M D Alcántar-Curiel1, E García-Latorre, J I Santos. 1. Laboratorio de Bacteriología Intestinal, Hospital Infantil de México Federico Gómez, Secretaría de Salud (SSa), México, D.F., Mexico.
Abstract
BACKGROUND: Klebsiella pneumoniae is a major cause of neonatal sepsis and nosocomial infections in Mexico. Antibiotic therapy is the first choice for treatment but the increase in multiple resistance strains has forced scientists to look for alternative treatments, such as immunotherapy. In this work, we propose that porins could be a common antigen among four different capsular serotypes of Klebsiella pneumoniae for the production of immune sera with opsonizing capacity. METHODS: The 35 and 36 kDa porins from four different serotypes of the bacteria were isolated by the Nikaido method followed by purification in Sephacryl column chromatography. The 36 kDa of serotype K8 was further purified by electroelution. The 35 and 36 kDa porins were used to obtain rabbit polyclonal antibodies (PolyAb) to the four serotypes and the 36 kDa from K8 for the production of monoclonal antibodies (MoAb). Antigenic reactivity of PolyAb and MoAb were analyzed by ELISA and WB and their opsonizing capacity for human PMN was measured by chemiluminescence (CL) using capsulated and non-capsulated bacteria. RESULTS: Porins from the four strains showe electrophoretic homology and cross reaction by ELISA and WB. CL assays indicated that PolyAb opsonized heterologous strains and that MoAb perform this in the absence of capsule. CONCLUSIONS: K.pneumoniae 35 and 36 kDa porins are common antigens for the four serotypes studied and induce opsonizing antibodies.
BACKGROUND:Klebsiella pneumoniae is a major cause of neonatal sepsis and nosocomial infections in Mexico. Antibiotic therapy is the first choice for treatment but the increase in multiple resistance strains has forced scientists to look for alternative treatments, such as immunotherapy. In this work, we propose that porins could be a common antigen among four different capsular serotypes of Klebsiella pneumoniae for the production of immune sera with opsonizing capacity. METHODS: The 35 and 36 kDa porins from four different serotypes of the bacteria were isolated by the Nikaido method followed by purification in Sephacryl column chromatography. The 36 kDa of serotype K8 was further purified by electroelution. The 35 and 36 kDa porins were used to obtain rabbit polyclonal antibodies (PolyAb) to the four serotypes and the 36 kDa from K8 for the production of monoclonal antibodies (MoAb). Antigenic reactivity of PolyAb and MoAb were analyzed by ELISA and WB and their opsonizing capacity for human PMN was measured by chemiluminescence (CL) using capsulated and non-capsulated bacteria. RESULTS: Porins from the four strains showe electrophoretic homology and cross reaction by ELISA and WB. CL assays indicated that PolyAb opsonized heterologous strains and that MoAb perform this in the absence of capsule. CONCLUSIONS:K.pneumoniae 35 and 36 kDa porins are common antigens for the four serotypes studied and induce opsonizing antibodies.
Authors: Chee Sian Kuan; Mun Teng Wong; Sy Bing Choi; Ching Ching Chang; Yoke Hiang Yee; Habibah A Wahab; Yahaya Mohd Normi; Wei Cun See Too; Ling Ling Few Journal: Int J Mol Sci Date: 2011-07-07 Impact factor: 5.923