Stoute J A, Kester K E, Krzych U, Wellde B T, Hall T, White K, Glenn G, Ockenhouse C F, Garcon N, Schwenk R, Lanar D E, Sun P, Momin P, Wirtz R A, Golenda C, Slaoui M, Wortmann G, Holland C, Dowler M, Cohen J, Ballou W R
Department of Immunology, Walter Reed Army Institute of Research, Washington, DC, USA.
J Infect Dis. 1998 Oct;178(4):1139-44. doi: 10.1086/515657.
The malaria sporozoite vaccine candidate RTS,S, formulated with an oil-in-water emulsion plus the immunostimulants monophosphoryl lipid A and the saponin derivative QS21 (vaccine 3), recently showed superior efficacy over two other experimental formulations. Immunized volunteers were followed to determine the duration of protective immune responses. Antibody levels decreased to between one-third and one-half of peak values 6 months after the last dose of vaccine. T cell proliferation and interferon-gamma production in vitro were observed in response to RTS,S or hepatitis B surface antigen. Seven previously protected volunteers received sporozoite challenge, and 2 remained protected (1/1 for vaccine 1, 0/1 for vaccine 2, and 1/5 for vaccine 3). The prepatent period was 10.8 days for the control group and 13.2 days for the vaccinees (P < .01). Immune responses did not correlate with protection. Further optimization in vaccine composition and/or immunization schedule will be required to induce longer-lasting protective immunity.
疟疾子孢子候选疫苗RTS,S，与水包油乳剂以及免疫刺激剂单磷酰脂质A和皂苷衍生物QS21（疫苗3）一起配制，最近显示出比其他两种实验制剂更优的疗效。对免疫的志愿者进行随访以确定保护性免疫反应的持续时间。最后一剂疫苗接种6个月后，抗体水平降至峰值的三分之一至二分之一之间。观察到针对RTS,S或乙型肝炎表面抗原的体外T细胞增殖和γ干扰素产生。7名先前受到保护的志愿者接受了子孢子攻击，2人仍受到保护（疫苗1为1/1，疫苗2为0/1，疫苗3为1/5）。对照组的潜伏期为10.8天，疫苗接种者为13.2天（P<0.01）。免疫反应与保护作用无关。需要进一步优化疫苗组成和/或免疫程序以诱导更持久的保护性免疫。
