INCREASED EXPRESSION OF HDJ-2 (HEAT-SHOCK-PROTEIN 40) AND HEAT-SHOCK-PROTEIN-70 IN BIOPSY SPECIMENS OF TRANSPLANTED HUMAN LUNGS

Background: Heat shock proteins are expressed during several forms of stress and inflammation. This study was done to determine whether the expression of heat shock protein HDJ-2 (heat shock protein 40), heat s hock protein 60, and heat shock protein 70 are increased during reject ion in human pulmonary allografts. Methods: Thirty-five transbronchial biopsy specimens were obtained from adult lung transplant recipients. Histologic analysis and assessment of heat shock protein HDJ-2, heat shock protein 60, and heat shock protein 70 mRNA expression was perfor med. Total RNA was extracted, reverse transcribed, and amplified by po lymerase chain reaction with oligonucleotide primers specific for the heat shock proteins. The identity of the amplified message was verifie d by Southern blot and slot blot analysis. Results: The expression of heat shock protein HDJ-2 was significantly higher in samples from lung transplant recipients undergoing rejection when compared with recipie nts without rejection or infection. Heat shock protein 70 expression w as also increased in rejection. Expression of heat shock protein 60 di d not show any increase in recipients with no evidence of rejection an d infection or transplant recipients with rejection or infection. Seri al analysis of heat shock protein HDJ-2 and heat shock protein 70 obta ined in biopsy specimens during and after rejection showed a decrease of heat shock protein HDJ-2 and heat shock protein 70 expression after resolution of lung rejection. Conclusion: Our data demonstrate that t he expression of heat shock protein HDJ-2 and heat shock protein 70 in creases during lung rejection. However, only heat shock protein HDJ-2 was able to differentiate between rejection and infection. Measurement of heat shock protein HDJ-2 in transbronchial biopsy specimens may as sist in the differential diagnosis between rejection and infection in lung transplant recipients.