Cross reactive cellular immune responses in chickens previously exposed to low pathogenic avian influenza.
Cross reactive cellular immune responses in chickens previously exposed to low pathogenic avian influenza.
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DOI：
10.1186/1753-6561-5-s4-s13
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发表时间：
2011-06-03
期刊：
影响因子：
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通讯作者：
Petkov D
中科院分区：
文献类型：
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作者：
Kapczynski DR;Liljebjelke K;Kulkarni G;Hunt H;Jiang HJ;Petkov D
禽流感在家禽中的感染可导致高发病率和高死亡率，并对国际贸易造成负面影响。由于大多数用于家禽的禽流感疫苗都是灭活的，我们对禽流感的免疫知识主要是基于体液免疫反应。事实上，对家禽感染禽流感后的细胞免疫知之甚少，特别是关于细胞毒性T淋巴细胞(CTL)。在这些研究中，将主要组织相容性复合体(MHC)定义的(B2/B2)鸡感染低致病性禽流感(LPAI)H9N2，并在两周内监测疾病的临床体征。用体外刺激的方法检测了感染和未感染鸡的脾淋巴细胞与同源和异种(H7N_2)LPAI的交叉反应。LPAI染毒后，通过B_2/B_2感染的肺靶细胞的细胞毒裂解和T细胞的增殖来检测细胞免疫。与假感染的禽类相比，感染H9N1病毒的禽类在统计上显著减轻了体重。H9N_2感染鸡的脾淋巴细胞对同源(H9N_2)和异源(H_7N_2)感染的靶细胞均表现出裂解作用，而从假感染的禽类获得的淋巴细胞则不能。当暴露于同源病毒时，T细胞增殖被确定为最高。综上所述，这些数据扩大了这样的发现，即细胞免疫，包括CTL，对异源AI分离株具有交叉反应，并有助于感染后的保护。
Avian influenza (AI) infection in poultry can result in high morbidity and mortality, and negatively affect international trade. Because most AI vaccines used for poultry are inactivated, our knowledge of immunity against AI is based largely on humoral immune responses. In fact, little is known about cellular immunity following a primary AI infection in poultry, especially regarding cytotoxic T lymphocytes (CTL’s). In these studies, major histocompatibility complex (MHC)-defined (B2/B2) chickens were infected with low pathogenic AI (LPAI) H9N2 and clinical signs of disease were monitored over a two weeks period. Splenic lymphocytes from infected and naïve birds were examined for cross reactivity against homologous and heterologous (H7N2) LPAI by ex vivo stimulation. Cellular immunity was determined by cytotoxic lysis of B2/B2 infected lung target cells and proliferation of T cells following exposure to LPAI. Infection with H9N2 resulted in statistically significant weight loss compared to sham-infected birds. Splenic lymphocytes derived from H9N2-infected birds displayed lysis of both homologous (H9N2) and heterologous (H7N2) infected target cells, whereas lymphocytes obtained from sham-infected birds did not. T cell proliferation was determined to be highest when exposed to the homologous virus. Taken together these data extend the findings that cellular immunity, including CTL’s, is cross reactive against heterologous isolates of AI and contribute to protection following infection.