OBJECTIVETo seek differentially expressed serum proteins in recovered SARS patients complicating avascular necrosis of femoral head (AVNFH).

METHODS2-DE and MALDI-TOF MS were used to study the comparative serum proteomics among female SARS AVNFH group, female SARS non-AVNFH group and female healthy group. ELISA method was used to detect serum amyloid P component in individual serum; specificity and sensitivity of serum amyloid P component were analyzed.

RESULTSAverage protein points on 2-DE of 3 groups were 632 +/- 28, 671 +/- 55, 688 +/- 42 respectively, and the matching rate of protein points was ranged from 85% to 95%; eighteen differentially expressed proteins were discovered including transthyretin, serpin peptidase inhibitor, alpha-1-antitrypsin precursor, serum amyloid P components, etc. Compared to healthy group and SARS non-AVNFH group, transthyretin, C4B3, fibrinogen gamma, apolipoprotein L, apolipoprotein A-IV precursor, albumin and prealbumin showed lower expression, inversely serpin peptidase inhibitor, alpha-1-antitrypsin precursor and serum amyloid P components showed higher expression in serum in the SARS AVNFH necrosis group. The serum amyloid P component in 3 groups were 0.54 +/- 0.30 ng/ml, 0.83 +/- 0.39 ng/ml, 1.21 +/- 0.29 ng/ml respectively. The areas under the ROC curve on serum amyloid P component was 0.854, the specificity was 77.8% and the sensitivity was 85.2%.

CONCLUSIONThere were differentially expressed serum proteins in three groups. Serum amyloid P components might be one of the potential biomarkers in serum of recovered SARS patients complicating avascular necrosis of femoral head.