兩個愛潑斯坦-巴爾病毒(Epstein-Barr virus, EBV)顆粒，圖片來自維基共享資源,。
根據(jù)2012年3月5日發(fā)表在Journal of Experimental Medicine期刊上的一篇研究論文,，人類免疫系統(tǒng)產(chǎn)生的新記憶并不是以舊記憶消失為代價。
記憶殺傷性T細(xì)胞(memory killer T cell)是一類特化細(xì)胞(specialized cell),，是在對特定感染做出免疫應(yīng)答后產(chǎn)生的,。小鼠實驗已表明產(chǎn)生新的記憶T細(xì)胞導(dǎo)致舊的記憶T細(xì)胞激活和隨后的死亡，這可能是因為小鼠免疫系統(tǒng)只能容納一定數(shù)目的記憶T細(xì)胞,。
但是人類免疫系通過似乎不受這種空間限制的制約,。在對大學(xué)生進(jìn)行的追蹤性研究中，來自美國明尼蘇達(dá)大學(xué)醫(yī)學(xué)院的Kristin Hogquist和同事們發(fā)現(xiàn)愛潑斯坦-巴爾病毒(Epstein-Barr virus, EBV，它是導(dǎo)致傳染性單核細(xì)胞增多癥產(chǎn)生的病因)導(dǎo)致的急性感染觸發(fā)其他病毒特異性的記憶T細(xì)胞激活,。但是這些細(xì)胞既不增殖也不會死亡,，也就意味著它們的數(shù)目不受時間影響，一直保持不變,。
因此,，人類記憶T細(xì)胞只會隨著時間的增加而不斷堆積。這對免疫應(yīng)答是否產(chǎn)生有益或者有害影響還有待進(jìn)一步觀察,。(生物谷：towersimper編譯)
doi:10.1084/jem.20112401
PMC:
PMID:
Primary Epstein-Barr virus infection does not erode preexisting CD8+ T cell memory in humans
Oludare A. Odumade, Jennifer A. Knight, David O. Schmeling, David Masopust, Henry H. Balfour Jr., and Kristin A. Hogquist
Acute Epstein-Barr virus (EBV) infection results in an unusually robust CD8+ T cell response in young adults. Based on mouse studies, such a response would be predicted to result in attrition of preexisting memory to heterologous infections like influenza A (Flu) and cytomegalovirus (CMV). Furthermore, many studies have attempted to define the lymphocytosis that occurs during acute EBV infection in humans, but it is unclear whether bystander T cells contribute to it. To address these issues, we performed a longitudinal prospective study of primary EBV infection in humans. During acute EBV infection, both preexisting CMV- and Flu-specific memory CD8+ T cells showed signs of bystander activation, including up-regulation of granzyme B. However, they generally did not expand, suggesting that the profound CD8+ lymphocytosis associated with acute EBV infection is composed largely of EBV-specific T cells. Importantly, the numbers of CMV- and Flu-specific T cells were comparable before and after acute EBV infection. The data support the concept that, in humans, a robust CD8+ T cell response creates a new memory CD8+ T cell niche without substantially depleting preexisting memory for heterologous infections.
