In general, disclosed are methods of inhibiting autoreactive immune cell proliferation in a mammal, involving administering to themammal a therapeutically effective amount of recombinant human alpha-fetoprotein or an immune cell anti-proliferative fragment or analogthereof； methods of inhibiting a neoplasm in a mammal, involving administering to the mammal a therapeutically effective amount ofrecombinant human alpha-fetoprotein or an anti-neoplasm fragment or analog thereof； and methods of cell culture, involving the use of amedia containing human alpha-fetoprotein or a fragment or analog thereof.
