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1.
Am J Primatol ; 77(5): 563-78, 2015 May.
Article in English | MEDLINE | ID: mdl-25676781

ABSTRACT

The vaginal microbiome is believed to influence host health by providing protection from pathogens and influencing reproductive outcomes such as fertility and gestational length. In humans, age-associated declines in diversity of the vaginal microbiome occur in puberty and persist into adulthood. Additionally, menstruation has been associated with decreased microbial community stability. Adult female baboons, like other non-human primates (NHPs), have a different and highly diverse vaginal microbiome compared to that of humans, which is most commonly dominated by Lactobacillus spp. We evaluated the influence of age, reproductive cycling status (cycling vs. non-cycling) and menstruation on the vaginal microbiome of 38 wild-caught, captive female olive baboons (Papio anubis) by culture-independent sequencing of the V3-V5 region of the bacterial 16S rRNA gene. All baboons had highly diverse vaginal microbial communities. Adult baboons had significantly lower microbial diversity in comparison to subadult baboons, which was attributable to decreased relative abundance of minor taxa. No significant differences were detected based on cycling state or menstruation. Predictive metagenomic analysis showed uniformity in relative abundance of metabolic pathways regardless of age, cycle stage, or menstruation, indicating conservation of microbial community functions. This study suggests that selection of an optimal vaginal microbial community occurs at puberty. Since decreased diversity occurs in both baboons and humans at puberty, this may reflect a general strategy for selection of adult vaginal microbial communities. Comparative evaluation of vaginal microbial community development and composition may elucidate mechanisms of community formation and function that are conserved across host species or across microbial community types. These findings have implications for host health, evolutionary biology, and microbe-host ecosystems.


Subject(s)
Menstruation/physiology , Microbiota , Papio anubis/microbiology , Vagina/microbiology , Age Factors , Animals , Female , Genome, Bacterial , Metagenome , Ovulation/physiology , Papio anubis/physiology , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics
2.
J Med Primatol ; 43(2): 89-99, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24266633

ABSTRACT

BACKGROUND: Use of a levonorgestrel-releasing intrauterine system (LNG-IUS) in humans may alter vaginal microbial populations and susceptibility to pathogens. This study evaluated the time-dependent effects of an LNG-IUS on the vaginal microbiome of the baboon, a useful animal model for reproductive studies. METHODS: Levonorgestrel-releasing intrauterine systems were inserted into three reproductively mature, female baboons. The animals were evaluated for 6 months by physical examination and Gram-stained cytology. The vaginal microbiota was characterized at each timepoint by culture-independent analysis of the 16S rRNA-encoding gene. RESULTS: Each baboon harbored a diverse vaginal microbiome. Interindividual variation exceeded intra-individual variation. Diversity declined over time in one baboon and showed mild fluctuations in the other two. There were no significant community differences from early to late post-LNG-IUS placement. CONCLUSIONS: The baboon vaginal microbiome is unique to each individual and is polymicrobial. In this pilot study, the vaginal microbiome remained stable from early to late post-LNG-IUS placement.


Subject(s)
Contraceptive Agents, Female/pharmacology , Intrauterine Devices, Medicated , Levonorgestrel/pharmacology , Microbiota/drug effects , Papio anubis/microbiology , Vagina/drug effects , Vagina/microbiology , Animals , Contraceptive Agents, Female/administration & dosage , Female , Levonorgestrel/administration & dosage , Models, Animal , Molecular Sequence Data , Polymerase Chain Reaction , Prospective Studies , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 16S/metabolism , Sequence Analysis, DNA , Ultrasonography , Uterus/diagnostic imaging
3.
Ann Rheum Dis ; 48(10): 820-8, 1989 Oct.
Article in English | MEDLINE | ID: mdl-2479344

ABSTRACT

Immunohistochemical study showed selective localisation of human epidermal growth factor (hEGF) to the synovial lining layer. Although the synovial lining layer of the rheumatoid, osteoarthritic, and traumatic joints was hEGF positive, hEGF staining was especially dense at the rheumatoid synovial lining layer; the staining increasing linearly according to the degree of stratification of the lining layer (r = 1). Human epidermal growth factor was ultrastructurally localised to cytoplasm, especially to rough endoplasmic reticulum, of the synovial lining fibroblast-like (type B) cell. Only the cell surface of macrophage-like (type A) cells was hEGF positive. When different histological variables were compared with each other a positive correlation was found between hEGF staining of the synovial lining layer and the degree of neovascularisation of rheumatoid synovium (r = 0.72). Although some lymphocytes were weakly hEGF positive, neovascularisation did not correlate with the extent of lymphocyte infiltration or of hEGF staining of lymphocytes. Lymphocyte infiltration or hEGF staining of lymphocytes did not correlate with hEGF staining of the synovial lining layer, whereas the lymphocyte infiltration correlated positively with the extent of perivascular accumulation of lymphocytes (r = 0.89). These findings suggest that (a) hEGF is synthesised by and secreted through endoplasmic reticulum and Golgi apparatus from the synovial lining type B cell; (b) hEGF is at least partially responsible for the pathogenesis of stratification of the rheumatoid synovial lining layer, and perhaps of neovascularisation of the rheumatoid synovium, whereas it is not responsible for lymphocyte accumulation to the rheumatoid synovium.


Subject(s)
Arthritis, Rheumatoid/metabolism , Epidermal Growth Factor/analysis , Synovial Membrane/analysis , Arthritis, Rheumatoid/pathology , Humans , Immunohistochemistry , Lymphocytes/analysis , Neovascularization, Pathologic , Osteoarthritis/metabolism , Osteoarthritis/pathology , Synovial Membrane/blood supply , Synovial Membrane/pathology
5.
Horm Metab Res ; 19(1): 35-7, 1987 Jan.
Article in English | MEDLINE | ID: mdl-3493966

ABSTRACT

In the present study, we have partially purified a characterized epidermal growth factor (EGF)-like substance(s) from human seminal plasma, and determined the concentrations of immunoreactive (IR)-hEGF in seminal plasma from normal and infertile males. Competitive binding curves of seminal plasma extracts were parallel to those of standard hEGF in both radioimmunoassay and receptor assay. Seminal IR-hEGF was similar to standard hEGF by gel exclusion chromatography, isoelectric focusing and sodium dodecyl sulfate polyacrylamide gel electrophoresis. The concentrations of IR-hEGF in normal seminal plasma (48 +/- 9 ng/ml) did not differ from those of infertile males (41 +/- 3 ng/ml); the concentrations of seminal plasma IR-hEGF did not correlate with density, motility or morphology of sperm. These data clearly demonstrate the presence of hEGF in human seminal plasma indistinguishable from hEGF of urinary origin, and suggest that it may not play an important role in the sperm function. The tissue(s) of its origin and its physiological function in the male reproductive organs remain undetermined.


Subject(s)
Epidermal Growth Factor/analysis , Semen/analysis , Adult , Humans , Infertility, Male/metabolism , Male , Radioimmunoassay/methods , Radioligand Assay/methods , Reference Values
6.
Endocrinol Jpn ; 33(4): 433-40, 1986 Aug.
Article in English | MEDLINE | ID: mdl-3491750

ABSTRACT

Human epidermal growth factor (hEGF), a potent growth stimulator of many tissues in culture, has been isolated from human urine and subsequently identified in many human biological fluids including breast milk. In this study, partial purification and characterization of hEGF-like substance(s) in human milk were performed using homologous hEGF radioimmunoassay (RIA) and radioreceptor assay (RRA). hEGF-like material(s) was extracted from pooled human milk by ethanol precipitation, followed by adsorption to cation- and anion-exchange resin. DEAE-Sephadex G-25 ion-exchange chromatography of human milk extracts revealed three major components with hEGF activity (peak I, II, III) eluted with a linear gradient by ammonium acetate. The competitive binding curves for these components were parallel to those for standard hEGF in both RIA and RRA. The apparent molecular weight of peak I was approximately 6,500 and that of peak II and III was approximately 7,000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The pI value for peak I was approximately 4.5 and that for peaks II and III was approximately 5.0 by isoelectric focusing. These data are comparable to the size and charge heterogeneity of hEGF in human urine extracts. In conclusion, the major components of hEGF in human milk appear to be physicochemically, immunologically and biologically (receptor binding activity) indistinguishable from hEGF of urinary origin.


Subject(s)
Epidermal Growth Factor/isolation & purification , Milk, Human/analysis , Female , Humans , Isoelectric Point , Radioimmunoassay , Radioligand Assay
7.
J Biol Chem ; 261(18): 8473-80, 1986 Jun 25.
Article in English | MEDLINE | ID: mdl-2424897

ABSTRACT

The rat liver epidermal growth factor (EGF) receptor was assessed for EGF-dependent autophosphorylation as well as phosphorylation of a defined exogenous substrate in purified plasmalemma and Golgiendosome fractions isolated from rat liver homogenates. While EGF-dependent kinase activity was readily detected in plasmalemma the corresponding activity in Golgi-endosome fractions required detergent. Consequent to the systemic injection of EGF in vivo, the majority (approximately 60%) of receptor as evaluated by 125I-EGF binding was rapidly lost (T 1/2 approximately 8 min) from the plasmalemma and correspondingly accumulated in the Golgi-endosome fraction in a dose-dependent manner. Electron microscope radioautography of 125I-EGF uptake into Golgi-endosome fractions identified internalization into lipoprotein-filled vesicles of heterogenous size and shape but not into stacked saccules of the Golgi apparatus. Evaluation of receptor kinase activity in plasmalemma fractions isolated at various times after EGF injection in vivo showed more rapid loss of EGF-dependent autophosphorylation activity (T 1/2 approximately 10 s) than of receptor content (T 1/2 approximately 8 min). In contrast to the EGF receptor kinase of the plasmalemma fraction, kinase activity accumulating in endosomes was activated, i.e. maximally stimulated, in the absence of EGF or Triton X-100 in vitro. Furthermore, following the peak time of accumulation of EGF receptor kinase in endosomes (5-15 min) EGF-dependent autophosphorylation activity and EGF receptor content were lost more slowly (T 1/2 approximately 27 and 87 min for the loss of autophosphorylation activity and receptor content, respectively). The rapidity of translocation of activated EGF receptor into endosomes (30 s) and the dose response to low levels (1 microgram) of EGF injected are consistent with a physiological role for internalized EGF receptor kinase activity.


Subject(s)
Protein Kinases/metabolism , Receptors, Cell Surface/metabolism , Animals , Dose-Response Relationship, Drug , Enzyme Activation , ErbB Receptors , Golgi Apparatus/enzymology , Kinetics , Liver/enzymology , Male , Microscopy, Electron , Phosphorylation , Phosphoserine/analysis , Phosphothreonine/analysis , Phosphotyrosine , Rats , Rats, Inbred Strains , Tyrosine/analogs & derivatives , Tyrosine/analysis
8.
Endocrinol Jpn ; 33(2): 177-84, 1986 Apr.
Article in English | MEDLINE | ID: mdl-3489609

ABSTRACT

Characteristics of specific receptors for epidermal growth factor (EGF) and its effect on cellular proliferation and synthesis of DNA and protein were studied in cultured vascular smooth muscle cells (VSMC) from rat aorta. Binding studies using 125I-EGF revealed the presence of high affinity binding sites for EGF on VSMC in culture: the apparent dissociation constant was approximately 2.5 X 10(-10)M and the maximal binding capacity was approximately 67,000 sites/cell. EGF stimulated cellular proliferation and incorporation of [3H]thymidine and [3H]leucine into the cells in a dose-dependent fashion; the approximate half-maximal stimulation was induced with 1.5 X 10(-10)M. Platelet-derived growth factor (PDGF) had an additive effect with EGF on DNA synthesis by VSMC. Preincubation of VSMC with unlabeled EGF resulted in a substantial reduction in the number of receptors without changing the affinity, suggesting receptor "down-regulation" mechanism. These data indicate that rat aortic VSMCs have specific receptors for EGF, and suggest that EGF, in addition to PDGF, is also involved in the cell growth of VSMC.


Subject(s)
ErbB Receptors/metabolism , Muscle, Smooth, Vascular/metabolism , Animals , Aorta/drug effects , Aorta/metabolism , Binding, Competitive , Cell Division/drug effects , Cell Survival/drug effects , Cells, Cultured , DNA/biosynthesis , DNA/drug effects , Epidermal Growth Factor/metabolism , Epidermal Growth Factor/pharmacology , ErbB Receptors/drug effects , Male , Mice , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/drug effects , Rats , Rats, Inbred Strains , Time Factors
10.
J Clin Ultrasound ; 13(7): 457-60, 1985 Sep.
Article in English | MEDLINE | ID: mdl-3932475

ABSTRACT

The sonographic textures of 10 parathyroid tumors in nine patients were examined and compared with their histologic features, particularly with the amount of fibrous trabeculae. The carcinomas containing a large amount of fibrous trabeculae, which is the most frequent finding in parathyroid cancer, were very echogenic. On the other hand, the adenomas without fibrous trabeculae showed a low echogenicity. These data suggest that the possibility of malignancy is high when the parathyroid tumor is found to be very echogenic.


Subject(s)
Adenoma/diagnosis , Parathyroid Glands/pathology , Parathyroid Neoplasms/diagnosis , Ultrasonography , Adenoma/pathology , Adult , Female , Humans , Male , Middle Aged , Parathyroid Neoplasms/pathology , Preoperative Care
11.
Horm Metab Res ; 17(9): 448-50, 1985 Sep.
Article in English | MEDLINE | ID: mdl-2995220

ABSTRACT

Using HSDM1 C1 cell line derived from the mouse fibrosarcoma which synthesizes and secretes prostaglandin (PG) E2, specific binding sites for epidermal growth factor (EGF), a potent growth stimulator of many tissues, and its effect on PGE2 production by cultured tumor cells were studied. HSDM1 C1 cell line possessed specific, high-affinity receptors for EGF: Kd (5.5 X 10(-10 M) and binding capacity (17,650 sites/cell). EGF significantly stimulated PGE2 production in HSDM1 C1 line cultured in serum-free medium for 24 h in a dose-dependent manner; a 2.5-fold increase over control was induced by as little as 0.1 ng/ml and the maximal effect (3.5-fold increase) by 1 ng/ml. Its stimulatory effect on PGE2 production was completely blocked by indomethacin, an inhibitor of PG biosynthesis. These data suggest that EGF may be involved in modulation of synthesis and/or secretion of PGE2, a potent bone-resorbing factor, by the tumors which may partly contribute to hypercalcemia in certain types of neoplasms.


Subject(s)
Epidermal Growth Factor/pharmacology , Prostaglandins E/biosynthesis , Animals , Cell Line , Dinoprostone , Epidermal Growth Factor/metabolism , ErbB Receptors , Fibrosarcoma , Indomethacin/pharmacology , Kinetics , Mice , Receptors, Cell Surface/physiology
12.
Acta Endocrinol (Copenh) ; 109(1): 7-12, 1985 May.
Article in English | MEDLINE | ID: mdl-2988259

ABSTRACT

Release of immunoreactive ACTH and beta-endorphin (beta-EP) in response to corticotrophin-releasing factor (CRF) and dopaminergic agents was studied in vivo and in vitro in a patient with Cushing's disease. Iv administration of synthetic ovine (o) CRF significantly stimulated plasma ACTH release, accompanied by increase of plasma cortisol levels. Oral administration of bromocriptine significantly suppressed plasma cortisol levels. Although reduced responses of plasma ACTH and cortisol to o-CRF was observed 1 month after removal of the pituitary adenoma, these normalized 6 months after operation. In vitro perifusion of the pituitary adenoma obtained by surgery revealed that o-CRF also stimulated ACTH and beta-EP release in a dose-responsive manner (10(-9)M 10(-5)M) and that dopamine suppressed their basal secretion. Gel exclusion chromatography of the perfusates showed that the predominant component of ACTH and beta-EP before and after o-CRF stimulation coeluted with standard ACTH and beta-EP, respectively. The present data suggest that o-CRF is a potent secretagogue for ACTH and beta-EP release from the human pituitary adenoma causing Cushing's disease and that ACTH secretion from certain adenomas, possibly originating from the intermediate lobe of the pituitary gland, is partly regulated by a dopaminergic mechanism.


Subject(s)
Adrenocorticotropic Hormone/metabolism , Bromocriptine/pharmacology , Corticotropin-Releasing Hormone/pharmacology , Cushing Syndrome/physiopathology , Dopamine/pharmacology , Endorphins/metabolism , Adenoma/metabolism , Adult , Animals , Dexamethasone/pharmacology , Humans , Male , Metyrapone/pharmacology , Pituitary Neoplasms/metabolism , Receptors, Dopamine/drug effects , Sheep , beta-Endorphin
13.
Horm Metab Res ; 17(4): 205-8, 1985 Apr.
Article in English | MEDLINE | ID: mdl-2861153

ABSTRACT

Release of plasma ACTH- and beta-endorphin (beta-EP)-like immunoreactivity (LI) was studied in vivo in a patient with an ectopic ACTH-producing malignant thymoma. Administration of lysin vasopressin stimulated concomitant release of plasma ACTH- and beta-EP-LI. Administration of cyproheptadine, naloxone, and somatostatin significantly suppressed plasma levels of ACTH- and beta-EP-LI, while saline infusion did not. Gel exclusion chromatography of the plasma extracts revealed that ACTH-LI consisted of two components, large and small molecular weight form, while beta-EP-LI consisted of three components, large molecular weight, beta-lipotropin-, and beta-EP-sized form; each of these components was incompletely suppressed by somatostatin infusion. It is suggested that certain tumors may have acquired aberrant multiple receptors during malignant transformation which may lead to the paradoxical hormone response as demonstrated in this case.


Subject(s)
ACTH Syndrome, Ectopic/blood , Cyproheptadine/pharmacology , Naloxone/pharmacology , Paraneoplastic Endocrine Syndromes/blood , Somatostatin/pharmacology , Adrenocorticotropic Hormone/blood , Adult , Endorphins/blood , Humans , Lypressin/pharmacology , Male , Thymoma/blood , Thymus Neoplasms/blood , beta-Endorphin
15.
Endocrinol Jpn ; 31(5): 619-26, 1984 Oct.
Article in English | MEDLINE | ID: mdl-6097444

ABSTRACT

The effects of bromocriptine, a dopamine agonist, and cyproheptadine, a serotonin antagonist, on basal and corticotropin-releasing factor (CRF)-stimulated ACTH release were investigated in a 40-year-old female patient with Nelson's syndrome. Oral administration of either bromocriptine (2.5 mg) or cyproheptadine (8 mg) caused a marked drop in plasma ACTH levels. Intravenous administration of synthetic ovine (o) CRF (50 micrograms) produced an exaggerated response of plasma ACTH. Short-term (3-week) treatment with either bromocriptine (7.5 mg/day) or cyproheptadine (12 mg/day) resulted in a marked suppression of basal ACTH release. Furthermore, a blunted response of plasma ACTH to oCRF was observed after short-treatment with either drug. However, after a longer period of treatment with cyproheptadine (18-week), plasma ACTH levels rose again and hyperresponsiveness to oCRF was restored to the pretreatment levels. These data indicate that synthetic oCRF is a potent secretagogue for ACTH release in a patient with Nelson's syndrome. It is suggested that bromocriptine and cyproheptadine are effective drugs in reducing basal and CRF-stimulated ACTH release, possibly acting at the pituitary level in this case. However, the apparent refractoriness after chronic treatment with cyproheptadine may limit its therapeutic use in the present case.


Subject(s)
Adrenocorticotropic Hormone/metabolism , Bromocriptine/therapeutic use , Corticotropin-Releasing Hormone/therapeutic use , Cyproheptadine/therapeutic use , Nelson Syndrome/metabolism , Pituitary Neoplasms/metabolism , Adrenocorticotropic Hormone/blood , Adult , Basal Metabolism , Endorphins/blood , Female , Gonadotropin-Releasing Hormone/pharmacology , Humans , Lypressin/pharmacology , Nelson Syndrome/blood , Nelson Syndrome/drug therapy , Thyrotropin-Releasing Hormone/pharmacology , beta-Endorphin
16.
Acta Endocrinol (Copenh) ; 107(1): 125-30, 1984 Sep.
Article in English | MEDLINE | ID: mdl-6091385

ABSTRACT

Using tumour cell lines derived from human bone tumours, specific binding sites for epidermal growth factor (EGF), a potent growth stimulator in many tissues, and its effect on synthesis of prostaglandin (PG) E2, a potent bone-resorbing factor, by cultured osteosarcoma cell line were studied. Three tumour cell lines, one osteosarcoma (HOSO) and two giant cell tumours of the bone (G-1 and G-2), all possessed specific binding sites for 125I-labelled EGF: the apparent dissociation constant was approximately 4-10 X 10(-10) M and the maximal binding capacity was 50 000-80 000 sites/cell. EGF had no mitogenic effect in these cell lines. However, these cell lines did not have specific binding sites for 125I-labelled parathyroid hormone (PTH) or calcitonin. HOSO line produced and secreted PGE2 into medium, while no significant amount of PGE2 was demonstrated in G-1 or G-2 line. EGF significantly stimulated PGE2 production in HOSO line in a dose-dependent manner (0.5-50 ng/ml); its stimulatory effect was completely abolished by indomethacin, an inhibitor of PG biosynthesis. Exogenous PGE1 significantly stimulated cyclic AMP formation in HOSO line, whereas PGF2 alpha, PTH, calcitonin, or EGF had no effect. None of these calcium-regulating hormones affected cyclic AMP generation in either G-1 or G-2 line. These data indicate that human bone tumour cells have specific EGF receptors unrelated to cell growth, and suggest that EGF may be involved in bone resorption through a PGE2-mediated process in human osseous tissues.


Subject(s)
Bone Neoplasms/metabolism , Osteosarcoma/metabolism , Prostaglandins E/biosynthesis , Receptors, Cell Surface/metabolism , Adult , Alprostadil , Animals , Bone Resorption/drug effects , Calcitonin/pharmacology , Cell Line , Child , Cyclic AMP/metabolism , Dinoprost , Dinoprostone , ErbB Receptors , Female , Giant Cell Tumors/metabolism , Humans , Indomethacin/pharmacology , Male , Mice , Parathyroid Hormone/pharmacology , Prostaglandins E/pharmacology , Prostaglandins F/pharmacology
17.
N Engl J Med ; 311(13): 828-32, 1984 Sep 27.
Article in English | MEDLINE | ID: mdl-6472384

ABSTRACT

Despite recognition of the deleterious effects of passive smoking, quantitative information on the intake of environmental tobacco smoke is still lacking. Cotinine is the major metabolite of nicotine found in the urine. We have examined the relationship between urinary cotinine excretion in 472 nonsmokers and the smokiness of their environment. The urinary cotinine levels of nonsmokers who lived with smokers were higher than those of nonsmokers who did not, increasing with the combined daily cigarette consumption of smokers in the family. The urinary cotinine values of nonsmokers who worked with smokers were also higher than those of nonsmokers who did not, increasing with the number of smokers in the workroom. The presence of smokers in both the home and the workplace also increased the cotinine levels. Urban nonsmokers had more cotinine in their urine than rural nonsmokers. We conclude that the deleterious effects of passive smoking may occur in proportion to the exposure of nonsmokers to smokers in the home, the workplace, and the community.


Subject(s)
Cotinine/urine , Pyrrolidinones/urine , Tobacco Smoke Pollution/analysis , Adult , Female , Humans , Male , Middle Aged , Occupational Medicine , Rural Population , Tobacco Smoke Pollution/adverse effects , Urban Population
18.
Endocrinol Jpn ; 30(5): 601-7, 1983 Oct.
Article in English | MEDLINE | ID: mdl-6323154

ABSTRACT

Using seventeen human tumor cell lines derived from a variety of tissues, specific binding sites for epidermal growth factor (EGF), a mouse submandibular gland-derived growth factor, has been characterized. A significant amount of membrane-bound EGF receptors, although considerably varied, was demonstrated in all the tumor cell lines studied. Epidermoid carcinoma appeared to have more EGF receptors than adenocarcinoma. One small cell carcinoma of the lung, one choriocarcinoma of the stomach and three bone tumors also possessed EGF receptors comparable to those of epidermoid carcinoma, while one adenoacanthoma of the stomach had less EGF receptors comparable to adenocarcinoma. Among a variety of phorbol esters tested, tetradecanoyl phorbol acetate, a potent tumor promotor, was shown to be the most effective compound in inhibiting 125I-labeled EGF binding to its receptors. Our results indicate that human tumor cells contain varying amounts of membrane-bound receptors for EGF and that phorbol esters interact with these EGF receptor sites. However, the relationship between EGF receptor sites on tumor cells and cellular proliferation and/or differentiation awaits further study.


Subject(s)
Neoplasms/analysis , Receptors, Cell Surface/analysis , Cell Line , Epidermal Growth Factor/metabolism , ErbB Receptors , Humans , Phorbol Esters/pharmacology , Radioligand Assay , Receptors, Cell Surface/drug effects
20.
J Clin Endocrinol Metab ; 55(6): 1174-7, 1982 Dec.
Article in English | MEDLINE | ID: mdl-6982275

ABSTRACT

Human epidermal growth factor (gEGF), a potent stimulator of the growth of many tissues in culture, has been isolated from human urine and subsequently identified in many human biological fluids. We have partially purified and characterized hEGF-like substance(s) from human cerebrospinal fluid (CSF) and determined the concentrations of immunoreactive (IR) hEGF in CSF obtained from patients with a variety of neurological diseases. Competitive binding curves generated by the CSF samples appeared to be parallel to standard hEGF both in RIA and radioreceptor assays using human placental membrane. Sephadex G-50 gel exclusion chromatography of the CSF extract revealed a single peak of IR-hEGF which coeluted with standard hEGF. The apparent mol wt of the CSF hEGF-like substances(s) was estimated to be 8000 by sodium dodecyl sulfate poplyacrylamide gel electrophoresis, and its approximate pI was 4.5 as determined by isoelectric focusing. The concentrations of IR-hEGF in CSF from patients with pituitary and brain tumors and radiculomyelopathy were significantly higher than those from control subjects, while neither patients with hydrocephalus nor encephalomeningitis had CSF IR-hEGF levels statistically different from the control subjects. The presence of hEGF-like substance(s) in human CSF suggests that it may play an important physiological role in the function of the human nervous tissues but does not provide any evidence of its source.


Subject(s)
Epidermal Growth Factor/cerebrospinal fluid , Adolescent , Adult , Aged , Binding, Competitive , Central Nervous System Diseases/cerebrospinal fluid , Child , Child, Preschool , Chromatography, Gel , Electrophoresis, Polyacrylamide Gel , Female , Humans , Infant , Isoelectric Focusing , Male , Middle Aged , Radioimmunoassay , Radioligand Assay
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