猪链球菌2型强弱毒株对BALB/c小鼠肠道菌群影响的差异

目的 旨在探究猪链球菌2型强弱毒株对BALB/c小鼠肠道菌群的影响差异.方法 本研究随机将3周龄的雌性BALB/c小鼠分为3组,即空白对照组、猪链球菌2型强毒株SS2-1感染组和弱毒株HA0609感染组.采用Illumina Miseq测序技术,测定了小鼠结肠粪便样品中微生物16S rRNA V3-4区序列,并对其微生...     

Cross‐protective efficacy from a immunogen firstly identified in Leishmania infantum against tegumentary leishmaniasis

Experimental vaccine candidates have been evaluated to prevent leishmaniasis, but no commercial vaccine has been proved to be effective against more than one parasite species. LiHyT is a Leishmania‐specific protein that was firstly identified as protective against Leishmania infantum. In this study, LiHyT was evaluated as a vaccine to against two Leishmania species causing tegumentary leishmaniasis (TL): Leishmania major and Leishmania braziliensis. BALB/c mice were immunized with rLiHyT plus saponin and lately challenged with promastigotes of the two parasite species. The immune response generated was evaluated before and 10 weeks after infection, as well as the parasite burden at this time after infection. The vaccination induced a Th1 response, which was characterized by the production of IFN‐γ, IL‐12 and GM‐CSF, as well as by high levels of IgG2a antibodies, after in vitro stimulation using both the protein and parasite extracts. After challenge, vaccinated mice showed significant reductions in their infected footpads, as well as in the parasite burden in the tissue and organs evaluated, when compared to the control groups. The anti‐Leishmania Th1 response was maintained after infection, being the IFN‐γ production based mainly on CD4⁺ T cells. We described one conserved Leishmania‐specific protein that could compose a pan‐Leishmania vaccine.     

The role of TGF-beta in mice infected with Heligmosomoides polygyrus

Hyporesponsiveness induced by Heligmosomoides polygyrus was quantified and the relationship between TGF-beta and inflammation was identified in BALB/c mice. The immune response and pathological changes modified by neutralization of TGF-beta were characterized in vivo. Nine and twelve days following infection, BALB/c mice were injected intraperitoneally with anti-TGF-beta (1,2,3) antibodies, isotype control antibodies or isosmotic solution. We assessed both Th1 and Th2 related cytokines production ex vivo and in vitro, IgA, the number of CD4+ cells, and eosinophils in the lamina propria and the villus : crypt ratio in the small intestine 6 weeks after infection. The pattern of cytokine production differed in the intestine, peritoneal fluid and serum. In mice infected with H. polygyrus the concentrations of IL-5, IL-12, TNF-alpha and IL-10 were raised in the intestine, but in serum the level of cytokines was diminished below the value observed in uninfected mice. The neutralization of TGF-beta converted the pattern of immune response induced by H. polygyrus. The elevation of cytokines in serum coincided with the reduction of cytokine concentration in the intestine or peritoneum. Neutralization of TGF-beta restored infiltration of eosinophils into the lamina propria of the intestine despite the low level of IL-5. We conclude that H. polygyrus infection suppresses the immune response through pathways involving TGF-beta production or activity and that the Th2 related immune response was not affected by neutralization.     

新疆南,北疆绵羊源细粒棘球蚴原头节感染不同品系小鼠后发育情况的比较

为了解新疆不同地区棉羊源细粒棘球蚴对不同品系小鼠的致病力是否存在差别。用ＮＩＨ小鼠、ＣＲ鼠、ＢＡＬＢ／Ｃ小鼠和昆明株小鼠，在实验感染新疆南部和田和新疆北疆绵羊细粒棘球蚴原头节后的不同时间剖检，比较观察细粒蚴在其体内的发育状况。     

阴道毛滴虫半胱氨酸蛋白酶3基因的克隆、表达与免疫原性分析

目的 研究小鼠对阴道毛滴虫（Trichomonas vaginalis）半胱氨酸蛋白酶3（TvCP3）重组蛋白的免疫应答。 方法 用PCR方法从阴道毛滴虫基因组DNA扩增TvCP3基因编码序列,分别用编码前体酶和成熟酶的基因片段构建重组表达质粒pET28b-TvCP3和pET28b-TvCP3C,转化入大肠埃希菌（E. coli）BL21（DE3）后进行诱导表达,通过金属螯合层析法（immobilized metal affinity chromatography,IMAC）纯化表达产物重组蛋白,复性后免疫BALB/c小鼠。BALB/c小鼠分为TvCP3免疫组、TvCP3C免疫组和对照组3组,每组6只,分别用TvCP3重组蛋白、TvCP3C和PBS免疫小鼠。第1次25 μg/只,福氏完全佐剂乳化;第2次25 μg/只,福氏不完全佐剂乳化;第3次与第4次12.5 μg/只,水剂。前3次免疫间隔2周,第4次间隔1周。末次免疫后1周用ELISA测定血清抗体滴度。采集高滴度小鼠血清制备免疫血清,通过蛋白质印迹（Western blotting）分析抗体所识别的阴道毛滴虫虫体或其分泌物中的特异性抗原组分。 结果 重组表达质粒 pET28b-TvCP3和pET28b-TvCP3C均能在E. coli BL21（DE3）中高效表达,重组蛋白占菌体总蛋白的25%以上;ELISA结果显示,纯化的重组蛋白TvCP3和TvCP3C免疫小鼠4次后血清抗体效价分别达1︰204 800和1︰102 400;Western blotting分析显示,小鼠免疫血清能特异性识别表达产物中的目的蛋白,以及阴道毛滴虫虫体或分泌物中的特异性抗原组分。 结论 重组表达质粒pET28b-Tvcp3和pET28b-Tvcp3C可在E. coli BL21（DE3）中高效表达,纯化的表达产物具有良好的免疫原性。     

The virulence of Trypanosoma congolense can be determined by the antibody response of inbred strains of mice

Three inbred strains of mice, BALB/c, C57Bl/6 and CBA/J were infected with three clones of Trypanosoma congolense, DIND/3.1, SAM/28.1 and KAR/57.1, which were obtained from three different stocks. DIND/3.1 was of high virulence for BALB/c and CBA/J but of negligible virulence for C57Bl/6. SAM/28.1 was of high virulence and KAR/57.1 of negligible virulence for the three strains of mice. In each case, high virulence was correlated with a late, transient and low titre protective antibody response measured by complement mediated lysis of live organisms. Negligible virulence was correlated with an early, high titre protective antibody response. Suppression of the antibody response by sub-lethal irradiation or cyclophosphamide treatment of the host turned a trypanosome infection of negligible virulence into one of high virulence. In mice with mixed infections it was shown that highly virulent trypanosomes did not influence the course of infection and antibody response to trypanosomes of negligible virulence and vice-versa. The relationship of total antigen mass to the kinetics of the antibody response suggests that 1000- to 10,000-fold less antigen is required in good responder than in bad responder mice to trigger the immune response. Thus the virulence of T. congolense can be determined by the antibody response of inbred strains of mice. The specificity and dose dependency of this antibody response seem to implicate the involvement of Ir genes.     

Interleukin-12 Therapy Restores Cell-Mediated Immunity in Ethanol-Consuming Mice

Previous studies from our laboratory show that ethanol consumption impairs antigen-specific, cell-mediated, but not, humoral immune responses of C57BL/6, BALB/c, and D011.10 T-cell receptor transgenic mice. This ethanol-associated deficit is associated with decreased interleukin (IL)-12 and interferon–γ (IFN-γ) production, but not IL-2 or antigen-specific T-cell proliferation by explanted leukocytes from ethanol-consuming mice. IL-12 expression by macrophage/monocytes is viewed as a requirement for the production of IFN-γ by Th1 lymphocytes that mediate cellular immunity. In this study, we restored antigen-specific, cell-mediated immunity, delayed hypersensitivity, to ethanol-consuming C57BL/6 or BALB/c mice with a single 100 ng of intravenous injection of recombinant IL-12 at the time of immunization. The addition of exogenous recombinant IL-12 to co-cultures of antigen-presenting cells derived from ethanol-consuming mice and purified T cells derived from ethanol-nonconsuming DO11.10 repairs the ability of Th1 cells to make IFN-γ in response to antigen. Administration of recombinant IL-12 opens a potential for restoring cell-mediated immune function to ethanol-consuming individuals.     

A Prophylactic Effect of an Oligodeoxynucleotide Containing a Cytidine–Guanosine Motif against Japanese Cedar Pollen-Induced T-Helper Type 2 Allergic Response

Background. Over 10% of entire population in Japan suffer from allergic diseases induced by Japanese cedar pollen (JCP) every spring. In terms of preventive medicine, it has become a matter of urgency to establish successful prophylactic and therapeutic strategies for controlling the disorders. The effect of an oligodeoxynucleotide containing a cytidine–guanosine motif (CpG ODN) on the regulation of immune responses induced by JCP was investigated in this study. Methods. BALB/c mice were inoculated with CpG ODN intraperitoneally before intranasal sensitization to JCP. Cellular infiltration in the lung of BALB/c mice after treatment with CpG ODN or JCP was performed by hematoxylin and eosin (H&E) staining. Antibody titers and cytokines levels were determined by ELISA. Results. Intranasal inoculation of BALB/c mice with JCP induced a T-helper type 2 (Th2-type) dominant immune response, as characterized by the production of interleukin (IL)-4 and IL-5 in the lung and of JCP-specific IgE antibody in serum. Prior intraperitoneal administration of CpG ODN to mice suppressed the subsequent JCP-induced antibody production and infiltration of inflammatory cells in the lung. The inhibitory mechanism of CpG ODN seemed to be attributable to a CpG ODN-induced Th1-type dominant environment, which down-regulated Th2-type response subsequently induced by JCP allergen sensitization. Furthermore, administration with CpG ODN decreased the production of JCP-induced IL-17, which has been found to play a pivotal role in several inflammatory diseases including allergic asthma. The decreased production of IL-17, together with reduced secretion of IL-4 and IL-5, may contribute to diminish the inflammation in the lung of JCP-sensitized mice. Conclusion. This work provides evidence that the CpG ODN has a prophylactic effect on the JCP-induced Th2-type allergic responses by establishing or restoring a Th1-type shift of immune environments.