[Heat shock response in experimental acute middle ear bacterial infection].

OBJECTIVE

To investigate the association between bacteria antigen and inner ear antigen and effects of stress on the expression spectrum and level of the antigen bearing hsp70 related epitope.

METHODS

Use monoclonal antibody against mammiferous hsp70 to recognize the related antigens of Bacillus pyocyaneus, Bacillus proteus, Bacillus coli, Staphylococcus aureus and Klebsiella pneumoniae with modified western blotting. The expression level of hsp70 in unstressed guinea pig inner ear was tested. An animal model of middle ear acute infection by Klebsiella pneumoniae was established. The dynamic changes of mammiferous hsp70 epitope related proteins were tested with modified western blotting.

RESULTS

All the bacteria antigens recognized by anti-mammiferous hsp70 antibody were not of the hsp70 family and the expression level of hsp70 in normal guinea pig was extraordinarily low. Klebsiella pneumoniae expressed 70,000 dalton and 17,000 dalton hsp after its invasion into guinea pig middle ear. 70,000 dalton antigen expressed most intensely at 3rd day of invasion and then fell. 17,000 dalton antigen was expressed most intensely at 5th day of invasion and then fell. The expression of 70,000 dalton hsp was much weaker than 31,000 dalton hsp at acute periods of middle ear infection.

CONCLUSIONS

The elevated expression of hsp both in bacteria and inner ear during middle ear acute infection provides material base for immune impairment on inner ear induced by bacterial infection. The low molecular weight hsp may be involved in the inner ear autoimmune impairment.