Out of the Laboratory and Into the Field: Validation of Portable Cell Culture Protocols.

Abstract

Field-based research on inflammation and health is typically limited to baseline measures of circulating cytokines or acute-phase proteins, whereas laboratory-based studies can pursue a more dynamic approach with ex vivo cell culture methods. The laboratory infrastructure required for culturing leukocytes limits application in community-based settings, which in turn limits scientific understandings of how psychosocial, behavioral, and contextual factors influence the regulation of inflammation. We aim to address this gap by validating two "field-friendly" cell culture protocols, one using a small volume of venous whole blood and another using finger-stick capillary whole blood. We evaluated the performance of both protocols against a standard laboratory-based protocol using matched venous and capillary blood samples collected from young adults (n = 24). Samples were incubated with lipopolysaccharide and hydrocortisone, and the production of proinflammatory cytokines interleukin 1β, interleukin 6, and tumor necrosis factor α was measured in response. Comparisons indicate a high level of agreement in responses across the protocols and culture conditions. The overall correlation in results was 0.88 between the standard and small-volume protocols and 0.86 between the standard and capillary blood protocols. Repeatability for the small-volume and capillary blood protocols was high, with mean coefficients of variation across five replicates of 6.2% and 5.4%, respectively. These results demonstrate the feasibility of culturing cells and quantifying the inflammatory response to challenge outside the laboratory, with a wide range of potential applications in biobehavioral research in community-based and remote field settings.