The major objective of this project is to develop, solicit and make available monoclonal antibodies of hybridomas relevant to limb development. The goal of the Developmental Studies Hybridoma Bank (DSHB) has been to build an easily accessible source of well-characterized products at reasonable cost through solicitation of existing hybridomas and through the development of new hybaridomas. The continuation to the project will expand the DSHB into other areas of development, including the human immune system.