The media of the normal bovine main pulmonary artery (MPA) is composed of phenotypically heterogeneous smooth muscle cells (SMC) with markedly different proliferative capabilities in response to serum, mitogens, and hypoxia. Little, however, is known of the SMC phenotype in distal pulmonary arteries (PA), particularly in arterioles, which regulate the pulmonary circulation. With a panel of musc...

Of 52 cancer patients studied for their in vitro response in lymphocyte blastogenesis assays, 50 were also studied for immunocompetence by in vivo assays. The in vivo assays used were the delayed cutaneous hypersensitivity reaction to the primary stimulus of 2,4-dinitrochlorobenzene (DNCB), and the recall reactions to four common microbial antigens. The in vitro assays were the blastogenic resp...

ERK1 and ERK2 mitogen-activated protein kinases (MAPK) play a critical role in regulation of cell proliferation and differentiation in response to mitogens and other extracellular stimuli. Mitogens and cytokines that activate MAPK in T cells have been shown to activate human immunodeficiency virus type 1 (HIV-1) replication. Little is known about the signal transduction pathways that activate H...

Lymphocytes were highly purified from synovial fluid and peripheral blood of 10 rheumatoid arthritis patients and assessed for responsiveness to PHA-P and Con-A. In all cases, both synovial and blood lymphocytes showed a marked reduction in response to these mitogens compared with normal blood lymphocytes. The factors responsible for this low T cell responsiveness are discussed.

Cultures of bovine peripheral blood leukocytes were prepared from calves inoculated with Mycobacterium bovis and with M. avium. Suitable lymphocyte stimulation was obtained with specific and nonspecific mycobacterial mitogens. Leukocyte cultures depleted of adherent, macrophage-type cells did not respond to stimulation with purified protein derivative, although they were responsive to phytohema...

The proliferation and motility of vascular endothelial cells (ECs) are critical steps in angiogenesis and are strictly controlled by different extracellular signals. Among mitogens, peptides binding to tyrosine kinase receptors (i.e. VEGFs and FGFs) are well known and are released by several cell types, including ECs and tumor cells. The binding of mitogens to their specific receptors triggers ...