Multiplex Point-of-Care Tests for the Determination of Antibodies after Acellular Pertussis Vaccination

Abstract

Most of the current serological diagnosis of pertussis is based on pertussis toxin (PT) IgG antibodies and does not differentiate between vaccination and infection-induced antibodies. PT is included in all of acellular pertussis vaccines available in the world. Multiplex testing of non-vaccine antigen-related antibodies has the potential to improve the diagnostic outcome of these assays. In this study, we developed a quantitatively spatial multiplex lateral flow immunoassay (LFIA) for the detection of IgG antibodies directed against PT, pertactin (PRN), and filamentous hemagglutinin (FHA). The assay was evaluated with serum samples with varying anti-PT, anti-PRN, and anti-FHA IgG levels and the result was compared to those obtained with standardized ELISA. The developed assay showed good specificity with PT and PRN antibodies and semiquantification throughout the antigen combinations. This exploratory study indicates that the multiplex LFIA is specific and sensitive, and a similar test platform with alternative antigens could be suitable for new type of pertussis serology.

Simultaneous Determination of Antibodies to Pertussis Toxin and Adenylate Cyclase Toxin Improves Serological Diagnosis of Pertussis

“…This study demonstrated that the multiplex measurement of PT and ACT antibodies can improve the serological diagnosis of pertussis. In combination with a rapid and easy-to-perform multiplex platform with lateral flow assays [ 12 , 20 ], serological testing could be performed very flexibly and even within a short period from pertussis vaccination. The test would be of particular use for serological diagnosis concerning children and adolescents who have recently received a booster vaccine, and in cases when the vaccination background of a patient is uncertain with regard to personal recalling or knowledge, or due to a lack of extensive records of the timing of the latest vaccination.…”

“…The preparation of the strips and the test procedure were done similar to Knuutila et al with the following modifications [ 12 ]: 1000 ng/cm of ACT was used as the second test line, between native PT (GlaxoSmithKline Biologicals, S.A., Rixensart, Belgium) and the control line ( Figure 1 and Figure S1 ). 06/142 sera, in-house PT-positive and PT-negative controls were included for each run.…”

“…A combinatory antibody test with well-established quantitative cutoff values for anti-PT antibodies to demonstrate specificity [ 11 ], and with ACT to differentiate between infection and recent vaccination, could improve pertussis diagnostics [ 9 , 10 ]. We earlier reported a quantitative and rapid lateral flow (LF) platform, based on immunochromatography, for multiplex determination of antibody response to PT, PRN, and FHA antigens without the complexity of common laboratory practicalities [ 12 ]. The developed multiplex LF platform was further used in this study to measure anti-PT and anti-ACT antibody responses from patients, healthy controls, and acellular pertussis vaccine recipients.…”

Oral fluid-based lateral flow point-of-care assays for pertussis serology

“…Another natural source of deviation between the assays was derived from the choice of a label in the LF assay, as the protein A conjugate also binds to IgA and IgM antibodies [27]. This will potentially reduce the correlation between the two assays because the oral fluid ELISA is designed to measure only IgG.…”

“…All samples were tested at least in duplicate. After absorbing the sample, 6×10 7 protein A (#RL240425; Thermo Fisher Scientific) label, conjugated with activated fluoro-Max carboxyl modified microparticles, containing Eu-nanoparticles (diameter 99 nm; Thermo Fisher Scientific) [27] were applied to the LF strips in dipstick-format with 60 µl of HEPES buffer. Protein A binds to various mammalian Fc portions of immunoglobulins, including anti-human IgA, IgG and IgM.…”