New Publication in Analytical and Bioanalytical Chemistry
Bärwinkel, C.; Petzold, A.; Lück, C.; Petzold, M.; Seidel, M.
Analytical and Bioanalytical Chemistry, 2025, https://doi.org/10.1007/s00216-025-06194-3.
Abstract
Chemiluminescence imaging of sandwich microarray immunoassay (CL-SMIA) is a simple and rapid method for antibody-based serotyping of pathogens like L. pneumophila which is important to identify even outbreak-associated subtypes like L. pneumophila Sg 1 subtype Philadelphia. The CL image pattern can be interpreted by a decision path similar to the well-known `Dresden Panel´, which is typically performed via indirect ELISA. New antibodies needed to be characterized for the so-called `LegioTyper panel´ as capturing antibodies to perform the flow-based CL-SMIA. Following was achieved for the Legiotyper principle: i.) minimizing the costs for antibody microarrays by manufacturing Jeffamine-2003-coated polycarbonate sheets, ii.) optimized automated test procedure which is able to perform the CL-SMIA in 34 min, iii.) covalent immobilization of cAb using a microdispensing buffer which contains reactions for stabilizing and bioconjugation of cAb. Nine mAb and one polyclonal Ab (pAb) were characterized regarding the selectivity to L. pneumophila Sg 1 and additionally to the virulence-associated subtypes Knoxville, France, Allentown, Benidorm, and Philadelphia (all Pontiac group), OLDA, Oxford, Bellingham, Heysham, and Camperdown (all Non-Pontiac group). We could show that by using the LegioTyper it is possible to differentiate between L. pneumophila Sg1 and non-Sg1 and between Pontiac and non-Pontiac strains. Additionally, the subtyping with the `LegioTyper Panel´ was possible for most of the outbreak-associated subtypes. Overall, our study showed that the LegioTyper principle can be used for rapid antibody-based subtyping of L. pneumophila Sg 1 after cultivation. It is an alternative to indirect ELISA or qPCR, which are more labor- and cost intensive, and the automation is more complicated.