下呼吸道感染患儿外周血单个核细胞呼吸道合胞病毒感染的研究

为探讨呼吸道合胞病毒（ＲＳＶ）对外周血单个核细胞（ＰＢＭＣ）的感染情况及感染后细胞免疫的变化，采用免疫组化法对１８例ＲＳＶ性急性下呼吸道感染患儿ＰＢＭＣ内ＲＳＶ及其Ａ、Ｂ亚型抗原进行了检测；采用ＡＰＡＡＰ法、ＭＴＴ比色法和ＥＬＩＳＡ法对Ｔ细胞亚群及Ｔ细胞表面白细胞介素２受体表达、ＰＢＭＣ培养上清液白细胞介素２（ＩＬ－２）活性和可溶性ＩＬ－２受体水平进行了测定。结果显示：１８例ＲＳＶ感染患儿中７例ＰＢＭＣ内可检测到ＲＳＶ抗原；１１例ＲＳＶＡ亚型感染者５例ＰＢＭＣ内均为ＲＳＶＡ亚型阳性，７例ＲＳＶＢ型感染者２例Ｂ亚型阳性；７例恢复期和１０例对照组患儿均为阴性；发病３天以内ＰＢＭＣ中ＲＳＶ抗原阳性者多于３天以后（Ｐ＜０．０５）。ＲＳＶ感染组ＰＢＭＣ内ＲＳＶ抗原阳性者，ＣＤ４细胞比率和ＩＬ－２水平均低于阴性者（ｔ＝２．３８，２．４０，Ｐ值均＜０．０５）。提示：ＲＳＶ性急性下呼吸道感染患儿ＰＢＭＣ可被ＲＳＶ感染，可能由此加重免疫活性细胞损害，导致细胞免疫功能紊乱。

Respiratory syncytial virus infection of human mononuclear leukocytes in children with acute lower respiratory infection

To explore the cellular immune response to infection of peripheral blood mononuclear cells (PBMC) by respiratory syncytial virus (RSV), the authors detected RSV and A,B subgroups antigens, T lymphocyte subsets, interleukin 2 (IL 2) recepotr on T cell surface and IL 2 level in culture supernatants of PBMC from patients with acute lower respiraotry infection (ALRI) by using immunoperoxidase, APAAP and MTT colorimetric assay. Seven of the 18 cases with documented RSV infection showed expression of RSV antigens by circulating PBMC but no pathogens were detected in all 7 convalescent cases and 10 controls. A highly positive rate was found in PBMC of patients who were symptomatic for one to three days compaired to those for three to ten days ( P <0.05). Immunologic study showed that CD 4 cell percentage and IL 2 level were significantly lower in PBMC RSV positive cases than in negative cases ( t = 2.38 , 2.40, both P <0.05). These results suggest that PBMC of patients with RSV ALRI can be infected by RSV, which may result in more severe damage of immunologically active cells and cellular immunological disturbance.