| Coxsackievirus is a member of the genus Enterovirus in the family Picornaviridae. It can cause many diseases, such as respiratory infection, myocarditis, pericarditis, neurological disorders and so on. It even can lead to the death of newborn. At present, epidemiological monitor is the principal approach to control this disease. There's no useful vaccine to prevent coxsakievirus infection.In this experiment, we confirmed that High hydrostatic pressure( HHP) could make the pathogenicity of virus decreased or disappeared, but reserve important antigen determinant of virus. The immunogenicity of virus does not decrease. 1,CB3V has strong resistance to pressure. In 680Mpa, virus still remain virulence, above 700Mpa, completely inactivated. In lower pressure, CB3V can only be inactivated by entending time, for example, pressure at 600Mpa for 1h can not reduce virulence, and for more than 5h, can inactivate virus completely. The reason of CB3V resistant to pressure is : 1) CB3V is non-enveloped particles. Envelope comes from membrane of host cells and is sensitive to physical and chemical factors. CB3V is resistance to pressure, this result is coincidented with other laboratory[2]. 2) CB3V is extremely small, only 23-30nm,D.W. Bradley [37] et al indicated that bigger virus is more sensitive to pressure. 2,Study suggested that the immogenicity of CB3V treated by HHP didn't change.Body immune defence system include non-specific immunity and specific immunity. The former is mediated by macrophage cells and the later is mediated by lymphocytes. Specific immunity can be divided into humoral and cellular immunity.Non-specific immunity is an important component of body immune system. Phagocytosis ability of macrophage is one marker to measure the function of non-specific immunity. CB3V attenuated or inactivated by pressure can reinforce the phagocytosis ability of macrophage cells of mouse. There's no significant difference compared with the CB3V treated by heat. In addition, CB3V treated by pressure can promote the synthesis and release of PGE2.It has been reported that the reinforcement of macrophage ability can accelerate the release of PGE2.Goodwin believed that PGE2 could facilitate the differentiation and maturation of lymphocyte, and had obvious function of immunoregulation. So we suppose that CB3V attenuated or inactivated by pressure can regulate the immune function of mouse through stimulating PGE2 release. Then the increased immune function protect the body far away from the attack of pathogen microorganism, and inhibit immune damage caused by excessive immune response.The result of ELISA and micro neutralization test indicated that CB3V treated by pressure increased the function of lymphocyte B. Humoral immunity mediated by antibody can prevent extracellular infection and control the following symptom. Antibody's major function is to neutralize and clear away the pathogen microorganism and toxin produced by them. Lymphocyte B can produce different kinds of antibody, such as IgM, IgA, IgE, IgG, and response to different antigen. Immune mouse with virus treated by pressure. There are notable difference in dose of antibody between the immunized group and normal group (P<0.05).The titer of antybody are 1:8000. T lymphocyte transformation test evidenced that CB3V treated by pressure could accelerate specific T lymphocyte transformation. The transformation efficiency of the immunized group by treated virus is higher than normal group. This implied that the cellular immunity of the mouse was intensified. The reason for the higher transformation efficiency is supposed that : 1) nucleic acid of CB3V is +ssRNA, have infection ability. Infectivity of naked RNA is 1/100000 compared with virus particle. It is evident that naked RNA is extremely sensitive to RNA enzyme (<0.01μg/ml). Integrety of RNA is necessary for its infection ability. If there is a little bit trip off or brokened, its infection ability is destructed, no matter it happened in the virus particle or free RNA. The coat of...
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