ABSTRACT
<p><b>OBJECTIVE</b>Interleukin-27 (IL-27) has been reported to reduce the levels of interleukin-17 (IL-17) and alleviate the severity of experimental autoimmune myocarditis. IL-17, an important tissue-protective cytokine in viral myocarditis (VMC), has been reported to increase synovial expression of IL-27 in rheumatoid arthritis. However, the influence of IL-17 on IL-27 expression in murine model of VMC remains unknown.</p><p><b>METHODS</b>Wild-type (WT) and IL-17A-deficient (IL-17A(-/-)) mice on the BALB/c background were intraperitoneally (i.p) injected with coxsackievirus B3 (CVB3) for establishing VMC models. Cardiac tissue was obtained on day 7 after CVB3 injection. Myocardial histopathologic changes were observed by hematoxylin-eosin (HE) stained myocardial sections.Expression of IL-27 in heart and serum was measured by real-time reverse transcription-polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA), respectively. Furthermore, splenic lymphocytes and peritoneal macrophages were purified 1 week after injection from WT mice.Isolated lymphocytes were cultured in the presence of different concentrations (0 and 25 ng/ml) of recombinant IL-17 (rIL-17) for 24 h. Macrophages were cultured with different concentrations of rIL-17 (0 and 10 ng/ml) for 48 h.IL-27 mRNA expression of cultured cells was assayed by RT-PCR, and their protein level in the culture supernatant was measured by ELISA.</p><p><b>RESULTS</b>Compared with WT mice, significantly less cardiac inflammation was evidenced in the heart of IL-17A-/- mice (0.9 ± 0.3 vs.1.9 ± 0.5) , relative cardiac IL-27 p28 mRNA expressions (1.11 ± 0.24 vs.3.1 ± 0.8) and serum IL-27 protein[(72 ± 18) pg/ml vs.(95 ± 25) pg/ml] were also significantly lower in IL-17A-/- mice (all P < 0.05).In the culture lymphocytes, the relative mRNA (1.02 ± 0.13 vs.1.32 ± 0.21) and protein [(49 ± 9) pg/ml vs.(52 ± 11) pg/ml]expressions of IL-27 p28 and were similar post treatment with 0 and 25 ng/ml rIL-17 (all P > 0.05). Compared with 0 ng/ml rIL-17 culture with macrophages, higher relative mRNA (8.5 ± 3.1 vs.2.2 ± 0.7) and protein [(368 ± 95) pg/ml vs.(150 ± 38) pg/ml] expressions of IL-27 p28 were detected in 10 ng/ml rIL-17 group (all P < 0.05).</p><p><b>CONCLUSION</b>Our data indicates that cytokine IL-17 may contribute to the secretion of IL-27 in VMC mice.Furthermore, macrophages but not lymphocytes may be the important IL-27-producing immune cells and major target cells for IL-17. Thus,IL-27 and IL-17 might be actively involved in the pathogenesis of VMC.</p>
Subject(s)
Animals , Male , Mice , Coxsackievirus Infections , Allergy and Immunology , Metabolism , Disease Models, Animal , Interleukin-17 , Allergy and Immunology , Interleukin-27 , Metabolism , Macrophages , Metabolism , Mice, Inbred BALB C , Myocarditis , Allergy and Immunology , MetabolismABSTRACT
Objective To explore the heredity susceptibility of children to Kawasaki disease (KD) through studying expression and genomic density polymorphism of peripheral erythrocyte complement receptor-1 (ECRI). Methods Thirty cases of KD patients and 28 cases of healthy children were included in this study. The rates of red blood cell (RBC)-C3bRR and RBC-ICR were detected by method described elsewhere. The ECR1 activity and genomic density polymorphism were detected by Hind Ⅲ restriction enzyme digestion polymerase chain reaction-restriction fragment length polymorphism. Results Rates of RBCoC3bRR of KD patients during the acute phase was significantly lower than that of the control group (P < 0.01), and remained lower than the control group during the recovering phase (P < 0.05). The rates of RBC-ICR were significantly higher in KD patients than that of the control group (P < 0.05). Frequencies of HL and LL genotypes of KD patients were more than those of the control group (P < 0.01). A significant difference was found in the frequency distribution of ECR1 genotype between the two groups (P < 0.01). L allele frequency in the patient group was higher than that in the control group. Conclusions Depressed RBC immune function in KD patients may be linked to the high frequency of L allele, which implies the genomic density polymorphism of ECR1 play an important role in determining susceptibility to Kawasaki disease. (J Clin Pediatr,2010,28(2):160-163)