Abstract: The present invention relates generally to a T cell growth factor. More particularly, the present invention relates to a T cell growth factor which comprises a glycoprotein which supports interleukin 2- and interleukin 4-independent growth of helper T cells. Even more particularly, the present invention relates to the helper T cell growth factor P40, pharmaceutical compositions thereof and antibodies thereto. The present invention also contemplates a method for inducing the proliferation of helper T cells. The helper T cell growth factor contemplated herein is useful in the stimulation of specific cells in the immune system.

Abstract: The invention concerns polypeptides related to human immunoglobulin E binding factors (IgE-Bfs), mRNa, DNAs and hybrid vectors coding for said polypeptides, hosts containing said hydrid vectors, processes for the preparation of said polypepties, mRNAs, DNAs, hybrid vectors, and hosts. The polypeptides can be used for the prevention and/or the treatment of allergic diseases, and accordingly the invention concerns also pharmaceutical preparations containing them.