Analysis of the humoral immune response to Oestrus ovis in ovine

Antibody responses (IgG, IgM and IgA) against Oestrus ovis were analyzed in sheep and in first year grazing lambs from Sardinia (Italy) by an indirect-enzyme-linked immunoassay test and L2 O. ovis excretory/secretory antigens. Serum samples from 208 sheep were obtained prior to be slaughtered, and then heads were removed and cut open along their longitudinal axis to collect the parasites from the nasal cavities, turbinates and sinus. Besides this, blood samples were monthly collected from the lambs of G-1 (maintained under field conditions) and the lambs of G-2 (kept housed since birth to avoid Oestrus infestations) throughout a year. In the sheep, a positive significant correlation was observed between the number of first instar O. ovis larvae and the values of IgM, and between the second instar larvae and the IgG optical densities. In the lambs, all classes of antibodies increased significantly from July in G-1. The highest values of IgG were reached in September (IgG) and decreased in November-December. The IgM response peaked in November, and very low values of IgA were observed during the study. Matching these data with chronobiology of O. ovis in this region, we conclude that the first infection occurs on May, stimulating the production of humoral antibodies. The reduction of the IgG antibody levels starting from October means the beginning of the diapause while the IgM response seems to be associated to the presence of L1 in the nasal cavities. The data obtained led us to forecast an early treatment of the ovine on June-July, which should keep away from the maturation of O. ovis L1 larvae, avoiding the development of clinical lesions and interrupting the life cycle of this parasite.     

Interference of the humoral immune response against resident and nonresident intestinal commensal strains in weaning pigs

Not nocuous bacteria are important for the maturation and the modulating activity of the gut immune system. However, the humoral immune response against commensal and probiotic bacteria is less documented, particularly in farmhouse animals. Blood serum and saliva were collected in two trials where probiotics, Lactobacillus rhamnosus GG (LbR), well-defined human isolate (Trial A), and a novel and abundant porcine commensal, Lactobacillus sobrius strain 001^T (LbS) (Trial B), were supplemented to weaning pigs. Anti-LbR IgA were present in serum of pigs before treatment with LbR, but also after 1 or 2 weeks in control pigs, notwithstanding the absence of DNA from LbR in colon. Pigs fed or not LbS for 1 or 2 weeks had LbS-specific IgA, in saliva and in serum. Colon contents of control subjects were positive for DNA from LbS. We hypothesized that part of this IgA strain-specific activity is partially related to immune cross-reactivity between different Lactobacillus-species. With the procedure of Shu et al. [Shu, Q., Bird, S.H., Gill, H.S., Rowe, J.B., 1999. Immunological cross-reactivity between the vaccine and other isolates of Streptococcus bovis and Lactobacillus. FEMS Immunol. Med. Microbiol. 26, 153–158], after ELISA test on blood serum or saliva pre-incubated with LbR or LbS, each strain blocked a relevant part of IgA specific for the other. So bacteria with different affinity for the pig present reciprocal crossed immune activity. When probiotics are supplied to weaning pigs, the possible action of already present multi-effective IgA should be considered. The mechanism of IgA induction by certain probiotics needs to be addressed in further studies.     

Equine humoral immune response to Rhodococcus (Corynebacterium) equi

An enzyme-linked immunosorbent assay was developed to test equine serum for the presence of antibodies to Rhodococcus (Corynebacterium) equi. Experimental ponies had no detectable antibody to R equi before exposure to the bacterium. After experimental inoculation, animals in groups that received live R equi subcutaneously or intranasally/intratracheally developed high titers to R equi. Noninoculated controls remained seronegative. Serum was also collected from horses of various ages that were naturally exposed to R equi. There was a wide range of anti-R equi titers in these horses. Because experimentally infected horses seroconverted when some naturally infected foals did not seroconvert, the function of antibody in resistance to R equi infection remains unknown.     

Cellular and humoral immune response of foals to vaccination with Corynebacterium equi.

Transformation of peripheral blood lymphocytes from pony foals vaccinated and subsequently infected with Corynebacterium equi was studied. Three foals were vaccinated on two occasions using a formalinized C. equi vaccine with aluminum hydroxide as an adjuvant. Three nonvaccinated foals served as controls. Foals were challenged intratracheally with 9 x 10(9) C. equi six weeks after the initial vaccination.Foals survived this infection for one to two weeks. Significant lymphocyte transformation in response to C. equi antigens was detected in two vaccinated foals at the third week after initial vaccination and in all vaccinated animals at the fifth week. No statistically significant transformation was seen in nonvaccinated foals before infection. Vaccinated and nonvaccinated foals showed responsive lymphocytes following challenge. Vaccination offered no obvious protection against experimental challenge but this failure was probably due to an excessive infective dose of organisms. Low levels of humoral antibodies were detected in some challenged foals. The pathological changes in the lungs of infected animals were comparable with, but more fulminating than, changes observed in the natural disease.     

Cell-mediated and humoral immune response of chickens to Mycoplasma synoviae.

The leukocyte migration-inhibition test was employed to demonstrate the presence of cell-mediated immunity and to ascertain its relation to immunoglobulin production in Mycoplasma synoviae infection in chickens. With peripheral leukocytes and a preparation of M. synoviae used as antigen, good discrimination was obtained between naturally or experimentally infected birds and uninfected control birds. Only the infected groups showed significant inhibition. Positive migration inhibition values developed in the second week of infection, often before the appearance of hemagglutination-inhibition titers, and continued to accompany the production of immunoglobulins with some degree of correlation for at least 6 or 12 months.     

Modification of humoral immune response in chickens following treatment with carrageenan

Carrageenan treatment of chickens resulted in splenomegaly and enlargement of bursa but had no effect on the thymus. The dose and route of administration had a profound effect on humoral immune response to Brucella abortus and sheep red blood cells. Antibody response to B. abortus was either unaffected or significantly enhanced, whereas response to red blood cells was severely suppressed. Furthermore, delineation of the class of antibody response affected by the treatment, using 2-mercaptoethanol, suggested that there was a selective inhibition of IgG response to the T dependent antigen.     

The humoral immune response of lambs experimentally infected with Mycoplasma ovipneumoniae

Using sera from lambs experimentally infected with Mycoplasma ovipneumoniae and Pasteurella haemolytica, the development of a good humoral immune response to M. ovipneumoniae was detected by ELISA. The antibody titres peaked 41 days post-infection and good antibody titres were maintained over the 16-week experimental period. Immunoblotting revealed that antibodies to specific antigens appeared in the sera in a sequential manner, some being seen shortly after infection and others developing only after a substantial time lag. Antibodies were raised against almost all the major antigens detected in one laboratory strain (956/2) and against all antigens previously shown to be conserved in 22 Scottish field isolates of M. ovipneumoniae.     

The intestinal and serum humoral immune response of mice to orally administered antigens in liposomes: II. The response to liposome-entrapped bacterial proteins.

Effective oral adjuvants are needed to improve the intestinal immune responses to oral vaccines that are based on relatively low molecular weight antigens refined from veterinary pathogens. Liposomes prepared by different methods and composed of phospholipids of varying transition temperature were used to entrap cholera toxin (CT) and fed to mice. No significant increase in the intestinal antibody nor the serum IgA antibody response was detected but levels of serum IgG anti-CT antibody were significantly elevated in the group fed CT in phosphatidylcholine-based liposomes. Levels of antibody were significantly reduced in the groups fed CT in dipalmitoylphosphatidylcholine liposomes. Escherichia coli wall extract (ECWE) entrapped in certain liposome types and fed to mice elicited significantly increased serum anti-ECWE antibody responses but intestinal antibody responses were insignificantly different from the controls. These results suggest that orally administered liposomes fail to act as potent intestinal adjuvants for the entrapped antigens of bacterial origin used in this study.     

雏鸡应用益生素后免疫器官体液免疫动态变化

本实验应用免疫酶组织化学法系统地研究了雏鸡饲喂益生素后,其免疫器官的体液免疫动态变化.研究结果发现雏鸡应用益生素后,法氏囊和脾脏IgG、IgM、IgA生成细胞数量均比未饲喂益生素的对照组有不同程度增加,其中IgM、IgA生成细胞数量于饲喂益生素后7 d达到峰值,IgG生成细胞数量于饲喂益生素后10 d达到峰值.表明益生素能够增强雏鸡免疫器官的体液免疫功能.     

饲喂益生素雏鸡新城疫疫苗免疫后外周血液的体液免疫变化

为了研究益生素与疫苗的体液免疫增强联合效应,应用免疫SPA菌体花环法、间接ELISA法对饲喂益生素雏鸡ND疫苗免疫后,其外周血液B淋巴细胞数量、IgG、IgM和IgA含量的动态变化进行了较全面系统地研究。结果发现,应用益生素的雏鸡ND疫苗免疫后7d内,其上述被检指标显著高于ND疫苗单独免疫雏鸡(p0.05),表明益生素可提高雏鸡外周血液对ND疫苗的体液免疫应答能力。益生素Ⅰ组雏鸡外周血液的体液免疫指标又略高于益生素Ⅱ组雏鸡,说明益生素Ⅰ的疫苗免疫增强效果优于益生素Ⅱ。     

Lymphocyte transformation and humoral immune factors in Basenji dogs with immunoproliferative small intestinal disease

Serum protein concentrations and 4 immunologic factors were determined in 5 Basenji dogs with immunoproliferative small intestinal disease. There was no correlation between the total serum proteins, immunoglobulin G and immunoglobulin M concentrations, and physical health status of the animals. The severity of clinical signs correlated roughly with decrease in albumin and increase in globulin concentrations. The main changes were detected in beta- and fast gamma-globulins. The total hemolytic complement levels were decreased in the 2 most severely affected animals below the minimal laboratory values observed in healthy animals. Alteration in the intrinsic responsiveness of lymphocytes to various mitogens did not correlate with progression in severity of the disease. Correlation between the appearance of blastogenesis-suppressing substances in serum and the severity of the disease was only partial: Sera (at 20% concentration) from the 2 most severely affected dogs completely suppressed blastogenesis induced by all 3 mitogens. The sera of 3 other dogs either did not suppress or suppressed only concanavalin A-induced mitogenesis and to a lesser extent phytohemagglutinin-induced mitogenesis without correlations to the overall clinical status. The disturbances of immunologic mechanisms were detected after the appearance of clinical disease, were not considered the cause of immunoproliferative small intestinal disease, may represent a manifestation of the secondary infection, and may contribute to aggravation of the clinical course.     

Dynamics of the humoral immune response of calves infected and re-infected with Cooperia punctata

The dynamics of the humoral immune response of calves were analysed after primary infection and re-infection with the intestinal nematode Cooperia punctata. 12 male 5 month-old Holstein-Friesian calves were randomly divided into two groups A and B. At the beginning of the experiment Group A animals were each infected experimentally with a single oral dose of 130,000 infective third stage larvae (L3) of C. punctata. The animals of Group B were kept as non-infected controls. The two calves from Group A with the highest infections died of cooperiosis at 32 and 44 days after infection (DAI), respectively. On DAI 100 the calves were treated with the recommended dose of oxfendazole. On DAI 180 the remaining four calves of Group A and three animals of Group B (B1) were infected with 260,000 L3 of C. punctata, while the other three calves of Group B (B2) served as non-infected controls. Monitoring of the humoral immune response predominantly demonstrated an IgG1 response against both adult and L3 antigen of C. punctata. Moreover, re-infections increased the levels of these immunoglobulins. IgA levels were less increased than IgG1 and no significant increase was observed in IgG2 and IgM levels. Immunoblotting analysis showed that total IgG present in the serum of the primary infected animals mainly reacted against adult proteins of 12-14 and 17-20 kDa and against L3 proteins of 33 and 43 kDa. After re-infection total IgG reacted with the same adult proteins but also with an adult 29 kDa protein.     

The intestinal and serum humoral immune response of mice to systemically and orally administered antigens in liposomes: I. The response to liposome-entrapped soluble proteins.

The development of oral vaccines is of great importance in veterinary medicine and new adjuvants and carriers are essential to this aim. Liposomes are effective systemic adjuvants but the relatively little data on their potential as oral adjuvants is inconclusive. Liposomes containing ovalbumin (OA) were effective adjuvants when administered intraperitoneally to mice. Feeding mice with OA or keyhole limpet haemocyanin in liposomes in a series of priming and boosting regimes failed to elicit any significant increase in serum or intestinal antibody response compared with feeding the free antigen. Oral tolerance induction to systemic challenge was also unaffected by OA entrapment in liposomes. In vitro liposome stability assays at 37 degrees C demonstrated a substantial resistance to disruption in the presence of acidic stomach contents. However, the addition of bile caused a rapid and profound release of protein marker from the liposomes. The rate and degree of disruption was influenced by the type of phospholipid used. These results suggest that liposomes may be useful as carriers for orally administered compounds but they are ineffective as adjuvants for the non-particulate, naturally weak immunogens used in this study.     

Development of an immunoassay to measure the humoral immune response of hybrid striped bass Morone chrysops x M. saxatilis

Hybrid striped bass (HSB) were immunized with bovine serum albumin (BSA) and the specific anti-BSA immunoglobulin (Ig) was affinity purified from the resulting serum by means of an agarose gel-BSA column. The native Ig had an apparent molecular size of 893 KDD, by size exclusion chromatography, and when examined by polyacrylamide gel electrophoresis (PAGE) under denaturing conditions, resolved to heavy (H) and light (L) chains of 76 and 27 KDD, respectively. Affinity purified native HSB Ig was used to immunize a goat which produced specific anti-HSB Ig antibody (Ab). Purified native HSB Ig was also used to produce two murine monoclonal antibodies (mAbs) with specific affinities for H and L chain moieties of the HSB Ig molecule. Both polyclonal and monoclonal antibodies could be used individually in an indirect enzyme-linked immunosorbent assay (ELISA) to measure specific anti-BSA Ig in HSB serum. These antibodies could also be used in combination to measure total Ig in a capture ELISA format. Using both assays, the kinetics of the humoral immune response of HSB was measured for 98 days following two injections of BSA.     

Detection by ELISA of the humoral immune response in rabbits naturally infected with Trichophyton mentagrophytes

An indirect enzyme linked immunosorbent assay (ELISA) was developed and its diagnostic potential evaluated for rabbits infected by Trichophyton mentagrophytes. Within-run and between-run coefficient of variance varied from 2.3 to 7.7% and from 5.9 to 8.5%, respectively, indicating satisfactory reproducibility of the ELISA. There was no significant cross-reaction with antigens of Microsporum canis, Malassezia pachydermatis and Aspergillus fumigatus. The level of specific IgG to Trichophyton mentagrophytes was measured in sera of 25 11-week-old and 12 younger infected rabbits. There was no significant difference in the IgG level between 12 5-week-old infected rabbits and controls (p = 0.38). The antibody response was higher in 12 7-week-old rabbits compared with controls (p = 0.001). The IgG level in 25 11-week-old rabbits differed from the controls very significantly (p < 0.0001). Increased specific IgG in 11-week-old rabbits exhibited 96% sensitivity and 94% specificity. Predictive values of a positive and a negative test were 96 and 94%, respectively. Western immunoblotting associated three protein bands (21.5, 31, 44 kDa) with Trichophyton mentagrophytes infection.     

The mucosal humoral immune response of the horse to infective challenge and vaccination with equine herpesvirus-1 antigens.

Equine herpesvirus-1 (EHV-1) remains a frequent cause of upper respiratory tract infection and abortion in horses worldwide. However, little is known about the local antibody response elicited in the upper airways of horses following exposure to EHV-1. This study analysed the mucosal humoral immune response of weanling foals following experimental infection with virulent EHV-1, or vaccination with either of 2 commercial vaccines. Twenty weanlings were assigned to 5 groups and were inoculated with, or vaccinated against, EHV-1 following different regimens. Finally, all weanlings were simultaneously challenged intranasally with virulent EHV-1 Army 183 (A183). Nasal wash and serum samples were collected at regular intervals until 13 weeks after final challenge. Nasal washes were assayed for EHV-1-specific equine IgGa, IgGb, IgG(T), IgA, IgM and total virus-specific antibody using an indirect, quantitative ELISA. Total serum antibody responses were also monitored, and clinical signs of EHV-disease were recorded for each individual. Virus-specific IgA dominated the mucosal antibody response elicited in weanlings inoculated with A183, being detectable at up to 3.1 microg/mg total IgA 13 weeks after challenge. Neither inactivated EHV-1 administered i.m., nor attenuated EHV-1 administered intranasally induced detectable mucosal antibodies. EHV-1-specific mucosal antibodies impeded EHV-1 plaque formation in vitro. Such virus-neutralising antibody probably contributes to a reduction of shedding of EHV-1 from the respiratory tract of virus-infected horses.     

Cell mediated and humoral immune response of chickens to inactivated oil-emulsion infectious bronchitis vaccine

A lymphocyte transformation microassay was used to study cell mediated immunity (CMI) in chickens following primary and secondary vaccination with inactivated oil emulsion infectious bronchitis (IB) vaccine and subsequent challenge with Massachusetts-41 (M-41). Humoral immunity was monitored for comparison, using the haemagglutination inhibition (HI) microassay. Positive stimulation indices (2 to 2.7 after primary and 2 to 4.8 after secondary vaccination) were lower and HI titres were higher than those previously reported following primary and secondary vaccination with live IB vaccines. The highest HI titres appeared in birds which had received the inactivated vaccine as a secondary vaccination. Challenge of vaccinated and revaccinated birds resulted in strong HI and weak CMI secondary responses. There was no correlation between CMI and HI antibody production. Monitoring egg production and clinical signs showed that a high level of protection against challenge resulted from revaccination with an inactivated oil adjuvant vaccine.