature 50-amino-acid form of TGF-alpha was similar to that seen with EGF and persisted until 28 days after injury. However, fibroblasts in the regenerating area immunostained intensely for TGF-alpha but not for EGF. Quantitative autoradiography of iodine 125-labeled EGF binding and immunohistochemical studies of the EGF-R with monoclonal antibodies that were directed against the extracellular binding domain of EGF-R demonstrated the presence of specific EGF-R in regenerating fascial and peritoneal tissue. Net grain density (100 microm(2)), representing specific binding of (125)I-EGF, was calculated for different cell types in the wound. The grain density over fascial striated muscle, migratory fibroblasts and peritoneal fibroblasts increased by two and one half, three, and four times, respectively, at 7 days and decreased to the values in adjacent unwounded tissue by 21 days after injury (p < 0.05). Immunostaining for the EGF-R generated similar patterns, which persisted for 14 days after injury. The grain density and immunostaining for EGF-R over the arterioles in the wound did not change during the course of healing and was similar to that of the uninjured regions. In summary, these observations indicate that the local levels of EGF, TGF-alpha, and EGF-R increase during the early phases of healing in fascial and peritoneal injury, which suggests a role for these growth factors in the normal mechanism of fascial/peritoneal wound healing and fibrous adhesion formation.

Journal Article↗
PubMed1993

TGF-alpha protein and receptor localization in laryngotracheal tissue.

Both normal cell turnover and healing of laryngeal and tracheal injuries involve cell migration and mitosis. The proteins that regulate normal cell turnover and wound healing in the larynx and trachea have not been established. It is possible that peptide growth factors, such as transforming growth factor-alpha (TGF alpha) acting through its receptor (EGF/TGF alpha-R), participate in the regulation of these processes. To investigate this hypothesis, we analyzed laryngotracheal cells for TGF alpha protein and receptor in normal and postwounding conditions. TGF alpha protein was detected by immunohistochemical analysis in normal ferret laryngeal and tracheal mucosa. Specific binding to the EGF/TGF alpha receptor in membrane homogenates of ferret larynx and trachea reached saturation after 60 minutes at 37 degrees C, and was effectively displaced by unlabeled epidermal growth factor (EGF) or TGF alpha, but not by unlabeled insulin, angiotensin II, or basic fibroblast growth factor. Scatchard analysis of the specific binding indicated the presence of high-affinity (Kd = 117 pmol) and low-affinity (Kd = 40 nmol) binding sites. The maximum number of available binding sites was 73 fmol/mg protein. Localization of the EGF/TGF alpha receptor by autoradiographic analysis of 125I-EGF binding to sections of normal ferret larynx and trachea revealed EGF/TGF alpha receptors throughout the epithelium, with the highest grain density in the basal layers. Quantitative analysis of autoradiographic grain density between normal, intubated, and extubated animals revealed no significant differences. The presence of TGF alpha protein and its receptor in normal and wounded larynx and trachea supports the hypothesis that these proteins are involved in regulating physiologic responses of laryngotracheal cells.

Angiotensin II↗
PubMed1992

Effect of transforming growth factor beta on postoperative adhesion formation and intact peritoneum.

Transforming growth factor beta (TGF beta) is an extremely potent chemoattractant for macrophages, mononuclear leukocytes, and fibroblasts. It also acts as a potent stimulant for collagen and fibronectin synthesis and inhibits epithelial cell growth. TGF beta plays an important role in healing many types of wounds, but its role in peritoneal adhesion formation is not known. These studies were performed to determine if TGF beta could affect postoperative wound healing in a rat model. In the first experiment, 20 rats were divided into two groups and received either 2 micrograms TGF beta or control diluent IP daily for 5 days after surgical injury to the uterine horns. The severity of the adhesions were graded 2 weeks postoperatively using a score of 0-3. The TGF beta group showed a higher adhesion score at 2 weeks compared to control, 2.9 +/- 0.34 and 1.6 +/- 0.61, respectively (P less than 0.001). On H&E stained sections of the adhesions, there was an increase in the number of both inflammatory cells and fibroblasts in the TGF beta-treated animals. A comparison trial of bone-derived TGF beta (a gift from Collagen Corporation, Palo Alto, CA) versus recombinant TGF beta (a gift from Oncogen, Seattle, WA) versus control using the same protocol as above showed that both sources of TGF beta were more effective in promoting postoperative adhesions when compared to controls, and there was no difference between TGF beta groups, 3.0 +/- 0 for both TGF beta groups, and 2.2 +/- 0.91 for control (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Effects of growth factors on corneal wound healing.

Healing of ocular surface wounds is a complex process involving migration, mitosis, and differentiation of epithelial and stromal cells. Endogenously produced peptide growth factors such as epidermal growth factor (EGF), transforming growth factor alpha (TGF-alpha), or transforming growth factor beta (TGF-beta) may play key roles in the natural wound healing process. Lacrimal gland cells were reported to synthesize and secrete EGF into tear fluid where it may enhance healing of corneal epithelial and stromal injuries by an exocrine pathway. EGF stimulated DNA synthesis of epithelial cells and stromal fibroblasts in culture, stimulated synthesis of fibronectin by epithelial cells and was chemotactic for human epithelial and stromal cells. Human corneal epithelial cells also synthesized TGF-alpha which may influence epithelial cells by an autocrine pathway. TGF-beta, which is a potent inducer of lysyl oxidase mRNA levels in cultures of human scleral fibroblasts, may be the factor most responsible for inducing synthesis of corneal extracellular matrix components after an injury. Treatment of epithelial injuries ocular surface wounds with exogenous peptide growth factors also accelerated healing in rabbits and primates. Treatment of severe ocular surface injuries caused by alkali with a combination of EGF, fibronectin, a synthetic collagenase inhibitor, and Aprotinin significantly blocked ulceration and enhanced epithelial regeneration. Clinical trials of topical treatment of EGF for ocular surface wounds suggest that peptide growth factors may be a valuable adjuvant for treatment of ocular surface wounds.

Animals↗
PubMed1992

Presence of epidermal growth factor, platelet-derived growth factor, and their receptors in human myometrial tissue and smooth muscle cells: their action in smooth muscle cells in vitro.

Immunohistochemical observations indicate that human myometrial smooth muscle cells express epidermal growth factor (EGF) and platelet-derived growth factor (PDGF)-AB and contain EGF and PDGF-beta receptors with no variation in intensity with phases of the menstrual cycle. Furthermore, immunofluorescent microscopic studies revealed that primary myometrial smooth muscle cell cultures also express EGF, PDGF-AB, and contain EGF and PDGF-beta, but not alpha-receptor. Incubation of subconfluent smooth muscle cells in serum-free medium leads to quiescence within 48 h as demonstrated by 3H-thymidine incorporation and labeling index. Exposure of quiescent cells to 10% fetal bovine serum stimulates resumption of DNA synthesis and proliferation in a time-dependent manner with a doubling time of 41.6 h. EGF (1.5-50 ng/ml) and PDGF-AB (1-10 ng/ml) in a dose- and time-dependent manner significantly stimulated 3H-thymidine incorporation by quiescent myometrial smooth muscle cells (P less than 0.05). Combinations of EGF (15 ng/ml) and PDGF-AB (10 ng/ml) significantly increased 3H-thymidine incorporation induced by either growth factor alone (P less than 0.05). PDGF-BB at 10 ng/ml also stimulated 3H-thymidine incorporation and its effect was similar to that induced by PDGF-AB at the same concentration. 17 beta-Estradiol (E2) at 1 microM inhibited 3H-thymidine incorporation by the smooth muscle cells (P less than 0.05). E2 also reduced the stimulatory effect of EGF (15 ng/ml) and PDGF (3 ng/ml). Progesterone at 1 microM either alone or in combination with E2 did not have any effect on 3H-thymidine incorporation or alter the mitogenic action of EGF and PDGF. The effect of EGF and PDGF on cell growth and 3H-thymidine incorporation by myometrial smooth muscle cells was independent of phases of the menstrual cycle. In summary, the results of present studies indicate that human myometrial tissue and myometrial smooth muscle cells in primary culture locally produce EGF and PDGF-AB and contain EGF and PDGF-beta, but not alpha-receptors. Moreover, the myometrial smooth muscle cells in culture respond to the mitogenic action of EGF and PDGF.

Autoradiography↗
PubMed1992

Presence of transforming growth factor-beta and their selective cellular localization in human ovarian tissue of various reproductive stages.

Immunohistochemical studies were performed using specific polyclonal antibodies to transforming growth factor (TGF)-beta 1 and TGF-beta 2 to determine their presence and cellular localization in human ovarian tissues of various reproductive states. In the small ovarian follicles, the immunostaining for TGF-beta 1 was present in oocytes, follicle cells, and granulosa and theca cell layers. The level of immunostaining associated with granulosa and theca cell layers intensified as the size of the follicles increased. In the luteal tissue, both the small and large luteal cells immunostained for TGF-beta 1 and their intensities were similar to theca and granulosa cell layers, respectively. The patterns of immunostaining were similar in early (days 14-19), mid (days 22-25), and late (days 26-29) luteal phases; however, the intensity was highest at mid and decreased at late luteal phase. Corpus albicans showed a very weak immunostaining for TGF-beta 1, whereas ectopic pregnancy small luteal cells immunostained relatively intensely. The ovarian stromal, luteal tissue fibroblasts, and arterioles endothelial and smooth muscle cells were also immunostained for TGF-beta 1. The immunostaining of the ovarian tissues for TGF-beta 2 indicated that the theca cell layers were the exclusive cells in the follicles with intense immunostaining, which increased in the larger follicles. A low immunostaining was also observed in granulosa cell of the large follicles. In the luteal tissues, only small luteal cells showed intense immunostaining for TGF-beta 2, which was similar in intensity to that in the theca cells; however, the large luteal cells showed a low level of immunostaining at midluteal phase. The small luteal cells in corpus albicans and ectopic pregnancy luteal tissues retained their immunostaining for TGF-beta 2, but with lower intensity. Endothelial and smooth muscle cells of arterioles also immunostained for TGF-beta 2, but not ovarian stromal cells. Atretic follicles showed very low or no detectable immunostaining for TGF-beta 1 or TGF-beta 2. The results of present studies show that human ovarian tissue at all the reproductive states locally produces TGF-beta 1 and TGF-beta 2, and although TGF-beta 1 is present in most major ovarian cell types, TGF-beta 2 is only produced by theca cells in the follicles and small luteal cells in luteal tissues.

Endothelium, Vascular↗
PubMed1992

Platelet-derived growth factor (PDGF), epidermal growth factor (EGF), and EGF and PDGF beta-receptors in human endometrial tissue: localization and in vitro action.

Human endometrial tissue and primary stromal cell culture contain immunoreactive epidermal growth factor (EGF), platelet-derived growth factor (PDGF)-AB as well as EGF and PDGF-beta receptors. The immunostaining for EGF, EGF receptor, and PDGF beta-receptor were associated with endometrial luminal and glandular epithelial and stromal cells, whereas only the stromal cells contain immunoreactive PDGF-AB. The immunostaining intensity of EGF, EGF receptor, and PDGF-AB was similar in both phases of the menstrual cycle, whereas, PDGF-beta receptor immunostaining was highest in proliferative phase and considerably reduced, particularly in luminal and glandular epithelial cells in the secretory phase. In addition primary stromal cell cultures express EGF, PDGF-AB, and contain EGF and PDGF-beta receptors, and very low levels of PDGF-alpha receptor. 3H-Thymidine incorporation indicate that after 48 h of incubation in serum-free medium approximately 75-80% of stromal cells are quiescent. Incubation of quiescent stromal cells with 10% fetal bovine serum stimulate 3H-thymidine incorporation in a time-dependent manner reaching maximal after 30-48 h, with a doubling time of 38.2 h. EGF (1.5-15 ng/ml) stimulates 3H-thymidine incorporation by quiescent stromal cells (P less than 0.001). This effect was significantly reduced at concentrations above 15 ng/ml (P less than 0.005). PDGF-AB (3-10 ng/ml) and PDGF-BB (0.5-10 ng/ml) also stimulate 3H-thymidine incorporation in quiescent stromal cells compared to controls (P less than 0.005). The action of EGF (15 ng/ml) and PDGF-AB (10 ng/ml) was time dependent, reaching maximal after 36 and 48 h of incubation (P less than 0.002). Addition of PDGF-AB (10 ng/ml) to EGF (15 ng/ml) significantly enhanced the action of EGF or PDGF-AB used individually (P less than 0.001). 17 beta-estradiol or progesterone at 1 microM did not stimulate 3H-thymidine incorporation, although they were stimulatory in combination (P less than 0.001), they did not alter the action of EGF or PDGF when added in combination. These observations provide further evidence that human endometrial tissue contains specific immunoreactive EGF receptors. It also demonstrates the presence of immunoreactive EGF, PDGF-AB, and PDGF-beta receptors in endometrial tissue as well as stromal cells in primary culture. Both EGF and PDGF are mitogenic for endometrial stromal cells, suggesting an autocrine/paracrine role in modulation of endometrial cell growth and differentiation.

Cell Division↗
PubMed1992

Immunocytochemical localization of transforming growth factors (TGFs) TGF-alpha and TGF-beta in human ovarian tissues.

Light microscopic immunocytochemical technique was utilized in order to elucidate the presence and cellular distribution of transforming growth factors alpha and beta (TGF-alpha and TGF-beta) in human ovarian tissues in different reproductive states using polyclonal antibodies to TGF-alpha and TGF-beta. The results indicated that the ovarian tissue immunostained for both TGF-alpha and TGF-beta. The immunostaining for TGF-alpha was associated with oocytes in the primary follicles, granulosa and theca cell layers, as well as small and large luteal cells. The granulosa cell layers in the small follicles were immunostained for TGF-alpha, but there was very little staining association to the theca cell layers. However, the immunostaining intensity increased in both granulosa and theca cell layers as the size of the follicles increased. The ovarian stroma cells always showed moderate immunostaining. In luteal tissue, both small and large luteal cells immunostained for TGF-alpha and the intensity was similar in both cell types. The immunostaining intensity was similar in both early and midluteal phases and was less than that seen in the granulosa-theca cell layers of the large follicles, and decreased in the late luteal phase. Both corpora albicans and ectopic pregnancy corpora lutea showed a weak immunostaining. Immunostaining of ovarian tissues for TGF-beta indicated that the oocytes of the small preantral follicles stained faintly in the cytoplasm; however, they stained strongly around the nuclear periphery. In small, medium, and large follicles granulosa and theca cell layers immunostained with similar intensity for TGF-beta and its intensity increased with follicular size. The ovarian stroma cells also immunostained for TGF-beta, but with a moderate to low intensity compared with other regions. In luteal tissue, both small and large luteal cells immunostained for TGF-beta and its intensity was similar in early and midluteal phases and reduced during the late luteal phase. This immunostaining was reduced as compared to the granulosa-theca cell layers of the follicles. Corpora albicans and ectopic pregnancy corpora lutea also immunostained for TGF-beta; however, the immunostaining intensity was lower than that seen in luteal tissues of early, mid, or late luteal phases. There was strong immunostaining of the luteal fibroblasts and, interestingly, in small and medium size arterioles; endothelial and smooth muscle cells also immunostained strongly for TGF-beta, whereas the large arterioles showed very little or no immunostaining.(ABSTRACT TRUNCATED AT 400 WORDS)

Epidermal Growth Factor↗
PubMed1992

Treatment of alkali-injured rabbit corneas with a synthetic inhibitor of matrix metalloproteinases.

Healing of corneal alkali injuries remains a severe clinical challenge. The authors evaluated the effect of a new synthetic inhibitor of matrix metalloproteinases (GM6001 or N-[2(R)-2-(hydroxamido carbonylmethyl)-4-methylpentanoyl]-L-tryptophane methylamide) on preventing ulceration of rabbit corneas after alkali injury. Topical treatment of corneas with severe alkali injuries with 400 micrograms/ml or 40 micrograms/ml GM6001 alone prevented ulceration for 28 days, although 8 of 10 corneas treated with vehicle perforated. Corneas treated with 4 micrograms/ml GM6001 had midstromal depth ulcers. Corneas treated with 400 micrograms/ml of GM6001 contained very few inflammatory cells and had significantly reduced vessel ingrowth compared with vehicle-treated corneas. Epithelial regeneration after moderate alkali injuries also was investigated. Persistent epithelial defects developed 4 days after moderate alkali injury in rabbit corneas treated with vehicle and progressively increased to an average of 20% of the original 6 mm diameter wound by 27 days after moderate alkali injury. By contrast, epithelial regeneration was complete and persisted for 21 days for corneas treated with a formulation containing GM6001 (400 micrograms/ml), epidermal growth factor (10 micrograms/ml), fibronectin (500 micrograms/ml), and aprotinin (400 micrograms/ml). Sporadic punctate staining developed in 20% of the corneas treated with the combination of agents between days 21-28 after moderate alkali injury. These results demonstrate that topical application of GM6001 prevented corneal ulceration after severe alkali injury and that a combination containing GM6001, epidermal growth factor, fibronectin, and aprotinin promoted stable regeneration of corneal epithelium after moderate alkali injury.

Alkalies↗
PubMed1992

Detection of transforming growth factor-alpha messenger RNA and protein in human corneal epithelial cells.

Human corneal epithelial cells are normally shed from the apical surface and replaced primarily by mitosis of basal cells. Growth factors may regulate this process, but the sources for the growth factors have not been fully established. One potential source for growth factors is tear fluid, and epidermal growth factor (EGF) has been detected in the lacrimal gland and in tears. However, the hydrophilic structure and size of growth factors such as EGF may limit penetration to basal layers of intact epithelium. It is possible that turnover of basal human corneal epithelial cells might be regulated by growth factors acting by an autocrine mechanism. To determine if human corneal epithelial cells synthesize a potential autocrine growth factor, the authors analyzed human corneal epithelial cells for transforming growth factor-alpha (TGF-alpha) messenger RNA and protein, a growth factor that is structurally related to EGF and binds to the EGF receptor. Radioimmunoassay of human corneal epithelial cell cultures detected substantial levels of immunoreactive TGF-alpha (3 ng/10(6) cells). Immunohistochemical staining of human corneas also revealed the presence of immunoreactive TGF-alpha in the corneal epithelium. Northern hybridization with a 32P-labeled complementary DNA probe for TGF-alpha generated a single intense band at 4.4 kilobases, indicating the presence of TGF-alpha messenger RNA in cultured human corneal epithelial cells. These results support the hypothesis that normal turnover of corneal epithelium is controlled by the autocrine production of growth factors, such as TGF-alpha. Growth factors present in tears may function primarily as exocrine factors to stimulate healing of epithelial injuries after the epithelial barrier has been damaged.

Autoradiography↗
PubMed1991

Nuclear volume and chromatin conformation of small and large bovine luteal cells: effect of gonadotropins and prostaglandins and dependence on luteal phase.

Change in nuclear volume and chromatin conformation are generally considered to reflect altered gene expression in eukaryotic cells. The present studies were undertaken to investigate whether these nuclear parameters of luteal cells can be altered by hormone treatment in vitro or change during the estrous cycle. The nuclear volume of small luteal cells was significantly lower than that of large luteal cells during the cycle and pregnancy. The nuclear volumes of small and large luteal cells from pregnancy did not change during incubation without any hormone or with 10 nM prostaglandin (PG)F 2 alpha. However, incubation with 1 nM human chorionic gonadotropin (hCG) or 10 nM PGE1 resulted in a significant increase of nuclear volume of small luteal cells by 4 h and that of large luteal cells by 6 h. Small luteal cells were more responsive to hCG than large luteal cells. The nuclear volumes of small and large luteal cells also significantly increased from early to mid luteal phase with no further change in late luteal phase. hCG and PGE1, as well as PGF2 alpha, treatment resulted in a change of chromatin conformation of small and large luteal cells. Dibutyryl cyclic AMP (10 mM) mimicked the hormones by increasing nuclear volumes and changing the chromatin conformation of small and large luteal cells. Chromatin conformation of small and large luteal cells also changed from early to mid luteal phase and mid to late luteal phase. In conclusion, in vitro, hCG and PGs can regulate nuclear volume and/or chromatin conformation of small as well as large bovine luteal cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Alprostadil↗