Efficiency of oral fluid collection devices in extracting antibodies.

Introduction: To facilitate diagnoses, this study determined the efficacy of commercial oral fluid collection devices for their ability to recover three human immunoglobulin isotypes; immunoglobulin A (IgA), IgG, and IgM.

Methods: The sandwich enzyme-linked immunosorbent assay was used to determine antibody recovery from the following devices: (i) OraSure oral specimen collection device, (ii) saliva*sampler, (iii) ORALscreen collector, (iv) Dri-Angle, (v) no. 2 cotton roll, (vi) all-gauze sponges device, and (vii) DentaSwabs. For each isotype tested, the recovered eluate was compared with the concentration applied to the device. The performance of each device was determined at various antibody concentrations.

Results: Recovery of IgA from the saliva*sampler, ORALscreen collector, Dri-Angle and cotton roll was comparable to that seeded onto the device. When compared with the seeded IgG concentration, the mean concentration of antibody recovered by each product differed by approximately +/- 9 ng/ml. The average amount of IgM recovered by the cotton roll and all-gauze sponges device was approximately 29 and 39 ng/ml, respectively, less (P < 0.0001) than that seeded on the device. For all isotypes tested, the amount of antibody recovered from the device was dependent on the initial seeding concentration.

Conclusion: Collectively, these data suggest that the product used for specimen collection can affect retrieval of antibodies and potentially confound patient diagnosis.