J Clin Transl Sci. 2019 Sep 26;3(6):332-343. doi: 10.1017/cts.2019.410. eCollection 2019 Dec. Application of volumetric absorptive microsampling (VAMS) to measure multidimensional anti-influenza IgG antibodies by the mPlex-Flu assay.

Wang J1, Li D2, Wiltse A1, Emo J1, Hilchey SP1, Zand MS1,2.
Author information

1 Department of Medicine, Division of Nephrology, University of Rochester Medical Center, Rochester, NY, USA. 2 Clinical and Translational Science Institute, University of Rochester Medical Center, Rochester, NY, USA.

Abstract

Introduction: Recently, volumetric absorptive microsampling (VAMS) has been used for accurate sampling of a fixed peripheral blood volume (10 ?L) on a volumetric swab, and long-term sample storage. The mPlex-Flu assay is a novel, high-throughput assay that simultaneously measures the concentration of antibodies against the hemagglutinin (HA) proteins from multiple influenza virus strains with ≤5 ?L of serum. Here we describe combining these two methods to measure multidimensional anti-influenza IgG activity in whole blood samples collected by a finger stick and VAMS, with correction for serum volume based on simultaneous hemoglobin measurement. Methods: We compared capillary blood samples obtained from a finger stick using a VAMS device with serum samples collected by traditional phlebotomy from 20 subjects, with the influenza antibody profiles measured by the mPlex-Flu assay. Results: We found that results with the two sampling methods were highly correlated within subjects and across all influenza strains (mean R 2 = 0.9470). Adjustment for serum volume, based on hemaglobin measurement, was used to estimate serum volume of samples and improved the accuracy. IgG measurements were stable over 3 weeks when VAMS samples were stored at room temperature or transported using a variety of shipping methods. Additionally, when volunteers performed finger-stick VAMS at-home by themselves, the comparison results of anti-HA antibody concentrations were highly consistent with sampling performed by study personnel on-site (R 2 = 0.9496). Conclusions: This novel approach can provide a simple, accurate, and low-cost means for monitoring the IgG anti-influenza HA antibody responses in large population studies and clinical trials.
? The Association for Clinical and Translational Science 2019.


KEYWORDS:

Volumetric absorptive microsampling (VAMS); clinical influenza vaccine studies; immunity assay; influenza A virus antibodies; mPlex-Flu assay

PMID: 31827907 PMCID: PMC6885997 DOI: 10.1017/cts.2019.410