Myoblast transfer therapy (MTT) is a cell-mediated gene transfer method aim
ed at the restoration of normal dystrophin expression in Duchenne muscular
dystrophy (DMD). Initial clinical MTT trials were conducted amid much contr
oversy, as they were based on very few animal studies. Unfortunately, the t
rials were of little therapeutic benefit. As a result, there has been a ren
aissance of interest in experimental studies in animal models. In MTT, myob
lasts are obtained by muscle biopsy from normal, i.e., dystrophin-positive,
donors, expanded in culture, and injected directly into the muscles of dys
trophic recipients. The major requirement for successful MTT is the surviva
l of injected donor myoblasts in the host environment. However, a vast majo
rity of donor cells fail to survive for more than 1 h after injection, and
very few last beyond the first week. This review on the immunological aspec
ts of MIT focuses in particular on the roles of specific components of the
host immune response, the effects of tissue culture on donor cells, and str
ategies under development to circumvent the problem of donor myoblast death
after injection in vivo.