z-logo
Premium
Evidence for modulation of human epidermal differentiation and remodelling by CD40
Author(s) -
Concha M.,
Vidal M.A.,
Moreno I.,
Salem C.,
Figueroa C.D.,
Schmitt D.,
PÉguetNavarro J.
Publication year - 2003
Publication title -
british journal of dermatology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.304
H-Index - 179
eISSN - 1365-2133
pISSN - 0007-0963
DOI - 10.1046/j.1365-2133.2003.05300.x
Subject(s) - cd40 , epidermis (zoology) , keratinocyte , filaggrin , biology , cellular differentiation , immunocytochemistry , population , microbiology and biotechnology , immunology , cell culture , endocrinology , medicine , in vitro , anatomy , cytotoxic t cell , biochemistry , genetics , atopic dermatitis , environmental health , gene
Summary Background  It is widely accepted that CD40 plays a critical role in the regulation of immune response. However, the significance of CD40 expression on normal human keratinocytes is only partially known. Objectives  To perform a morphological re‐examination of the role of CD40 on the differentiation of human keratinocytes and remodelling of the epidermis. Methods  Keratinocytes were grown on fibroblasts transfected with the CD40 ligand (CD40L) to investigate the formation of epidermal sheets in culture under the influence of the CD40L. Control experiments were carried out using the same cells but transfected with CD32. Further, three specific anti‐CD40 monoclonal antibodies were used as soluble agonists to analyse the effect of CD40 ligation on keratinocyte differentiation. Results  Epidermal sheets developing from keratinocytes cocultured with fibroblasts transfected with CD40L but not with CD32 showed an up to 50% reduction in thickness compared with control sheets. This change depended mostly on cellular flattening and a decrease in the number of cell layers, and was coincident with a transient decrease in cell surface CD40 immunoreactivity. On the other hand, normal epidermis, and freshly isolated and cultured keratinocytes revealed a predominant CD40+/Ki‐67– phenotype that was demonstrated by double immunocytochemistry. Consistent with these observations, keratinocytes primed with interferon‐γ responded to the three soluble agonists, but not to control IgG1, producing immunoreactive (pro)filaggrin and displaying morphological changes in shape and size equivalent to those seen in differentiated cells. Conclusions  As a whole, our findings provide evidence that CD40+ keratinocytes represent a poorly differentiated population, not actively engaged in the cell cycle, which under specific stimulation is committed towards terminal differentiation.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here