Response of BALB/c mice to a monovalent influenza A （H1N1） 2009 split vaccine

The novel influenza A (H1N1) 2009 virus has emerged to cause the first pandemic of the twenty-first century. Disease outbreaks caused by the influenza A (H1N1) virus have prompted concerns about the potential for a pandemic and have driven the development of vaccines against this subtype of influenza A. In this study, we developed a monovalent influenza A (H1N1) split vaccine and evaluated its effects in BALB/c mice. Mice were immunized subcutaneously with 2 doses of the vaccine containing hemagglutinin (HA) alone or HA plus an aluminum hydroxide (Al(OH)₃) adjuvant. Immunization with varying doses of HA (3.75, 7.5, 15, 30, 45 or 60 µg) was performed to induce the production of neutralizing antibodies. The vaccine elicited strong hemagglutination inhibition (HI) and microneutralization, and addition of the adjuvant augmented the antibody response. A preliminary safety evaluation showed that the vaccine was not toxic at large doses (0.5 ml containing 60 µg HA+600 µg Al(OH)₃ or 60 µg HA). Moreover, the vaccine was found to be safe at a dose of 120 µg HA+1200 µg Al(OH)₃ or 120 µg HA in 1.0 ml in rats. In conclusion, the present study provides support for the clinical evaluation of influenza A (H1N1) vaccination as a public health intervention to mitigate a possible pandemic. Additionally, our findings support the further evaluation of the vaccine used in this study in primates or humans.     

禽流感病毒感染BALB／c小鼠的动态病理观察

目的将H5N1亚型禽流感病毒（AIV）鼻腔接种BALB／c小鼠,动态观察小鼠每个时期主要器官组织的病理变化。方法将100μlH5N1亚型禽流感病毒原液滴入经麻醉后BALB／c小鼠鼻腔,观察14d,每天取材1次,固定、包埋、切片后HE染色观察各组织病理变化。结果H5N1亚型禽流感病毒感染BALB／c小鼠后,产生一系列与禽流感病毒感染有关的动态病理改变：第1～2天（前驱期）,肺轻微出血、水肿、炎性细胞浸润;第3～7天（发作期）,肺损伤逐渐严重．大量出血、炎性细胞浸润、严重水肿、淤血、肺泡实变塌陷或者气肿;第8～14天（恢复期）,各种损伤逐渐减轻,出血渗出减少,水肿减轻,肺间质出现纤维化而趋于恢复正常。肝、。肾、脑出现病理改变。结论通过动态观察病理,弄清了禽流感病毒每个时期在BALB／c小鼠体内造成的病理损伤。     

补中益气汤对A549/DDP肺腺癌耐药动物模型中凋亡相关信号分子caspase-9的影响

目的研究补中益气汤对肺腺癌荷瘤BALB/c小鼠实体瘤中凋亡相关信号分子Caspase-9表达的影响,探讨其对肺腺癌可能的作用机制。方法体外培养肺腺癌A549/DDP细胞,接种健康BALB/c小鼠,荷瘤成功后予补中益气汤治疗,实验分为:荷瘤对照组,补中益气汤低剂量组及补中益气汤高剂量组。观察转移病灶情况,利用RT-PCR检测Caspase-9 mRNA的表达,免疫组化法检测Caspase-9蛋白表达。结果同荷瘤对照组相比,高、低剂量的补中益气汤均可上调凋亡相关信号分子Caspase-9 mRNA和蛋白的表达水平,并且补中益气汤高剂量组效果优于低剂量组。结论补中益气汤对肺腺癌的抑制作用可能与Caspase-9表达上调相关。     

BALB/c mice resistant to Toxoplasma gondii infection proved to be highly susceptible when previously infected with Myocoptes musculinus fur mites

The immune response induced by Toxoplasma gondii is characterized by Th1 immune mechanisms. We previously demonstrated that C57BL/6 mice infested with Myocoptes musculinus and infected with T. gondii by intraperitoneal route undergo accelerated mortality according to Th2 immune mechanisms induced by the acarian. To evaluate whether infection with M. musculinus influences T. gondii-induced Th1 response in a resistant mouse lineage, BALB/c, which develops latent chronic toxoplasmosis in a way similar to that observed in immunocompetent humans, this study was done. The animals were infected with T. gondii ME-49 strain 1 month after M. musculinus infestation, being the survival and the immune response monitored. The double-infected displayed higher mortality rate if compared with the mono-infected mice. In addition, infection with M. musculinus changed the T. gondii-specific immune response, converting BALB/c host to a susceptible phenotype. Spleen cells had increased the levels of IL-4 in double-infected mice. This alteration was associated with severe pneumonia, encephalitis and wasting condition. In addition, a higher tissue parasitism was observed in double-infected animals. It can be concluded that infection with these two contrasting parasites, M. musculinus and T. gondii, may convert an immunocompetent host into a susceptible one, and such a host will develop severe toxoplasmosis.     

An enterovirus 71 strain causes skeletal muscle damage in infected mice

Objective: To study the target organs for enterovirus 71 (EV71) in infected suckling mice. Methods: 5-day-old BALB/c suckling mice were infected with an EV71 strain. Tissues of the infected mice were processed for histopathological examination, including immunohistochemistry, in situ hybridization, ultrastructural observation. Results: Some mice developed limb paralysis, trouble walking and loss of balance. Results of the histopathological study showed that a large amount of EV71 existed in the skeletal muscle tissues, accounting for the damage of the skeletal muscles. Conclusion: The EV71 clinical isolate used in this study presented evident myotropism. Skeletal muscles are important target organs for EV71 in the infected suckling mice. To clarify the relationship between EV71 infection and muscle diseases may contribute to a better understanding of the pathogenesis of EV71.     

Obesity promotes prolonged ovalbumin‐induced airway inflammation modulating T helper type 1 (Th1), Th2 and Th17 immune responses in BALB/c mice

Clinical and epidemiological studies indicate that obesity affects the development and phenotype of asthma by inducing inflammatory mechanisms in addition to eosinophilic inflammation. The aim of this study was to assess the effect of obesity on allergic airway inflammation and T helper type 2 (Th2) immune responses using an experimental model of asthma in BALB/c mice. Mice fed a high‐fat diet (HFD) for 10 weeks were sensitized and challenged with ovalbumin (OVA), and analyses were performed at 24 and 48 h after the last OVA challenge. Obesity induced an increase of inducible nitric oxide synthase (iNOS)‐expressing macrophages and neutrophils which peaked at 48 h after the last OVA challenge, and was associated with higher levels of interleukin (IL)‐4, IL‐9, IL‐17A, leptin and interferon (IFN)‐γ in the lungs. Higher goblet cell hyperplasia was associated with elevated mast cell influx into the lungs and trachea in the obese allergic mice. In contrast, early eosinophil influx and lower levels of IL‐25, thymic stromal lymphopoietin (TSLP), CCL11 and OVA‐specific immunoglobulin (IgE) were observed in the obese allergic mice in comparison to non‐obese allergic mice. Moreover, obese mice showed higher numbers of mast cells regardless of OVA challenge. These results indicate that obesity affects allergic airway inflammation through mechanisms involving mast cell influx and the release of TSLP and IL‐25, which favoured a delayed immune response with an exacerbated Th1, Th2 and Th17 profile. In this scenario, an intense mixed inflammatory granulocyte influx, classically activated macrophage accumulation and intense mucus production may contribute to a refractory therapeutic response and exacerbate asthma severity.     

Hepatic extracellular matrix in BALB/c mice infected with Leishmania donovani

The development of the extracellular matrix (ECM) in the liver of the BALB/c mouse infected with Leishmania donovani was observed by histology, immunocytochemistry and electron microscopy at 1, 2, 4, 8, 14 and 20 weeks after infection. Collagen III and proteoglycan were detected in granulomas and in the portal spaces from 4 to 20 weeks after infection. Laminin was not detected in granulomas but was observed in the basement membrane of new small blood vessels in the granulation tissue around the portal spaces from 8 to 20 weeks after infection. The ECM components in the space of Disse showed no changes in distribution throughout the entire period of study. Systemic fibrosis in the hepatic lobule was not evident in the BALB/c mice. This mouse strain does not appear to be an appropriate model to study the role of ECM in chronic visceral leishmaniasis.     

小鼠哮喘气道重构模型的建立及组织形态计量学定位定量初步研究

目的：建立BALB/c小鼠哮喘气道重构模型,确立该模型的肺组织形态计量学定位定量指标。方法：(1)使用自凝造牙粉和自凝牙托水制作BALB/c小鼠的支气管树树脂铸型,确定肺组织形态学测量的具体部位。(2)30只BALB/c小鼠随机分为正常组、对照组和模型组,每组10只。观察3组小鼠一般整体改变、支气管肺泡灌洗液（BALF）中嗜酸性粒细胞(EOS)计数和肺组织切片HE染色光镜下大体病理改变,确定模型是否成功;同时对肺组织切片进行阿利辛蓝-过碘酸雪夫（AB-PAS）染色,以Image-Pro Plus 6.0图像分析软件在确定的目标部位测量上皮层厚度、平滑肌层厚度、杯状细胞计数和杯状细胞面积占上皮层面积百分比,确定正常参考值。结果：（1）成功建立BALB/c小鼠支气管树树脂铸型。（2）模型组小鼠的整体改变、BALF 中嗜酸性粒细胞计数以及HE染色光镜下肺组织病理学改变均证实成功建立了哮喘气道重构模型。（3）AB-PAS染色结果显示模型组目标气道上皮层厚度、平滑肌层厚度、杯状细胞计数和杯状细胞面积占上皮层面积百分比测量值均显著高于正常组和空白对照组（P<0.01）。结论：通过支气管树树脂铸型确定的目标支气管能够作为哮喘气道重构形态计量学分析的有效部位。     

BALB/c和SCID小鼠人偏肺病毒感染特点的比较研究

目的 比较研究人偏肺病毒(hMPV)在BALB/c小鼠和SCID小鼠肺内复制动力学和肺病理特点.方法 GFP-rhMPV滴鼻感染BALB/c小鼠和SCID小鼠,于感染后3、5、7、9、14d处死小鼠并无菌获取心、肝、脾、肺、肾和脑用于病毒分离和病理检查,空斑形成法检测病毒滴度,RT-PCR和real-time PCR法检测hMPV mRNA表达.结果 GFP-rhMPV滴鼻感染BALB/c小鼠和SCID小鼠后第5天肺组织均分离到病毒.感染GFP-rhMPV的BALB/c和SCID小鼠在感染后第5天肺组织病毒滴度均达峰值,分别为(5.25±1.69)×104 PFU/g和(5.83±1.21)×105 PFU/g.SCID小鼠在感染后第14天肺组织内病毒滴度仍可达(4.25±1.04) ×101 PFU/g,此时BALB/c鼠肺内已不能分离到病毒,但可检测到GFP-rhMPV F蛋白mRNA表达.感染后第5天所有小鼠的心、肝、脾、肾和脑组织内均不能分离到病毒,也无法检测到hMPV F蛋白mRNA表达.肺组织病理改变在感染后第5天最明显,为典型的间质性肺炎改变,BALB/c小鼠组肺组织病理评分略低于SCID小鼠组,差异无统计学意义.结论 GFP-rhMPV滴鼻感染后只能在小鼠肺内复制.同BAL B/c小鼠相比,SCID小鼠感染GFP-rhMPV后肺内病毒滴度高,复制时间久,但病理损伤无明显差异.     

Pathogenesis of acute myocardial necrosis in inbred mice infected with coxsackievirus B3

The pathogenesis of myocardial necrosis due to CB3W infection was studied in BALB/c and C3H/HeJ mice. BALB/c mice infected with 5 x 10(4) pfu were found to die of massive hepatic coagulative necrosis before myocardial changes occurred. Reducing the inoculum size to 5 x 10(2) pfu resulted in sublethal hepatic involvement and multifocal myocardial coagulative necrosis by day 7 p.i. In contrast, C3H/HeJ mice survived infection and developed multifocal myocardial coagulative necrosis, but not liver disease following inoculation with as much as 5 x 10(6) pfu of CB3W. As with BALB/c mice infected with 5 x 10(2) pfu, myocardial lesions became apparent in C3H/HeJ mice a few days after peak cardiac virus titer was attained. Minimal inflammatory infiltrate was seen following development of cellular necrosis and was restricted to the areas of virus-induced pathologic change. However, no evidence was found for virus-specific cytotoxic T cell activity or for delayed type hypersensitivity responses. Furthermore, myocardial necrosis in CB3W-infected, T cell-depleted C3H/HeJ mice was as severe as in CB3W-infected, immunocompetent mice. These data have led us to conclude that cardiac lesions were due to virus-induced cytopathology rather than immunopathogenic mechanisms.     

Hospital‐based influenza surveillance in Korea: Hospital‐based influenza morbidity and mortality study group

Influenza epidemics occur annually with variations in size and severity. Hospital‐based Influenza Morbidity & Mortality was established to monitor influenza epidemics and their severity, which is composed of two surveillance systems: emergency room‐based and inpatient‐based surveillance. Regarding emergency room‐based surveillance, influenza‐like illness index (influenza‐like illness cases per 1,000 emergency room‐visiting subjects), number of laboratory‐confirmed cases and the distribution of influenza types were estimated weekly. Inpatient‐based surveillance included monitoring for hospitalization, complications, and mortality. The emergency room influenza‐like illness index correlated well with the number of laboratory‐confirmed influenza cases, and showed a bimodal peak at Week 4 (179.2/1,000 emergency room visits) and Weeks 13‐14 (169.6/1,000 emergency room visits) of 2012. Influenza A was the predominant strain during the first epidemic peak, while influenza B was isolated exclusively during the second peak. In 2011–2012 season, the mean admission rate of emergency room‐visiting patients with influenza‐like illness was 16.3% without any increase over the epidemic period. Among the hospitalized patients with influenza, 33.6% (41 out of 122 patients) were accompanied by complications, and pneumonia (28.7%, 35 out of 122 patients) was the most common. Most fatal cases were caused by influenza A (96.2%) after the first epidemic peak. In conclusion, Hospital‐based Influenza Morbidity & Mortality was effective for monitoring the trends in circulating influenza activity concurrently with its severity. In the 2011–2012 season, the influenza epidemic persisted for a ≥5‐month period, with a bimodal peak of influenza A and B in sequence. Overall, influenza A was more severe than influenza B. J. Med. Virol. 85:910–917, 2013. © 2013 Wiley Periodicals, Inc.     

禽流感H5N1亚型病毒感染BALB/c小鼠的免疫应答

目的 研究禽流感H5N1病毒感染BALB/c小鼠后对宿主细胞免疫功能和细胞因子水平变化的影响,探讨禽流感H5N1病毒感染哺乳动物的免疫发病机制.方法 选用鹅源禽流感H5N1病毒感染BALB/c小鼠,采用流式细胞仪检测血液和脾脏T淋巴细胞及其亚群的变化,采用ELISA检测血液中细胞岗子(IFN-γ、TNF-α、IL-4、IL-18、IL-10、IL-2)及禽流感H5N1病毒特异性抗体的变化.结果 禽流感H5N1病毒感染可引起对宿主短暂的、可恢复的细胞免疫功能损伤:血液CD3+、CD4+、CD8+ T淋巴细胞数量于染毒后第2～4天下降(第4天为最低值),脾脏T淋巴细胞数最于染毒后第5～8天下降(第6天为最低值),然后均逐渐恢复到正常水平.染毒后血液细胞因子变化表现为:血清IFN-γ、TNF-α水平下降,IL-4、IL-18、IL-10水平上升,IL-2水平无明显变化.从感染第7天开始检测H5N1禽流感特异性抗体为阳性,抗体水平逐渐升高至实验结束的感染第14天.结论 H5N1禽流感病毒感染可引起宿主T细胞免疫功能低下是其主要的免疫病理改变之一,细胞因子表达失平衡或过多的表达都可能对宿主产生免疫病理损伤.

Abstract：

Objective To study the cell immunity and eytokines responses to avian influenza A H5N1 virus infections in a BALB/c model to better understand the pathogenesis of H5N1 avian influenza disease. Methods Two hundred and twenty BALB/c mice of the infected group were inoculated with 0.1 ml (10-4.875 TCID50) of A/Goose/Guangdong/NH/2003 ( H5N1 ) virus intra-nasally. Fifty control mice received noninfectious allantoic fluid and another fifty control mice received normal sodium. Blood and spleen samples were collected from the live mice every 24 h during the 14 d post-infection. The changes of CD3 + T cells , CD4 + T cells, CD8 + T cells for cell immunity in blood circulation and spleen were detected by flow cytometry. And the cytokines and antibody responses in blood circulation were detected by ELISA. Necropsy was performed on mice that died during the experiment and those euthanized at end of study. Results Avian influenza A( H5N1) virus infections can make damages to the cell immune system transiently. The CD3 + T cells, CD4 + T cells, CDS + T cells declined at 24 days post infection in blood circulation and declined at 5-8 days in spleen, then recovered to the normal level gradually. The eytokines responses to the infections can be detected: the level of IFN-γ,TNF-α declined, IL-4, IL-18, IL-10 increased, and IL-2 changed little. The antibody increased rapidly from day 7 post infection until the end of the study (day 14 post infection). Conclusion Collectively, avian influenza A(H5N1) virus can cause cell immunity deficiency and an imbalance in the level of eytokines, which may contribute to the unusual severity of disease caused by the H5N1 avian influenza virus.     

补中益气汤对A549/DDP肺癌荷瘤BALB/c小鼠耐药相关蛋白MRP表达的影响

目的研究补中益气汤对A549/DDP肺癌荷瘤BALB/c小鼠实体瘤中耐药相关蛋白(multidrug resistance-associated protein,MRP)表达的影响,探讨补中益气汤对A549/DDP的治疗作用机制。方法体外培养A549/DDP细胞,接种健康BALB/c小鼠,荷瘤成功后予补中益气汤治疗,实验分组为:荷瘤对照组,补中益气汤低剂量组及补中益气汤高剂量组,利用RT-PCR检测实体瘤MRP mRNA的表达,免疫组化法检测MRP蛋白表达。结果同荷瘤对照组相比,高、低剂量的补中益气汤均可降低耐药相关蛋白MRP的表达水平,且补中益气汤高剂量组效果同低剂量组相比无明显区别。结论补中益气汤的抗肿瘤作用可能与其降低MRP的表达相关。     

CD8+ T cells are the major lymphocyte subpopulation involved in the protective immune response to Toxoplasma gondii in mice.

The ability of the major T cell subsets to adoptively transfer resistance to T. gondii infection was studied. Spleen cells harvested from mice with a 3-month T. gondii infection and cells from uninfected mice were enriched for T cells by nylon/wool purification. Adoptive transfer of these cells from both groups of donor mice led to a significant increase in the survival of syngeneic recipient mice infected intraperitoneally with 20 T. gondii cysts. Increased survival was mediated particularly by CD4-depleted but also, to a lesser extent, CD8-depleted subpopulations. These results were confirmed in T cell reconstituted athymic nude mice. Unfractionated T cells from chronically infected donors produced a significant inhibition of cyst formation in the brains of recipient mice measured 10 weeks after infection compared with control mice. The inhibition of cyst formation was ablated by pretreating T cells with anti-CD8 antibody and complement, but not anti-CD4 antibody and complement. Mice receiving cells from infected donors produced an early increase in their IgG1 and IgG2a antibody titres compared with mice given cells from uninfected animals. The depletion of either CD8+ or CD4+ immune cells appeared to have little effect on the antibody responses in recipient mice and there was no correlation between antibody levels and immunity. The results indicate that CD8+ T lymphocytes from convalescent T. gondii-infected BALB/c mice are the principal mediators of resistance to T. gondii, although CD4+ T cells appear to be involved during the acute phase of infection.     

Pathogenic autoimmunity to affinity-purified mouse acetylcholine receptor induced without adjuvant in BALB/c mice

Myasthenia gravis (MG) and experimental autoimmune myasthenia gravis (EAMG) are antibody-mediated disorders in which anti-acetylcholine receptor (anti-AChR) antibodies cause loss of muscle AChR and subsequent weakness. Many species are susceptible to induction of EAMG with purified xenogeneic AChR in adjuvant, but injection of Torpedo AChR without adjuvants can also induce evidence of EAMG. To see whether pathogenic autoimmunity could be induced in mice by isolated mouse AChR we injected BALB/c mice with several doses (1 pmole; about 0.1 ug) of affinity-purified AChR (from the BC3H1 cell line but thought to be identical with denervated mouse muscle) intraperitoneally, without adjuvant, over a period of 10-22 weeks. Some of the mice became ill and died. High levels of serum anti-mouse AChR, directed mainly towards the main immunogenic region, were found and, in the survivors, correlated with loss of muscle AChR. Thus BALB/c mice can mount an autoimmune response to minute amounts of mouse AChR, without the use of adjuvants, and this response is very similar to that found in MG. This novel finding has implications regarding the etiology of the human disease.     

Effects on antitumor activity and cytokine production in the thoracic cavity by intrapleural administration of Lactobacillus casei in tumor-bearing mice

The effects Lactobacillus casei YIT9108 (LC 9018) on antitumor activity and cytokine production in Meth A fibrosarcoma (Meth A)-bearing BALB/c mice were examined. Intrapleural (i.pl.) administration of LC 9018 was effective in prolonging the survival of Meth A-bearing mice, and frequently cured mice of the tumor. However, the results also indicated that the effect of LC 9018 was in part inhibited in mice treated with anti-CD3 or anti-CD8 antibody, but not affected in anti-CD4 antibody-treated mice. In contrast, LC 9018 had little effect on Meth A-bearing SCID or nude mice. These results demonstrated that CD8⁺ T cells participated in prolonging the survival of Meth A-bearing mice. Moreover, the examination of the production of several cytokines revealed that the production of interferon-γ and interleukin-6 was, in particular, augmented in the exudated fluid of the thoracic cavity in BALB/c mice injected with LC 9018 i.pl. These results suggested that i.pl. administration of LC 9018 induced those cytokines which had the potential to activate the thoracic macrophages or proliferate the thoracic lymphocytes to the cytotoxic T cells. Taken together, these findings demonstrated that the prolonging effects on survival by i.pl. administration of LC 9018 depended on CD8⁺ T cells, and the i.pl. administration of LC 9018 into i.pl. Meth A-bearing mice induced several cytokines which participated in the subsequent immunoresponses. Received: 24 June 1996     

Structural changes in the liver of mice infected with avian influenza virus subtype H5N1

Intranasal infection of male outbred rats with isolate of influenza A virus subtype H5N1 (A/Gs/Krasnoozerskoye/627/05) from the Novosibirsk region was followed by high mortality of experimental animals. Morphological study of liver samples revealed subtotal destructive changes in the liver parenchyma (proteinosis and centrolobular necroses), which was related to hemodynamic disorders and cytokine dysregulation. The decrease in reparative activity of hepatocytes was probably followed by hepatocellular failure and contributed to high mortality rate from this infection (up to 85%). Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 146, No. 8, pp. 210–212, August, 2008     

Differential strain‐related tissue immune response to sublethal systemic Aspergillus fumigatus infection in mice

Using a nonlethal systemic Aspergillus fumigatus infection, we have recently shown that similarly efficient elimination of fungus from spleens of prototypic Th1 (C57BL/6) and prototypic Th2 (BALB/c) mice is associated with differential immune responses. In light of these data and given the disseminated character of infection, the aim of the present study is to explore whether there are also strain‐dependent differences in antifungal responses in peripheral tissues of infected mice. Although similar efficiency of conidia removal was noted in liver and kidneys of both strains, BALB/c mice seemed more prone to tissue injury. Compared with other nonlymphoid organs, lungs proved immunologically the most responsive in systemic aspergillosis. Lower numbers of neutrophils and macrophages in the lungs of infected BALB/c mice, delayed and lower (compared with C57BL/6 mice) expression of their oxidative activity, along with late IFN‐γ and upregulated IL‐4 production by lung cells might be responsible for slower elimination of A. fumigatus from the lungs of this mouse strain. The data obtained imply that lungs should be viewed as mandatory organ in evaluation of immune‐mediated antifungal potential of drugs in models of systemic/disseminated infection and that strain differences noted in tissue responses should be taken into account in these settings.