Electron‐microscopic Observation of a Human Epidermal Langerhans Cell in Mitosis

Kanitakis, Jean; Hoyo, E; Perrin, C; Schmitt, Daniel

doi:10.1111/j.1346-8138.1993.tb03826.x

Cited by 8 publications

(3 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[35-38] Differentiated cells localize to the midepidermis, demonstrate characteristic Birbeck granules, and exhibit dendritic appendages. These differentiated cells, although usually stable, sometime exhibit proliferative activity and increase in many cutaneous immune response states [23,39,40]. The inability of PTU to reduce CD1a expression in biopsy samples of patients with psoriasis suggests that the mechanism of action of this drug is psoriasis is not due to any effect on skin antigen-presenting cells or production of IL-12, a motive cytokine that is responsible for initiation and maintenance of the cytokine stimulatory cascade that leads to formation of the psoriatic plaque [16].…”

Section: Discussionmentioning

confidence: 99%

CD1a expression in psoriatic skin following treatment with propylthiouracil, an antithyroid thioureylene

2003

View full text Add to dashboard Cite

BackgroundThe antithyroid thioureylenes, propylthiouracil (PTU) and methimazole (MMI), are effective in the treatment of patients with plaque psoriasis. The mechanism of action of the drugs in psoriasis is unknown. Since the drugs reduce circulating IL-12 levels in patients with Graves' hyperthyroidism, the effect of propylthiouracil on CD1a expression in psoriatic lesions was examined in biopsy samples of patients with plaque psoriasis. CD1a is a marker of differentiated skin antigen presenting cells (APC, Langerhans cells). Langerhans cells and skin monocyte/macrophages are the source of IL-12, a key cytokine involved in the events that lead to formation of the psoriatic plaque.MethodsBiopsy specimens were obtained from six patients with plaque psoriasis who were treated with 300 mg propylthiouracil (PTU) daily for three months. Clinical response to PTU as assessed by PASI scores, histological changes after treatment, and CD1a expression in lesional skin before and after treatment were studied.ResultsDespite significant improvement in clinical and histological parameters the expression of CD1a staining cells in the epidermis did not decline with propylthiouracil treatment.ConclusionsIt appears that the beneficial effect of propylthiouracil in psoriasis is mediated by mechanisms other than by depletion of skin antigen-presenting cells.

show abstract

Section: Discussionmentioning

confidence: 99%

CD1a expression in psoriatic skin following treatment with propylthiouracil, an antithyroid thioureylene

2003

View full text Add to dashboard Cite

show abstract

“…Experiments based on in situ 3 H‐thymidine and BrdU incorporation showed that 2–3% of epidermal LC are cycling (5) and that murine epidermal LC express the Ki67 proliferation‐associated antigen (6). Several electron microscopic observations of LC undergoing mitosis within human epidermis have also been reported (7). Experimental data obtained in mice have suggested that under steady‐state conditions the efflux of LC to local lymph nodes would be balanced by LC divisions within the epidermis, whereas under conditions severely depleting epidermal LC (such as UV‐radiation), LC precursors would be recruited from the peripheral blood (8).…”

Section: Introductionmentioning

confidence: 93%

Self‐renewal capacity of human epidermal Langerhans cells: observations made on a composite tissue allograft

Kanitakis

Morélon

Petruzzo

et al. 2010

Experimental Dermatology

Self Cite

View full text Add to dashboard Cite

: Epidermal Langerhans cells (LC) are dendritic, antigen‐presenting cells residing within mammalian epidermis and mucosal epithelia. When massively depleted, they are replaced by cells of bone‐marrow origin. However, their renewal within normal skin under steady‐state conditions is not precisely known. We observed that epidermal LC within a human hand allograft remain stable in the long term (10 years) and are not replaced by cells of recipient’s origin; furthermore, we observed a Langerhans cell in mitosis within the epidermis 8 years postgraft. These results show that under almost physiological conditions, human LC renew in the epidermis by local mitoses of preexisting cells.

show abstract

“…Although relatively stable in normal skin, Langerhans cells have been observed to show evidence of replicative activity 15–19 . Upon antigenic stimulation, Langerhans cells rapidly migrate from the epidermal layer into dermal lymphatics and ultimately to draining lymph nodes, where antigen presentation to large numbers of naive T cells can be most efficiently accomplished.…”

Section: Langerhans Cell: Life Historymentioning

confidence: 99%

Langerhans cell microgranulomas (pseudo‐pautrier abscesses): morphologic diversity, diagnostic implications and pathogenetic mechanisms

Burkert¹,

Huhn²,

Menezes³

et al. 2002

J Cutan Pathol

View full text Add to dashboard Cite

The term ‘Langerhans cell microgranuloma’ (LCM) was introduced a decade ago to draw attention to focal collections of these cells within the epidermal layer that develops during certain immune reactions. In spite of a growing awareness of this phenomenon during the past decade, few reports have focused on the development and phenotype of LCM. In this commentary, we review the historical development of the concept of LCM, demonstrate the salient immunomorphologic characteristics of LCM, and advance a hypothesis to explain their sequential evolution and formation.

show abstract

Electron‐microscopic Observation of a Human Epidermal Langerhans Cell in Mitosis

Cited by 8 publications

References 18 publications

CD1a expression in psoriatic skin following treatment with propylthiouracil, an antithyroid thioureylene

CD1a expression in psoriatic skin following treatment with propylthiouracil, an antithyroid thioureylene

Self‐renewal capacity of human epidermal Langerhans cells: observations made on a composite tissue allograft

Langerhans cell microgranulomas (pseudo‐pautrier abscesses): morphologic diversity, diagnostic implications and pathogenetic mechanisms

Contact Info

Product

Resources

About