生物谷報(bào)道：急性病毒感染和慢性病毒感染所引起的CD8+ T細(xì)胞反應(yīng)在動(dòng)力學(xué),、反應(yīng)數(shù)量級(jí)和T細(xì)胞特異性等方面具有不同特點(diǎn)。近日,，美國(guó)科學(xué)家Miller等人對(duì)天花和黃熱病疫苗接種者的CD8+ T細(xì)胞反應(yīng)進(jìn)行了縱向分析。
天花和黃熱病疫苗接種可以很好地模擬急性病毒感染的過(guò)程,，兩種疫苗都能很快地引起大量的CD8+ 效應(yīng)T細(xì)胞產(chǎn)生,，大約兩周達(dá)到高峰期,。當(dāng)初次反應(yīng)達(dá)到最高峰,，天花和黃熱病疫苗特異性的CD8+ T細(xì)胞分別占血液中CD8+ T細(xì)胞的40%和12.5%,。 通過(guò)監(jiān)測(cè)EBV-、CMV-以及流感病毒特異性的CD8+ T細(xì)胞的反應(yīng),，證實(shí)天花和黃熱病疫苗幾乎不會(huì)引起這些病毒發(fā)生特異性CD8+ T細(xì)胞的反應(yīng),，表明無(wú)旁觀者效應(yīng)作用。四聚體染色功能分析顯示,，病毒特異性的CD8+ T細(xì)胞首先通過(guò)表達(dá)穿孔素和顆粒酶B發(fā)揮抗病毒效應(yīng),，緊接著CD8+ 效應(yīng)T細(xì)胞效應(yīng)進(jìn)入收縮期，數(shù)量減少到高峰期的10%左右,，然后逐漸分化成為能夠長(zhǎng)期存活的CD8+ 記憶性T細(xì)胞,。組合表型分析發(fā)現(xiàn)CD3、CD8,、CD38,、HLA-DR、Ki67和Bcl-2能夠用以鑒定急性病毒感染中效應(yīng)T細(xì)胞的反應(yīng),，并且效應(yīng)型T細(xì)胞分化成記憶型T細(xì)胞的過(guò)程是連續(xù)性的,。（生物谷www.bioon.com）
生物谷推薦原始出處：
Immunity，Vol 28, 710-722,，Joseph D. Miller,，Rafi Ahmed
Human Effector and Memory CD8+ T Cell Responses to Smallpox and Yellow Fever Vaccines
Joseph D. Miller,1,2 Robbert G. van der Most,1,2 Rama S. Akondy,1 John T. Glidewell,1 Sophia Albott,1 David Masopust,1 Kaja Murali-Krishna,1 Patryce L. Mahar,1 Srilatha Edupuganti,1 Susan Lalor,1 Stephanie Germon,1 Carlos Del Rio,1 Mark J. Mulligan,1 Silvija I. Staprans,1,3 John D. Altman,1 Mark B. Feinberg,1,3 and Rafi Ahmed1,
1 Emory Vaccine Center and the Hope Clinic, Emory University School of Medicine, Atlanta, GA 30322, USA
Summary
To explore the human T cell response to acute viral infection, we performed a longitudinal analysis of CD8+ T cells responding to the live yellow fever virus and smallpox vaccines—two highly successful human vaccines. Our results show that both vaccines generated a brisk primary effector CD8+ T cell response of substantial magnitude that could be readily quantitated with a simple set of four phenotypic markers. Secondly, the vaccine-induced T cell response was highly specific with minimal bystander effects. Thirdly, virus-specific CD8+ T cells passed through an obligate effector phase, contracted more than 90% and gradually differentiated into long-lived memory cells. Finally, these memory cells were highly functional and underwent a memory differentiation program distinct from that described for human CD8+ T cells specific for persistent viruses. These results provide a benchmark for CD8+ T cell responses induced by two of the most effective vaccines ever developed.
