Quantitative Assessment of Macrophages in the Muscularis Externa of Mouse Intestines

• Published in: Anatomical record (Hoboken, N.J. : 2007) N.J. : 2007), 2011-09, Vol.294 (9), p.1557-1565
• Main Authors: Mikkelsen, H.B., Larsen, J.O., Froh, P., Nguyen, T.H.
• Format: Article
• Language: English
• Subjects: adult; Animals; Animals, Newborn; CD169+ cells; Female; Histocompatibility Antigens Class II - metabolism; Immunoenzyme Techniques; intestine; Intestines - cytology; Intestines - metabolism; macrophages; Macrophages - cytology; Macrophages - metabolism; MHCII+ cells; Mice; Mice, Inbred C57BL; mouse; Muscle, Smooth - cytology; Muscle, Smooth - metabolism; Sialic Acid Binding Ig-like Lectin 1 - metabolism; stereology; young
• ISSN: 1932-8486; 1932-8494
• DOI: 10.1002/ar.21444

Quantification of intestinal cells is challenging for several reasons: The cell densities vary throughout the intestines and may be age dependent. Some cell types are ramified and/or can change shape and size. Additionally, immunolabeling is needed for the correct identification of cell type. Immunolabeling is dependent on both up‐ and down‐regulation of the antigen being labeled as well as on the primary and secondary antibodies, the fixation, and the enhancement procedures. Here, we provide a detailed description of immunolabeling of CD169+ cells and major histocompatibility class II antigen (MHCII+) cells and the subsequent quantification of these cells using design‐based stereology in the intestinal muscularis externa. We used young (5‐weeks‐old) and adult (10‐weeks‐old) mice. Cell densities were higher in jejunum‐ileum, when compared with colon. In jejunum/ileum, the cell densities increased in oral‐anal direction in adults, whereas the densities were highest in the midpart in young animals. In colon, the cell densities decreased in oral‐anal direction in both groups of animals. Except for the density of MHCII+ cells in colon, the cell densities were highest in young animals. Densities of CD169+ and MHCII+ cells did not differ, except in the colon of young animals where the CD169+ density was almost twice as high as the MHCII+ density. CD169 and MHCII antigens seem to be expressed simultaneously by the same cell in jejunum/ileum. We conclude that cell densities depend on both the age of the mouse and on the location in the intestines. Anat Rec, 2011. © 2011 Wiley‐Liss, Inc.