Generation of Rat Monoclonal Antibody to Detect Hydrogen Sulfide and Polysulfides in Biological Samples

Hydrogen sulfide (H(2)S) is endogenously produced by enzymes and via reactive persulfide/polysulfide degradation; it participates in a variety of biological processes under physiological and pathological conditions. H(2)S levels in biological fluids, such as plasma and serum, are correlated with the severity of various diseases. Therefore, development of a simple and selective H(2)S measurement method would be advantageous. This study aimed to generate antibodies specifically recognizing H(2)S derivatives and develop a colorimetric immunoassay for measuring H(2)S in biological samples. We used N-ethylmaleimide (NEM) as an H(2)S detection agent that forms a stable bis-S-adduct (NEM-S-NEM). We also prepared bis-S-heteroadduct with 3-maleimidopropionic acid, which, in conjugation with bovine serum albumin, was to immunize Japanese white rabbits and Wistar rats to enable generation of polyclonal and monoclonal antibodies, respectively. The generated antibodies were evaluated by competitive enzyme-linked immunosorbent assay. We could obtain two stable hybridoma cell lines producing monoclonal antibodies specific for NEM-S-NEM. By immunoassay with the monoclonal antibody, the H(2)S level in mouse plasma was determined as 0.2 μM, which was identical to the level detected by mass spectrometry. Taken together, these monoclonal antibodies can be a useful tool for a simple and highly selective immunoassay to detect H(2)S in biological samples.