High expression of integrin beta1 correlates with high proliferation capacity in oral keratinocytes.
OBJECTIVE
Large defects of the oral mucosa are still a major challenge in reconstructive surgery. For the development of oral mucosal grafts, successful enrichment of cells with a high proliferative potential is highly desirable. Therefore, the aim of this study was to separate two fractions of oral keratinocytes based on their affinity to collagen type IV.


METHODS
Oral keratinocytes were isolated from oral mucosa and separated into two fractions with different affinities to collagen type IV. Growth curves, Western blot analysis and immunohistochemical staining were used to detect differences between the two cell fractions.


RESULTS
The cell fraction (RAC-IV) that adhered to collagen type IV within 20 min showed higher proliferative potential, significantly higher (P < 0.05) expression of integrin beta1 and fewer apoptotic cells. In particular, this fraction included small proliferating cells with the typical polygonal shape of oral keratinocytes, whereas the non-proliferating cells (RAC-IV-D) were irregularly shaped. Immunohistochemical staining showed only some apoptotic RAC-IV cells, whereas RAC-IV-D cells showed a significant increase of M30-positive cells. In addition, Western blotting revealed significantly higher (P < 0.05) expression of integrin beta1 in the RAC-IV fraction than in the RAC-IV-D fraction.


CONCLUSIONS
Our results show that it is possible to enrich a fraction of highly proliferative oral keratinocytes by means of their high affinity to collagen type IV.
Stein
Elisabeth
E
Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria.
Blaimauer
Karin
K
Bauer
Sieglinde
S
Erovic
Boban M
BM
Turhani
Dritan
D
Thurnher
Dietmar
D
D000293:Adolescent; D000328:Adult; D000368:Aged; D015153:Blotting, Western; D002452:Cell Count; D002458:Cell Fractionation; D049109:Cell Proliferation; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D024141:Collagen Type IV / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D019012:Integrin beta1 / Q000032:analysis*; D015603:Keratinocytes / Q000166:cytology* / Q000378:metabolism; D008875:Middle Aged; D009061:Mouth Mucosa / Q000166:cytology* / Q000637:transplantation; D013194:Staining and Labeling; D013997:Time Factors; D023822:Tissue Engineering
D024141:Collagen Type IV; D019012:Integrin beta1