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1.
Lymphocytes from dog peripheral blood have been stimulated in vitro with 3 different mitogens (Con A, PHA and PWM). Culture medium was RPMI 1640 enriched with either autologous plasma, fetal calf serum or a newly described defined serum substitute. In such cultures the number of surviving and activated cells was measured by cytofluorometry and the proliferation was assessed by thymidine incorporation. In unstimulated cultures, up to 70% of all cells had disappeared (died) during the first 42 hours of incubation, whereas the number of viable cells was reduced to 50–60% in mitogen stimulated cultures. Of the surviving lymphocytes, between 25–40% of the cells appeared to have an elevated RNA-content (activated or G1 cells). By comparison between thymidine incorporation and number of mitogen induced G1 cells, a very high correlation was found (r=0.92). However, the slope of the regression line was much lower than expected. The low thymidine incorporation per activated cell was primarily related to the high cell death and a resulting dilution of tritiated thymidine. Indeed, preliminary results suggested that the same thymidine incorporation per G1b cells could be obtained if peripheral blood lymphocytes were washed immediately before pulsing as could be obtained with lymphnode cells without washing.  相似文献   

2.
Lymphocyte transformation test is a powerful tool in laboratory testing of immunologic competence of animals. The impaired function of the lymphocytes or presence of mitogenesis suppressing factors in the patient serum were detected by comparing lymphocyte transformation (expressed as thymidine incorporation) obtained in media containing either autologous, homologous, or fetal calf serum additions. Most valuable results were obtained by using at least two, preferably three, different phytomitogens: concanavlin A (Con A), pokeweed mitogen (PWM), and pl ytohemagglutinin (PHA) at optimal concentrations (Con A, 15 μg/ml, PWM and PHA, 5 μg/ml) and decreased concentrations (Con A, 5 μg/ml, PWM and PHA, 1 μg/ml). Mitogenesis induced by lipopolysaccharide was considerably smaller and not used routinely. With 2 × 105 lymphocytes/well, the background count of unstimulated lymphocytes in autologous serum in healthy dogs was usually between 100 and 400 counts/min (CPM), in clinically healthy cattle and horses from 200 to over 2000 CPM. Higher CPM were rarely detected without clinical disease. Increased background counts were often associated with viral infections, leukemias and lymphoreticular hyperplasias, decreased background counts were associated with various diseases. The stimulation indexes (SI) of healthy animals in autologous serum with Con A, (5 μg/ml) or PWM or PHA (1 μg/ml) were in the range from 100 to 1000 in the dogs, in the tens for Con A and in hundreds for PWM and PHA in horses and cattle. Increased SI were present during the incubation period of various diseases. Decreased SI were associated with numerous infectious and lymphoreticular diseases and were caused by any of the following: (1) the presence of serum immunosuppressive factor(s) in the patient serum, (2) the decreased response of lymphocytes to mitogens, or (3) increased mitogenicity of lymphocytes due to unidentified serum factors in absence of phytomitogens.  相似文献   

3.
In vitro blastogenesis of dog and fox lymphocytes was compared by a microculture technique. The highest 3H-thymidine incorporation in cultures of dog lymphocytes was observed at day 3, while in those of fox at day 2, incubated either at 37 degrees C or at 39 degrees C. Lymphocytes cultured at 39 degrees C incorporated more tritiated thymidine than did cells cultured at 37 degrees C. The stimulation index (SI) of dog peripheral blood lymphocytes to both mitogens concanavalin A (Con A) and leucoagglutinin (LA) was in a similar range, while pokeweed mitogen (PWM) showed a weaker but significant stimulatory action. The blastogenesis of fox lymphocytes was the greatest in Con A stimulated cultures. The mitogenic potency of LA and PWM was about half of that of Con A, with no essential difference between them. Maximum lymphocyte proliferation of dog and fox was observed when culture media were supplemented with 10% fetal calf serum (FCS).  相似文献   

4.
The value of [3H]-thymidine incorporation as a measurement for mitogen induced proliferation of dog peripheral blood lymphocytes (PBL) has been examined. The cells were cultured in RPMI 1640, enriched with 10% autologous plasma for 48 hours at 37 degrees C, 5% CO2 and 95% relative humidity. Under these conditions a great variability in [3H]-thymidine incorporation was observed. By analysis of CPM and number of activated cells (G1), it was found that comparable number of G1 cells were generated in human and dog PBL. Also, the membrane transport of thymidine was very similar for lymphocytes of the two species. Nevertheless, a low [3H]-thymidine incorporation by dog PBL was frequently seen, and this phenomenon could be related to a release of soluble substance(s) within the cultures. When the cultured cells were washed and resuspended in fresh medium immediately before pulsing, the expected CPM per G1 cell could be obtained. Since it has been described in the literature that macrophages can produce cold thymidine in macrophage enriched lymphocyte cultures, the in vitro response of non-adherent dog PBL was analyzed. Mitogen stimulation of such non-adherent cells resulted in CPM per G1 cells very similar to those obtained with washed cells. Based on these data, it is suggested that the production of cold thymidine might be one of the technical problems related to cultures of lectin stimulated dog PBL in vitro and it should be taken into consideration, if [3H]-thymidine incorporation is used as the only measure of lymphocyte proliferation.  相似文献   

5.
Calf bone marrow cells cultured in a semi-solid medium of 0.8% methyl cellulose produced colonies of granulocytic cells and macrophages by seven days. A prerequisite for colony growth was the presence of serum obtained from a calf three hours after intravenous injection of endotoxin. Three morphological types of colonies were seen but cell types within these types of colonies did not differ. Cultured cells were identified by morphological and cytochemical characteristics.

Optimum growth occurred when serum from endotoxin stimulated calves and fetal calf serum were present in a volumetric ratio of 7:3. Inhibition of colony growth occurred when endotoxin-stimulated serum was present at greater than optimum concentration. Normal calf serum, fetal calf serum, mouse L-cell conditioned medium and bovine urine did not stimulate significant colony growth when 8.0 x 104 marrow cells were cultured.

There was a linear relationhip between the number of marrow cells in the cultures and the number of colonies produced. Colony forming efficiency ranged from 13 to 59 colonies per 105 cells plated.

The behaviour of calf colony forming units in suspension culture was similar to that reported for mouse colony forming units.

  相似文献   

6.
The objective of this study was to explore the underlying mechanism of insulin‐like growth factor 1 (IGF‐1)–caused cell proliferation of rumen epithelium in goats fed a high metabolizable energy (ME) diet. In this study, young goats were fed either a low ME [LL, n = 9, ME: 0.57 MJ/kg0.75/day] or high ME [HL, n = 9, ME: 1.00 MJ/(kg0.75/day)] diet for 42 day. The time duration of G1‐phase was shortened as a result of enhanced expression of cyclin D1 mRNA in the HL group (p < 0.05). It was suggested that a high ME diet promoted cell transition from G0/G1 to S‐phase via cyclin D1. The level of phosphorylation of ERK was higher in HL than LL group (p < 0.05). In cell culture, the ERK was phosphorylated by IGF‐1 treatment. The proliferative effects of insulin‐like growth factor 1 (IGF‐1, 25 ng/ml) on [3H] thymidine (TdR) incorporation into DNA and on cyclin D1 protein expression of rumen epithelial cells were inhibited by PPP (the inhibitor of type 1 IGF receptor) (p < 0.05) and ERK inhibitor (p < 0.05) in vitro. Thus, IGF‐1 up‐regulated cyclin D1 expression and accelerated G1‐phase progression in the cell cycle through Ras/Raf/MEK/ERK pathway in rumen epithelium of goats.  相似文献   

7.
Levamisole and its influence on the immune response of lambs   总被引:1,自引:0,他引:1  
Ten parasite-free lambs were drenched with 8 mg/kg of levamisole on days 0 and 28 and were injected with human erythrocytes and ovalbumin one day after each drench. Ten other antigen-injected lambs were not drenched with anthelmintic as controls. Lymphocytes from the control and drenched lambs were culturedin vitro with RPMI 1640 plus 5% fetal calf serum (FCS), with 50% autologous serum only, with concanavalin A (Con A) or with phytohaemagglutinin (PHA). Decreased blastogenesis was observed in cells from the drenched lambs cultured in the presence or absence of mitogen and was most obvious when 50% autologous serum was used, particularly with PHA, and when lymphocytes were collected 3 and 7 days after the first and 3 days after the second antigen injection. There were no significant changes in antibody titres between the groups. Decreased serum complement activity was seen 3 days after the second antigen injection in the drenched lambs. Although there was a significant reduction in the serum insulin-like growth factor I levels 4 days after each levamisole drench, the drenched lambs gained significantly more weight than the non-drenched control lambs.Abbreviations Con A concanavalin - EIA enzyme immunoassay - FCS fetal calf serum - GH growth hormone - IGF-I insulin growth factor I - PHA phytohaemagglutinin  相似文献   

8.
供体细胞周期同步化是影响体细胞核移植成功率的重要因素之一.试验分别对绵羊卵丘细胞采用血清饥饿和接触抑制的方法进行细胞周期同步化处理,使用流式细胞仪检测各组细胞周期的分布.结果发现,与对照组相比,卵丘细胞经血清饥饿24~72 h后,显著地增加了G0/G1期细胞的百分比(P <0.05);接触抑制24~72 h,G0/G1期细胞所占比例与血清饥饿组无显著差异(P >0.05),但显著高于对照组(P <0.05);用经血清饥饿与接触抑制的供体细胞进行核移植后,重构胚卵裂率、桑椹胚率和囊胚率差异不显著(P >0.05),但二者囊胚率显著高于对照组(P <0.05).上述结果证实,血清饥饿和接触抑制均能使绵羊卵丘细胞周期同步化至G0/G1,均可用作绵羊体细胞核移植的供体细胞细胞周期同步化处理.  相似文献   

9.
A microculture technique was developed for the in vitro blastogenesis of feline lymphocytes. Blastogenesis of ficoll-diatriazoate gradient separated mononuclear cell, washed blood and whole blood were compared. In general the whole blood cultures yielded higher stimulation indices (SI) than the washed blood or separated mononuclear cell cultures.The effect of several variables on the stimulation of lymphocyte cultures was examined. A cell concentration of 3 × 105 cells/well and a 1:20 dilution of washed and unwashed whole blood gave optimal stimulation with concanavalin A (Con A). Phytohaemagglutinin-P (PHA-P) did not give significant levels of stimulation. Inactivated fetal calf serum (FCS) at levels of 2.5% (for washed blood) and 5% (for separated mononuclear cell and whole blood) gave highest SI. Supplementation with FCS was preferable to autologous, homologous or horse sera for all cultures. Optimal SI was obtained in all cultures incubated for 3 days and labelled with 1 μCi tritiated thymidine (3H-TdR) for the last 16 hours. The highest SI were in the range of 70 to 105 (18,764 to 42,681 counts per minute (CPM) for separated mononuclear cell culture, 100 to 165 (28,403 to 45,334 CPM) for washed blood culture and 105 to 186 (41,076 to 69,999 CPM) for whole blood culture.  相似文献   

10.
Nitrate (NO3¯) is an effective non‐protein nitrogen source for gut microbes and reduces enteric methane (CH4) production in ruminants. Nitrate is reduced to ammonia by rumen bacteria with nitrite (NO2¯) produced as an intermediate. The absorption of NO2¯ can cause methaemoglobinaemia in ruminants. Metabolism of NO3¯ and NO2¯ in blood and animal tissues forms nitric oxide (NO) which has profound physiological effects in ruminants and has been shown to increase glucose uptake and insulin secretion in rodents and humans. We hypothesized that absorption of small quantities of NO2¯ resulting from a low‐risk dose of dietary NO3¯ will increase insulin sensitivity (SI) and glucose uptake in sheep. We evaluated the effect of feeding sheep with a diet supplemented with 18 g NO3¯/kg DM or urea (Ur) isonitrogenously to NO3¯, on insulin and glucose dynamics. A glucose tolerance test using an intravenous bolus of 1 ml/kg LW of 24% (w/v) glucose was conducted in twenty sheep, with 10 sheep receiving 1.8% supplementary NO3¯ and 10 receiving supplementary urea isonitrogenously to NO3¯. The MINMOD model used plasma glucose and insulin concentrations to estimate basal plasma insulin (Ib) and basal glucose concentration (Gb), insulin sensitivity (SI), glucose effectiveness (SG), acute insulin response (AIRg) and disposition index (DI). Nitrate supplementation had no effect on Ib (p > .05). The decrease in blood glucose occurred at the same rate in both dietary treatments (SG; p = .60), and there was no effect of NO3¯ on either Gb, SI, AIRg or DI. This experiment found that the insulin dynamics assessed using the MINMOD model were not affected by NO3¯ administered to fasted sheep at a low dose of 1.8% NO3¯ in the diet.  相似文献   

11.
The aim was to evaluate the relationship of prepartum plasma estrone sulfate (E1S) and estradiol‐17β (E2β) concentrations with the weight of the calf and the placental parameters. Holstein–Friesian cows (n = 33) inseminated artificially with Japanese Black beef bull semen at Hiroshima University Farm in Japan were used for the experiment. Blood samples were taken every day from day 270 of gestation until the day after calving. The plasma samples were analyzed for E1S and E2β by enzyme immunoassay. The calf birth weight was taken immediately after calving. Complete fetal membranes were collected from 19 cattle and the weights of the placental components and the number of cotyledons were recorded. All 33 cattle delivered singleton normal calves. The prepartum plasma E1S concentration was found to correlate significantly (P < 0.01) with the calf birth weight (r = 0.83), total fetal membrane weight (r = 0.81), cotyledonary weight (r = 0.79) and inter‐cotyledonary membrane weight (r = 0.64), but it did not correlate significantly with the number of cotyledons, whereas prepartum plasma E2β was not found to correlate significantly with the weight of either the calf or any of the placental components except the number of cotyledons. In conclusion, prepartum plasma E1S, not plasma E2β, was found to correlate significantly with the weight of the calf and the placental components.  相似文献   

12.
Three distinct waves of Leydig cell development are found in the pig testes, which occur during fetal, perinatal, and prepubertal periods. Proliferation of Leydig cells is primarily regulated by luteinizing hormone (LH); however, effects of LH on proliferation of immature rat Leydig cells are mediated by specific growth factors and cytokines such as transforming growth factor-alpha (TGFalpha), insulin-like growth factor-1 (IGF-1), interleukin-1beta (IL-1beta), steroidogenesis-inducing protein (SIP), and TGFbeta. The objective of the present study was to identify growth factors that could possibly be involved in the proliferation of Leydig cells in the neonatal pig testis. Leydig cells were isolated from 3- to 5-d-old pig testes, cultured for 48 hr in serum-free media, washed, and treated with hCG and/or IGF-1, epidermal growth factor (EGF), IL-1beta, SIP, and TGFbeta for 18 hr. Tritiated thymidine incorporation into DNA was assessed over a subsequent 4-hr period. Incorporation of [3H]-thymidine was stimulated by hCG treatment with a 2.3-fold increase over control cultures. SIP also induced a significant increase (P < 0.0001) in the incorporation of [3H]thymidine into Leydig cell DNA. Similarly, EGF and IGF-1 also increased DNA synthesis in neonatal porcine Leydig cells, whereas IL-1beta had no effect. TGFbeta had very little, if any, effect on DNA synthesis when added alone, but inhibited the stimulatory effects of other mitogens (SIP, hCG, EGF/TGFalpha, and IGF-1). Our results indicate that these growth factors may play a role in the LH/hCG-dependent proliferation of Leydig cells during the perinatal period of development.  相似文献   

13.
Purinoceptors are membrane‐bound receptors for adenosine, purines and pyrimidines that are expressed in nearly all cell types throughout the organism. Previous studies demonstrated that they are involved in the regulation of proliferation of most target cells. Since it is well known that several purinoceptors are expressed in skin keratinocytes, we were interested in examining their involvement in wound healing. Primary skin keratinocytes from four different mouse strains were isolated and cultured for in vitro studies. The expression patterns of metabotropic purinoceptors of the primary cells as well as a murine cell line were determined by RT‐PCR analysis. The specificity of the amplification products was verified by sequence analysis. Proliferation assays with various purinoceptor agonists and antagonists were performed using the murine cell line MSC‐P5. Cell proliferation was determined by incorporation of 5‐bromo‐2‐deoxyuridine (BrdU). Female NMRI mice were used for in vivo trials. To inhibit the wound healing process, animals were treated once daily with dexamethasone. After a week of treatment, full thickness wounds were set with biopsy punches in depilated back skin. The wound healing process was measured by determination of the wound area and the incorporation of BrdU in vivo. The purinoceptor agonists and antagonists were administered topically on the wound area. Among the examined metabotropic purinoceptors, the murine cell line MSC‐P5 expressed the receptors A2b, P2Y1, P2Y2 and P2Y6. Primary cultured murine keratinocytes possessed the same expression profile and they additionally expressed the P2Y4 receptor. Furthermore, three of the four primary cultures showed a splicing variant of the P2Y2 receptor. The purinoceptor agonists ATP, UTP and 5’‐(N‐ethyl)‐carboxamidoadenosine (NECA) enhanced the cell growth of the murine cell line MSC‐P5. The mitogenic effect of ATP and UTP was inhibited by the P2Y1, P2Y2 and P2Y6 receptor antagonist suramin, while the effect of NECA was inhibited by the selective A2b receptor antagonist enprofylline. Taking into account that other tested purinoceptor agonists, 2‐Me‐S‐ATP and UDP, exhibited no proliferative activity on MSC‐P5 cells, it can be concluded that ATP and UTP act on proliferation via the P2Y2 receptor, and NECA via the A2b receptor. In vivo trials in an animal model of impaired wound healing confirm that pharmacological actions via purinoceptors offer an intriguing possibility in the treatment of wounds. Nevertheless, further investigations are needed to fully elucidate the role of purinergic mechanisms involved in wound healing. Funding: Self‐funded.  相似文献   

14.
The aim of this work was to investigate developmental changes in cell proliferation and apoptosis in normal duck bursa of Fabricius using flow cytometry and immunohistochemistry. Studies were carried out on Tianfu ducks on days 24 and 27 of embryogenesis (E24 and E27) along with days 20, 70, and 200 of postnatal development (P20, P70, and P200). Results showed that the percentage of G0/G1 bursa cells significantly increased between E24 and P200 while the percentage of cells in the S phase or G2 + M phase as well as the proliferating index obviously decreased during the same period. Proliferation cell nuclear antigen was detected in lymphocyte and interfollicular epithelium. The proliferative lymphocyte density tended to decrease from E24 to P200. Apoptotic bodies in macrophages, free apoptotic bodies, or nuclei with condensed chromatin in lymphocytes in follicles were identified by transferase-mediated dUTP nick-end labeling. Both flow cytometry and microscopic analysis reveal that the proportion of apoptotic cells and apoptotic lymphocyte density increased from E24 to P20, fell on P70, then rose again on P200. Our foundings demonstrate that cell proliferation decreases and apoptosis increases with age. These changes may account for duck bursa development and involution.  相似文献   

15.
Ten parasite-free lambs were drenched with oxfendazole on days 0 and 28 and, one day after each drench, were injected with human erythrocytes and ovalbumin. Ten other antigen-injected lambs were not drenched (controls). Lymphocytes collected 3 days after each antigen injection and cultured in RPMI 1640 plus 5% fetal calf serum (FCS) and lymphocytes collected 3 days after the first and 3 and 7 days after the second antigen injection and cultured in 50% autologous serum had decreased blastogenic activity compared with control lymphocytes. After the second drench, decreased blastogenesis was seen with lymphocytes collected on days 3 and 7 and cultured in 5% FCS and concanavalin A (Con A) and on day 3 when cultured in 5% FCS and phytohaemagglutinin (PHA). Decreased blastogenesis was also seen with lymphocytes collected 7 and 29 days after the second injection of antigen and cultured in 50% autologous serum plus Con A and on days 3, 7 and 29 when cultured in 50% autologous serum and PHA.Significantly depressed antibody responses to both antigens were seen after the second drench. The serum complement level was depressed 3 days after the second injection of antigen. Serum nitric oxide levels were significantly depressed 3 and 21 days after the first and 7 and 21 days after the second injection of antigen. There were no differences in levels of growth-promoting hormones but the drenched lambs gained significantly more weight than the controls.Abbreviations C complement - Con A concanavalin A - cpm counts per minute - EIA enzyme immunoassay - FCS fetal calf serum - IGF insulin-like growth factor - oIGF-1 ovine insulin-like growth factor-1 - PBS phosphate-buffered saline - PHA phytohaemagglutinin  相似文献   

16.
Optimal conditions for stimulation by phytohaemagglutinin (PHA) were established for equine, porcine, ovine and human lymphocytes in MEMS medium. Optimal thymidine concentration was determined for assay of cell transformation. With all species tested horse serum gave highest thymidine incorporation. Homologous serum was not more appropriate for lymphocytes of man, pig and sheep. Optimal stimulation was achieved at 20, 0.5–5, 5, and 10–40 μg PHA per 106 cells for human, equine, porcine and ovine lymphocytes, respectively.  相似文献   

17.
Trophoblast from Day-14 bovine embryos was cultured in medium containing mitogens to determine if the mitotic index could be altered. Trophoblast from each of 15 embryos was cultured in minimum essential medium (Eagles) with 20 % fetal calf serum (control) or in this medium supplemented with pokeweed mitogen (1 %, v/v), phytohemagglutinin (1 %, v/v), concanavalin A (1 %, v/v) or thymidine (2 mg/ml). No mitogenic effect was observed due to any of the treatments. However, mitotic indexes were significantly lower when pokeweed (P < 0.05) or thymidine (P < 0.01) was added to the medium. A highly significant (P < 0.001) variation in mitotic index between embryos was observed.  相似文献   

18.
A method for examining lymphocyte blastogenesis in whole blood cultures of neonatal calves is presented. Considerable variation in magnitude of thymidine incorporation was noted between animals but the general trend of response was uniform. Maximum responses occurred at different culture times for each mitogen. In a standard 0.2 ml micro culture system using 10,000 mononuclear cells per culture incubated for 96 hours in 5 per cent fetal bovine serum maximum mitogenic responses were obtained with 0.8 microgram phytohaemagglutinin per culture, 1 microgram concanavalin A per culture and 0.08 microgram pokeweed mitogen per culture.  相似文献   

19.
A cat with epitheliotrophic T‐cell lymphoma with paraneoplastic eosinophilia is described. Initial attempts to control the disease with conventional therapies failed. The addition of recombinant human interferon α2b (rhINFα2b) resulted in a clinical, haematogenous and sonographic improvement for 49 days. The overall survival time from initial diagnosis was 100 days. Relapse was correlated with the development of serum antibodies directed against rhINFα2b. To our knowledge, this is the first report describing the clinical use of IFNα in the treatment of neoplasia in the cat.  相似文献   

20.
A study was conducted on twenty indigenous goat kids allocated into two different groups. All animals were offered ad libitum rice straw and berseem hay (40:60). Group I (T1) was fed concentrate mixture (100 g/d). Group II (T2) was supplemented with urea molasses mineral block (200 g/d). The experiment lasted for 90 days. There was significant decrease in serum sodium (60.68 mEq/L), increase in serum potassium (34.50 mEq/L) and increased activity of AST (340.42 U/L) and ALT (164.96 U/L) was observed in kids of group T2 in comparison to the controls (T1). On histopathological examination mild degenerative changes in kidney of group T2 with congestion in intertubular vessel, granular cytoplasm of the epithelial cells in PCT and DCT, necrosis and swelling of the epithelial cells, congestion of vessels and cloudy swelling was observed in PCT and DCT. Albuminious mass was also present in tubule. On histopathological observation of liver of kid of group T2 oedema in liver parenchyma and proliferation of fibrious tissue in periportal area was observed.  相似文献   

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