De Luca P M, Mayrink W, Pinto J A, Coutinho S G, Santiago M A, Toledo V P, Costa C A, Genaro O, Reis A B, Mendonça S C
Departamento de Imunologia, Instituto Oswaldo Cruz, FIOCRUZ, Av. Brasil 4365-Manguinhos, CP 926, CEP 21045-900, Rio de Janeiro RJ, Brazil.
Acta Trop. 2001 Dec 21;80(3):251-60. doi: 10.1016/s0001-706x(01)00181-4.
This study was aimed at evaluating the immunogenicity of a vaccine composed of killed Leishmania amazonensis promastigotes using several different protocols in a randomized, double-blind and controlled trial design in order to select one of them for further efficacy trials. One hundred and fourteen leishmanin skin test (LST)-negative healthy volunteers were allocated into eight groups that received either two or three deep intramuscular injections of vaccine at doses of 180, 360 and 540 microg or similar injections of placebo. Cell-mediated immune responses were evaluated before and after vaccination by means of LST as well as proliferative responses and cytokine production in Leishmania antigen-stimulated peripheral blood mononuclear cell cultures. The majority of the subjects who actually received vaccine converted to positive LST (89.5%). On the other hand, none of the subjects who received placebo converted to positive LST. Proliferative responses and production of interferon-gamma and interleukin-2 were significantly higher after vaccination than before vaccination in all groups, including those that received placebo. The dose of 360 microg provided the highest LST conversion rate (100%), as well as the greatest increase in interferon-gamma and interleukin-2 production after vaccination.
本研究旨在通过随机、双盲和对照试验设计，采用几种不同方案评估由灭活的亚马逊利什曼原虫前鞭毛体组成的疫苗的免疫原性，以便从中选择一种进行进一步的疗效试验。114名利什曼菌素皮肤试验（LST）阴性的健康志愿者被分为八组，分别接受180、360和540微克剂量的疫苗的两次或三次深部肌肉注射，或类似的安慰剂注射。在接种疫苗前后，通过LST以及利什曼原虫抗原刺激的外周血单核细胞培养中的增殖反应和细胞因子产生来评估细胞介导的免疫反应。实际接种疫苗的大多数受试者LST转为阳性（89.5%）。另一方面，接受安慰剂的受试者中没有一人LST转为阳性。在所有组中，包括接受安慰剂的组，接种疫苗后的增殖反应以及干扰素-γ和白细胞介素-2的产生均显著高于接种疫苗前。360微克剂量的疫苗提供了最高的LST转化率（100%），以及接种疫苗后干扰素-γ和白细胞介素-2产生的最大增加。
