Prophylactic evaluation of recombinant extracellular superoxide dismutase of Brugia malayi in jird model.
The immunoscreening of Brugia malayi adult cDNA library with pooled endemic normal sera identified several seroreactive clones including, EC-SOD which contained a 612 bp insert and showed significant nucleotide and deduced amino acid sequence homologies with superoxide dismutase (SOD) of other nematode parasites. The SODs are known to play an important role in the protection of parasite against reactive oxygen species of the host. The coding region of the B. malayi EC-SOD (BmEC-SOD) was cloned and expressed in Escherichia coli followed by affinity purification on nickel agarose resin. Staining of native polyacrylamide gel for SOD activity of the expressed recombinant protein revealed that SOD activity inactivated by potassium cyanide and hydrogen peroxide but not by sodium azide, indicating presence of Cu/Zn-SOD. The rBm EC-SOD protein showed its activity over a broad range of pH.7.0-11.0. Further the immune protective activity of recombinant EC-SOD antigen was evaluated in susceptible host, jirds (gerbils) (Meriones unguiculatus) against B. malayi filarial infection. The immunized jirds showed 33.5% and 36% cytotoxicity against microfilariae and 42.8% and 45.5% cytotoxicity against infective larvae in in vitro antibody dependent cellular cytotoxicity (ADCC) assay and in in situ micropore chamber methods respectively. This study suggests that the rBm EC-SOD antigen could stimulate a partial protective immune response against microfilariae and infective larvae in experimental animals against filarial infection.
Department of Biochemistry & J.B. Tropical Disease Research Center, Mahatma Gandhi Institute of Medical Sciences, Sevagram 442102, MS, India. snehal_214@rediffmail.com
Snehal
S
Dabir
Pankaj
P
Dabir
Kalyan
K
Goswami
Kalyan
K
Goswamy
M V R
MV
Reddy
D000595:Amino Acid Sequence; D000818:Animals; D000909:Antibodies, Helminth / Q000276:immunology*; D017178:Brugia malayi / Q000276:immunology*; D003001:Cloning, Molecular; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D005849:Gerbillinae; D015801:Helminth Proteins / Q000276:immunology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000276:immunology; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013482:Superoxide Dismutase / Q000276:immunology* / Q000378:metabolism; D016019:Survival Analysis
D000909:Antibodies, Helminth; D018509:DNA, Helminth; D004791:Enzyme Inhibitors; D015801:Helminth Proteins; D011994:Recombinant Proteins; D013482:Superoxide Dismutase