Comparison in Expression of CD 1 , HLA - DR and ICAM - 1 of Follicular Keratinocytes from a Lesion and a Non - Lesional Scalp of Alopecia Areata

Lee, Won Soo; Ahn, Sung Ku; Lee, Seung Hun

Abstract

BACKGROUND: Primary targit injured from the immunologic mechanism of alopecia areata is not definitely confirmed although alopecia areata is regarded as a disease occuring from certain im munologic process. Recently, par ticular interest has been focused on the follicular keratinocytes which show morphologic and anigenic alterations in active lesions. Another important point is the subclinical state hypothesi. It is based upon the observation that the patterns of T lymphocytes infiltration and ultrastructural changes of dermal papilla cells are nearly identical in active lesions and in non-lesional areas of alopecia areata.
OBJECTIVE
The purpose of this study is to determine and to compare the aberrant expression of HLA-DR, CD1 and ICAM-1 on the follicular keratinocytes from the active alopecia areata lesion, stationary lesion and non-lesional scalp.
METHODS
We performed a n immunohistochemical study, using the streptavidin system to compare the patterns of HLA-DR, CD1 and ICAM-1 immunoreactivity in the follicular keratinocytes in five active alopecia lesions two stationary lesions and non-lesional scalp specimens among four active and two stationary patients, and two normal control scalp specimens.
RESULTS
In the active aloecia lesions, the HLA-DR and ICAM-1 immunoreactivity was observed in some patients while CD1 immunoreactivity was observed in all the patients. In the sta tionary alopecia lesions, none of the HLA-DR or CD1 or ICAM-1 immunoreactivity was observed as was the case in the norrial control scalp specimens. In the non-lesional normal scalp specimens, the HLA-DR, CD1 and ICAM-1 immunoreactivity showed nearly the same patterns as those in the acute alopecia leions.
CONCLUSION
The aberrant antigenic alterations, especially CD1 expression of follicular keratinocytes are likely to be asociated with the active progress of alopecia areata lesions. These antigenic alterations were also observed in non-lesional scalp as well as alopecia areata lesions in the very similar patterns.