OBJECTIVEThe aim of this study was to explore the roles and clinical significance of innate immune receptors and cytokine in children with measles.

METHODThe children with measles hospitalized in the department of infectious diseases, Children's Hospital of Fudan University during 2009-2011 were enrolled into measles group, while the healthy children examined in well baby clinic were enrolled into control group. The mRNA expression of TLR2/3/4/7, melanoma differentiation-associated gene-5 (MDA-5), retinoic acid-inducible gene I (RIG-I), IFN-α/β and IL-10 in peripheral blood mononuclear cells were detected by real-time PCR. The protein levels of IFN-α, IFN-β and IL-10 in plasma were measured using ELISA. SPSS 13.0 software was applied to analyze the difference between two groups.

RESULTData from a total of 98 patients in measles group and 59 children in control group were collected. The mRNA expressions of TLR2, MDA-5 and RIG-I had no statistical significance between two groups (P > 0.05, respectively). The relative mRNA expressions of TLR3, TLR4, TLR7 in measles group (2.25 ± 0.74, 2.05 ± 0.72, 2.12 ± 0.29) were significantly lower than those in control group (2.09 ± 0.78, 1.90 ± 0.75, 1.87 ± 0.68) (P < 0.01; respectively). Both IFN-α and IFN-β had significantly decreased mRNA expressions in measles patients (2.41 ± 1.31, 2.47 ± 1.26) compared with those in controls (2.22 ± 0.48, 2.35 ± 0.64)(P < 0.01 respectively); however, IL-10 mRNA levels significantly increased (2.49 ± 0.58 vs. 2.62 ± 0.95) (P < 0.001). The IL-10 levels in plasma in measles group were significantly higher during the whole period of fever [<5 d group: 29.89 (25.82-38.15) ng/L and ≥ 5 d group:34.55 (28.26-38.70) ng/L] than that in control group [25.15 (24.20-27.38) ng/L] (P < 0.05 respectively).

CONCLUSIONTLR3/4/7 mRNA expression was low in peripheral blood mononuclear cells of measles patients. Levels of IL-10 were significantly raised in the early stage after infection and lasted for a long time, and reduced IFN-α levels in plasma were associated with the fever durations of measles patients. These results indicated that multiple TLRs and cytokines may participate in the immune response after measles virus infection.