Immunohistochemical localization of epidermal growth factor receptor (EGF-r) and transforming growth factor alpha (TGF-alpha) in developing human ovarian follicles

In this study, we aimed to detect the distribution of epidermal growth factor receptor (EGF-r) and transforming growth factor alpha in ovarian follicles at different stages. Indirect immunohistochemical methods and EGF-r polyclonal and TGF-alpha monoclonal antibodies were used; tissues were examined with light microscope. While dense collection of both growth factors were observed in primordial follicles, there was a strong reaction especially for EGF-r in follicles. Strong reactivity for EGF-r and moderate reactivity for TGF-alpha were observed in the nearby connective tissue. In examinations of primary follicles for EGF-r presence only, dye uptake was moderate in oocytes and dense in apical and basal cytoplasm of follicle cells. Reactivity was moderate in the nearby connective tissue. In the corpus luteum, there was weak reaction for both growth factors. But in stromal cells, reaction was strong. In degenerated follicle cells and in stroma of atretic follicles, reaction was positive for both growth factors; but EGF-r reactivity was more obvious. While strong staining was observed for both factors especially in granulosa cells surrounding the oocyte in Graafian follicle, moderate TGF-alpha reactivity was determined in oocyte cytoplasm. In conclusion, it is possible that EGF-r and TGF-alpha have ortocrine and paracrine effects on development and regression of human ovarian follicles.     

Patterns of nerve growth factor (NGF), proNGF, and p75 NGF receptor expression in the rat incisor: comparison with expression in the molar

Abstract. Nerve growth factor (NGF), a target-derived neurotrophic substance, may have broader biological functions in various types of nons-neuronal differentiating cells. The effects of NGF are dependent on initial binding of NGF to specific cell-surface receptors (p75^NGFR and p140^prototrk) on responsive cells. The continously growing rat incisor offers an excellent model demonstrating defined territories of differentiation of specific cell populations. We used immunohistochemistry to determine sites of NGF. proNGF and p75^NGFR accumulation in the rat incisor, whereas NGF mRNA expression was visualized by in situ hybridization in the developing rat molar and incisor. Strictly similar patterns of NGF mRNA, proNGF and NGF expression were observed in differentiating cells responsible for the production of the main structural matrices of the tooth. Thus, proNGF-like and NGF-like immunoreactivity, as well as the NGF mRNA signal were observed in preameloblasts and young ameloblasts of the dental epithelium and in polarizing odontoblasts of the dental mesenchyme. In contrast, the distribution of p75^NGFR was correlated with differentiation events only in dental mesenchyme: polarizing odontoblasts expressed p75^NGFR whereas the molecule was absent in functional odontoblasts. In dental epithelium, the restricted expression of p75^NGFR in ameloblast precursor cells was correlated with proliferative phenomena. The patterns of proNGF, NGF and p75^NGFR expression in epithelium and mesenchyme implicate both an autocrine and paracrine mode of action of the NGF molecule in dental tissues. The findings reported here are important for understanding NGF action in specific dental cell populations and suggest that this molecule is involved in the cascade of events that directs tooth development.     

Expression and localization of nerve growth factor (NGF) in the testis of alpaca (llama pacos)

During alpaca testis development and spermatogenesis, nerve growth factor (NGF) may play an important role. The main aim of this study was to determine the expression and localization of NGF in the alpaca testis, and to discuss the important role of NGF in alpaca reproductive characteristics. Immunohistochemical staining technique and real-time PCR were used. The expression of NGF in the same cells one-month old (newborn) alpacas 12-month, and 24-month old alpacas showed significant differences (p < 0.05); 12- and 24-month old alpacas showed no significant differences (p > 0.05); NGF at different cell stages showed no significant differences (p > 0.05). It suggests that NGF may be involved in the regulation of spermatogenesis, which provides direct evidence for NGF action in the alpaca testis during postnatal development and spermatogenesis.     

The synthesis of nerve growth factor (NGF) in developing skin is independent of innervation

The arrival of sensory fibers in developing mouse skin has been demonstrated to coincide precisely with the initiation of nerve growth factor (NGF) synthesis in the skin (Davies et al., 1987). This temporal correlation suggested that the arrival of sensory fibers might initiate NGF synthesis in their target tissues. Here we have eliminated the sensory and motor neurons projecting to the chick leg by the removal of the neural primordia in 3-day-old embryos. The levels of mRNA NGF of intact and denervated leg skin were identical, indicating that the developmental regulation of NGF synthesis in the skin of chick embryos is independent of its innervation.     

Immunohistochemical localization of low-affinity nerve growth factor receptor in the enteric nervous system of adult rats

The localization of low-affinity nerve growth factor receptor in the enteric nervous system of adult rats has been studied by immunohistochemistry using a monoclonal antibody (clone 192) against the rat receptor. Cryostat and whole-mount sections were stained. By light and confocal microscopy, positive staining in neural structures was found in every part of the gut. In the ganglionic plexus, dense staining was detected in the neuropil surrounding neuronal cell bodies that were themselves devoid of immunoreactivity. Immunoelectron microscopy revealed deposition of reaction products on the outer plasma membranes of both perikarya and processes of neuronal as well as glial cells. Such a selective localization of the receptor in the plasma membrane, but not the cytoplasm, suggests that the mechanisms of receptor-ligand interaction in the gut may differ from those in the brain, where internalization of the receptor is observed in cholinergic cells. The present study provides the morphological basis for future studies designed to elucidate the functional significance of this enteric nervous system receptor. Since it is found in both neuronal and glial cells, it is probably under the influence of a number of trophic factors, including nerve growth factor This revised version was published online in November 2006 with corrections to the Cover Date.     

A quantitative study of the developmental expression of nerve growth factor (NGF) receptor in rats

The developmental expression of nerve growth factor (NGF) receptor was quantitated in either homogenates or plasma membrane-enriched preparations from whole rat embryos or from isolated tissues. The assay involved crosslinking 125I-NGF to receptors followed by immunoprecipitation with a monoclonal antibody to rat NGF receptor. In some cases, the pellet was resuspended and subjected to a sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) autoradiographic analysis. The NGF receptor was found in whole embryo homogenates as early as embryonic Day 10 (E10) (earliest age examined). The NGF receptor content in whole embryos per milligram protein increased about 3-fold from E11 to E18 and decreased slightly at E20. SDS-PAGE autoradiography showed that the molecular weights of 125I-NGF-bound receptors did not vary with age. The NGF receptor content in sciatic nerve homogenates decreased 23-fold from newborn to adulthood. The change of NGF receptor level in hindleg muscle had a profile similar to that seen in sciatic nerve. The NGF receptor content in superior cervical ganglion (SCG) or dorsal root ganglion (DRG) homogenate preparations was expressed in two ways. On a per milligram protein basis, in SCG, the receptor density was decreased slightly from E20 to adulthood; in DRG, it was relatively constant from E15 through postnatal Day 0 (PND-0) and then dropped 6.7-fold in adults. On a per ganglion basis, in SCG, it increased 4.4-fold from E20 to adult; in DRG, it increased 9-fold from E15 to PND-0 and then stayed constant through adulthood. In brain membrane preparations, the NGF receptor level decreased 11-fold from E15 to adulthood. In spinal cord membrane preparations, it decreased 7-fold from E18 to adulthood. Levels of receptor in cord were always greater than in brain. These data suggest that alterations in the NGF receptor density may have a role in changes in tissue responsiveness to NGF during development.     

Immunohistochemical localization of epidermal growth factor in rat and man

Epidermal growth factor (EGF) is a peptide which stimulates cell mitotic activity and differentiation, has a cytoprotective effect on the gastroduodenal mucosa, and inhibits gastric acid secretion. The immunohistochemical localization of EGF in the Brunner's glands and the submandibular glands is well documented. The localization of EGF in other tissues is still unclarified. In the present study, the immunohistochemical localization of EGF in tissues from rat, man and a 20 week human fetus were investigated. In man and rat, immunoreaction was found in the submandibular glands, the serous glands of the nasal cavity, Brunner's glands of the duodenum, the Paneth cells of the small intestine, and the tubular cells of the kidney. In the fetus EGF was found in the kidney and in the intestinal Paneth cells. Antisera raised against rat submandibular EGF did not recognize EGF in human tissues, whereas antisera against human urinary EGF worked in rat as well as man. EGF was found only in cells with an exocrine function.     

Immunohistochemical localization of epidermal growth factor in rat and man

Summary Epidermal growth factor (EGF) is a peptide which stimulates cell mitotic activity and differentiation, has a cytoprotective effect on the gastroduodenal mucosa, and inhibits gastric acid secretion.The immunohistochemical localization of EGF in the Brunner's glands and the submandibular glands is well documented. The localization of EGF in other tissues is still unclarified.In the present study, the immunohistochemical localization of EGF in tissues from rat, man and a 20 week human fetus were investigated. In man and rat, immunoreaction was found in the submandibular glands, the serous glands of the nasal cavity, Brunner's glands of the duodenum, the Paneth cells of the small intestine, and the tubular cells of the kidney. In the fetus EGF was found in the kidney and in the intestinal Paneth cells.Antisera raised against rat submandibular EGF did not recognize EGF in human tissues, whereas antisera against human urinary EGF worked in rat as well as man. EGF was found only in cells with an exocrine function.     

Evidence for the presence of nerve growth factor (NGF) and NGF receptors in human testis

Summary The co-localization of arginine vasopressin-and enkephalin-like immunoreactivities in nerve cells of the rat paraventricular hypothalamic nucleus and adjacent areas was investigated by the simultaneous application of immuno--galactosidase staining and the peroxidase-antiperoxidase method to sections. Arginine vasopressin-like immunoreactive cells were stained blue with immuno--galactosidase staining and enkephalin-like immunoreactive cells brown with the peroxidase-antiperoxidase method. Double-labeled cells with overlap of blue and brown immunoreaction products were identified in the anterior, medial, and lateral parvocellular parts of the paraventricular hypothalamic nucleus as well as in the previously indicated posterior magnocellular part. Other regions that contained double-labeled cells were the lateral hypothalamic area, anterior hypothalamic nucleus, area between the lateral hypothalamic area and anterior hypothalamic nucleus, suprachiasmatic nucleus, and bed nucleus of the stria terminalis, medial division, posterolateral part. These findings suggest that nerve cells with both arginine vasopressin- and enkephalin-like immunoreactivities may be more actively involved in neuroendocrine regulation and neural transmission than previously considered. They may provide a morphological basis for an increase in enkephalin-like immunoreactivity within the anterior pituitary in cases of hemorrhagic shock which is presumably accompanied by arginine vasopressin hypersecretion.Abbreviations AH anterior hypothalamic nucleus - ap anterior parvocellular part of the paraventricular hypothalamic nucleus - BSTMPL bed nucleus of the stria terminalis, medial division, posterolateral part - dp dorsal parvocellular part of the paraventricular hypothalamic nucleus - f fornix - LH lateral hypothalamic area - lp lateral paryocellular part of the paraventricular hypothalamic nuclcus - mp medial parvocellular part of the paraventricular hypothalamic nucleus - MPA medial preoptic area - pm posterior magnocellular part of the paraventricular hypothalamic nucleus - pv periventricular part of the paraventricular hypothalamic nucleus - SC suprachiasmatic nucleus - Zi zona incerta     

Immunohistochemical localization of nerve growth factor and epidermal growth factor in guinea pig prostate gland

Prostate glands of adult guinea pigs were stained for nerve growth factor (NGF) and epidermal growth factor (EGF) by immunohistochemical methods. Both NGF and EGF were localized diffusely in the cytoplasm of the glandular epithelial cells, and also in their secretory products. These findings suggest that NGF and EGF are synthesized, stored, and secreted by the glandular epithelial cells of the prostate.     

Immunohistochemical localization of nerve growth factor and epidermal growth factor in guinea pig prostate gland

Summary Prostate glands of adult guinea pigs were stained for nerve growth factor (NGF) and epidermal growth factor (EGF) by immunohistochemical methods. Both NGF and EGF were localized diffusely in the cytoplasm of the glandular epithelial cells, and also in their secretory products. These findings suggest that NGF and EGF are synthesized, stored, and secreted by the glandular epithelial cells of the prostate.     

Immunohistochemical localization of insulin-like growth factor I in the adult rat

Rabbit antisera against native human insulin-like growth factor I (IGF-I; somatomedin C) or a synthetic tetradecapeptide, representing the carboxyterminal amino acids 57-70 of human IGF-I, were used to map immunohistochemically the distribution of IGF-I immunoreactive material in adult rats. Both antisera were specific for IGF-I, as characterized by immunoabsorption, immunoblotting and radioimmunoassay. There was no cross-reactivity to IGF-II, relaxin or pro-insulin; substances having a high degree of structural homology with IGF-I. High IGF-I immunoreactivity was observed in spermatocytes of the testis; in oocytes, granulosa and theca interna cells of the ovary during early stages of follicle development; in some lymphocytes and in reticular cells of lymphoid and hematopoietic organs; in salivary gland duct cells; in the adrenal medulla, the parathyroid gland and the Langerhans' islets. Chondrocytes in the epiphyseal and rib growth plates and at articular surfaces showed strong IGF-I immunoreactivity. Brown but not white fat cells were stained. Nerve cells in the peripheral and autonomic nervous system showed faint to intense IGF-I immunoreactivity. In contrast, neurons and neuroglial cells in the central nervous system were generally negative; motor neurons being an exception. Erythropoietic, thrombocytopoietic and myeloic cells in the bone marrow showed IGF-I immunoreactivity, but only at defined developmental stages. Hepatocytes showed faint IGF-I immunoreactivity, but became more intensely stained after pretreatment with colchicine. The present results suggest that IGF-I is synthetized by cells in several tissues and organs in the adult rat. There was an apparent association between the localization of IGF-I and cell differentiation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Immunohistochemical localization of insulin-like growth factor I in the adult rat

Summary Rabbit antisera against native human insulin-like growth factor I (IGF-I; somatomedin C) or a synthetic tetradeca peptide, representing the carboxyterminal amino acids 57–70 of human IGF-I, were used to map immunohistochemically the distribution of IGF-I immunoreactive material in adult rats. Both antisera were specific for IGF-I, as characterized by immunoabsorption, immunoblotting and radioimmunoassay. There was no cross-reactivity to IGF-II, relaxin or pro-insulin; substances having a high degree of structural homology with IGF-I.High IGF-I immunoreactivity was observed in spermatocytes of the testis; in oocytes, granulosa and theca interna cells of the ovary during early stages of follicle development; in some lymphocytes and in reticular cells of lymphoid and hematopoetic organs; in salivary gland duct cells; in the adrenal medulla, the parathyroid gland and the Langerhans' islets. Chondrocytes in the epiphyseal and rib growth plates and at articular surfaces showed strong IGF-I immunoreactivity. Brown but not white fat cells were stained. Nerve cells in the peripheral and autonomic nervous system showed faint to intense IGF-I immunoreactivity. In contrast, neurons and neuroglial cells in the central nervous system were generally negative; motor neurons being an exception. Erythropoeitic, trombocytopoeitic and myeloic cells in the bone marrow showed IGF-I immunoreactivity, but only at defined developmental stages. Hepatocytes showed faint IGF-I immunoreactivity, but became more intensely stained after pretreatment with colchicine.The present results suggest that IGF-I is synthetized by cells in several tissues and organs in the adult rat. There was an apparent association between the localization of IGF-I and cell differentiation. Certain cells involved in secretory processes also displayed high IGF-I immunoreactivity. The wide distribution of IGF-I indicates that the circulating pool of IGF-I has multiple origins.     

Rita Levi-Montalcini and the discovery of NGF, the first nerve cell growth factor

The nerve growth factor (NGF) is a signaling protein, discovered by Rita Levi-Montalcini in the early 1950's for its effect on growth and differentiation of specific populations of neurons of the peripheral nervous system. Originally identified as neurite outgrowth-stimulating factor, later studies revealed that the purified molecule has a number of target cells in the central nervous system and on nonneuronal cells. Moreover, recent studies showed the potential therapeutic properties of NGF in neuropathies of the central and peripheral nervous system and diseases of the eye and skin. Here I briefly describe the discovery of NGF, the early studies of Rita LeviMontalcini, a pioneer in modern neuroscience, and my scientific and human experience working in her laboratory for over 40 years.     

Immunohistochemical localization of epidermal growth factor receptor (EGF-R) in normal and diseased newborn lung tissues

The distribution of EGF receptors (EGF-R) was examined in normal, hyaline membrane diseased and pneumonic newborn lung tissues by immunohistochemical methods under the light microscope. The PAP technique with polyclonal antibodies was performed to demonstrate the EGF receptor localisation in these tissues. Strong EGF-R reactivity was observed on bronchiolar epithelium and type I and type II alveolar cells in normal newborn lung tissues; whereas, poor reactivity was observed in alveolar macrophages. On the other hand, strong immunoreactivity was detected in type I alveolar cells and alveolar macrophages in hyaline membrane disease, but no reactivity was present in type II alveolar cells. The strongest immunoreactivity was observed in alveolar macrophages of newborn pneumonic lung tissues. In conclusion, the most meaningful form of reactivity was observed in normal newborn lung tissues of airway track and respiration area. This result is related with the maturation of the lungs after birth.     

Spectroscopic and chemical studies of the interaction between nerve growth factor (NGF) and the extracellular domain of the low affinity NGF receptor.

Nerve growth factor (NGF) interacts with a cell surface receptor on responsive neurons to initiate a series of cellular events leading to neuronal survival and/or differentiation. The first step in this process is the binding of NGF to a low affinity and/or a high affinity receptor. In the present report, we have studied the conformation and stability of recombinant receptor extracellular domain (RED) from the human low affinity receptor and the structural basis of its interaction with NGF. Circular dichroism (CD) studies indicate that the RED is primarily random coil in nature with little regular secondary structure. Thermal stability studies have shown that this irregular conformation is a specific structure that can undergo a reversible two-state thermal denaturation with a concomitant fluorescent and CD change. During heating at 100 degrees C for 15 min, the structure of RED is sufficiently unfolded for a reducing agent, dithiothreitol, to inactivate the receptor toward NGF binding and cross-linking. The complex formation between the RED and NGF has been examined by differential CD measurements, and we have shown that a small, reproducible change in conformation occurs in RED or NGF upon interaction. These results are interpreted in terms of the initiation of NGF cell surface binding and possible modes of signal transduction.