The production of M. leprae requires
growth in vivo in suitable animal models, as successful in
vitro culture of this microbe has, thus far, not been shown
to be feasible. M. leprae is injected intravenously into
armadillos (performed at the G.W. Long Hansen's Disease Center,
Louisiana State University, Baton Rouge, LA, under the direction
of Dr. Richard Truman), in which the bacteria grow to between
109 to 1011 bacilli per gram of tissue.
The organs from which the bacteria are harvested (liver and
spleen) are sent to CSU where they are processed to obtain purified
M. leprae. The tissue is disrupted by homogenization followed
by chemical and enzymatic digestion to release the bacteria.
The bacilli are then separated from the tissue by phase separation
using a mixture of dextran sulfate and polyethylene glycol.
Purified M. leprae is suspended in phosphate buffered
water containing 0.01% Tween 80 and is quantitated by spectrophotometry.
Contaminating pigment and tissue are graded visually and microscopically,
respectively. Storage is at -70oC.
