ABSTRACT
Objective To analyze the biological characteristics of clinical isolates of coxsackievir-us A6 (CVA6), a pathogen of hand,foot and mouth disease (HFMD), and to provide reference for vaccine development. Methods CVA6 strains were isolated from 21 stool and throat swab specimens of patients with HFMD in Yunnan Province and then identified. Their growth characteristics, plaque morphology and virulence to suckling mice were analyzed. Results Five CVA6 strains, named CVA6-129, CVA6-113, CVA6-57, CVA6-94 and CVA6-162, were isolated and all belonged to D3 subtype. Only the CVA6-129 strain could proliferate rapidly in Vero and KMB17 cells and the proliferation peaked 30 h after inoculation. The infectious titer of the CVA6-129 strain was 7. 54 lgCCID50 (50％ cell culture infective dose) / ml in KMB17 cells. Different morphologies of plaques were formed by the CVA6-129 strain in Vero and KMB17 cells at the same time points, which were small and round with clear edges in Vero cells, and large and irregular with blurry edges in KMB17 cells. Suckling mice were susceptible to CVA6 via intramuscular and intraperito-neal injection. The most common symptoms in infected suckling mice were reduced mobility, hind limb pa-ralysis and quadriplegia. CVA6 infection could result in death in severe cases. Conclusions This study isolated five CVA6 strains from a number of clinical samples of suspected HFMD cases, of which the CVA6-129 strain showed potential as a vaccine candidate.
ABSTRACT
This paper was aimed to study the effect of Qing-Chang Wen-Zhong (QCWZ) decoction on interferon gamma induced protein 10 (IP10) in colon tissues of rats with ulcerative colitis (UC).The UC model was induced using 4.5％ DSS added to distilled water for 7 days.At the same time,low-,medium-and high-dose of QCWZ decoction and mesalazine was given by gavage route daily.Then,the rats were killed and the colon tissues were taken.Expression level of interleukin-1 alpha (IL-1α),IL-1β,IL-6,tumor necrosis factor alpha (TNF-α) and interferon gamma (INF-γ) in colon were detected by Elisa assay.The expression and distribution of IP10 protein were detected by immunohistochemistry (IHC).The results showed that compared with the normal group,inflammatory factors (IL-1α,IL-1β,IL-6,TNF-α,INF-γ) and IP10 expression level in DSS-induced UC rats were significantly increased.After 7 days of intervention,inflammatory factors (IL-1α,IL-1β,IL-6,TNF-α,INF-γ) and IP10 decreased significantly (p＜0.01,p＜0.05).It was concluded that QCWZ decoction may down-regulate the expression of IP 10 and inflammatory factors (IL-1α,IL-1β,IL-6,TNF-α,INF-γ),and then inhibit intestinal inflammation and repair intestinal mucosal damage,so as to achieve the purpose of UC treatment.
ABSTRACT
Objective To evaluate the immune effects of bivalent inactivated rotavirus vaccine (IRV) and investigate the viability of development of bivalent IRV.Methods Firstly,bivalent IRV was prepared by mixing G1 IRV and G3 IRV with equal amount,G1 IRV and G3 IRV as monovalent control,PBS as negative control.Secondly,those vaccines were vaccinated to the mice by intramuscular injection.Then,to evaluate the immune effects of bivalent IRV,the levels of serum or fecal rotavirus specific IgG and IgA were assessed by ELISA,the levels of serum neutralized antibody were measured by microneutralization assay,the number of IFN-γ or IL-4 secreting cells were analyzed by ELISPOT assay.Results Compared to negative control group,bivalent IRV induced the higher levels of serum and fecal G1 and G3 rotavirus specific antibody.It was found that there were no significant differences for the levels of serum IgG and IgA,fecal IgG and IgA,serum neutralized antibody between induced by bivalent IRV and induced by G1 type monovalent vaccines ; but there were significantly increase for the levels of serum IgG (t =2.691,P＜0.05) and serum neutralized antibody (t =2.561,P＜0.05) between induced by bivalent IRV and induced by G3 monovalent vaccines,there were no significant differences for other antibodies between induced by bivalent IRV and induced by G3 monovalent vaccines.At the same time,compared to negative control group,bivalent IRV induced significantly increase in the number of IFN-γ or IL-4 secreting cells in spleen lymphocytes.It was found that there were no significant differences for the number of IFN-γ or IL-4 secreting cells stimulated by G1 rotavirus between bivalent IRV and G1 monovalent vaccines; but there were significantly increase for the number of IL-4 secreting cells (t =2.327,P＜0.05) stimulated by G3 rotavirus between bivalent IRV and G3 monovalent vaccines,there were no significant differences for the number of IFN-γ secreting cells stimulated by G3 rotavirus between bivalent IRV and G3 type monovalent vaccines.Conclusion The bivalent IRV can induce effective immune response,in which there were no inhibitory interference between the components of bivalent IRV,which provided the experimental basis for the development of bivalent IRV.