C4.4A and Haldisin are expressed in normal skin and appendages. Neighboring sections of normal human skin were stained using our polyclonal rabbit antibodies against C4.4A (A, C, E, G) and Haldisin (B, D, F, H). In the epidermis, C4.4A is primarily expressed in stratum spinosum (A) whereas the most prominent Haldisin expression is observed in stratum granulosum (B). In accordance with this, C4.4A is expressed in the suprabasal layer of the outer and inner root sheaths of the hair follicle (C), and in the epidermis of the sebaceous gland (E). Haldisin expression is observed in the inner root sheath of the hair follicles (D) and the granular layer of the sebaceous glands (F). In the sweat glands, C4.4A is expressed in ducts (G) and Haldisin in the gland structures (H). Insets show higher power micrographs of C4.4A and Haldisin expression in the hair follicle (panels C and D) and in the ducts and secretory structures of the sweat gland (panels G and H). d: dermis; sb: stratum basale; ss: stratum spinosum; sg: stratum granulosum; sc: stratum corneum; closed arrows: outer root sheath; open arrows: inner root sheath. Scale (A, B), 15 µm; (C–F), 100 µm; (G, H), 80 µm.