An unexpected twist in alopecia areata pathogenesis: are NK cells protective and CD49b+ T cells pathogenic?

Natural killer (NK) cells have become a recent focus of interest in alopecia areata (AA) research. To further investigate their role in an established mouse model of AA, lesional skin from older C3H/HeJ mice with AA was grafted to young C3H/HeJ female mice, and NK cells were depleted by continuous administration of rabbit anti-asialo GM1. As expected, this significantly reduced the number of pure NK cells in murine skin, as assessed by NKp46 quantitative immunohistochemistry.

Fas pulls the trigger on psoriasis.

Fas/FasL signaling is best known for induction of apoptosis. However, there is an alternate pathway of Fas signaling that induces inflammatory cytokines, particularly tumor necrosis factor (TNF)-alpha and interleukin (IL)-8. This pathway is prominent in cells that express high levels of anti-apoptotic molecules such as Bcl-xL.

Effect of non-steroidal anti-inflammatory drugs on natural killer cell activity in patients with dementia.

Background: Alteration of innate and acquired immunity can play a role in the mechanism involved in the development of dementia. Epidemiologic studies indicate that the use of non-steroidal anti-inflammatory drugs can delay the onset or slow progression of Alzheimer disease.

Objectives: To determine whether the use of NSAIDs is associated with natural killer activity alteration in AD and multi-infarct vascular dementia patients, as compared with non-demented elderly and healthy young people.

Aging of human epidermis: reversal of aging changes correlates with reversal of keratinocyte fas expression and apoptosis.

The goal of this study was to determine the role of Fas-mediated apoptosis in human epidermal aging. Epidermal Fas expression and apoptosis are increased in aged human skin. Aging changes of human epidermis, including decreased epidermal thickness and proliferation, are reversed following grafting of human skin to SCID (severe combined immunodeficiency) mice.