Effect of keratinocyte growth factor—2 on proliferation of human adult keratinocytes

OBJECTIVE: To investigate the proliferative effect of keratinocyte growth factor (KGF-2) on human adult keratinocytes. METHODS: The standard medium was keratinocyte growth medium without bovine pituitary extract (BPE), hydrocortisone or epidermal growth factor (EGF). Keratinocytes from a 48-year-old subject were cultured and seeded on dishes with standard medium of EGF in cell density of 2 x 10(4)/32 mm(2). After 24 hours, the medium was replaced by the standard medium with 0, 4, 16, 125 and 500 ng/ml KGF-2, respectively. The standard medium with EGF was used as the positive control and the standard medium without EGF or KGF-2 was used as the negative controls. The growth of keratinocytes was monitored by 3-(4,5-dimethythiazol-2-yl)-2,5 dipheyl tetrazolium bromide (MTT) assay and by photographs on days 3, 5 and 7, respectively. RESULTS: KGF-2 in concentrations of 4-500 ng/ml showed a significant proliferative effect on days 5 and 7 as compared with that of the negative controls (P < 0.01). On day 3 the cells were proliferated to 1.5-2.5-fold, on day 5 to 3-5-fold and on day 7 to 3-12-fold in KGF-2 medium as that of the negative controls. The optimal response occurred when the concentration of KGF-2 was 125 ng/ml on day 7. Cell proliferation was also consistently higher in all KGF-2 concentrations as compared with that of the positive controls. CONCLUSIONS: KGF-2 has significant effects on the proliferation of adult keratinocytes, which are more effective than that of EGF. This study supports KGF-2 can improve the healing of chronic wounds in adults in clinic.     

表皮生长因子对肿瘤坏死因子α致HaCaT细胞凋亡的抑制作用

目的了解肿瘤坏死因子α（TNF-α）导致HaCaT细胞凋亡过程中过氧化物酶体增殖物激活受体B（PPAR[3）的表达情况，探讨表皮生长因子（EGF）对HaCaT细胞的保护机制。方法将培养的HaCaT细胞分为正常对照组（不作任何处理）、TNF—α小剂量组（10ng／ml TNF-α处理）、TNF—α大剂量组（20ng／mlTNF-α处理）、EGF＋TNF—α小剂量组、EGF＋TNF—α大剂量组，后2组先用20ng／mlEGF培养4h后，再分别予以10、20ng／ml TNF—α处理。采用流式细胞仪检测细胞凋亡情况，半胱氨酸天冬氨酸蛋白酶3（easpase．3）荧光检测试剂盒测定caspase-3的活性，噻唑蓝比色法检测细胞存活率。以5、10、20、40ng／ml的EGF处理HaCaT细胞，采用反转录．PCR和蛋白质印迹法检测PPAR[3mRNA及其蛋白的表达。结果与TNF-α小剂量组[（32±6）％]、TNF-ct大剂量组[（57±6）％]比较，EGF＋TNF—α小剂量组、EGF＋TNF-α大剂量组细胞凋亡率[（20±3）％、（28±4）％]明显下降（P〈0．01），caspase-3活性降低、存活率上升（P〈0．01）。20ng／mlEGF处理细胞时，PPAR[3mRNA及其蛋白表达最强。结论EGF在抑制TNF-α导致的HaCaT细胞凋亡的同时，亦增强细胞中PPARβ的表达。     

Effect of epidermal growth factor (EGF) on a newly established head and neck squamous carcinoma cell line

A new cell line designated 584A2 has been recently established from a patient with squamous cell carcinoma of the larynx. Cytogenetic analysis of the cell line revealed multiple copies of chromosome 7, as well as a homogeneous staining region (HSR) on one chromosome 7. Since overexpression of epidermal growth factor (EGF) cell surface receptors (EGFr) often occurs in other squamous carcinoma cell lines, it was predicted that 584A2 might overexpress EFGr. This was confirmed by: (1) metabolic labeling, with subsequent immunoprecipitation of EGFr and comparing autoradiographs to a cell line without an HSR and fewer copies of chromosome 7, and (2) performing EGF binding assays with Scatchard analysis. Since overexpression of EGFr correlates with an inhibitory effect of EGF on cell culture, the biological effects of EGF on 584A2 were examined in this study. At 5 ng/ml (serum-free medium), EFG stimulated incorporation of [3H] thymidine into trichloroacetic acid-precipitable material compared with controls. Incorporation increased between days 0 to 1 and 1 to 2 days with a 6- to 7-fold maximum. Dose-response studies (0 to 100 ng/ml) indicated maximum incorporation (6- to 7-fold) occurred between 0.1 ng/ml and 1.0 ng/ml. Cell growth was monitored over 7 days and, during this time, 5 ng/ml EGF produced a 10- to 12-fold increase in absolute cell numbers when compared with controls. We concluded that, unlike other squamous carcinoma lines with elevated EGFr, EGF stimulates rather than inhibits 584A2 cell proliferation.     

碱性成纤维细胞生长因子和表皮生长因子对骨骼肌源性干细胞的促增殖效应

目的观察碱性成纤维细胞生长因子（basic fibroblast growth factor，bFGF）和表皮生长因子（epidermal growth factor，EGF）单独及联合应用对骨骼肌源性干细胞（muscle derived stem cells，MDSCs）生长的影响。方法取出生24h内的昆明小鼠15只，采用连续预贴壁法从小鼠后肢肌分离培养MDSCs，用含2％胎牛血清的DMEM培养基促进其向骨骼肌细胞分化。取原代MDSCs及MDSCs分化细胞，采用免疫细胞化学染色检测干细胞标志Sca-1和骨骼肌细胞标志α-Sarcomeric肌动蛋白的表达。HE染色观察细胞肌管形成。MTT比色法检测不同浓度（6．25、12．50、25．00、50．00、100．00ng／ml）的bFGF和EGF单独应用96h对MDSCs增殖的影响以及二者（100．00ng／ml）联合作用24、48、72和96h对MDSCs增殖的影响。结果从新生小鼠后肢肌成功分离培养MDSCs，免疫细胞化学染色90％以上的MDSCs呈Sca-1阳性，分化形成的肌管呈α—Sarcomeric肌动蛋白阳性。HE染色可见肌管形成。bFGF、EGF对MDSCs的促增殖效应随浓度的增加而增加。与阴性对照组比较，bFGF于12．50ng／ml出现促增殖效应（P〈0．05）；25．00ng／ml组与12．50ng／ml组比较，作用提高（P〈0．01）；50．00、100．00ng／ml组较25．00ng／ml组无明显提升（P〉0．05）；EGF的作用与bFGF类似，但于50．00ng／ml时趋于饱和。与阴性对照组比较，EGF于72h、bFGF于96h表现促增殖效应（P〈0．01），而二者联合应用于24h即表现促增殖效应（P〈0．01），并于48、72和96h增殖效应均较单独应用显著提高（P〈0．05）。结论bFGF和EGF都能促进MDSCs的增殖，联合作用更快、更强。     

新生大鼠脑源性神经干细胞培养方法的优化

目的寻求较理想的新生大鼠脑源性神经干细胞(neuralstemcells,NSCs)分离培养方法。方法用不同的接种密度和多种配方的培养基:细胞种植密度采用1×104、1×105、1×106和1×107个/ml4个浓度;培养基除基础成分DMEM/F12外,按照是否添加2%B27、碱性成纤维细胞生长因子(basicfibroblastgrowthfactor,bFGF)、表皮生长因子(epidermalgrowthfactor,EGF)以及开始培养时胎牛血清浓度不同而分别记为第1～8组。分离培养新生大鼠脑源性NSCs并诱导其分化,应用相差显微镜和免疫细胞化学法对其进行观察和比较。结果分离培养出的细胞聚集成神经球,可在体外大量增殖和长期存活,可诱导分化为神经元和神经胶质,具有神经干细胞特性。开始培养时培养液中加入5%胎牛血清有利于NSCs存活,当血清浓度采用10%时,克隆球迅速分化,干细胞收获量极少;干细胞增生速度在种植密度采用1×106个/ml时优于采用其它种植密度时,适当提高其种植密度可加快增生速度;培养基中加入2%B27、bFGF、EGF是必需的,2%B27、20ng/ml的bFGF和EGF同时加入时NSCs生长最好,bFGF和EGF对加快NSCs的增生具有协同作用。结论成功建立了较理想的新生大鼠脑源性NSCs分离培养方法,为进一步研究和应用奠定了基础。     

Regulation of osteosarcoma EGF receptor affinity by phorbol ester and cyclic AMP

We studied the binding and degradation of 125I-labeled epidermal growth factor (EGF) by UMR-106 osteosarcoma cells and the regulation of EGF receptor affinity for EGF by the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and by treatments that raise intracellular levels of cyclic AMP. Cell surface binding of [125I]EGF to A431 cells reached a plateau after a 30 minute incubation at 37 degrees C but was undetectable in UMR-106 cells. Degradation of [125I]EGF proceeded at a 50-fold higher rate in A431 cells on a per cell basis, but receptor-bound [125I]EGF was internalized and degraded at a 3.5-fold higher rate by UMR-106 cells on a per receptor basis. At 4 degrees C, [125I]EGF labeled a single class of surface binding sites in the UMR-106 cell. Treatment with TPA at 37 degrees C reduced subsequent cell surface binding of [125I]EGF at 4 degrees C a maximum of 80% with an IC50 of 1.25 ng/ml. Maximal TPA reduction of [125I]EGF binding was observed within 5-15 minutes and was due to a reduction in the affinity of cell surface receptors of [125I]EGF without a change in receptor density. Pretreatment of the cells for 4 h with 30 microM forskolin, 1 mM isobutylmethylxanthine (IBMX) plus 30 microM forskolin, or 1 mM IBMX plus 100 ng/ml parathyroid hormone (PTH) attenuated the loss in [125I]EGF binding caused by a subsequent dose of 10 ng/ml of TPA by 17% (p less than 0.0005), 39% (p less than 0.0002), and 35% (p less than 0.002), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Epidermal growth factor in renal hypertrophy in streptozotocin-diabetic rats.

Epidermal growth factor (EGF) concentrations in the plasma, kidneys and urine of 31 streptozotocin-diabetic rats and 21 insulin-treated diabetic rats were measured to study the role of EGF in initiating renal hypertrophy in the diabetic rats. Renal hypertrophy occurred from day 7 in the diabetic rats, but not in the insulin-treated rats. Renal EGF was not different between the diabetic and control rats, while that in the insulin-treated rats was significantly less than in the diabetic rats. There were no significant changes in plasma EGF in any of the rats. Urine EGF was 119 +/- 7.9 ng/day at day 7 in the control rats but it was significantly increased from day 2 in the diabetic rats (320 +/- 52.9 ng/day at day 2 and 298 +/- 18.4 ng/day at day 7), while in the insulin-treated rats it was significantly less than that in the diabetic rats (134 +/- 8.34 ng/day at day 2 and 220 +/- 15.2 ng/day at day 7). Since the kidney is the main source of urine EGF and EGF has been shown to induce renal growth both in vitro and in vivo, we conclude that EGF may have initiated renal hypertrophy in diabetic rats.     

Effects of keratinocyte growth factor on skin epithelial differentiation of human amnion epithelial cells

The aim of the present study was to determine the effects of KGF on the differentiation of cultured human amnion epithelial cells (HAECs) towards skin keratinocyte. HAECs at passage 1 were cultured in medium HAM's F12: Dulbecco's Modified Eagles Medium (1:1) supplemented with different concentrations of KGF (0, 5, 10, 20, 30 and 50 ng/ml KGF). Dose–response of KGF on HAECs was determined by morphological assessment; growth kinetic evaluation; immunocytochemical analysis; stemness and epithelial gene expression quantification with two step real time RT-PCR. KGF promotes the proliferation of HAECs with maximal effect observed at 10 ng/ml KGF. However, KGF decreased the stemness genes expression: Oct-3/4, Sox-2, Nanog3, Rex-1, FGF-4, FZD-9 and BST-1. KGF also down-regulates epithelial genes expression: CK3, CK18, CK19, Integrin-β1, p63 and involucrin in cultured HAECs. No significant difference on the gene expression was detected for each Nestin, ABCG-2, CK1 and CK14 in KGF-treated HAECs. Immunocytochemical analysis for both control and KGF-treated HAECs demonstrated positive staining against CK14 and CK18 but negative staining against involucrin. The results suggested that KGF stimulates an early differentiation of HAECs towards epidermal cells. Differentiation of KGF-treated HAECs to corneal lineage is unfavourable. Therefore, further studies are needed to elucidate the roles of KGF in the differentiation of HAECs towards skin keratinocytes.     

Oxidant and antioxidant events during epidermal growth factor therapy to cutaneous wound healing in rats

Cutaneous wound healing is a highly complex process, which includes inflammation, cell proliferation, matrix deposition and remodelling phases. Various growth factors, like epidermal growth factor (EGF), play an important role during wound healing. However, little is known about relationship between EGF and oxidant-antioxidant events in cutaneous wound healing models. Thus we planned to evaluate the connection between EGF therapy and oxidative stress in dermal tissue followed by wounding. Fifty-four adult male Wistar-albino rats were randomly divided into three groups: control, untreated and topical EGF administrated group. A linear full-thickness excision of 40 mm in length on both sides of spinal cord was made on the back of each rat and sutured under anaesthesia and sterile conditions. Excision was closed with 4/0 atraumatic silk suture. EGF solution was freshly prepared at 10 ng/ml dose in thilotears gel under aseptic conditions. Following the surgery, 1 ml of EGF solution was administered to wound strips one time in everyday. The animals were euthanised and wound tissues were collected on days 1, 5, 7 and 14. Thiobarbituric acid reactive substans (TBARS), glutathione (GSH), reactive nitrogen oxide species (NOx), ascorbic acid levels and superoxide dismutase activity were measured spectrophotometrically. TBARS levels decreased and NOx levels increased on day 5 after operation, and GSH levels were increased on day 14 in EGF administered group compared with untreated group. Our data showed that EGF may act like an antioxidant by scavenging toxic oxidation products in wound tissue. In addition, it may contribute healing of the wound tissue in earlier stages and suggest a potential effective role for antioxidant therapies, especially until day 5.     

Effects of FGF-2 and IGF-1 on adult canine articular chondrocytes in type II collagen-glycosaminoglycan scaffolds in vitro

OBJECTIVE: Chondrocyte-seeded tissue engineering scaffolds hold the promise of enhancing certain cartilage repair procedures. The objective of this study was to evaluate the effects of selected growth factors [fibroblast growth factor (FGF)-2 and insulin-like growth factor (IGF)-1] individually and in combination on adult canine articular chondrocyte-seeded type II collagen-glycosaminoglycan (GAG) scaffolds grown in serum-free (SF) medium. DESIGN: Approximately 500,000 second passage chondrocytes were seeded into discs of the scaffold, 4mm diameterx2 mm thick. The constructs were grown in the following media: serum-containing medium; a basal SF medium; SF with 5 ng/ml FGF-2; SF with 25 ng/ml FGF-2; SF with 100 ng/ml IGF-1; and SF with 5 ng/ml FGF-2 plus 100 ng/ml IGF-1. The DNA and GAG contents of the scaffolds were determined after 1 day and 2 weeks and the protein and GAG synthesis rates determined at 2 weeks using radiolabels. Histology and type II collagen immunohistochemistry were also performed. RESULTS: FGF-2 at 5 ng/ml was found to substantially increase the biosynthetic activity of the cells and the accumulation of GAG. The histology demonstrated chondrocytes uniformly distributed through a matrix that stained intensely for GAG and type II collagen after only 2 weeks. Of interest were the rapid degradation of the collagen scaffold, despite the fact that the scaffold was carbodiimide cross-linked, and the contraction of the constructs. There were less pronounced effects using the higher dose of FGF-2 and the combination with IGF-1. CONCLUSIONS: Chondrocyte-seeded type II collagen scaffolds cultured in SF medium supplemented with 5 ng/ml FGF-2 undergo contraction, demonstrate an increase in construct incorporation of radiolabeled sulfate, and display qualitative signs of chondrogenesis.     

In vitro screening of exogenous factors for human neural stem/progenitor cell proliferation using measurement of total ATP content in viable cells

One of the newest and most promising methods for treating intractable neuronal diseases and injures is the transplantation of ex vivo-expanded human neural stem/progenitor cells (NSPCs). Human NSPCs are selectively expanded as free-floating neurospheres in serum-free culture medium containing fibroblast growth factor 2 (FGF2) and/or epidermal growth factor (EGF); however, the culture conditions still need to be optimized for performance and cost before the method is used clinically. Here, to improve the NSPC culture method for clinical use, we used an ATP assay to screen the effects of various reagents on human NSPC proliferation. Human NSPCs responded to EGF, FGF2, and leukemia inhibitory factor (LIF) in a dose-dependent manner, and the minimum concentrations eliciting maximum effects were 10 ng/ml EGF, 10 ng/ ml FGF2, and 5 ng/ml LIF. EGF and LIF were stable in culture medium without NSPCs, although FGF2 was degraded. In the presence of human NSPCs, however, FGF2 and LIF were both degraded very rapidly, to below the estimated minimum concentration on day 3, but EGF remained above the minimum concentration for 5 days. Adding supplemental doses of each growth factor during the incubation promoted human NSPC proliferation. Among other supplements, insulin and transferrin promoted human NSPC growth, but progesterone, putrescine, selenite, D-glucose, and lactate were not effective and were cytotoxic at higher concentrations. Supplementing with conditioned medium from human NSPCs significantly increased human NSPC proliferation, but using a high percentage of the medium had a negative effect. These findings suggest that human NSPC culture is regulated by a balance in the culture medium between decreasing growth factor levels and increasing positive or negative factors derived from the NSPCs. Thus, in designing culture conditions for human NSPCs, it is useful to take the individual properties of each factor into consideration.     

成纤维细胞生长因子和表皮生长因子及复合因子对兔ACL、MCL体外增殖作用

目的观察酸性成纤维细胞生长因子(acid fibroblast growth factor，aFGF)、碱性成纤维细胞生长因子(basic fibroblast growth factor，bFGF)和表皮生长因子(epidermal growth factor，EGF)以及复合因子对兔前交叉韧带(anterior cruciate ligament，ACL)和内侧副韧带(medial collateral ligament，MCL)的促增殖作用。方法分离传代培养10周龄新西兰大白兔骨关节韧带的ACL和MCL的成纤维细胞，接种96孔板，并加入浓度为0(对照组)、1、5、10、50、100ng／ml的aFGF或bFGF，浓度为0(对照组)、1．56、3．13、6．25、12．50、25、50ng／ml的EGF，单独或aFGF EGF两种因子联用与细胞(n=4)共同培养48h，以XTT方法测定其促细胞增殖作用。结果3种生长因子单独应用对ACL和MCL都有促进作用，aFGF对两种细胞均存在量效关系；bFGF 1ng／ml，EGF 5ng／ml对ACL作用最好，而对MCL则是bFGF和EGF均存在量效关系。浓度为5ng／ml的aFGF与50ng／ml的EGF联合1ng／ml aFGF与3．13ng／mlEGF作用于ACL或MCL均有协同作用。结论3种生长因子对ACL和MCL均有促进作用，单独应用aFGF或联用EGF优于单一因子促进兔ACL和MCL细胞的增殖，并且提示低浓度的aFGF联用EGF优于单一生长因子。     

The mitogenic activity of peritoneal tissue repair cells: control by growth factors

The purpose of this study was to determine the proliferative activity of tissue repair fibroblasts recovered directly from injured peritoneum at various times after surgery and to test the mitogenic response of tissue repair cells (TRC) to growth factors. Rabbits underwent bilateral peritoneal abrasion (5 X 5 cm) with sterile gauze until punctate bleeding developed. Postsurgical (Days 2, 5, 7, and 10) tissue repair cells were recovered from the injured peritoneum by scraping with a scalpel blade. Although tissue repair cells consisted of a mixed cell type after 4 days in culture, recovered cells were essentially fibroblasts. These TRC were then pulsed with [3H]thymidine after 4 days in culture. The incorporation of thymidine into Postsurgical Day 5 TRC increased significantly compared to that of Day 2 TRC (P less than 0.05). Incorporation then decreased with time following surgery. Fibroblast growth factor (FGF) and epidermal growth factor (EGF) stimulated the incorporation of thymidine into TRC. However, the response of Postsurgical Day 7 and 10 TRCs to 1 microgram/ml EGF was significantly greater than those of Postsurgical Day 2 and 5 TRCs (Day 2 TRC, 166 +/- 7.4; Day 10 TRC, 420 +/- 96% of control cells without EGF, P less than 0.05). Platelet-derived growth factor (PDGF, 10 ng/ml) also stimulated the incorporation of thymidine into Day 10 TRCs, but this stimulatory activity (129.9 +/- 8.5% of control) was less than EGF or FGF. IL-1 alpha and IL-2 did not stimulate the incorporation of thymidine into TRC at a concentration of 100 pg/ml, but these cytokines did stimulate protein synthesis by TRC.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of epidermal growth factor on sodium-dependent L-alanine transport in LLC-PK1 cells

We evaluated the role of epidermal growth factor (EGF) in the regulation of L-alanine transport in LLC-PK1 renal epithelia. After 2 h of incubation, EGF had no significant effect on L-alanine uptake by LLC-PK1 cells. However, prolonged (16 h) incubation with 2 and 20 ng/ml of EGF resulted in significant increases in sodium-dependent L-alanine uptake as compared with controls. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA; 20 ng/ ml) caused a marked increase in sodium-dependent L-alanine uptake after both 2 and 16 h of incubation, and the treatment with TPA (20 ng/ml) EGF (20 ng/ml) for 16 h resulted in significant acceleration of the TPA-stimulated increase in L-alanine uptake by LLC-PK1 cells. Coincubation with H-7 (20 microM) inhibited both EGF- and TPA-stimulated increases in L-alanine uptake, and genistein (20 microg/ml) blocked the stimulatory effect of EGF in L-alanine transport to the control level. Furthermore, coincubation with cycloheximide (20 microg/ml) for 16 h inhibited both EGF- and TPA-stimulated increases in L-alanine transport to a great extent. The sodium- independent L-alanine uptake was not affected by treatment with either EGF or TPA. These results suggest that the activation of protein kinase C through tyrosine kinase activation plays a role in the EGF effect of stimulating L-alanine transport in LLC-PK1 cells and that the effect is mainly due to increased protein de novo synthesis which occurs after protein kinase C activation.     

表皮生长因子和干细胞因子对小鼠生精细胞增殖与分化的作用

目的:观察表皮生长因子(EGF)和干细胞因子(SCF)体外促小鼠生精细胞增殖、分化的效应。方法:对7~8日龄雄性昆明小鼠生精细胞进行混合细胞体外培养,在培养液中分别添加不同浓度(5、10、20、40、100 ng/ml)的EGF和SCF,并进行EGF和SCF的交互实验,观察生精细胞的存活率和形态学变化,并对粗线期精母细胞特异性磷蛋白基因(P19)、单倍体精子细胞特异性转化蛋白基因(TP1)及染色体倍性进行检测。结果:加入EGF或SCF 2~4 d,各组均可见不同程度的细胞增殖,细胞呈团或族状,以20 ng/ml EGF组和40 ng/ml SCF组最为明显;培养第7天,单一添加20 ng/ml EGF或40 ng/ml SCF组生精细胞数和存活率显著高于与其它各组(P0.05),且40 ng/ml SCF组P19/TP1基因表达显著低于其它各组,单倍体细胞率显著高于其它各组(P0.05)。EGF与SCF配伍时,可显著增加体外培养后生精细胞数(P0.05)。结论:在混合生精细胞体外培养体系中,添加一定浓度的EGF和SCF可显著提高生精细胞数和存活率,而且SCF可提高单倍体精子的形成率;两者交互实验时,对细胞增殖有一定的叠加效应。     

Partial purification of a major type of rat prostatic growth factor: characterization as an epidermal growth factor-related mitogen

The dorsolateral prostate of rats contains a mitogen that shares several properties with epidermal growth factor (EGF), which was designated as prostatic EGF-related mitogen (PEM). PEM was purified about 2,100-fold using molecular-sieve and ion-exchange chromatography. Final preparation stimulated DNA synthesis in BALB/c 3T3 cells at a concentration as low as 1.5 ng/ml and competed with 125I-EGF for binding to cell surface receptors. PEM had a molecular weight of about 14,000 and an isoelectric point of about 4.5, being heat- and acid-stable but inactivated by dithiothreitol. The primary cultured rat dorsolateral prostate epithelial cells required EGF for maximum growth. Partially purified PEM fully substituted for EGF in the primary culture system at a concentration as low as 90 ng/ml. However, the activity of PEM was hardly suppressed by antimouse EGF antiserum. These findings suggest that PEM is a member of the EGF family but has a higher molecular weight (high molecular weight EGF).     

表皮生长因子对子宫内膜细胞体外增殖的影响

本研究观察了表皮生长因子（ＥＧＦ）在体外对子宫内膜上皮细胞及基质细胞增殖的影响。采用酶消化加物理方法分离人子宫内膜上皮细胞及基质细胞,分别在体外培养,细胞汇合后消化,一部分用盖片法培养,用特异性抗体鉴定细胞纯度,另一部分做细胞增殖实验。在细胞中加入不同浓度的ＥＧＦ,培养２４、４８、７２小时,用ＭＴＴ法及流式细胞仪测定ＥＧＦ对子宫内膜上皮细胞及基质细胞增殖的作用。结果：ＥＧＦ浓度为５．０及１０．０ｎｇ／ｍｌ时,明显刺激子宫内膜上皮细胞及基质细胞的增殖,ＭＴＴ与流式细胞仪两法一致。ＥＧＦ不刺激细胞凋亡。结论：采用酶消化结合物理方法分离的人子宫内膜基质细胞及上皮细胞,方法简便、快速,细胞纯度高,在体外生长良好,可用于体外研究着床及异位子宫内膜生长的机制。当ＥＧＦ浓度为５．０及１０．０ｎｇ／ｍｌ时,确实刺激子宫内膜细胞的增殖。     

Growth inhibition of epidermal growth factor-stimulated human glioblastoma cells by nicardipine in vitro.

BACKGROUND: The objective of this work was to observe and analyze the effects of epidermal growth factor (EGF) and the calcium channel antagonist nicardipine on the growth of U251MG, a human malignant glioma cell line, which have high-affinity EGF receptors. METHODS: The growth effects of EGF and nicardipine on U251MG cultured in serum-free and serum-supplemented (10% fetal bovine serum, FBS) medium respectively were observed by MTT colorimeritric analysis. RESULTS: EGF significantly enhanced the growth of U251MG cells in a dose-dependent manner in serum-free medium. The maximal effect was seen at 20 ng/ml. The effects of EGF approximated those obtained in 10% FBS. Nicardipine decreased U251MG cell proliferation, especially in serum-supplemented medium, and completely blocked the growth-stimulated effects of EGF. The combined effects of EGF (10 ng/ml) and nicardipine equaled those of nicardipine alone. CONCLUSIONS: When serum was absent, the U251MG cells showed a pronounced mitogenic response to EGF in a dose-dependent manner, which approximated that achieved with 10% FBS. The addition of serum obscured this effect. Nicardipine suppressed the growth of U251MG cells and completely blocked the growth-stimulated effects of EGF may suggest a possible role of this drug as adjuvant therapy for human malignant gliomas.     

中药三棱对多囊肾病囊肿衬里上皮细胞增殖及上皮生长因于受体磷酸化的影响

目的 探讨中药三棱对体外培养的常染色体显性遗传多囊肾病（ＡＤＰＫＤ）囊肿衬里上皮细胞增殖及上皮生长因子受体（ＥＧＦ－Ｒ）磷酸化的影响。方法 体外培养的囊肿衬里上皮细胞经ＥＧＦ、三棱作用后，采用 Ｂｒｄｕ掺入法测定细胞增殖，流式细胞仪测定细胞周期，Ｗｅｓｔｅｒｎ ｂｌｏｔｔｉｎｇ检测ＥＧＦ－Ｒ磷酸化。结果 与对照组比较，ＥＧＦ（２．５～２０ ｎｇ／ｍｌ）可刺激衬里上皮细胞增殖（Ｐ＜０．０１）；与对照血清比较，三棱含药血清（１％～５％）能明显抑制经ＥＧＦ刺激后的衬里上皮细胞增殖（Ｐ＜００１），阻止细胞从Ｇ_０－Ｇ_１期进入Ｇ_２－Ｍ期，其作用效果呈浓度依赖性；三棱含药血清能抑制囊肿衬里上皮细胞ＥＧＦ－Ｒ的磷酸化（Ｐ＜０．０５）。结论 ＥＧＦ在多囊肾病发病中起促进作用，三棱可能通过对ＥＧＦ－Ｒ磷酸化的干预而达到抑制细胞增殖的作用，从而为延缓多囊肾病的发生与发展提供理论根据。     

NGF与雌激素对离体培养的人头皮毛囊影响的实验研究

目的　观察神经生长因子 (nervegrowthfactor,NGF)、雌激素 (17β E2 )与米诺地尔对离体培养人头皮毛囊生长的影响。方法　建立离体人头皮毛囊培养模型 ,加入NGF、17β E2 和米诺地尔 ,通过目镜测微器测量毛囊长度 ,利用3H TdR掺入检测毛囊 2 4hDNA合成率。结果　NGF(10 0ng ml)与米诺地尔 (12 5 μg ml)对离体培养的人头皮毛囊的生长有促进作用 (P <0 0 5 ) ;而 17β E2 (0 5μg ml)则显示有抑制作用 (P <0 0 5 ) ;NGF与雌激素组毛囊的生长长度与阴性对照比则无明显变化(P >0 0 5 ) ;3H TdR掺入检测与长度检测结果完全一致。结论　NGF(10 0ng ml)与米诺地尔 (12 5 μg ml)对离体培养的人头皮毛囊的生长有促进作用 ,而 17β E2 (0 5ng ml)则显示有抑制作用 ,NGF(10 0μg ml)可干预 17β E2 (0 5 μg ml)抑制毛囊生长的影响。