Sheep Red Blood Cell Antibody Research Articles

Effect of dietary supplemental vitamin C and betaine on the growth performance, humoral immunity, immune organ index, and antioxidant status of broilers under heat stress.

Heat stress (HS) has become one of the important factors affecting the development of animal husbandry. The purpose of this experiment was to investigate whether vitamin C (Vc) and betaine (Bet) improve immune organ index and humoral immunity by enhancing the antioxidant status of immune organs, thus protecting broilers from HS-induced injuries. A total of 200 28-day-old Ross 308 broilers were randomly assigned into 5 groups (n = 4 replicates/group, 10 broilers/replicate) which were reared at different ambient temperatures (24 ± 1°C or 33 ± 1°C). The control group fed basal diet, while high-temperature groups were either fed a basal diet (HS group) or a basal diet supplemented with 250-mg Vc/kg diet (HSVc group), 1000-mg Bet/kg diet (HSBet group), and 250-mg Vc plus 1000 mg Bet/kg diet (HSVcBet group), respectively. On day 42, growth performance, humoral immune function, immune organ index, and antioxidant capacity were measured. HS reduced the productive performance of broilers, antibody potency against the Newcastle disease virus (NDV) and sheep red blood cells (SRBC), indices of thymus and bursa, and antioxidant capacity of immune organs. Adding Vc alone or in combination with Bet improved performance, NDV and SRBC antibody potency, thymus and bursa indices, and antioxidant capacity of immune organs in heat-stressed broilers, with the most effective being combination. In summary, HS reduces the antioxidant capacity and immune organ development status of broiler immune organs. Vc and/or Bet can improve the development of immune organs and restore part of the production performance by regulating the antioxidant status of immune organs, among which the combined addition of Vc and Bet has the best effect.

Effect of fennel essential oil on performance, serum biochemistry, immunity, ileum morphology and microbial population, and meat quality of broiler chickens fed corn or wheat-based diet

ABSTRACT 1. The effect of Foeniculi aetheroleum essential oil (EO) on growth performance, nutrient utilisation, serum biochemistry, immune response, ileum morphology, microbial population and meat quality of broiler chickens fed a corn- or wheat-based diet were determined. 2. A total of 360 broiler chickens were arranged in a 2 × 2 factorial assay in a completely randomised design with six replicates and 15 birds per experimental unit. Birds were fed corn- or wheat-based diets supplemented with (200 mg/kg) or without fennel EO. 3. Birds fed wheat-based diets had lower BWG and FCR during grower period and lower FI during finisher period as compared to those fed corn-based diet (P < 0.05) whereas addition of fennel EO decreased chickens BWG during finisher period and EPEF, both in wheat or in corn-based diets. Dietary treatments had no effect on serum glucose, triglyceride, cholesterol, LDL-cholesterol, AST, ALT, ALP, and MDA concentrations (P < 0.05). 4. Antibody titres against avian influenza and sheep red blood cell antibody titres, crude protein and crude fat utilisation, villus height, crypt depth and epithelium thickness were not influenced by dietary treatments (P > 0.05). Inclusion of Fennel EO to the corn-based diet resulted in greater villus width and villus surface area while it reduced lamina propria thickness (P < 0.05). Fennel EO reduced ileal E. coli and Lactobacillus spp. populations (P < 0.05). Dietary treatments had no significant effect on meat pH, cooking loss, drip loss, crude protein, crude fat content and cholesterol concentration of breast and thigh meat, total phenolic and MDA concentrations, and breast meat sensory parameters (P > 0.05). 5. These results showed that addition of fennel EO to wheat-based diets had a negative effect on chicken growth performance variables and decreased gut E. coli populations. However, immunity, meat quality and nutrient utilisation were not affected by dietary treatments.

Effect of dietary L-tryptophan supplementation and‏ ‏light-emitting diodes on growth ‎and immune response of broilers ‎.

Light-emitting diodes (LEDs) lights are more energy-efficient and provide adequate illumination compared to compact fluorescent (CFL) lamps and incandescent light (ICD) bulbs. However, as new light sources, the LED lights may have a stress effect on broiler chickens. Thus, this study aimed to determine the effects of dietary L-tryptophan (Trp), as an anti-stress agent and different color temperatures of light-emitting diodes on immune responses and growth performance of male broiler chickens. Four hundred and eighty day-old Ross 308 male chicks were used from day 1 to 42. The chicks were randomly distributed into six treatment groups in a 2 × 3 factorial arrangement [0 or 1 g Trp per kg diet along with neutral-white (4286 K), warm-white (2990 K), and incandescent (2790 K) light bulbs] with four replicates of 20 chicks each. Results showed that dietary Trp and Trp×light interaction did not affect growth performance, immune responses, a total number of leukocytes, and different leukocytes count (heterophil, eosinophil, monocyte, and lymphocyte) of male broiler chickens. However, LEDs’ different color temperatures significantly affected the feed conversion ratio (FCR) and primary antibody of sheep red blood cell (SRBC). The FCR was the lowest in the warm-white light, and primary SRBC antibody titers of the chicks were the highest. In conclusion, although adding Trp to male broiler diets did not affect the growth performance and immune responses of chickens, the warm-white light improved the FCR and primary SRBC.

Evaluation of various levels of sweet almond meal as a source of protein on the production variables and immune response of broiler chickens.

This study was conducted to evaluate effects of a sweet almond meal (SAM) as a source of protein on performance and immune responses of broiler chickens. Treatments consisted of different levels of SAM (7%, 14%, 21% and 28% of diet) and control diet that was performed in a completely randomized design in 42 days. Body weight gain (BWG) and feed intake (FI) were recorded weekly. Carcass characteristics and blood variables were measured on the 42 day of age. Immune response to sheep red blood cell (SRBC) was assessed at d 35 and d 42 (7 days after each injection). White blood cell count was done at d 28. The results showed that chickens fed 28% of SAM had lowest FI during the experiment. During grower period and also whole period of experiment, BWG was highest in chickens that consumed 7% SAM. Feed conversion ratio (FCR) significantly increased in chickens fed 28% SAM compared to the other treatments during grower period and also whole period of the experiment. The relative weight of thigh and breast significantly decreased and the relative weight of GIT increased by increasing levels of SAM in the diet. The concentration of cholesterol and LDL significantly decreased in chickens that consumed SAM in the diet. However, the highest glucose and HDL concentration were observed in chickens fed 28% SAM in the diet. Treatments did not have a significant effect on the immune response of broilers (primary and secondary SRBC antibody titres, relative weights of spleen and bursa of fabricius and white blood cell count) (p > 0.05). The results of this study show that a diet supplemented with SAM at the level of 14%, due to the improved FCR and decreased blood cholesterol and LDL concentration, can be a good replacement for soybean meal in broiler chicken's nutrition.

Comparison of the Efficiency of BLUP and GBLUP in Genomic Prediction of Immune Traits in Chickens.

Simple SummaryWith the rapid development of the poultry industry, outbreaks of certain avian diseases such as avian influenza, Newcastle disease, and salmonellosis can cause severe loss to local economies. An effective method to avoid this problem may be developing resistant lines on the basis of immune response traits. In our study, when the number of genotyped reference animals was small, the traditional pedigree-based method (BLUP) was more efficient than the genetic linear unbiased prediction of genomes (GBLUP) method in predicting the genetic parameters of sheep red blood cell antibody titer (SRBC), the ratio of heterophils to lymphocytes (H/L), the spleen immune index (SII) and the spleen weight at 100 d (SW) in Beijing oil chickens.Poultry diseases pose a large threat to poultry production. Selection to improve immune traits is a feasible way to prevent and control avian diseases. The objective of this study was to investigate the efficiency of estimation of genetic parameters for antibody response to avian influenza virus (Ab-AIV), antibody response to Newcastle disease virus (Ab-NDV), sheep red blood cell antibody titer (SRBC), the ratio of heterophils to lymphocytes (H/L), immunoglobulin G (IgG), the spleen immune index (SII), thymus immune index (TII), thymus weight at 100 d (TW) and the spleen weight at 100 d (SW) in Beijing oil chickens, by using the best linear unbiased prediction (BLUP) method and genomic best linear unbiased prediction (GBLUP) method. The phenotypic data used in the two methods were the same and were from 519 individuals. With the BLUP model, Ab-AIV, Ab-NDV, SRBC, H/L, IgG, TII, and TW had low heritability ranging from 0.000 to 0.281, whereas SII and SW had high heritability of 0.631 and 0.573. With the GBLUP model, all individuals were genotyped with Illumina 60K SNP chips, and Ab-AIV, Ab-NDV, SRBC, H/L and IgG had low heritability ranging from 0.000 to 0.266, whereas SII, TII, TW and SW had moderate heritability ranging from 0.300 to 0.472. We compared the prediction accuracy obtained from BLUP and GBLUP through 50 time 5-fold cross-validation (CV), and the results indicated that BLUP provided a slightly higher accuracy of prediction than GBLUP in this population.

Modulating offspring responses: concerted effects of stress and immunogenic challenge in the parental generation.

The perception, processing and response to environmental challenges involves the activation of the immuno-neuroendocrine (INE) interplay. Concerted environmental challenges might induce trade-off when resource allocation to one trait occurs at the expense of another, also producing potential transgenerational effects in the offspring. We evaluated whether concerted challenges, in the form of an immune inoculum against inactivated Salmonella enteritidis (immune challenge, ICH) and a chronic heat stress (CHS) exposure on adult Japanese quail, modulate the INE responses of the parental generation and their offspring. Adults were inoculated and later exposed to a CHS along nine consecutive days. For the last 5 days of the CHS, eggs were collected for incubation. Chicks were identified according to their parental treatments and remained undisturbed. Induced inflammatory response, heterophil/lymphocyte (H/L) ratio and specific humoral response against sheep red blood cells (SRBC) were evaluated in both generations. Regardless of the ICH, stressed adults showed a reduced inflammatory response and an elevated H/L ratio compared with controls. In offspring, the inflammatory response was elevated and the specific SRBC antibody titres were diminished in those chicks prenatally exposed to CHS, regardless of the ICH. No differences were found in the H/L ratio of the offspring. Together, our results suggest that CHS exposure influences the INE interplay of adult quail, establishing trade-offs within their immune system. Moreover, CHS not only affected parental INE responses but also modulated their offspring INE responses, probably affecting their potential to respond to future challenges. The adaptability of the developmental programming of offspring would depend on the environment encountered.

Effects of medium-chain fatty acids on performance, carcass characteristics, blood biochemical parameters and immune response in Japanese quail

This study had the aim of evaluating the effects of medium-chain fatty acids (MCFA) on performance, carcass characteristics, some blood parameters and antibody titre against sheep red blood cells (SRBC) in quail.A total of 240 quail chicks were allotted to 4 treatments consisting of respectively 0, 1, 2 and 4 g/kg dietary MCFA.There were no significant differences in body weight, feed intake and feed conversion ratio among treatments at different stages of the experiment.MCFAs had no significant effect on breast, thigh, liver, spleen and bursa of Fabricius weight ratios. However, the relative weight of abdominal fat significantly decreased in quail receiving 0.2 and 0.4 MCFA as compared to other treatments.Concentrations of low-density lipoprotein-cholesterol (LDL), triglycerides and total cholesterol were decreased and high-density lipoprotein (HDL)-cholesterol was increased in quail chicks receiving MCFA compared with control quail chicks. The concentrations of SRBC antibody were not statistically different among treatments.It is concluded that MCFA significantly decreased LDL, triglycerides, cholesterol and abdominal fat and increased HDL in quail chicks.

Inhibition of CRAC with a human anti-ORAI1 monoclonal antibody inhibits T-cell-derived cytokine production but fails to inhibit a T-cell-dependent antibody response in the cynomolgus monkey

ORAI1 is the pore-forming component of calcium release-activated calcium (CRAC) channels. CRAC channels are the primary route for calcium ion (Ca2+) entry into T-cells following antigen stimulation. This Ca2+ entry induces proliferation and cytokine production through activation of calcineurin and the nuclear factor of activated T-cells (NFAT) transcription factor along with subsequent cytokine-related genes. It was hypothesized that the in vivo inhibition of T-cell function by blocking ORAI1 or calcineurin would lead to similar functional consequences. To test this hypothesis the activity of 2C1.1, a fully human anti-ORAI1 monoclonal antibody, and cyclosporin A (CsA) were tested in vivo for their suppressive effect on T-cell-derived cytokine production and a T-cell-dependent antibody response (TDAR) using sheep red blood cells (SRBC) in cynomolgus monkeys. Despite showing similar inhibition of ex vivo interleukin (IL)-2 production by stimulated T-cells, both molecules exhibited different pharmacologic effects on the SRBC antibody response. CsA blocked the development of SRBC-specific antibodies, while 2C1.1 failed to inhibit the antigen-specific antibody response. These surprising observations suggest that full inhibition of the CRAC channel is required to inhibit a functional immune response, consistent with findings from human patients with loss of function mutations in ORAI1.

English

In this study, the effect of methanol extract of whole aerial parts of&nbsp;Phyllantus niruri&nbsp;on some specific and non-specific immune response was investigated. The effects of&nbsp;P. niruri&nbsp;on&nbsp;in vivo&nbsp;leucocyte mobilization, delayed type hypersensitivity (DTHR) response, and humoral antibody (HA) response were determined in rats. Acute toxicity profile of&nbsp;P. niruri&nbsp;was evaluated in mice. The Agar induced&nbsp;in vivo&nbsp;leucocytes mobilization into the rats peritoneal fluid was (P&lt;0.05) increased by&nbsp;P. niruri&nbsp;N (200 and 400 mg/kg) in a dose related manner. The total leucocytes count was higher in the extract treated group than the control group. Polymorphonuclear neutrophils (PMNS) were more mobilized than the lymphocytes.&nbsp;P. niruri&nbsp;at 100, 200 and 400 mg/kg body weight produced significant (P&lt;0.05) inhibition of DTH response in rat by 30.55, 66.67 and 44.44%, respectively with 200 mg/kg being most significant. The primary and secondary sheep red blood cell antibody titres were significantly elevated when compared with the control group.&nbsp;P. niruri&nbsp;administered orally showed no death or signs of acute intoxication at doses up to 5000 mg/kg after 24 h of observation. The result of this study showed that the methanol extract of&nbsp;P. niruri&nbsp;whole plant possess immunomodulatory activities and warrant further investigation to determine the specific constituent(s) of the plant responsible for this property. Key words:&nbsp;Phyllantus niruri, leucocyte mobilization, delayed type hypersensitivity (DTHR), humoral antibody titre, immunomodulation.&nbsp

The effects of different levels of Aloe vera gel on ileum microflora population and immune response in broilers: a comparison to antibiotic effects

The purpose of the present research is to study the effects of different levels of Aloe vera gel on microflora population, humoral and cellular immune response, and relative weight of lymphoid organs compared to the effects brought about by antibiotic. The groups included the control group (basal diet) as well as three groups with different levels of Aloe vera gel (added to basal diet at 1.5%, 2% and 2.5%), and finally a group with basal diet supplemented by 15 ppm virginiamycin antibiotic. Regarding ileum microflora, the increase in Aloe vera gel in the feed resulted in significant reduction in the number of E. coli colonies and significant increase in the number of Lactobacillus colonies compared to the control and antibiotic groups. As far as humoral immunity is concerned, Newcastle disease virus antibody titre on the 24th and 38th day was the highest in 2.5% and 2% Aloe vera gel groups, respectively. In addition, sheep red blood cells antibody titre reached its highest level in the 2.5% Aloe vera gel group on the days 24, 28, 34 and 38. The differences among the groups regarding sheep red blood cells antibody titre were significant on the days 24, 28 and 34, while no significant differences were observed on the 38th day. Regarding the cellular immunity, the highest response was obtained by injecting phytohemagglutinin-P and the highest relative weight of spleen and bursa of Fabricius was found in the 2.5% Aloe vera gel group. The findings of the study suggest reduction in number of E. coli colonies and increase in number of Lactobacillus colonies as a result of increased Aloe vera gel in the feed. Furthermore, the 2.5% Aloe vera gel group resulted in significantly higher levels of humoral and cellular immunity, as well as relatively greater weight of lymphoid organs, which suggests that Aloe vera gel can be a proper replacement for the virginiamycin antibiotic.

Evaluation of Oyster Mushroom (&lt;i&gt;Pleurotus Ostreatus&lt;/i&gt;) as a Biological Growth Promoter on Performance, Humoral Immunity, and Blood Characteristics of Broiler Chicks

This study was conducted to determine the impacts of two levels of oyster mushroom (Pleurotus ostreatus) powder on productive and carcass traits, humoral immune responses, and blood characteristics of Ross 308 male broiler chicks reared to 42 d of age in comparison with a prebiotic supplement. Two hundred and forty, day-old male broiler chicks (Ross 308) were randomly assigned to one of four treatments with four replicates of 15 chicks based on a completely randomized design. The dietary treatments consisted of the basal diet as control, prebiotic group receiving 1 g/kg A-Max (Mannan-oligosaccharides), 10, and 20 g/kg oyster mushroom powder added to the basal diet. The obtained results showed that inclusion of 20 g/kg mushroom powder significantly improved body weight over the starter and grower (P<0.05) while feed efficiency was improved only over the starter (P<0.05) period compared to the control group. Considering the entire experimental period, (1-42 d) birds receiving prebiotic supplemented diets exhibited the highest body weight and lowest feed conversion ratio relative to the other treatments (P<0.05). Carcass yield and internal organs relative weights were not influenced by dietary treatments, but prebiotic supplementation significantly (P<0.05) decreased abdominal fat pad compared to the control group. Newcastle, influenza and sheep red blood cell antibody responses of chicks did not differ significantly at either level of inclusion of supplements. Chicks fed supplemented diets had the lowest serum triglyceride concentration at 42 day (P<0.05) compared to the control chicks, but other biochemical and hematological values tested including protein, albumin, globulin, high-density lipoprotein, low-density lipoprotein, and total cholesterol, red blood cell, white blood cell, hemoglobin and hematocrit were not markedly affected by treatments. In conclusion the obtained results indicated that oyster mushroom powder at an inclusion level of 20 g/kg of diet had favorable effects on performance criteria of chicks reared to 28 day of age while, prebiotic supplementation revealed its beneficial impact on chicks productive traits at slaughter age, besides reducing carcass abdominal fat and serum triglyceride concentration at 42 day.

Immunostimulatory and protective effects of Aloe vera against coccidiosis in industrial broiler chickens

This paper reports the immunostimulatory and protective effects of Aloe vera extracts (aqueous and ethanolic) against coccidiosis in industrial broiler chickens. The study was divided into two experiments. Experiment-I was conducted for the evaluation of immunostimulatory activity of A. vera and experiment-II demonstrated the protective efficacy of A. vera extracts against coccidiosis in chickens. Results of the experiment-I revealed significantly higher (p<0.05) lymphoproliferative responses in chickens administered with ethanolic extract of A. vera as compared to those administered with aqueous extract and control group. Microplate haemagglutination assay for humoral response on day 7th and 14th post primary and secondary injections of sheep red blood cells (SRBCs) revealed significantly higher (p<0.05) anti SRBC antibody (total Igs, IgG and IgM) titers in chickens of experimental groups as compared to the control group. None of the extracts, however, demonstrated significant effects on the development of lymphoid organs. Results of experiment-II revealed maximum protection (60%) in chickens administered with aqueous Aloe extract as compared to the ethanolic extract administered chickens (45%). Mean oocysts per gram of droppings in the control group was significantly higher (p<0.05) as compared to the chickens in both the experimental groups. Chickens administered with aqueous Aloe extract showed a minimal mean lesion score (2.3) followed by those administered with ethanolic Aloe extract (2.6) and control chickens (3.05) for caeca, and a similar pattern was observed for intestinal lesion scoring. Further, significantly higher weight gains and antibody titers (p<0.05) were observed in chickens administered with A. vera extracts as compared to those in the control group. It was concluded that A. vera may be a potential and valuable candidate to stimulate the immune responses and can be used successfully as an immunotherapeutic agent against coccidiosis in industrial broiler chickens.

Immunostimulatory and protective effects of Aloe vera components against coccidiosis in broilers

Present study reports immunostimulatory effect of Aloe vera L. extracts in chickens and their protection against coccidiosis. Study was divided into two experiments. Experiment-I was conducted for evaluation of immunostimulatory activity of Aloe vera extracts and experiment-II for protective efficacy against coccidiosis. Results of experiment-I revealed significantly higher (P<0.05) lymphoproliferative responses in chickens administered with ethanolic extract as compared to chickens administered aqueous extract and control group. Microplate haemagglutination assay for humoral response on day 7th and 14th post primary and secondary injections of sheep red blood cells (SRBC) revealed significantly higher (P<0.05) anti SRBC antibody (total Ig, IgG and IgM) titers in experimental groups as compared to control; although both the Aloe vera extracts showed no significant effects on the development of lymphoid organs. Results of experiment-II revealed maximum percent protection (60%) in chickens administered with aqueous extract as compared to ethanolic extract administered chickens (45%). Mean oocysts per gram of droppings in control group was significantly higher (P<0.05) as compared to chickens in both experimental groups. Chickens administered with aqueous extract (40%) showed severe lesions (3.0–4.0); whereas 55 and 75 percent severe lesions were recorded in ethanolic extract administered and control chickens, respectively. Daily weight gains from day 3rd-12th post-challenge were significantly higher (P<0.05) in chickens administered with aqueous extract as compared to those administered with ethanolic extract and control. It was concluded that Aloe vera may be potential and valuable candidate to stimulate the immune responses and can be used successfully in immunosuppressive diseases like coccidiosis.

Do standard measures of immunocompetence reflect parasite resistance? The case of Greenfinch coccidiosis

Summary Much research in evolutionary animal ecology is currently focused on issues related to parasite‐mediated selection. Because of difficulties in estimation of actual parasite resistance, researchers often rely on surrogate measures of immunocompetence, such as the magnitude of immune responses to artificial antigens, assuming that these measures correlate with individuals’ ability to resist disease. This assumption was tested in the Greenfinch (Carduelis chloris L.) coccidiosis model by measuring the association between parasite resistance and two standard assays of immune function – a swelling response to phytohaemagglutinin (PHA) and antibody production against sheep red blood cells (SRBC). Before performing immune challenge assays, host resistance to the intestinal parasite Isospora lacazei (Labbe) was assessed on the basis of individual infection intensities and responses to challenge infection with alien parasite strains. Increases in infection intensities after inoculation of birds with novel parasite strains correlated positively with magnitude of swelling response to PHA injection. Thus, intense parasite multiplication in the host's digestive tract resulted in the enhancement of the host's cell‐mediated immune function. Among birds that were vulnerable to novel infections, no correlations emerged between infection intensities, SRBC antibody titres and condition indices. Among non‐vulnerable hosts (whose infection intensities did not increase after experimental reinfection), SRBC antibody titres correlated negatively with infection intensities and positively with indices of nutritional condition. Hence, high SRBC antibody titres reflected good nutritional status and superior resistance to an important parasite species in a subsample of studied Greenfinches. Altogether, our results exemplify the diversity of outcomes when the host's immune system is simultaneously challenged by natural enemies and artificial antigens, and call for the cautious interpretation of the results of standard immune tests in the context of parasite resistance.

Long-term effects of early life L-arginine supplementation on growth performance, lymphoid organs and immune responses in Leghorn-type chickens

1. The effects of a short-term dietary arginine supplementation after hatching on subsequent growth and the immune system were assessed in growing male Leghorn-type chickens. 2. An arginine-deficient basal diet (6·7 g/kg) supplemented with 0 (control), 2·7 (LA) or 5·4 (HA) g L-arginine/kg, was offered ad libitum to 1-d-old male ISA Brown chicks for 4 weeks, then all birds were offered ad libitum a commercial pullet grower feed (8·9 g arginine/kg) for another 8 weeks. 3. Supplemented birds had higher growth rates and feed intake than control birds during the 4-week supplementation period, but these effects did not persist into the subsequent periods. 4. When the supplementation ceased at week 4, no differences in lymphoid organ weights relative to body weight (BW), primary serum antibody levels against sheep red blood cells (SRBC) or cutaneous reactivity of toe webs to phytohaemagglutinin (PHA) were detected. 5. LA-fed birds had lower immunoglobulin (Ig) G levels against bovine serum albumin (BSA) than the control at week 4, but this effect did not persist at weeks 8 and 12. 6. No difference in anti-BSA IgM levels was detected among birds at week 4; at week 12, however, the LA-fed birds had a significantly higher anti-BSA IgM level than the control. 7. An increased anti-SRBC antibody level and a reduced relative bursa weight in HA-fed birds were evident at week 8, without any prior effects. 8. It is concluded that short-term supplementary L-arginine had minimal effects on immunity, but some enhancement of SRBC antibody responses in later stages of growth was observed with previous L-arginine administration.

The modulator role of the hypothalamic paraventricular nucleus on immune responsiveness

Role of the paraventricular nucleus of the hypothalamus (PVH) upon immune modulation was studied by either mechanically destroying the PVH (PVHL) or by isolating the PVH (PVHI) with a knife-cut. PVHL or PVHI manipulations induced significant leukopenia characterized by a decrease in the number of neutrophils and lymphocytes two weeks post surgery. The numbers of circulating monocytes and eosinophils were not affected by PVH interventions. In addition, PVHL and PVHI were also associated with a reduction, relative to controls, in the phagocytosis by neutrophils and an increase in blastic transformation of T lymphocytes induced by phytohemagglutinin-M (PHA-M). Antibody titers rose against sheep red blood cells (SRBC) after either PVHL or PVHI were reduced. The magnitude of the SRBC antibody reduction after PVH manipulations was similar to that observed in rats that received a peripheral chemical sympathectomy two hrs prior immunization. Comparison of thyroid hormones blood levels two weeks after PVHL or PVHI revealed significant reductions in comparison with sham-operated group (SO), whereas blood corticosterone was not significantly altered. In summary, we provide evidence that lesion or isolation of the PVH selectively reduces circulating white blood cells and the primary immune response, while it enhances the cell-mediated immune function. Taken together our data showed that PVH modulates immune functions by altering both the peripheral sympathetic tone and thyroid hormone secretion.

Diet and Humoral Responsiveness of Lines of Chickens Divergently Selected for Antibody Response to Sheep Red Blood Cells

Growth and humoral immune response were studied in lines of white leghorn chickens selected for high (HA) or low (LA) 5-day antibody titers to an i.v. inoculation with 0.1 ml of a 0.25% suspension of sheep red blood cells (SRBC) antigen(s). Chicks were fed either a high (E) or low (A) nutrient density diet from hatch onward. Chicks from each line-diet subclass were inoculated i.v. with 0.1 ml of either 0.25% or 2.50% suspension of SRBC at either 7, 14, 21, or 28 days of age. Antibody titers were measured 5, 10, and 20 days after inoculation. LA chicks were heavier than HA chicks at 7 days of age and thereafter. Chicks fed diet E were heavier than those fed diet A. Feed efficiency was influenced by diet (E > A) at 21 and 28 days of age and line (LA > HA) at 28 days of age. In all but one case, antibody titers to SRBC were higher in HA than LA chicks. Also, the frequency of nonresponders of chicks inoculated with SRBC at 7 days of age was higher for LA than HA chicks. The higher dosage elicited greater 5-day antibody responses in LA but not in HA chicks inoculated at 28 days of age. Dietary effects on SRBC antibody were generally unimportant except for occasional interactions of dosage and line.

Impact of Alternate-Day Feeding Cycles on Immune and Antibacterial Responses of White Leghorn Chicks

White Leghorn cockerels helped measure the effect of number of cycles of alternate-day feeding (food restriction of 24 hr fast and 24 hr full-feed per cycle) on immune and antibacterial responses assessed after inoculation with E. coli or sheep red blood cell (SRBC) antigen. Chicks fed ad libitum had a more severe response to E. coli challenge than those on alternate-day feeding regimens. SRBC antibody titers were highest in chicks exposed to several cycles of alternate-day feeding and least for the 1-day fasted chicks.

粘膜免疫における口蓋扁桃への抗原投与の有効性

Our former report showed that palatine tonsil effectively incorporated exogenous foreign substances instilled at the surface of palatine tonsil. It is not clear whether antigen specific secretory IgA can be induced by the instillation. Sheep red blood cells (SRBC) were instilled at the palatine tonsil every three days as antigen and the appearance of specific secretory IgA in saliva was examined. In control experiment, nasal administration and intragastric one, which have been shown to induce secretory antibody in saliva, were done. Anti SRBC antibody in saliva from tonsillar instillation group was detected in the second week and the agglutination titer reached a maximum in the 6th week after the instillation. The titers in their maxima in tonsillar instillation group and nasal administration group were higher than that in intragastric administration group, 16 times (p<0.01, n=7) and 4 times (p<0.01, n=7), respectively. In tonsillar instillation group, the number of specific antibody producing cells per 10^5 lymphocytes was the highest in parotid glands among the lymphoid tissues as retropharyngeal lymph nodes, nasal mucosa, mesenteric lymph nodes, Peyer's patches, cervical lymph nodes, palatine tonsil and spleen. In nasal administration group, the number in nasal mucosa was the highest. The results showed that tonsillar instillation was the most effective administrating method to induce specific IgA in saliva among the three methods.

Comparison of ELISA and Plaque-Forming Cell Assays for Measuring the Humoral Immune Response to SRBC in Rats and Mice Treated with Benzo[a]pyrene or Cyclophosphamide

Comparison of ELISA and Plaque-Forming Cell Assays for Measuring the Humoral Immune Response to SRBC in Rats and Mice Treated with Benzo[a]pyrene or Cyclophosphamide. TEMPLE, L., KAWABATA, T. T., MUNSON, A. E., AND WHITE, K. L., JR. (1993). Fundam. Appl. Toxicol. 21, 412–419. The humoral immune response against sheep red blood cells (SRBC) is one of the most sensitive and frequently used endpoints in evaluating the immunotoxicity of drugs and chemicals in experimental animals. Currently, most immunotoxicology studies measure the SRBC IgM antibody response by quantitating the number of SRBC-specific IgM antibody-forming cells using the hemolytic plaque assay. On the other hand, measurement of serum SRBC-specific IgM could be an easier, more cost effective endpoint in evaluating the SRBC antibody response in rodents. A validated method to measure SRBC-specific IgM, however, has not been developed. Thus, the objectives of the studies presented were to develop and validate an enzyme-linked immunosorbent assay (ELISA) for SRBC-specific IgM. Hemoglobin-free, detergent-solubilized membrane preparations were chosen as antigen for the ELISA. Various sources of SRBC were found to be equally useful, and as little as 0.1 μg of protein per well was optimal. Kinetic studies of the IgM response showed the peak day to be on Day 5 (mice) and Day 6 (rats). To validate the usefulness of the method for immunotoxicologic studies, serum SRBC-specific IgM levels and number of SRBC-specific plaque-forming cells were compared in rats and mice treated with two well-characterized immunosuppressive agents: benzo[a]pyrene and cyclophosphamide. Administration of these chemicals was found to produce very similar dose-dependent decreases in serum SRBC IgM and IgM-specific plaque-forming cells. These two endpoints were equally sensitive to the effects of the immunosuppressive drugs. Based on the present findings and the sensitivity, simplicity, and potential for automation of the ELISA for SRBC-specific IgM, the ELISA could potentially replace the plaque assay as the first step in testing for potential immunotoxic chemicals.