The Effects Of CysLTs,IL-10,TNF-α On Mycoplasma Pneumonia In Children

Mycoplasma pneumoniae is a kind of atypical pathogenic bacteria that could cause respiratory infection of human being, it is a microorganism between virus and bacterium. There are cell membrane and cytoplasm antigen, but no cell wall. Its major cell membrane antigen is glycolipid antigen. There is an especially structure at the top of mycoplasma pneumoniae. The structure plays an important role not only in adhere, gliding and cell division, but also as an important immunogen, evoking intensive immunological response of human body. Through spatter and contraction for a long time, mycoplasma pneumoniae could spread. When the pathogen enters respiratory tract, it adheres to epithelial cell closely which causes damage to epithelium mucosae and presents symptoms. At the same time acting as an external antigen it can stimulate body immune system to produce immune response and induce the disturbance of cellular immunity and humoral immunity. So up to now we consider the infection of mycoplasma pneumoniae as a systemic disease which involves immunologic mechanism. Mycoplasma pneumoniae pneumonia is an atypical primarily pneumonia causes by mycoplasma pneumoniae. It occurs mainly in school age children and sapling. The clinical manifestation of MPP generally shows long-term fever, irritable cough which is a distinguished feature of MPP. Physical sign in bellows is unobvious, but the change of imageology is notable. The incidence rate of MPP is increasing evidently in recent years. The age of onset is shifting to an earlier time apparently. MPP has been one of the most common pneumonia in school age children and teenagers, and the rate in infants and young children is increasing. Because short of specific diagnosis criteria in early period, the clinical diagnosis is basing on the typical clinical manifestation and radiographic findings. It can not only cause the respiratory injury, but also induce the extrapulmonary manifestation, such as nervous system, hematological system, cardiovascular system, digestive system, urinary system, muscle and arthrosis. So it was considered that MPP is not only an infectious disease caused by the invasion of pathogen, but a systemic disease which immune system participates. Children of MPP always manifest chronic cough, repeated wheezing and many extra- pulmonary complication, so MPP has caused great attention of pediatrician. Untill now the mechanism of MPP has not been clarified, but it is clearly that cytokine plays an important role in immunological reaction, inflammatory reaction and immunologic injury. So the study of cytokine in MPP and its application has been an attractive topic for the scholar out and in.The body immune system is a huge and complicated network, all kinds of immunocytes and immune factors interact and restrict each other, influence the turnover of disease. Cytokines play an important role in the process. Studies indicate that the more severe of a MPP patient ,s condition, the more significant in his change of cytokines. More and more studies shows that many cytokines participate in the pathogenesis of MPP, such as IL-2, NO, TNF, IL-4, IL-6, sIL-6R, IFN-γ, sIL-2R and IL-18. TNF-αis a polypeptide regulatory factor, secreted by mononuclear macrophage, it has many biologic activities. It can stimulate mononuclear cell and endothelial cell to secrete cytokines, induce neutrophil to aggregate, phagocytize and kill the pathogen, drive the inflammatory reaction. The effectiveness of TNF-αis changing with its concentration in organism. If the concentration is too high, it can induce many pathological process of inflammatory reaction, lead to severe inflammation, and organ disfunction. IL-10 is a kind of protein secreted by Th2, which could inhibit Th1. Its main biological function is to restrain the inflammation, regulate the differentiation and proliferation of immune cells. It protects our body from the damage of excessive inflammatory reaction. As a kind of powerful mediators of inflammation, CysLTs play an important role in many component elements in bronchial asthma. Nowadays, as more and more children of MPP get chronic cough and wheezing, scholars pay more attention to the relationship between CysLTs and MPP.To approach the effect of these three cytokines mentioned above in MPP, and reveal the immunological pathogenesis of MPP, we compared the blood serum level of TNF-α, IL-10 and CysLTs in four groups below using ELISA method. Group one, 40 children with MPP who were in acute stage. Group two, 23 children who were in convalescence stage of MPP. Group three, 20 children with bronchopneumonia excluded the infection of MP. Group four, 20 healthy children. The results showed that compared with the healthy children, the blood serum level of CysLTs and IL-10 changed significantly in children of MPP, while level of TNF-αdid not have an evident change. This study suggests that, CysLTs and IL-10 could play a part in the pathogenesis of MPP, they probably participate in the primary damage in lung, and complications extra-pulmonary. While about the relationship between TNF-αand MPP, needs further study.For the treatment in children, we mainly use macrolides, this kind of medicine produce an effect of anti-infection through inhibiting the biosynthesis of protein, but drug resistant strain has appeared. So simply anti-infection could not provide an effective therapy. Clinically for the severe cases, using glucocorticoid and gamma globulin, has received a fine therapeutic effect. Cytokines play an important role in the pathogenesis of MPP. Whether could we find a new therapeutic method aiming directly at these cytokines? The level of CysLTs rises in children with MPP, we have applied CysLTs-receptor antagomists to children accompanied with wheezing, and get a significant effect. Our study also shows, the level of IL-10 descends, it needs further research to confirm if can we get a therapeutic effect through supplying IL-10.