Serodiagnosis of infectious diseases with antigen microarrays

Aims: To generate protein microarrays by printing microbial antigens on slides to enable the simultaneous determination in human sera of antibodies directed against Toxoplasma gondii, rubella virus, cytomegalovirus and herpes simplex virus (HSV) types 1 and 2. Methods and Results: Antigens were printed on activated glass slides using high-speed robotics. The slides were incubated with serum samples and subsequently with fluorescently labelled secondary antibodies. Human IgG and IgM bound to the printed antigens were detected using confocal scanning microscopy and quantified with internal calibration curves. The microarray assay could detect as little as 0Æ5 pg of both IgG and IgM bound onto the glass surface. Precision profiles ranged from 1Æ7 to 18Æ5% for all the antigens. Microarrays and commercial ELISAs were utilized to detect serum antibodies against the ToRCH antigens in a panel of characterized human sera. Overall >80% concordance was obtained between microarray and ELISA kits in the classification of sera. Conclusions: These results indicate that the microarray is a suitable assay format for the serodiagnosis of infectious diseases. Significance and Impact of Study: Antigen microarrays can be optimized for clinical use, their performance is equivalent to ELISA but they offer significant advantages in throughput, convenience and cost.