Bacellar O, Barral-Netto M, Badaró R, Carvalho E M
Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Brasil.
Braz J Med Biol Res. 1991;24(8):791-5.
The present study was performed to evaluate the ability of lymphocytes from 18 children living in an endemic area of visceral leishmaniasis (VL) to produce gamma-interferon. These children had no previous history of VL and were considered to be infected with Leishmania chagasi based on leishmanial seroconversion. The gamma IFN levels were determined by radioimmunoassay on supernatants of lymphocyte cultures (3 x 10(6)/ml) stimulated with PHA (final dilution 1:10) and Leishmania chagasi antigen (10 micrograms/ml). The gamma-IFN production by lymphocytes from seroconverting children stimulated with PHA (178 +/- 151 U/ml) and Leishmania chagasi (47 +/- 77 U/ml) was significantly higher than that observed in visceral leishmaniasis. For clinical follow-up, these 18 seroconverting children were divided into three groups: asymptomatic infection (N = 4); self-healing subclinical illness (N = 9), and subclinical infection progressing to VL (N = 5). Gamma IFN levels in children with either asymptomatic or subclinical infection (65 +/- 85 U/ml) were significantly higher (P less than 0.003) than those observed in children progressing to VL (9 +/- 6 U/ml). The data demonstrate that there is an association between gamma IFN levels and the clinical course of Leishmania infection.
本研究旨在评估来自内脏利什曼病（VL）流行地区的18名儿童的淋巴细胞产生γ-干扰素的能力。这些儿童既往无VL病史，基于利什曼原虫血清学转换被认为感染了恰加斯利什曼原虫。通过放射免疫分析法测定淋巴细胞培养上清液（3×10⁶/ml）在PHA（终浓度1:10）和恰加斯利什曼原虫抗原（10μg/ml）刺激下的γ干扰素水平。血清学转换儿童的淋巴细胞在PHA（178±151 U/ml）和恰加斯利什曼原虫（47±77 U/ml）刺激下产生的γ-干扰素明显高于内脏利什曼病患者。为了进行临床随访，这18名血清学转换儿童被分为三组：无症状感染（N = 4）；自愈性亚临床疾病（N = 9），以及进展为VL的亚临床感染（N = 5）。无症状或亚临床感染儿童的γ干扰素水平（65±85 U/ml）明显高于进展为VL的儿童（9±6 U/ml）（P＜0.003）。数据表明γ干扰素水平与利什曼原虫感染的临床病程之间存在关联。
