Expressions Of IL-6, IL-2, SIgA, IFN-γ, CD3in Digestive System Of Rhesus Monkey Infected Streptococcus Pneumoniae

To study the pathopoiesis mechanism of streptococcus pneumoniae through mucosa immune system, this experiment is to detect the pathological change and expression change of IL-6, IL-2, sIgA, IFN-γ, CD3in liver, jejunum, cecum, stomach and esophago of rhesus monkey infected streptococcus pneumoniae spontaneously. Method:Obtaining three infected rhesus monkeys and normal ones respectively, after blooding and dissection, obtaining liver, jejunum, cecum, stomach and esophago from each animal. Then fixing, next embedding these organs by paraffin. Studying pathological change by H.E staining, detecting expression of IL-6, sIgA, IFN-y protein by immunohistochemistry staining and IL-6, IL-2, sIgA, IFN-y, CD3mRNA by in situ hybridization. Results:(1) H.E staining showed liver has haemorrhage, hepatocytes were necrotic, cells in mucous layer of gastrointestinal tract were widespread degenerated and necrotic, glandular organs had severe disorganization, lymphocytes were increased, there was no obvious change in esophago;(2)Immunohistochemistry results showed that compared with normal group, total area of IL-6protein positive cells was increased in infected group significantly (p<0.05); IFN-y protein positive cells were increased very significantly in liver and jejunum (p<0.01), other organs saw no obvious increase; sIgA protein positive cells were decreased significantly in jejunum (p<0.05), while there were no significant decrease in other organs (p>0.05);(3) In situ hybridization results of total area of positive cells change in infected group (compared with normal ones):IL-6mRNA expression increased significantly in liver, cecum and stomach (p<0.05); IL-2mRNA decreased in liver, cecum and esophago significantly (p<0.05), extremely obvious in jejunum (p<0.01); IFN-y mRNA saw significant increase in jejunum(p<0.05), while CD3mRNA decreased very significantly in jejunum (p<0.01) and in cecum the decrease was significant (p<0.05); sIgA mRNA decreased significantly in jejunum, cecum and stomach; the rest organs did not show obvious change.(4) Immunohistochemistry results show the OD change in infected group compared with normal ones:OD of IL-6proteins in cecum and stomach increased significantly(p<0.05), and in jejunum was extreme significant (p<0.01), but decreased in liver; IFN-y proteins expression cells had a significant increase in liver and stomach(p<0.05), and extreme significant in jejunum (p<0.01); no obvious change showed in sIgA expression cells.(5) In situ hybridization results about OD change in infected group compared with normal group:OD of IL-6mRNA positive cells increased significant in cecum (p<0.05), and in jejunum was extreme significant (p<0.01), while OD decreased in liver and not obvious; IL-2mRNA OD increased in liver, cecum and esophago and decreased in other organs, but not obvious; OD of IFN-y mRNA positive cells increased significant in liver, jejunum and stomach(p<0.05), and extreme significant in esophago(p<0.01); slgA mRNA expression cells’OD saw similar extreme increase in esophago (p<0.01); CD3mRNA OD increased in liver, but decreased in other organs; there were no obvious change in other organs(p>0.05).(6) Positive reaction was shown in the cytoplasm in granular form both in immunohistochemistry and in situ hybridization results. Positive cells were mainly distributed in the mucous layer of gastrointestinal tract and esophago, liver cell cord and some stll can be seen in the blood vessel and connective tissues. Positivel cells are mostly inflammatory cells, endothelial cells and hepatocytes, some glandular cells and intramuscular connective tissue showed positive reaction also.Conclusion:Results show that after Streptococcus pneumoniae infection, the cellular immunity of gastrointestinal tract will be strengthen, while humoral immunity level reduced to some extent. According the above results, it may be conclude that the cellular immunity of gastrointestinal tract is helpful for the clearance of Streptococcus pneumoniae, expression change of cytokines and antibody are concerned with the pathopoiesia mechanism of Streptococcus pneumoniae, regulation of their expression may provide new methods to develop vaccines or medicine targets.