Spatial Statistics for Epidermal Langerhans Cells
—Effects of Protopic^® Ointment 0.1% on the Spatial Distribution—

Toshihiko Numahara¹*, Masaharu Tanemura^2,3, Kiyo Numahara¹, Junko Moriue⁴, Yoshie Shirahige⁴, Ikumi Yokoi⁴ and Yasuo Kubota³

¹Numahara Hifuka (Medical Corporation), 2621 Hijidai, Toyonaka-cho, Mitoyo-shi, Kagawa 769-1501, Japan
²The Institute of Statistical Mathematics (ISM), 10-3 Midori-cho, Tachikawa, Tokyo 190-8562, Japan
³Department of Statistical Science, The Graduate University for Advanced Studies, 10-3 Midori-cho, Tachikawa, Tokyo 190-8562, Japan
⁴Department of Dermatology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
*E-mail address: numa_san@nifty.com

(Received February 13, 2008; Accepted March 4, 2009)

Abstract. Epidermal Langerhans cells (LCs) are dendritic cells abundant in the epidermis. LCs fulfill an essential role in skin immunology. We have applied spatial statistics to the study of LCs for the last 20 years. The immunosuppressive macrolide tacrolimus was discovered in 1984. Tacrolimus ointment has been available for atopic dermatitis patients in Japan since 1999 and in the U.S.A. since 2001. Three-week Protopic^® Ointment 0.1% (0.1% tacrolimus ointment) application to mice reduced both the density and spatial regularity of LCs. The estimated potential model functions were similar in control and tacrolimus groups, but the diameter, σ, of the tacrolimus group was slightly larger than the control. Although studies using LC suspension such as flow cytometry analysis have become the mainstream, there is information that can only be obtained based on the spatial pattern of LCs. Spatial statistics will provide a new viewpoint in dendritic cell studies.

Keywords: Spatial Statistics, Epidermal Langerhans Cells, Dendritic Cells, Tacrolimus, Protopic^® Ointment