Advances in understanding newer autoantibodies and their role as biomarkers in systemic lupus erythematosus

Microbead-based technologies in diagnostic autoantibody detection

BACKGROUND

There is a rapid proliferation of new technologies to identify a spectrum of autoantibodies in medical conditions that range from organ-specific autoimmune diseases to systemic rheumatic diseases. Although many laboratories have adopted high-throughput diagnostic platforms such as enzyme linked immunoassays (ELISA), other technologies such as microbead-based assays are emerging as an alternative diagnostic platform.

OBJECTIVE

To understand the performance and importance of bead based immunoassays in clinical diagnostics and therapeutics.

METHOD

Current literature was reviewed using the PubMed search engine combining keywords of immunoassay and Luminex, as well as a personal literature database. Included in the evaluation and commentary are bead-based assays such as addressable laser bead immunoassays and related magnetic bead assays.

CONCLUSIONS

Comparison with other conventional technologies has indicated that laser microbead immunoassays are reliable, accurate, cost-effective, highly sensitive and have rapid turn around time for results. While there are advantages to this diagnostic platform, there are challenges that must be addressed before wider acceptance or long-term use of this technology platform in the routine clinical diagnostic laboratory.

Challenges to the use of autoantibodies as predictors of disease onset, diagnosis and outcomes

Autoantibodies (AA) are a serological hallmark of most autoimmune diseases. In contrast to genetic markers that show a predisposition for disease development, certain AA serve as diagnostic biomarkers and classification criteria for a number of these conditions. The role of AA is still not clearly understood: some are pathogenic, some disease specific and others serve as predictors of disease outcome, but little is known about those that protect against disease or serve as signatures of the inciting agent of autoimmunity. Because of growing evidence that some AA antedate clinical diagnosis, significant effort is being spent on gathering evidence regarding their value as predictors of disease onset and outcome. Although many studies have shown that specific AA are detected in the pre-clinical phase and are biomarkers of increased risk of developing an autoimmune disease, they are currently not widely used to determine risk or as a pre-clinical screen. Additional prospective and retrospective studies are urgently needed to determine the precise risk of developing autoimmune disease in the presence of various AA. Such studies must be attended by the development of strategies for earlier diagnosis and novel therapeutic interventions of early disease.