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Interleukin-6 promotes human epidermal keratinocyte proliferation and keratin cytoskeleton reorganization in culture

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Abstract

We have studied the effects of interleukin-6 (IL-6) on human epidermal keratinocytes by using serum-free culture conditions that allow the serial transfer, differentiation, and formation of well-organized multilayered epithelia. IL-6 at 2.5 ng/ml or higher concentrations promoted keratinocyte proliferation, with an ED50 of about 15 ng/ml and a maximum effect at 50 ng/ml. IL-6 was 10-fold less potent than epidermal growth factor (EGF) or transforming growth factor-α (TGF-α) and supported keratinocyte growth for up to eight cumulative cell generations. IL-6-treated keratinocytes formed highly stratified colonies with a narrower proliferative/migratory rim than those keratinocytes stimulated with EGF or TGF-α; confluent epithelial sheets treated with IL-6 also underwent an increase in the number of cell layers. We also examined the effect of IL-6 on the keratin cytoskeleton. Immunostaining with anti-K16 monoclonal antibodies showed that the keratin network was aggregated and reorganized around cell nucleus and that this was not attributable to changes in keratin levels. This is the first report concerning the induction of the reorganization of keratin intermediate filaments by IL-6 in human epidermal keratinocytes.

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Acknowledgements

We are grateful to Meytha Marsch-Moreno (IBQ) for preparing the human epidermal keratinocyte banks and the mytomycin-C-treated feeder cells, to Mrs. Erika Sánchez Guzmán and Ms. Ana Ruth Cristóbal-Ramos for technical assistance, to Ms. Maria Elena Rojano for secretarial assistance, and to Mr. Alberto Rodriguez and Mrs. Columba Guadarrama for their technical assistance in the preparation of all materials.

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  1. Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. Postal 14-740, México, 07000, Mexico

    Miriam Hernández-Quintero, Walid Kuri-Harcuch & Federico Castro-Muñozledo

  2. Department of Experimental Pathology, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. Postal 14-740, México, 07000, Mexico

    Arturo González Robles

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  1. Miriam Hernández-Quintero
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  2. Walid Kuri-Harcuch
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  3. Arturo González Robles
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  4. Federico Castro-Muñozledo
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Correspondence to Federico Castro-Muñozledo.

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This work was supported in part by CONACyT grant nos. 1314P-N9507 and G28272-N.

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Hernández-Quintero, M., Kuri-Harcuch, W., González Robles, A. et al. Interleukin-6 promotes human epidermal keratinocyte proliferation and keratin cytoskeleton reorganization in culture. Cell Tissue Res 325, 77–90 (2006). https://doi.org/10.1007/s00441-006-0173-9

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