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 especially from murine and human sources and further which is capable of augmenting proliferation of IL3- or IL4-responsive cells. Even more particularly, the present invention relates to the helper T cell growth factor P40, pharmaceutical compositions thereof, antibodies thereto and recombinant DNA clones thereof. The present invention also contemplates a method for inducing the proliferation of helper T cells as well as IL3- and Il4-responsive cells. The helper T cells growth factor contemplated herein is useful in the stimulation of specific cells in the immune system, either alone or in combination with IL3 or IL4.

Abstract: A method for inhibiting production of IgE, and a method for enhancing production of IgG are taught. The methods are linked to the role of interleukin 9 in antibody production. Specifically, production of IgG is potentiated by administering either to a subject or a cell culture a combination of interleukin 4 and interleukin 9. Production of IgE is inhibited by administering an amount of an interleukin 9 inhibitor to a subject.

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 relates to substantially pure interleukin 9 receptor molecules and the use thereof. The uses include use as an interleukin-9 inhibitor, as a diagnostic agent for determining interleukin-9, and as a screening agent for pharmaceuticals. The interleukin-9 receptor is characterized as a glycoprotein of about 64 kilodaltons which, upon digestion with N-glycosidase F, yields a peptide of about 54 kilodaltons.

Abstract: The glycoprotein known as P40, characterized by a molecular weight of from about 30 to 40 kilodaltons and an isoelectric point of about 10, previously recognized as a helper T cell growth factor, also enhances growth and proliferation of mast cells and their maintenance viability and differentation status in vitro.

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 especially from murine and human sources and further which is capable of augmenting proliferation of IL3- or IL4-responsive cells. Even more particularly, the present inventin relates to the helper T cell growth factor P40, pharmaceutical compositions thereof, antibodies thereto and recombinant DNA clones thereof. The present invention also contemplates a method for inducing the proliferation of helper T cells as well as IL3- and Il4-responsive cells. The helper T cells growth factor contemplated herein is useful in the stimulation of specific cells in the immune system, either alone or in combination with IL3 or IL4.

Abstract: A method for inhibiting production of IgE, and a method for enhancing production of IgG are taught. The methods are linked to the role of interleukin 9 in antibody production. Specifically, production of IgG is potentiated by administering either to a subject or a cell culture a combination of interleukin 4 and interleukin 9. Production of IgE is inhibited by administering an amount of an interleukin 9 inhibitor to a subject.

Abstract: The invention relates to substantially pure interleukin 9 receptor molecules and the use thereof. The uses include use as an interleukin-9 inhibitor, as a diagnostic agent for determining interleukin-9, and as a screening agent for pharmaceuticals. The interleukin-9 receptor is characterized as a glycoprotein of about 94 kilodaltons which, upon digestion with N-glycosidase F, yields a peptide of about 54 kilodaltons.