Memory CD8+ T cells provide an early source of IFN-γ
Memory CD8+ T cells provide an early source of IFN-γ
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DOI：
10.4049/jimmunol.170.5.2399
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发表时间：
2003-03-01
影响因子：
4.4
通讯作者：
Jensen, PE
中科院分区：
文献类型：
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作者：
Kambayashi, T;Assarsson, E;Jensen, PE
在感染的非Ag特异性早期阶段，IFN-γ被认为主要由NK和NKT细胞响应于病原体来源的炎症介质而提供。为了测试其他细胞类型是否参与早期IFN-γ释放，在注射LPS的小鼠的脾和淋巴结中观察IFN-γ产生细胞。除NK和NKT细胞外，在CD8（+）T细胞的显著部分中也检测到IFN-γ。CD8（+）T细胞代表了脾中IFN-γ产生细胞的第二大群体（接近30%）和淋巴结中IFN-γ（+）细胞的大多数（接近70%）。LPS诱导的CD8（+）T细胞产生IFN-γ不依赖于MHC I类，仅限于CD44（高）（记忆表型）细胞。用C3H/HeJ（LPS无应答）小鼠进行的实验表明，CD8（+）T细胞通过巨噬细胞/树突状细胞衍生的IFN-α/β、IL-12和IL-18间接应答LPS。在注射I型IFN或poly（I：C）（一种模拟RNA病毒早期激活的合成dsRNA）的小鼠的记忆性CD8（+）T细胞中也检测到IFN-γ。综上所述，这些结果表明，在响应细菌和病毒的产品，记忆T细胞可能有助于先天性免疫，通过提供一个早期的非抗原特异性来源的IFN-γ。
During the non-Ag-specific early phase of infection, IFN-gamma is believed to be primarily provided by NK and NKT cells in response to pathogen-derived inflammatory mediators. To test whether other cell types were involved in early IFN-gamma release, IFN-gamma-producing cells were visualized in spleens and lymph nodes of LPS-injected mice. In addition to NK and NKT cells, IFN-gamma was also detected in a significant fraction of CD8(+) T cells. CD8(+) T cells represented the second major population of IFN-gamma-producing cells in the spleen (similar to30%) and the majority of IFN-gamma(+) cells in the lymph nodes (similar to70%). LPS-induced IFN-gamma production by CD8(+) T cells was MHC class I independent and was restricted to CD44(high) (memory phenotype) cells. Experiments performed with C3H/HeJ (LPS-nonresponder) mice suggested that CD8(+) T cells responded to LPS indirectly through macrophage/dendritic cell-derived IFN-alpha/beta,, IL-12, and IL-18. IFN-gamma was also detected in memory CD8(+) T cells from mice injected with type I IFN or with poly(I:C), a synthetic dsRNA that mimics early activation by RNA viruses. Taken together, these results suggest that in response to bacterial and viral products, memory T cells may contribute to innate immunity by providing an early non-Ag-specific source of IFN-gamma.