BACKGROUND: Langerhans cells (LCs) play essential roles in the initiation and regulation of cutaneous immune responses mediated through their successful migration from the epidermis to draining lymph nodes while carrying antigen. Tumour @entity39 factor ( @entity310 , a keratinocyte-derived cytokine, has recently been shown to play an important role in the mobilization of LCs from @entity1 epidermis. Although it is known that with age the immune system changes, the influence of increasing age on the function of @entity1 LCs has not been defined clearly. OBJECTIVES: To examine the influence of age on the ability of @entity310 to induce LC migration. METHODS: Ten elderly (six @entity1 , four @entity1 ; mean age 76 years, range 72-79) and 10 young (six @entity1 , four @entity1 ; mean age 23 years, range 18-35) volunteers received intradermal injections of 200 U of @entity1 recombinant @entity310 diluted in sterile saline, and control injections of sterile saline alone, at each of two paired sites identified on photoprotected buttock skin. Two hours later, paired injection sites were excised by punch biopsy. One set of paired biopsies was processed for assessment of the frequency and morphology of epidermal LCs, following preparation of epidermal sheets and immunofluorescence staining for the LC marker @entity4896 . The remaining paired biopsies were processed in @entity406 and the inflammatory response to @entity310 was assessed by standard histological examination. RESULTS: Mean +/- SEM baseline values for LC frequency within epidermal sheets were significantly different between young (1156.3 +/- @entity19 cells mm(-2)) and elderly subjects (835.7 +/- 48.2 cells mm(-2); P < 0.01). Intradermal injections of 200 U of @entity310 caused a significant reduction in the frequency of LCs in both elderly and young subjects (P < 0.01). However, the extent of @entity310 -induced LC migration was substantially different between the two groups, with a mean 9% reduction in LC frequency in elderly volunteers compared with a mean 23% decrease in young subjects. Exposure to @entity310 was associated with a perivascular polymorphonuclear infiltrate at 2 h in all young subjects; in contrast, only 50% of the elderly individuals showed evidence of such a response. CONCLUSIONS: There are significant differences between young and old skin with respect to both resting LC numbers and their response to @entity310 . These age-related changes in LC frequency and function may contribute to the altered cutaneous immune function observed in the elderly.

Tumour XXXX factor-alpha-induced migration of @entity1 Langerhans cells: the influence of ageing.

@entity1 :: ('9606', 'Species') :: ['women', 'human', 'men'] @entity39 :: ('MESH:D009336', 'Disease') :: ['necrosis'] @entity310 :: ('7124', 'Gene') :: ['TNF)-alpha', 'TNF-alpha'] @entity19 :: ('10090', 'Species') :: ['38.5'] @entity406 :: ('MESH:D005557', 'Chemical') :: ['formalin'] @entity4896 :: ('909', 'Gene') :: ['CD1a']
@entity39 :: (MESH:D009336,Disease) :: ['necrosis']
