0000000000451338
AUTHOR
R Van Brandwijk
Increased Level of Phosphotyrosine in Human Dendritic Cells under Stimulation with Contact Sensitizers but Not Irritants
In the last years evidence was presented for the activation of dendritic cells (DC) under stimulation with contact sensitizers. Most data were obtained for murine Langerhans cells (LC) whereas in man blood-derived dendritic cells were found to be a more suitable model to study the mechanism of DC activation by haptens. The first observation was the upregulation of MHC class II molecules on murine Langerhans cells in vivo1 followed by their migration from the epidermis into regional lymph nodes2. Very early events during this activation include the upregulation of IL-1s in murine LC3 as well as the endocytotic activation of this cell type4. Based on the last observation attempts were made to…
Tcgfiii/p40 is produced by naive murine cd4+ t cells but is not a general t cell growth factor*
Several antigen-specific T cell lines were found to secrete a lymphokine upon activation by antigen or lectin that was provisionally termed T cell growth factor III (TCGF III) because it induced the proliferation of a CD4+ T cell clone independently from IL2 and IL4. Amino acid sequence analysis (and the functional properties of TCGF III) revealed that TCGF III was identical with a recently identified lymphokine termed P40. TCGF III/P40 was not only produced by long-term cultured T cell lines but also upon stimulation of freshly isolated Mlsa-reactive T cells. In addition, naive CD4+ T cells secreted TCGF III/P40 upon activation by lectin or allo-major histocompatibility complex structures.…