傳統(tǒng)觀點(diǎn)認(rèn)為,，胎兒的免疫系統(tǒng)極為脆弱，對(duì)病毒只能作出基本的反應(yīng),，根本無法達(dá)到一般成年人所具有的能精準(zhǔn)定位的防御水平,。然而，最近美國科學(xué)家的研究打破了這一觀點(diǎn),。
來自哥倫比亞大學(xué)過敏癥學(xué)家和免疫學(xué)家Rachel Miller相信,，胚胎免疫系統(tǒng)比研究人員想象的要高級(jí)的多。
Miller與其同事征集了126名妊娠期間接受過禽流感疫苗注射的126名孕婦為志愿者,。這些婦女生產(chǎn)時(shí),，Miller采集每位新生兒的臍帶血樣本，共得到70個(gè)可用樣本,，并利用一種從未在臍帶血中應(yīng)用的技術(shù)在細(xì)胞水平觀察免疫反應(yīng),。他們一個(gè)細(xì)胞一個(gè)細(xì)胞地鑒別，是否胚胎在對(duì)流感疫苗的反應(yīng)中產(chǎn)生特定抗體,。他們發(fā)現(xiàn)40％的樣本含產(chǎn)生了能夠攻擊流感病毒的抗體和T細(xì)胞,。Miller說，還不清楚的是為何只有某些胚胎呈現(xiàn)了免疫反應(yīng),，但她說值得注意的是存在流感特異抗體,，一些是體積過大無法從母體通過胎盤到達(dá)胎兒的IgM抗體，這意味著它們無疑是胎兒產(chǎn)生的,。這一成果刊登于6月1日《Clinical Investigation》,。
來自威斯康星大學(xué)麥迪遜分校（University of Wisconsin-Madison）的免疫學(xué)家William Burlingham說："這表明，從誕生那刻起，嬰兒便具有了一個(gè)較成熟的免疫系統(tǒng),。"
雖然胎兒的免疫系統(tǒng)是否強(qiáng)大到足夠抵御病毒的侵?jǐn)_還有待證實(shí),，但是這些免疫細(xì)胞的存在已經(jīng)表明，這種新生的免疫系統(tǒng)能夠產(chǎn)生免疫細(xì)胞以對(duì)抗特定的抗原,。
來自哈佛醫(yī)學(xué)院的內(nèi)科醫(yī)生及免疫學(xué)家Ofer Levy說,，如果新生兒由此真的具有了抵抗病毒的能力，那么這項(xiàng)研究成果將對(duì)公眾健康產(chǎn)生重要的意義,。他說："如果優(yōu)化疫苗,，那么你將能夠增加同時(shí)保護(hù)母親和新生兒的可能性。"
胎兒通過胎盤,，從母體處獲得長達(dá)6個(gè)月的抗體供應(yīng),，為其抵抗充滿敏感誘發(fā)顆粒和病毒的外部世界進(jìn)行武裝。最新研究結(jié)果提示發(fā)育過程中的胎兒能夠?qū)碜阅阁w的流感疫苗進(jìn)行特異免疫反應(yīng),。這項(xiàng)發(fā)現(xiàn)有助于結(jié)束圍繞胚胎免疫系統(tǒng)復(fù)雜性的爭(zhēng)論,。
威斯康星州立大學(xué)免疫學(xué)家Aimen Shaaban說，這項(xiàng)成果證實(shí)了“胚胎可以進(jìn)行特定免疫反應(yīng)”的長期爭(zhēng)論的理論,，是該領(lǐng)域的一顆重磅炸彈,。但他也強(qiáng)調(diào)，疫苗接種在三個(gè)月時(shí)進(jìn)行,，因?yàn)槟菚r(shí)的胚胎免疫系統(tǒng)有時(shí)間變得更復(fù)雜,。Shaaban說認(rèn)為，重復(fù)工作有助于觀察早期trimesters時(shí)的胚胎,，確定這種先進(jìn)的免疫系統(tǒng)反應(yīng)開始工作的確切時(shí)間,。
原始出處:
J. Clin. Invest. 117:1637-1646 (2007). doi:10.1172/JCI29466.
Research Article
Antigen-specific immune responses to influenza vaccine in utero
Deepa Rastogi1, Chaodong Wang2, Xia Mao3, Cynthia Lendor3, Paul B. Rothman4 and Rachel L. Miller3
1Children’s Hospital at Montefiore, Albert Einstein College of Medicine, New York, New York, USA. 2Department of Neurology, Jiangxi Provincial People’s Hospital, Nanchang, People’s Republic of China. 3Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York, New York, USA. 4Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA.
Address correspondence to: Rachel L. Miller, PH8C, Columbia University College of Physicians and Surgeons, 630 W. 168th Street, New York, New York 10032, USA. Phone: (212) 305-7759; Fax: (212) 305-2277; E-mail: [email protected] .
Received for publication June 21, 2006, and accepted in revised form April 9, 2007.
Abstract
Initial immune responses to allergens may occur before birth, thereby modulating the subsequent development of atopy. This paradigm remains controversial, however, due to the inability to identify antigen-specific T cells in cord blood. The advent of MHC tetramers has revolutionized the detection of antigen-specific T cells. Tetramer staining of cord blood after CMV infection has demonstrated that effective CD8+ antigen-specific immune responses can follow intrauterine viral infections. We hypothesized that sensitization to antigens occurs in utero in humans. We studied cord blood B and T cell immune responses following vaccination against influenza during pregnancy. Anti-Fluzone and anti-matrix protein IgM antibodies were detected in 38.5% (27 of 70) and 40.0% (28 of 70), respectively, of cord blood specimens. Using MHC tetramers, HA-specific CD4+ T cells were detected among 25.0% (3 of 12) and 42.9% (6 of 14) of cord blood specimens possessing DRB1*0101 and DRB1*0401 HLA types, respectively, and were detected even when the DRB1 HLA type was inherited from the father. Matrix protein–specific CD8+ T cells were detected among 10.0% (2 of 20) of HLA-A*0201+ newborns. These results suggest that B and T cell immune responses occur in the fetus following vaccination against influenza and have important implications for determining when immune responses to environmental exposures begin.
