Detection of anti-listeriolysin O for serodiagnosis of human listeriosis

Comparative efficacy of Internalin C-based peptide and listeriolysin O-based enzyme linked immunosorbent assays for serodiagnosis of listeric infection in goats

“…The purity of LLO was checked with SDS-PAGE while protein concentration was estimated using Bradford assay. Cross reactivity of LLO with SLO was avoided by adsorption of goat sera with SLO as per the method described by Berche et al (1990) with certain modifications. These SLOadsorbed goat sera were then used in the indirect plate ELISA to screen for ALLO as per the method described by Low et al (1992).…”

“…produced by virulencelinked family of genes (Boerlin et al,2003); Act A protein associated with cell-to-cell spread of the agent (Ellin Doyle, 2001), two phospholipases C namely the PI-PLC encoded by plcA gene and the PC-PLC encoded by plcB (Chaudhari et al, 2004a,b); and the autolysin p60 protein (Hess et al, 1996). Out of the mentioned markers, LLO a 58-kDa secreted protein is one of the most important virulence factor produced by L. monocytogenes which can be detected soon after clinical onset of listeriosis and antibodies persist for at least several months (Berche et al, 1990;Shoukat et al, 2013). LLO based ELISA had been used (Low and Donachie, 1991;Low et al, 1992;Boerlin, 2003) however, LLO cross reacts with streptolysin, perfrinolysisn, suilysin and hence need prior adsorption at least with streptolysin O (SLO) before performing LLO-based ELISA (Berche et al, 1990).…”

“…have been developed for screening the animal and human listeriosis cases. However, these conventional assays cannot be relied upon for their poor specificity and sensitivity (Berche et al, 1990). Outer membrane protein (OMP) of Listeria spp.…”

“…Out of the mentioned markers, LLO a 58-kDa secreted protein is one of the most important virulence factor produced by L. monocytogenes which can be detected soon after clinical onset of listeriosis and antibodies persist for at least several months (Berche et al, 1990;Shoukat et al, 2013). LLO based ELISA had been used (Low and Donachie, 1991;Low et al, 1992;Boerlin, 2003) however, LLO cross reacts with streptolysin, perfrinolysisn, suilysin and hence need prior adsorption at least with streptolysin O (SLO) before performing LLO-based ELISA (Berche et al, 1990). Hence, other virulence marker are being searched extensively to remove this pothole and in this regard, Internalin group of protein had proved potential especially InlCbeing an immunodominant and virulence-linked protein, had shown promising result as diagnostic antigen in ELISA for screening the human clinical cases (Grenningloh et al, 1997) and experimental listeric infection in ewes (Zundel et al, 2007), where it proved superior to LLObased ELISA for reliable diagnosis of listeric infection.…”

“…However, these assays fail to discriminate between pathogenic and non-pathogenic Listeria strains. A number of virulence markers of Listeria species capable of eliciting the antibody response during listerial infection such as listeriolysin-O (LLO) (Berche et al,1990); internalins (InlA, InlB, InlC, InlC2, InlJ etc. ), the leucine rich repeat (LRR) proteins of Listeria spp.…”