UNASSIGNED: Five billion normal myoblasts were injected into each of 21 @entity1555 ( @entity1555 ) @entity1 aged 6-14 yr to assess the feasibility, safety, and efficacy of the Phase II myoblast transfer therapy (MTT). The Phase II study was designed to strengthen muscles of both lower limbs. Forty-eight intramuscular injections transferred the myoblasts into 22 major muscles at 55.6 * 106/mL in 10 min under general anesthesia. Eleven @entity1 had received 8 million myoblasts each 1 yr ago in the Phase I MTT. In the Phase II study, eight of them had their myoblasts subcultured from reserves frozen 1 yr ago. The donor myoblasts for each of the remaining @entity1 were cultured from satellite cells derived from a 1-g muscle biopsy of a normal male who might or might not be histocompatible with the recipient. The immunosuppressant @entity205 ( @entity49844 ) is being administered to recipients for 6 mo after MTT to facilitate donor cell survival. There was no evidence of an adverse reaction to MTT or @entity49844 as determined by serial laboratory evaluations including electrolytes, @entity1011 , and @entity1133 . Early objective functional tests using the KinCom Robotic Dynamometer were conducted on 13 subjects aged 6 to 13 before MTT and at 3 mo after MTT. Of the 69 muscle groups (knee extensors, knee flexors, plantar flexors) tested for isometric force generation in these subjects, 43% showed mean increase of 41.3%    5.9 SEM, 38% showed no change, and 19% showed continuous force reduction of 23.4%    3.1 SEM. The remaining subjects await the 3-mo post-MTT evaluation. The results indicate that 1) MTT is safe; 2) MTT increases muscle strength in @entity1555 : 81% of the muscles tested showed either increase in strength or did not show continuous loss of strength; 3) more than 5 billion myoblasts can be cultured from 1 g normal muscle biopsy, providing unprecedented numbers of cells for MTT; 4) myoblasts, frozen over I yr, retain the ability to proliferate from 10 million to 5 billion, and to form normal myofibers; 5) injections of 5 billion myoblasts have not provoked any immunological rejection symptoms in the Phase II subjects, 11 of whom received 8 million myoblasts in the Phase I MTT a year ago; 6) it is safe to perform multiple injections of myoblasts into lower limb muscles without formation of emboli; and 7) donor cell rejection by the recipient can be prevented with @entity49844 when properly managed.

FEASIBILITY, SAFETY, AND EFFICACY OF MYOBLAST TRANSFER THERAPY ON DUCHENNE MUSCULAR DYSTROPHY XXXX .

@entity1 :: ('9606', 'Species') :: ['boys'] @entity49844 :: ('D003520', 'Chemical') :: ['Cy'] @entity1133 :: ('MESH:D014508', 'Chemical') :: ['urea'] @entity1555 :: ('MESH:D020388', 'Disease') :: ['Duchenne muscular dystrophy', 'DMD'] @entity205 :: ('MESH:D016572', 'Chemical') :: ['cyclosporine'] @entity1011 :: ('MESH:D003404', 'Chemical') :: ['creatinine']
@entity1 :: (9606,Species) :: ['BOYS']
