Application of monoclonal antibodies generated against Panton-Valentine Leukocidin (PVL-S) toxin for specific identification of community acquired methicillin resistance Staphylococcus aureus

Publication date: December 2014 Source:Microbiological Research, Volume 169, Issue 12 Author(s): Niveditha Sundar Poojary , Shylaja Ramlal , Radhika Madan Urs , Murali Harishchandra Sripathy , Harsh Vardhan Batra Panton-Valentine Leukocidin (PVL) produced by community acquired methicillin Staphylococcus aureus (CA-MRSA) involved in skin and soft-tissue infections and necrotizing pneumonia comprised of two fractions, namely PVL S and PVL F. In the present study, three monoclonal antibodies designated as MAb1, MAb9 and MAb10 were generated against recombinant PVL-S (35kDa) protein of S. aureus. All the three MAbs specifically reacted to confirm PVL-S positive strains of S. aureus recovered from clinical samples in Western blot analysis. Similarly all the three MAbs did not show any binding to other tested 14 different pathogenic bacteria belonging to other genera and species in Western blot analysis. Furthermore, a simple dot-ELISA method was standardized for the identification of PVL-S toxin containing S. aureus strains. Initially in dot-ELISA, Protein A (Spa) of S. aureus posed background noise problems due to the non-specific binding of antibodies resulting in false positive reactions. With the addition of 10mM diethylpyrocarbonate (DEPC) along with 5% milk in PBS in the blocking step prevented this non-specific binding of Spa to mouse anti-PVL monoclonal antibodies in dot-ELISA. Once standardized, this simple dot-ELISA was evaluated with nine PVL positive strains r...
Source: Microbiological Research - Category: Infectious Diseases Source Type: research