Can this be helped?

My brother Michael is 16 and I'm really afraid for him. He's always been
kind of a loner, neveer really making any friends and always kinda
doing his own thing. He's a nice kid and funny but we've attended so many
schools it's been hard for both of us to make good friends. He's also
always enjoyed TV and electronics.
But recently it's gotten much worse. i'm at college now so i'm not here as
often. he's probably gained 20 lbs since i've left. he just sits in his
chair in the TV room watching TV and just fiddling around on his laptop.
he's also really only interested in kids shows like pokemon and power
rangers.
he does a couple of things at school but not very much. we were thinking
about getting him more involved but i don't know if that'll work. he's
just so immature. i just don't know what to do- can anyone help?