A Strikingly Constant Ratio Exists Between Langerhans Cells and Other Epidermal Cells in Human Skin. A Stereologic Study Using the Optical Disector Method and the Confocal Laser Scanning Microscope1  Jürgen Bauer, Friedrich A. Bahmer, Jürgen Wörl, Winfried Neuhuber, Gerold Schuler, Manigé Fartasch  Journal of Investigative Dermatology  Volume 116, Issue 2, Pages 313-318 (February 2001) DOI: 10.1046/j.1523-1747.2001.01247.x Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 1 Reference section: section 3 of the set of six parallel optical sections. Unbiased counting frame superimposed: 140 μm × 200 μm area for Langerhans cells, and 140 μm × 20 μm area for other epidermal cells counting. Fully drawn lines are exclusion lines; inclusion lines are dashed. Point grid for the determination of the area covered by propidium iodide stained epidermis. Note the four Langerhans cells transected. Other epidermal cells surrounded by CD1a-reactive dendrites are characterized by a perinuclear rim of unstained cytoplasm (double arrow). Sections 1, 2, 4, and 6 are used for an easier and unambiguous identification of the Langerhans cells nuclei. Journal of Investigative Dermatology 2001 116, 313-318DOI: (10.1046/j.1523-1747.2001.01247.x) Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 2 Lookup section: section 5 a known distance h = 3 μm apart from section 3. Only the single Langerhans cell marked with an arrow in Figure 1 is counted, because its nucleus is transected by section 3 and not by section 5. The other epidermal cells are counted the same way. If all Langerhans cells in section 3 were counted, their number would be overestimated by 300%. Journal of Investigative Dermatology 2001 116, 313-318DOI: (10.1046/j.1523-1747.2001.01247.x) Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 3 Number of other epidermal cells and corresponding number of Langerhans cells per mm2 of skin surface for the eight investigated patients with a coefficient of correlation of 0.952. Linear regression showing a fixed ratio of 1–52.88. Journal of Investigative Dermatology 2001 116, 313-318DOI: (10.1046/j.1523-1747.2001.01247.x) Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions