Cytomegalovirus antibodies in dried blood spots: a minimally invasive method for assessing stress, immune function, and aging

Analysis of CMV in dried blood spot samples (DBS) was based on modifications of a commercially available protocol for quantifying CMV antibodies in serum or plasma. The method was evaluated through analysis of precision, reliability, linearity, and correlation between matched serum and DBS samples collected from 75 volunteers. Correlation between DBS and plasma values was linear and high (Pearson correlation R = .96), and precision, reliability, and linearity of the DBS assay were within acceptable ranges.The validity of a DBS assay for CMV antibodies will enable its inclusion in population-based surveys and other studies collecting DBS samples in non-clinical settings, increasing scientific understanding of the interaction of social and biological stress and immune function.Immune system decline is one of the hallmarks of aging. Age-associated alterations in systemic immunity, referred to as 'immunosenescence', are thought to contribute to the increased incidence and severity of infectious disease in older persons, as well as decreased response to vaccination [1,2]. Increasing evidence suggests that the persistent herpesvirus cytomegalovirus (CMV) plays an important role in human immunosenescence, meriting special attention in studies designed to understand stress, immune function, and health[3]. This paper describes and validates a minimally invasive method for assessing antibodies against CMV in dried whole blood spot samples. The collection of dried blood spots (DBS)-drops of whole blood on filter paper from a single finger prick-has recently become a popular minimally invasive technique for collecting biomarkers in population surveys [4]. Since most standard laboratory protocols require serum or plasma, assay protocols must be developed specifically for DBS and validated for accuracy, precision, reliability, and limits of detection. This validation of a dried-blood spot assay for CMV antibodies will facilitate its broad inclusion in population-based surveys and