Transport of amino-acids across renal brush border membrane vesicles in Mycobacterium leprae infected Swiss albino mice--effect of Convit vaccine.

Brush border membrane vesicles prepared from kidneys of Mycobacterium leprae infected (non-vaccinated) and vaccinated-infected Swiss albino mice were used to assess the effect of Convit's combined vaccine (BCG + M. leprae) on amino acid transport activity across the tubular basement membrane. The protective effect of Convit's vaccine was more pronounced with respect to the uptake of L-alanine than L-aspartate. Uptake of L-lysine showed no significant difference in the different groups. Footpad counts followed characteristic growth curves in the non-vaccinated infected group but showed a lag in the development of peak levels in the vaccinated group. Further Convit's vaccine appeared to have a protective effect on renal impairment in the mouse model of leprosy in the initial stages of infection only, as indicated by the transient reversal of amino acid uptake and a diminution in the footpad counts induced by M. leprae infection. No significant (P > 0.05) protective effect of the vaccine was found in the advanced disease state.

Renal brushborder membrane vesicle. Study of marker enzymes and uptake of nutrients in Mycobacterium leprae infected mice.

The renal brush border membrane vesicles (BBMV) were used to elucidate the early biochemical functional status during the course of experimental M. leprae infection in mice. The activities of the characteristic brush-border enzymes viz: alkaline phosphatase, leucine amino peptidase and gamma-glutamyl transpeptidase were found to be significantly decreased (p less than 0.001) at 3 and 6 months after infection. The transport of nutrients viz: D-glucose, L-alanine, L-lysine and L-aspartate across BBMV showed similar pattern. The activity of brush border enzymes and transport of nutrients across the membrane returned to normal at 9 months post-infection suggesting regeneration of the brush border membrane.