Laziness

why are we so lazy? Keratinization, absence of granular layer, and depositation of antibodies and complement components in the stratum corneum. Most notable is the hyperproliferation of keratinocytes in the epidermis. These keratinocytes exhibit an increased mitotic rate and have ten times the turnover rate of normal keratinocytes. There is also an infiltration of CD4+ T lymphocytes, monocytes and neutrophils into the epidermis. Recently there has been much debate over whether psoriasis is mediated by …

…is causing an autoimmune reaction. This antigen may be only expressed during adolescence, hence the onset of disease during this time. It could be that these sufferers have lost tolerance to this self antigen and have initiated an autoimmune response to the new challenge. There may be other genetic defects which can lead to the psoriatic phenotype, but these are probably distinct from Type I psoriasis, which I believe to be a true autoimmune disease.