Identification of a novel macrophage population in the normal mouse corneal stroma.
OBJECTIVE
To examine the normal murine corneal stroma for the presence of bone marrow-derived leukocytes.


METHODS
Wholemounts of paraformaldehyde-fixed corneal stroma from normal mice at 5 to 16 weeks of age were examined in single- and double-color immunomorphologic studies performed with confocal microscopy. The phenotype, morphology, distribution, and density of immunopositive cells were determined.


RESULTS
Numerous CD45(+) cells with pleomorphic and dendriform morphology were found within the pericentral and central region of the corneal stroma (200-300 cells/mm(2)). Dual-color immunostaining demonstrated that 100% of the CD45(+) cells coexpressed CD11b and 50% coexpressed F4/80. Approximately 30% of the total cells and 50% of the F4/80(+) cells coexpressed major histocompatibility complex (MHC) class II antigens. Very small to negligible numbers of cells expressed markers of dendritic cells (CD11c) or granulocytes (Ly6G). Markers for T-cells and NK cells were absent from the corneal stroma, indicating that all the cells identified in the stroma were of the myeloid lineage.


CONCLUSIONS
The normal murine corneal stroma contains a significant number of CD45(+) leukocytes. Most these cells express the CD11b marker, but not other dendrite, granulocyte, T-cell, or NK markers, placing them in the monocyte/macrophage lineage.
Brissette-Storkus
Cynthia S
CS
Department of Ophthalmology, Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Pittsburgh, PA 15213, USA.
Reynolds
Stephanie M
SM
Lepisto
Andrew J
AJ
Hendricks
Robert L
RL
D000818:Animals; D018845:CD11 Antigens / Q000378:metabolism; D002452:Cell Count; D003319:Corneal Stroma / Q000166:cytology*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D016130:Immunophenotyping; D017493:Leukocyte Common Antigens / Q000378:metabolism; D007962:Leukocytes / Q000166:cytology / Q000378:metabolism; D008264:Macrophages / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D018613:Microscopy, Confocal
D018845:CD11 Antigens; D017493:Leukocyte Common Antigens