TY - JOUR
T1 - Impaired hair follicle morphogenesis and cycling with abnormal epidermal differentiation in nackt mice, a cathepsin L-deficient mutation
AU - Benavides, Fernando
AU - Starost, Matthew F.
AU - Flores, Mónica
AU - Gimenez-Conti, Irma B.
AU - Guénet, Jean Louis
AU - Conti, Claudio J.
N1 - Funding Information:
Supported by grant CA69146 from the National Institutes of Health (to C. J. C.).
PY - 2002
Y1 - 2002
N2 - We previously described an autosomal-recessive mutation named nackt (nkt) exhibiting partial alopecia associated with CD4+ T-cell deficiency. Also, we recently reported that nkt (now Ctslnkr) comprises a deletion in the cathepsin L (Ctsl) gene. Another recent study reported that Ctsl knockout mice have CD4+ T-cell deficiency and periodic shedding of hair, which recapitulate the nkt mutation and the oldfurless (fs) mutation. The current study focuses on the dermatological aspects of the nkt mutation. Careful histological analysis of skin development of homozygous nkt mice revealed a delayed hair follicle morphogenesis and late onset of the first catagen stage. The skin of Ctslnkt/Ctslnkt mice showed mild epidermal hyperplasia and hyperkeratosis, severe hyperplasia of the sebaceous glands, and structural alterations of hair follicles. Epidermal differentiation seems to be affected in nkt skin, with overexpression of involucrin and profilaggrin/filaggrin along with focal areas of keratin 6 expression in the interfollicular epidermis. Severe epidermal hyperplasia, acanthosis, orthokeratosis, and hyperkeratosis were only observed in mice maintained in nonpathogen-free environments. The analysis of Rag2-/- Ctslnkt/Ctslnkt double-mutant mice indicates that the skin defect remains under the absence of T and B cells. This animal model provides in vivo evidence that cysteine protease cathepsin L plays a critical role in hair follicle morphogenesis and cycling, as well as epidermal differentiation.
AB - We previously described an autosomal-recessive mutation named nackt (nkt) exhibiting partial alopecia associated with CD4+ T-cell deficiency. Also, we recently reported that nkt (now Ctslnkr) comprises a deletion in the cathepsin L (Ctsl) gene. Another recent study reported that Ctsl knockout mice have CD4+ T-cell deficiency and periodic shedding of hair, which recapitulate the nkt mutation and the oldfurless (fs) mutation. The current study focuses on the dermatological aspects of the nkt mutation. Careful histological analysis of skin development of homozygous nkt mice revealed a delayed hair follicle morphogenesis and late onset of the first catagen stage. The skin of Ctslnkt/Ctslnkt mice showed mild epidermal hyperplasia and hyperkeratosis, severe hyperplasia of the sebaceous glands, and structural alterations of hair follicles. Epidermal differentiation seems to be affected in nkt skin, with overexpression of involucrin and profilaggrin/filaggrin along with focal areas of keratin 6 expression in the interfollicular epidermis. Severe epidermal hyperplasia, acanthosis, orthokeratosis, and hyperkeratosis were only observed in mice maintained in nonpathogen-free environments. The analysis of Rag2-/- Ctslnkt/Ctslnkt double-mutant mice indicates that the skin defect remains under the absence of T and B cells. This animal model provides in vivo evidence that cysteine protease cathepsin L plays a critical role in hair follicle morphogenesis and cycling, as well as epidermal differentiation.
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U2 - 10.1016/S0002-9440(10)64225-3
DO - 10.1016/S0002-9440(10)64225-3
M3 - Article
C2 - 12163394
AN - SCOPUS:0036968842
SN - 0002-9440
VL - 161
SP - 693
EP - 703
JO - American Journal of Pathology
JF - American Journal of Pathology
IS - 2
ER -