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1.
Recent studies have emphasized the crucial role of gut microbiota in triggering and modulating immune response. We aimed to determine whether the modification of gut microbiota by oral co‐administration of two antibiotics, ampicillin and neomycin, would lead to changes in the antibody response to antigens in chickens. Neonatal chickens were given or not given ampicillin and neomycin (0.25 and 0.5 g/L, respectively) in drinking water. At 2 weeks of age, the chicks were muscularly or orally immunized with antigenic keyhole limpet hemocyanin (KLH), and then serum anti‐KLH antibody levels were examined by ELISA. In orally immunized chicks, oral antibiotics treatment enhanced antibody responses (IgM, IgA, IgY) by 2–3‐fold compared with the antibiotics‐free control, while the antibiotics did not enhance antibody responses in the muscularly immunized chicks. Concomitant with their enhancement of antibody responses, the oral antibiotics also lowered the Lactobacillus species in feces. Low doses of antibiotics (10‐fold and 100‐fold lower than the initial trial), which failed to change the fecal Lactobacillus population, did not modify any antibody responses when chicks were orally immunized with KLH. In conclusion, oral antibiotics treatment enhanced the antibody response to orally exposed antigens in chickens. This enhancement of antibody response was associated with a modification of the fecal Lactobacillus content, suggesting a possible link between gut microbiota and antibody response in chickens.  相似文献   

2.
甲哨唑对鸡细胞免疫和体液免疫功能的作用   总被引:3,自引:0,他引:3  
本试验观察了甲硝唑对鸡细胞免疫和体液免疫功能的作用,并与左旋咪唑进行了比较。结果表明2.5-400mg/kg甲哨唑可显著促进鸡外周血T淋巴细胞增殖,但对B淋巴细胞无明显影响;可使CD4^ /CD8^ 淋巴细胞比值明显升高;可使鸡外周血淋巴细胞诱生IL-2活性明显增强;可使鸡体内抗颗粒性胸腺依赖性抗原SRBC抗体滴度、抗可溶性胸腺依赖性抗原BSA抗体滴度和抗非胸腺依赖性抗原BA抗体滴度明显升高;可使鸡血清总补体活性明显升高。与甲硝唑比较,左旋咪唑也存在着非常类似的作用,2.5-10mg/kg左旋咪唑可明显促进外周血T淋巴细胞增殖,可使CD4^ /CD8^ 淋巴细胞比值明显升高;可使鸡外周血淋巴细胞诱生IL-2活性明显增强;可使鸡体内抗SRBC抗体滴度、抗BSA抗体滴度和抗BA抗体滴度均明显升高;10mg/kg左旋咪唑甲硝唑可使血清补体总活性升高。上述结果表明甲硝唑和左旋咪唑两种咪唑类化合物在促进鸡细胞免疫和体液免疫可能存在着相似的作用机制。  相似文献   

3.
A variety of immunologic techniques have been introduced during the past few years. Many of these techniques are being applied to clinical specimens in an attempt to help the practicing veterinarian make a diagnosis. The introduction of new techniques requires extensive testing with clinically normal and diseased patients. It is essential for the practicing veterinarian to understand that the techniques available for the detection of immunologic disorders in the dog and cat are not routine diagnostic procedures and that adequate information has not been developed for any of the techniques described to assure the clinical significance of either positive or negative results (Table 3). This should not discourage the practitioner from submitting samples, but should encourage him or her to question the significance of those results and to attempt to correlate them with history and clinical signs before arriving at a final diagnosis.  相似文献   

4.
Q fever is a zoonosis caused by the intracellular bacterium Coxiella burnetii. Both humoral and cellular immunity are important in the host defence against intracellular bacteria. Little is known about the immune response to C. burnetii infections in domestic ruminants even though these species are the major source of Q fever in humans. To investigate the goat’s immune response we inoculated groups of pregnant goats via inhalation with a Dutch outbreak isolate of C. burnetii. All animals were successfully infected. Phase 1 and Phase 2 IgM- and IgG-specific antibodies were measured. Cellular immune responses were investigated by interferon-gamma, enzyme-linked immunosorbent spot test (IFN-γ Elispot), lymphocyte proliferation test (LPT) and systemic cytokines. After two weeks post inoculation (wpi), a strong anti-C. burnetii Phase 2 IgM and IgG antibody response was observed while the increase in IgM anti-Phase 1 antibodies was less pronounced. IgG anti-Phase 1 antibodies started to rise at 6 wpi. Cellular immune responses were observed after parturition. Our results demonstrated humoral and cellular immune responses to C. burnetii infection in pregnant goats. Cell-mediated immune responses did not differ enough to distinguish between Coxiella-infected and non-infected pregnant animals, whereas a strong-phase specific antibody response is detected after 2 wpi. This humoral immune response may be useful in the early detection of C. burnetii-infected pregnant goats.  相似文献   

5.
Reciprocal cellular and humoral immune responses in bovine tuberculosis   总被引:7,自引:0,他引:7  
A sandwich ELISA for the detection of gamma interferon showed higher sensitivity and specificity than an indirect ELISA for mycobacterial antibodies in the diagnosis of bovine tuberculosis. Circumstantial evidence of an inverse relationship between cellular and humoral immune responses to Mycobacterium bovis was found in cattle with natural infection.  相似文献   

6.
Colostral immunity to colibacillosis in the neonatal calf   总被引:2,自引:0,他引:2  
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7.
Mucosal and tracheal washings from pigs vaccinated parenterally and intranasally with Aujeszky's disease virus were tested for specific anti-Aujeszky's disease virus responses. Antibody tests included complement dependent antibody lysis, antibody dependent cellular cytotoxicity, virus neutralisation, and anti-Aujeszky's disease virus IgA and IgG levels. There was no correlation between the levels of these antibodies and protection from subsequent challenge. Direct lymphocyte cytotoxicity against cells infected with Aujeszky's disease virus was found in lymph nodes draining the tonsillar area.  相似文献   

8.
The shot biopsy is a common experimental technique for the collection of samples to investigate muscle tissue characteristics or to determine meat quality features in pigs. Its application seems to be also possible in interdisciplinary research projects investigating animal stress, behaviour, and welfare. The present study on 12 group-housed pigs (age: 12 weeks, weight: 29.3 kg) shows the influence of this wound-causing technique on different humoral and cell-mediated parameters of the immune system at 1, 3, 5, and 9 days after biopsy compared to the initially investigated levels before. An enhancement of the blood sedimentation rate and both the IgG and the cellular immune response in vivo (leukocytes, lymphocytes) as well as in vitro (ConA) was observed. Furthermore, there were signs of a secondary wound infection 5 days after biopsies were taken possibly caused by mutual oral manipulation of the animals. We conclude that the muscle shot biopsy technique can be used on group-housed pigs as a method to investigate muscle physiological characteristics. The technique, however, induces immunological reactions which may interfere with stress-induced immune reactions.  相似文献   

9.
Animal immunity is usually impaired in obesity. We know little about the effect of being overweight or obese on the immune function of wild rodents. The present study is aimed to test the hypothesis that immunity is suppressed in overweight Mongolian gerbils (Meriones unguiculatus). In the study, 16 overweight (body mass: 90.8–127.6 g) and 16 lean gerbils (body mass: 60.5–77.7 g) were randomly selected from a total of 174 male gerbils (body mass range: 55.8–144.7 g). Half of the overweight and lean males were injected with sterile saline; the others were immunochallenged (IC) with phytohaemagglutinin and keyhole limpet hemocyanin to assess cellular and humoral immunity, respectively. Body fat mass, wet and dry spleen mass, leukocyte counts, blood glucose levels and serum leptin levels were significantly higher in the overweight gerbils than in the lean gerbils. However, phytohemagglutinin response indicative of cellular immunity and immunoglobulin G concentrations was significantly lower in the IC overweight gerbils than in the IC lean gerbils. These results indicate that cellular and humoral immunity are impaired in the overweight gerbils. Excessive body fat mass, higher leukocyte counts and serum leptin levels imply that overweight gerbils are in a low grade inflammatory state.  相似文献   

10.
Humoral and cellular immune responses to inactivated swine influenza virus (SIV) vaccine were evaluated and compared. Fifty 3-week-old weaned pigs were randomly divided into the non-vaccinated control group and vaccinated group containing 25 pigs each. Pigs were vaccinated intramuscularly twice with adjuvanted UV-inactivated A/SW/MN/02011/08 (MN/08) H1N2 SIV vaccine at 6 and 9 weeks of age. Whole blood samples for multi-parameter flow cytometry (MP-FCM) and serum samples for hemagglutination inhibition (HI) assay were collected at 23 and 28 days after the second vaccination, respectively. A standard HI assay and MP-FCM were performed against UV-inactivated homologous MN/08 and heterologous pandemic A/CA/04/2009 (CA/09) H1N1 viruses. While the HI assay detected humoral responses only to the MN/08 virus, the MP-FCM detected strong cellular responses against the MN/08 virus and significant heterologous responses to the CA/09 virus, especially in the CD4+CD8+ T cell subset. The cellular heterologous responses to UV-inactivated virus by MP-FCM suggested that the assay was sensitive and potentially detected a wider range of antigens than what was detected by the HI assay. Overall, the adjuvanted UV-inactivated A/SW/MN/02011/08 H1N2 SIV vaccine stimulated both humoral and cellular immune responses including the CD4-CD8+ T cell subset.  相似文献   

11.
In the present study, we investigated the effects of a daily 5 min restraint stress of pregnant sows in the last five gestational weeks on the development and reactivity of the immune system of the offspring. Maternal stress resulted in significant decreased serum immunoglobulin G (IgG) concentrations in suckling piglets at 1 and 3 days of age. Furthermore, the stress treatment of the sows had an immunosuppressive effect on lymphocyte proliferation in response to the T-cell mitogen concanavalin A (ConA) at postnatal days 1 and 7. A suppressive effect was also found in response to the B-cell mitogens lipopolysaccharid (LPS) at days 1 and 35 and pokeweed mitogen (PWM) at day 1 of life, whereas natural killer (NK) cell cytotoxicity was not altered by prenatal stress. The relative thymus weights were significantly reduced in prenatally stressed piglets on the first and 35th day of life and the morbidity and mortality during the suckling period were significantly increased in prenatally stressed litters, as shown by a higher frequency of diseased and died piglets per litter. In addition, the ConA-, LPS- and PWM-stimulated lymphocyte proliferation at the age of 7, 21 and 35 days, and the NK cell cytotoxicity at the age of 21 and 35 days decreased in prenatally stressed and in control piglets 1h after a corticotropin (ACTH) injection. However, the cellular immunity was always higher in the control piglets which might be a result of the weaker stress hormone reactivity in prenatally stressed animals. In conclusion, the results provide first experimental evidence that prenatal maternal stress during late gestation is able to impair both humoral and cellular immune function in suckling piglets. The data also suggest that gestational stress in pigs may affect the ontogeny of the foetal immune system with consequences on the susceptibility to diseases and immune responsiveness to stressful stimuli of the offspring.  相似文献   

12.
Canine infections with Leishmania infantum represent a considerable veterinary medical and public health problem. In this study, immunoglobulin G1 (IgG1) and IgG2 specific humoral responses were measured and compared with the delayed type hypersensitivity (DTH) cellular response to a leishmanin, in three groups of dogs clinically and serologically characterised as: (I) asymptomatic and direct agglutination test (DAT)-seronegative; (II) asymptomatic and DAT-seropositive; (III) DAT-seropositive and symptomatic. IgG2 was regarded as a marker of disease, since significantly higher levels of this subclass were recorded in the symptomatic dogs. In contrast, the IgG1 response could not be related to clinically relevant infection. A high correlation was observed between IgG2 level and DAT titre; the correlations between IgG1 and IgG2 levels, and between IgG1 level and DAT titre were lower. This may indicate that IgG2 is the main subclass in the specific humoral response which is detected by the DAT. A reduced IgG2 response, albeit not significantly different, was recorded among dogs with clear cellular immune responses detected by a DTH positive reaction. Furthermore, no correlations were observed between cellular response measured by DTH and humoral responses quantified by DAT titre or IgG1 and IgG2 levels. Combining serology and DTH skin test is a practical procedure to assess anti-Leishmania immune responses in dogs.  相似文献   

13.
The objective of this study was to determine the stimulating effect of the Inter Yeast S dietary supplement on selected parameters of specific and non-specific humoral and cellular immunity in lambs. The study involved 32 lambs aged 30 +/- 3 days, divided into two equal groups: II--control, and II--experimental. Experimental group animals were fed a C-J concentrate mixed with a prebiotic, the Inter Yeast S, commercially available, containing dried brewer's yeast Saccharomyces cerevisiae in the amount of 3 g/kg of the concentrate. At the beginning of the experiment (day 0) and on the 15th, 30th and 60th day of the study, blood was sampled from the jugular vein to determine selected parameters of biochemical, specific and non-specific humoral and cellular immunity in lambs (total protein levels, gamma globulin levels, lysozyme activity, ceruloplasmin activity, proliferative response of blood lymphocytes (MTT) after stimulation with LPS or ConA, the metabolic activity (RBA) and potential killing activity (PKA) of phagocytes). As regards humoral immunity parameters, significantly higher gamma globulin levels and higher lysozyme and ceruloplasmin activity were found in blood serum of experimental lambs administered the Inter Yeast S, compared with those determined in control lambs not fed the supplement. No statistically significant differences in serum total protein were found between the control and experimental groups. An analysis of cellular immunity indicators revealed significantly higher levels of RBA and PKA, and higher proliferative response of blood lymphocytes (MTT) after stimulation with LPS and ConA in the experimental group, compared with those observed in the control group.  相似文献   

14.
Chagas disease has a high incidence in Mexico and other Latin American countries. Because one of the most important known methods of prevention is vector control, which has been effective only in certain areas of South America, the development of a vaccine to protect people at risk has been proposed. In this study, we assessed the cellular and humoral immune response generated following immunization with pBCSP and pBCSSP4 plasmids containing the genes encoding a trans-sialidase protein (present in all three forms of T. cruzi) and an amastigote specific glycoprotein, respectively, in a canine model. Thirty-five beagle dogs were divided randomly into 5 groups (n = 7) and were immunized twice intramuscularly with 500 μg of pBCSSP4, pBCSP, pBk-CMV (empty plasmid) or saline solution. Fifteen days after the last immunization the 4 groups were infected intraperitoneally with 500 000 metacyclic trypomastigotes. The fifth group was unimmunized/infected. The parasitaemia in the immunized/infected dogs was for a shorter period (14 vs. 29 days) and the parasite load was lower. The concentration of IgG1 (0.612 ± 0.019 O.D.) and IgG2 (1.167 ± 0.097 O.D.) subclasses was measured (absorbance) 15 days after the last immunization with both recombinant plasmids, the majority of which were IgG2. The treatment of parasites using the serum from dogs immunized with pBCSP and pBCSSP4 plasmids produced 54% (± 11.8) and 68% (± 21.4) complement-mediated lysis, respectively. At 12 h post immunization, an increase in cytokines was not observed; however, vaccination with pBCSSP4 significantly increased the levels of IFN-γ and IL-10 at 9 months post-infection. The recombinant plasmid immunization stimulated the spleen cell proliferation showing a positive stimulatory index above 2.0. In conclusion, immunization using both genes effectively induces a humoral and cellular immune response.  相似文献   

15.
This study was conducted to determine effects of dietary supplementation with a Chinese herbal ultra-fine (CHU) powder on cellular and humoral immunity in early-weaned piglets. Sixty piglets weaned at 21 days of age were randomly assigned to one of 3 treatment groups representing supplementation with 0 or 2 g/kg of the powder, or 0.2 g/kg of colistin (an antibiotic) to maize- and soybean meal-based diets (n = 20). On days 7, 14 and 28 after initiation of the treatment, lymphocyte proliferating activity and serum levels of antibodies and cytokines were measured. Results indicated that the powder enhanced (P < 0.05) serum concentrations of IL-2, IL-6 and TNF- on days 7 and 28, and of IgG and IgM on day 28, as well as the proliferating activity of blood lymphocytes in vivo on all days relative to the none additive group. Addition of the powder (7.82 to 31.25 mg/ml) to culture medium in vitro also increased (P < 0.05) the proliferating activity of blood lymphocytes compared with the none additive group. These findings indicate a beneficial effect of the CHU powder on cellular and humoral immune responses in piglets.  相似文献   

16.
贵州南五味子多糖对鸡细胞免疫和体液免疫的影响   总被引:1,自引:0,他引:1  
选用600只15日龄海兰褐雏鸡,随机分为5个处理,每个处理3个重复,每个重复40只鸡,皮下注射贵州南五味子多糖10、20mg/kg、黄芪多糖20mg/kg、环磷酰胺40mg/kg及生理盐水。空白对照组,连续给药3d后免疫新城疫疫苗,分别于免疫后7、14、21、28和35d时,各处理组随机抽取8只鸡检测各项免疫指标,探讨不同处理组对雏鸡免疫功能的影响。本试验结果表明,皮下注射10~20mg/kg贵州南五味子多糖可显著促进鸡外周血T淋巴细胞增殖,IL-2的产生(P<0.01);可使CD4+/CD8+淋巴细胞比值明显升高(P<0.01);可使鸡体内抗ND抗体滴度明显升高(P<0.01);可使法氏囊、胸腺的脏器指数均明显升高(P<0.01)。  相似文献   

17.
The effects of challenge exposure on the humoral and cellular immune responses in pseudorabies vaccinated swine were studied in 84 barrows. The pigs were divided into seven groups and challenge exposed to a virulent strain of pseudorabies virus on months 1, 3, 5, 8, 10, 12 and 14 after vaccination. The pigs were vaccinated with commercial attenuated and inactivated pseudorabies virus vaccines. The protection conferred by vaccination was equally effective with both types of vaccines. The levels of cellular and humoral immunity after challenge exposure in pigs vaccinated with either type of vaccine were similar. The cell-mediated immune response can be effectively used for the early detection of pigs exposed to pseudorabies virus. Virus isolation attempts from the brain and spleen in most of the vaccinated pigs were unsuccessful.  相似文献   

18.
Intracutaneous injection of a crude supernatant fraction from homogenised Salmonella typhimurium SVA 44 (O 4, 5, 12) or S dublin SVA 47 (O 9, 12) elicited highly significant (P less than 0.005) double skin-fold thickness increases in calves spontaneously infected with salmonella and verified as excretors. The use of isolated structurally defined outer membrane components from salmonella bacteria established that the delayed skin reactions could be elicited by either the lipopolysaccharide which contains O-antigenic polysaccharide chains homologous to the infecting strain, or an outer membrane protein fraction (porin). The porin preparation gave rise to skin reactions regardless of which salmonella serotype the calf was infected with. Histological examination of biopsy material indicated a delayed skin reaction. No such reactions were seen in biopsies from control calves. The use of lipopolysaccharide permitted a salmonella serogroup specific skin test although the endotoxic side effects were marked in doses above 50 micrograms. Purified O-antigen specific polysaccharides devoid of lipid A from S typhimurium (O 4, 12) or S enteritidis (O 9, 12) failed however to elicit skin reactions. Infected calves had humoral antibody titres against the O antigen of the infecting strain which were significantly (P less than 0.005) higher than those found in control calves.  相似文献   

19.
20.
Mycobacterium avium spp. paratuberculosis (MAP) causes a persistent infection and chronic inflammation of the gut in ruminants leading to bacterial shedding in feces in many infected animals. Although there are often strong MAP-specific immune responses in infected animals, immunological correlates of protection against progression to disease remain poorly defined. Analysis of cross-sectional data has suggested that the cellular immune response observed early in infection is effective at containing bacterial growth and shedding, in contrast to humoral immune responses. In this study, 20 MAP-infected calves were followed for nearly 5 years during which MAP shedding, antigen-specific cellular (LPT) and humoral (ELISA) immune responses were measured. We found that MAP-specific cellular immune response developed slowly, with the peak of the immune response occurring one year post infection. MAP-specific humoral immunity expanded only in a subset of animals. Only in a subset of animals there was a statistically significant negative correlation between the amount of MAP shedding and magnitude of the MAP-specific cellular immune response. Direct fitting of simple mechanistic mathematical models to the shedding data suggested that MAP-specific immune responses contributed significantly to the kinetics of MAP shedding in most animals. However, whereas the MAP-specific cellular immune response was predicted to suppress shedding in some animals, in other animals it was predicted to increase shedding. In contrast, MAP-specific humoral response was always predicted to increase shedding. Our results illustrate the use of mathematical methods to understand relationships between mycobacteria and immunity in vivo but also highlight problems with establishing cause-effect links from observational data.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0204-1) contains supplementary material, which is available to authorized users.  相似文献   

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