1. Keratin 15 Expression in Stratified Epithelia: Downregulation in Activated Keratinocytes 
Ahmad Waseem, Yasmin Alam, Anand Lalli 
Journal of Investigative Dermatology 
Volume 112, Issue 3, Pages (March 1999)
DOI: /j x
Copyright © 1999 The Society for Investigative Dermatology, Inc Terms and Conditions

2. Figure 1
LHK15 reacts specifically with K15 polypeptide on immunoblots. (a) Detection of K15 in cytoskelet al extract of different human epithelial cells. Keratin polypeptides were extracted from cultured keratinocytes using low and high salt buffers containing Triton X-100, separated on a 12% sodium dodecyl sulfate polyacrylamide gel, transferred onto a nitrocellulose membrane, and probed with LHK15 antibody. Lane 1, A-431 (vulval carcinoma line);lane 2,MCF-7 (breast carcinoma line);lane 3,TR 146 (epidermal carcinoma line);lane 4, HaCaT (immortalized epidermal keratinocyte line); and lane 5, primary human keratinocytes. (b) Detection of K6, K14, and K15 in a keratin extract of HaCaT cell line. Keratin polypeptides isolated from HaCaT cells were analyzed by immunoblotting. Lane 1, LHK6 for K6;lane 2,LL001 for K14;lane 3, LHK15 for K15.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 1999 The Society for Investigative Dermatology, Inc Terms and Conditions

3. Figure 2
Reactivity of the monoclonal antibody LHK15 with basal keratinocytes in stratified squamous epithelia of fet al and adult origins. Comparison of the K14 expression with that of K15 in human stratified epithelia. Unfixed frozen human tissue sections were reacted with LL001 for K14 (a, c, e, g, i) and with LHK15 for K15 (b, d, f, h, j) for 2–4h at room temperature. After washing, the sections were incubated first with fluoresceine-labeled goat anti-mouse followed by a propidium iodide solution before mounting. The tissues used were normal breast skin (a, b), esophagus (c, d), hair follicles (e, f), fet al epidermis (g, h), and fet al nail (i, j). Discontinuous staining of the basal layer by LHK15 in (b) is shown by arrows. Note the red staining of nuclei with propidium iodide. Scale bar: (a–d, g, h)50μm, (e, f, i, j)100μm.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 1999 The Society for Investigative Dermatology, Inc Terms and Conditions

4. Figure 3
K15 mRNA is primarily expressed in the basal keratinocytes of stratified squamous epithelia. Comparison of the K14 mRNA expression with that of K15 in stratified squamous epithelia. Unfixed frozen human tissue sections were fixed in 4% paraformaldehyde and processed for in situ hybridization using a highly specific cRNA probe for K14 (a, c, e) and K15 (b, d, f) as described in Materials and Methods. The tissues used were oral mucosa (a, b), palate (c, d), and skin (e, f). Expression of K15 mRNA (g) and protein (h) in hair follicles from a patient suffering from the recessive form of epidermolysis bullosa simplex. In this case both K14 alleles were naturally ablated and the K14 protein was undetectable. The separation of epidermis from the dermis due to skin blistering is marked by asterisks. The expression of K15 in the hair bulb that was absent in normal follicles (seeFigure 2fcan be clearly seen here. Scale bar: 100μm.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 1999 The Society for Investigative Dermatology, Inc Terms and Conditions

5. Figure 4
Downregulation of K15 in primary human keratinocytes undergoing differentiation in an organotypical culture. Primary human keratinocytes were cultured on a layer of human dermal fibroblasts growing on de-epidermised dermis as described in the Materials and Methods. The dermal plug was removed from the medium after 16d and sectioned in a cryostat. The sections were fixed in a mixture of acetone/methanol (1:1), dried in air, and incubated with primary antibodies for transglutaminase (a), loricrin (b), involucrin (c), K1 (d), K10 (e), K14 (f), K6 (g), K16 (h), and K15 (i). The sections were incubated with fluoresceine-labeled goat anti-mouse and propidium iodide before mounting. The staining of nuclei with propidium iodide is shown by red or yellow. Scale bar:100μm.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 1999 The Society for Investigative Dermatology, Inc Terms and Conditions

6. Figure 5
Expression of the K15 mRNA and protein are downregulated in hyperproliferative conditions. Unfixed frozen tissue sections from psoriatic epidermis (a, b) were immunostained with the monoclonal antibody LL001 (a) and with LHK15 (b). Hypertrophic scar samples (c, d) were probed by in situ hybridization using K14 (c) and K15 (d) cRNA probes as described in Materials and Methods section. Scale bar:100μm.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 1999 The Society for Investigative Dermatology, Inc Terms and Conditions