Decreased mitogen responsiveness and elevated tumor necrosis factor production in cats shortly after feline immunodeficiency virus infection.

We present the results of an investigation into the effects of feline immunodeficiency virus (FIV) infection on the response to mitogens and cytokine production in the first month of infection. We were able to demonstrate a depression of response of peripheral blood mononuclear cells to the mitogens concanavalin A, phytohaemagglutinin and pokeweed mitogen, with the response to pokeweed mitogen being most severely affected. The response of the cells of the spleen were affected by 10 days post infection and these could not be augmented by the addition of exogenous interleukin-2 (IL-2). The response of mesenteric lymph node cells was not affected until 20 days post infection and this could be partially restored by the addition of exogenous IL-2. IL-2 production was unaffected in peripheral blood mononuclear cells, slightly depressed in mesenteric lymph node cells and slightly elevated in spleen cells. Tumor necrosis factor levels were significantly elevated with respect to controls within 10 days of infection. These studies suggest that there are a number of changes in the immune response of FIV infected cats early in infection and this may determine the subsequent outcome of the infection.     

Alteration of helper T-cell related cytokine production in splenocytes during Trichinella spiralis infection

Infection by Trichinella spiralis takes place in two distinct phases: one is the intestinal phase and the other is the muscle phase. To evaluate alterations in cytokine production during a T. spiralis infection, we periodically assessed the cytokine production of splenocytes in mice after infection (AI). The levels of Th2-related cytokines immediately increased after the initiation of T. spiralis larval intestinal invasion (1 week AI). These early elevations in the Th2 response might be associated with the innate immune responses of intestine epithelial cells against T. spiralis larval invasion. IL-4 and IL-13 levels reached a peak prior to the initiation of nurse cell formation (2 weeks AI). Additionally, all Th17-related cytokines, except for IL-17, increased slightly until 2 weeks AI. However, expression levels for all of the Th2 and Th17-related cytokines began to decrease after the initiation of nurse cell formation and reached basal levels at 4 weeks AI, except for IL-5. At the same time, the CD4(+)CD25(+)Foxp3(+) T (regulatory T, T(reg)) cell population increased significantly in the spleen. Additionally, the number of cells in the peripheral lymph nodes increased. In conclusion, T. spiralis larva intestinal invasion induced the production of Th2 and Th17 cell-related cytokines, and the cytokines decreased with T(reg) cell-related cytokine.     

Expression of interleukin 4, interleukin 4 splice variants and interferon gamma mRNA in calves experimentally infected with Fasciola hepatica

Interleukin 4 (IL-4) is expected to play a dominant role in the development of T helper (Th) 2 cells. Th2 immune responses with expression of relatively large amounts of interleukin 4 (IL-4) but little interferon gamma (IFN-gamma) are characteristic for chronic helminth infections. But no information is available about IL4 expression during early Fasciola hepatica (F. hepatica) infections in cattle. Therefore, we investigated F. hepatica specific IL-4 and IFN-gamma mRNA expression in peripheral blood mononuclear cells (PBMCs) from calves experimentally infected with F. hepatica. Cells were collected prior to infection and on post-inoculation days (PIDs) 10, 28 and 70. Interestingly, PBMCs responded to stimulation with F. hepatica secretory-excretory products (FhSEP) already on PID 10 and expressed high amounts of IL-4 but not of IFN-gamma mRNA suggesting that F. hepatica induced a Th2 biased early immune response which was not restricted to the site of infection. Later in infection IL-4 mRNA expression decreased whereas IFN-gamma mRNA expression increased slightly. Isolated lymph node cells (LNCs) stimulated with FhSEP and, even more importantly, non-stimulated LN tissue samples indicated highly polarized Th2 type immune responses in the draining (hepatic) lymph node, but not in the retropharyngeal lymph node. During preliminary experiments, two splice variants of bovine IL-4 mRNA, boIL-4delta2 and boIL-4delta3, were detected. Since a human IL-4delta2 was assumed to act as competitive inhibitor of IL-4, it was important to know whether expression of these splice variants of bovine IL-4 have a regulatory function during an immune response to infection with F. hepatica. Indeed, IL-4 splice variants could be detected in a number of samples, but quantitative analysis did not yield any clue to their function. Therefore, the significance of bovine IL-4 splice variants remains to be determined.     

Infection of normal C3H/HeN mice with Taenia saginata asiatica oncospheres

Normal C3H/HeN female mice were used to develop an animal model of Taenia saginata asiatica oncosphere infection. The host cellular immune response in this model was analyzed by a cytokine enzyme-linked immunosorbent assay (cytokine ELISA) and flow cytometry. Tumor-like cysts containing cysticerci were recovered from the inoculation sites of female mice 7 weeks postinfection with the T. saginata asiatica oncospheres. A sharp increase and sustained elevation in the ability of spleen cells to produce interferon-γ and interleukin (IL)-2 revealed that cellular immunity played an important role during the infection. An immediate increase in the levels of IL-6 at 1 week postinfection indicated the induction of a local acute inflammatory response. However, no significant change in the levels of IL-10 indicated that Th2 cells were not involved in this immune response. The patterns of cell distribution revealed by flow cytometry also supported the same finding. These results suggested that Th1 cells played a major role in the immune response in C3H/HeN mice during the early stages of the oncosphere infection and that the Th2 response was not induced during the stage of cysticercus formation.     

Systemic cytokine profile in feeder pigs suffering from natural postweaning multisystemic wasting syndrome (PMWS) as determined by semiquantitative RT-PCR and flow cytometric intracellular cytokine detection

Postweaning multisystemic wasting syndrome (PMWS) is an economically important disease in pigs caused by porcine circovirus type 2 (PCV2). Development of this disease is presumably associated with an impairment of the immune system. We, therefore, investigated the systemic expression of relevant cytokines (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, TNF-alpha, IFN-gamma) and IL-2Ralpha at mRNA (semiquantitative RT-PCR) and at protein level (flow cytometric intracellular cytokine detection after short-time stimulation of peripheral blood mononuclear cells) in 10 feeder pigs aged 14 weeks suffering from natural PMWS and in 10 clinically healthy pen-mates. Hematological examination revealed a significant (p < 0.001) relative lymphopenia in the diseased animals when compared to reference pigs. IL-1alpha and IL-10 mRNA levels were notably increased in the affected pigs, whereas IL-2 and IL-2Ralpha (CD25) mRNA levels tended to be down-regulated. IL-8, TNF-alpha and IFN-gamma mRNA expressions appeared to be slightly increased. Intracellular cytokine levels as measured by flow cytometry revealed an increase of IL-1beta, IL-2, and IL-6, whereas IL-12 and TNF-alpha expressions were not affected. IFN-gamma was slightly decreased in the diseased animals. In conclusion, despite the assumption, that the cellular immune response to PMWS as a virus-induced disease should be characterized by either a Th1 driven cytokine profile or a cytokine profile indicative of T cell immunosuppression, our results did not support that hypothesis. Nevertheless, data from intracellular cytokine detection suggest an even increased percentage of the remaining lymphocytes capable to produce IL-2 upon in vitro stimulation, which is in contrast to the slightly diminished IL-2 mRNA levels reflecting the in vivo situation at least at the mRNA level.     

Effect of bovine colostrum supplementation on cytokine mRNA expression in weaned piglets

The aim of this study was to evaluate the influence of bovine colostrum supplementation on the immune Th1/Th2 response in weaned piglets. After weaning at 21 d, 3 groups of 7 piglets were fed ad libitum with a starter diet and received daily 0, 1 or 5 g of spray-dried bovine colostrum. Spleen and gut-associated lymphoid tissues (GALT): ileal Peyer's patch (iPP), jejunum wall (JW) and mesenteric lymph node (MLN)) biopsies were collected on each piglet after 3 wk of treatment and analysed for their cytokine mRNA expression (IL-2, IL-4, IL-10, IL-12 and IFNγ) by RT-PCR. The supplementation with bovine colostrum induced an increase (P < 0.05) in IL-12 in the JW, in IL-2, IL-10 and IL-12 in the MLN and in IL-4, IL-10 and IL-12 in the iPP. In the latter, bovine colostrum also decreased IFN-γ production (P < 0.01). Finally, no effect of the treatments was recorded in the spleen. These results suggest an immunomodulatory effect of bovine colostrum on the GALT, which responded by producing at different levels both Th1 pro-inflammatory cytokines (IL-2, IFN-γ and IL-12) and Th2 anti-inflammatory cytokines (IL-4 and IL-10). This Th1/Th2 bipolar response protects the weaned piglets from both allergic (food) and infectious (pathogens) diseases.     

冷应激对湖羊血清因子及热休克蛋白70 mRNA表达的影响

为研究冷应激对湖羊免疫系统及热休克蛋白70(heat stress proteins 70,Hsp70)的影响,试验分别采用实时荧光定量PCR和ELISA方法检测冷应激前后湖羊肝脏、肺脏、脾脏、淋巴结组织中Hsp70mRNA表达量及血清中白细胞介素-2(IL-2)、白细胞介素-4(IL-4)浓度。结果显示,与冷应激前相比,冷应激后湖羊肝脏、肺脏及脾脏组织中Hsp70mRNA表达量均极显著增加(P0.01),其中肝脏的表达量尤为显著;冷应激后湖羊血清中IL-2、IL-4的浓度均呈下降趋势,其中IL-4浓度下降尤为显著(P0.01)。结果表明,冷应激条件下湖羊各组织中Hsp70mRNA表达增强,可提高动物机体的自我保护机能,增强对外界不良刺激的抵抗力,但细胞因子IL-2和IL-4的浓度下降,表明冷应激抑制机体免疫系统。     

Swine infection with Trichinella spiralis: Comparative analysis of the mucosal intestinal and systemic immune responses

The immune protective response developed by swine against Trichinella spiralis is not yet fully understood, particularly at the mucosal level. This study aimed to characterise intestinal immunity to T. spiralis by comparison with the systemic response in specifically pathogen-free pigs. For this purpose, the kinetics of cytokine and antibody production were assessed in the intestinal mucosa and serum of swine infected with T. spiralis for up to 60 days post-infection (dpi). An ex vivo model of jejunum mucosa culture was used to collect the supernatant as a source of antibodies (Abs). Mucosal antibodies were observed by Western blot from 15 dpi, while serum antibodies were expressed from 20 dpi. Both sources of antibodies initially recognized a 110 kDa protein, followed by the identification of 35, 43/46 and 55/59 kDa proteins. IgG1 and IgA antibodies were strongly expressed within the mucosa. The expression levels of Type 1 (IFN-gamma, IL-12), Type 2 (IL-4, IL-6), pro-inflammatory (TNF-alpha) and regulatory (IL-10, TGF-beta) cytokines were assessed by RT-PCR in the intestinal mucosa and spleen. Both IL-10 and IFN-gamma mRNA levels were increased in mucosa, whereas IL-6 and IL-12 mRNA were expressed in spleen. Taken together, these results demonstrated a mixed Type 1/Type 2 profile, the Type 2 profile being dominant in the mucosa.     

Early hepatic immune response in rats infected with Fasciola hepatica

We investigated the phenotype of the T cells (CD4+ and CD8+) that produced Th1 (IFN-gamma) and Th2 cytokines (IL-4 and IL-10) during the firsttwo weeks of experimental fasciolosis in rats. We also followed the kinetics of the cytokine and proliferative responses of hepatic mononuclear cells (HMNC) over the same period. We found that HMNC were more numerous in the infected animals than in the controls. The percentage of CD4+ cells increased significantly after infection, whereas the percentage of CD8+ cells did not change. Moreover, the frequency of the cells producing (CP) cytokine changed after infection. The frequency of CP IFN-gamma on 7 days postinfection (pi) was similar to that in control animals. However, the frequency of CP IFN-gamma was clearly lower on day 14 pi, whereas the frequency of CP IL-4 and CP IL-10 had increased. The CP IL-10-were mostly CD4+. Mitogenic stimulation (phorbol myristate acetate/ionomycin) of HMNC led to an increase in the amounts of the Th2 cytokines in the supernatant on days 7 and 14 pi, with the increase more pronounced on day 14. In contrast, IFN-gamma levels also increased by day 7 pi but then decreased to below control levels by day 14. In addition, HMNC proliferation in response to mitogen followed a similar pattern to IFN-gamma production. These findings suggested that, during the first 2 weeks of infection, F hepatica induced a transient ThO cytokine profile followed by downregulation of the cellular response and the induction of a Th2 cytokine profile.     

Profiling pro-inflammatory cytokine and chemokine mRNA expression levels as a novel method for selection of increased innate immune responsiveness

Previous studies using F1 reciprocal crosses and two parental lines of broilers show the sire is instrumental in determining the in vitro leukocyte function and cytokine/chemokine profile. Since the innate immune response is the primary means young chickens have to protect themselves, we hypothesize utilizing a novel genomics approach to select sires based on an elevated pro-inflammatory cytokine and chemokine profile. By identifying sires with increased pro-inflammatory cytokine (interleukin [IL]-1beta and IL-6) and chemokine (CXCLi2 and CCLi2) mRNA expression levels, we expect the progeny will also have elevated profiles. We characterized the pro-inflammatory cytokine and chemokine profile of 119 sires using quantitative real-time RT-PCR (qRT-PCR) and identified two populations with inherently high and low mRNA expression levels of IL-1beta, IL-6, CXCLi2, and CCLi2. Select high and low sires were then used to produce progeny for the second phase of the trial. Blood samples were collected from 214 progeny and the cytokine and chemokine mRNA expression levels determined. Progeny from high sires had significantly (P相似文献   

mRNA profile of Nellore calves after primary infection with Haemonchus placei

Haemonchus parasites are responsible for many losses in animal production. However, few studies are available, especially of zebu cattle. In this study, we investigated mRNA differences of immune response genes in na?ve Nellore calves infected with Haemonchus placei, relating these differences to patterns of cellular infiltrate. Calves were infected with 15,000 H. placei L3 larvae and after 7 days lymph node and abomasum tissues were collected. IL-2, IL-4, IL-8, IL-12, IL-13, IFN-γ, MCP-1, lysozyme, pepsinogen and TNF-α genes were evaluated by qPCR. Mast cells, eosinophils and globular leukocytes were counted by abomasum histology. In the infected group, IL-4, IL-13 and TNF-α were up-regulated in the abomasal lymph node. In the abomasum, IL-13 increased and TNF-α was down-regulated (p<0.05). No differences were detected for mast cells and eosinophil counts in abomasal tissue (p>0.05). We conclude that for this infection time, there was Th2 polarization but that cellular infiltrate in abomasal tissue takes longer to develop.     

Tissue-specific expression of the NOD-like receptor protein 3 in BALB/c mice

Activation of the innate immune system requires recognition of pathogen-associated molecular patterns, such as NOD-like receptors. The NOD-like receptor protein 3 (NLRP3) inflammasome is involved in induction of the pro-inflammatory cytokine, IL-1β, and subsequent inflammatory responses. NLRP3 inflammasome plays important roles in the inflammatory and innate immune responses associated with autoimmune/inflammatory syndrome. However, analysis of the tissue distribution and expression profiles in BALB/c mice is still incomplete. In this study, we investigated the tissue distribution and expression pattern of NLRP3 in BALB/c mice to further elucidate its function in innate immunity in this commonly used laboratory animal model. NLRP3 mRNA expression levels and tissue distribution of the protein were investigated by real-time quantitative PCR and immunohistochemical analyses, respectively. NLRP3 mRNA expression was higher in the kidney and inguinal lymph nodes than in other tissues. Cytoplasmic expression of NLRP3 was detected in the epithelial reticular cells of the spleen and thymus, lymphocytes in the inguinal lymph nodes, cardiac muscle cells, cerebral cortex neurons, alveolar macrophages, renal tubule cells and liver sinusoidal endothelial cells. The results of this study will assist investigators in interpreting site-specific functions and roles of NLRP3 in inflammatory responses.