Abstract
Purpose::
To characterize the presence of hematopoietic cells, T cell and myeloid subsets, in human choroid with and without drusen.
Methods::
Seven posterior poles (78±12 years, range 55-91 years) were obtained from an eye bank within 48 hours post mortem and fixed in 100 percent ethanol. Macular biopsies of the posterior poles were embedded in OCT, and sectioned (6 microns). Two ophthalmologists examined the eye cups and an ocular pathologist examined H&E sections to determine if features consistent with drusen. Stained frozen sections immunochemically for CD4 (T helper cells), CD8 (cytotoxic T cells), CD14 (myeloid cells) and CD45 (hematopoietic cells). Each cell type was counted and expressed as the number of stained cells divided by the total number of cells counted on a minimum of three sections from each eye.
Results::
Three eyes were devoid of drusen, three contained drusen, and one eye contained a fibrovascular scar (FVS). In the absence of drusen, the percentage of cells stained for CD4, CD8, CD14 and CD45 was 6.1±5.1, 3.8±0.1, 4.0±4.4 and 25±7.7, respectively. In the drusen-containing eyes, the corresponding percentages were 8.1±3.4 (CD4), 6.0±1.5 (CD8), 2.5±0.6 (CD14) and 29±5.8 (CD45), respectively. In the FVS eye, the corresponding percentages were 1.9 (CD4), 4.1 (CD8), 0.0 (CD14) and 11 (CD45)
Conclusions::
Human choroid contains considerable numbers of hematopoietic cells. In this analysis, we found no significant difference between eyes with and without drusen. In the FVS eye, we found fewer lymphocytes in or around the scar. These results can provide baseline values for future studies of immune cells in human choroid.
Keywords: choroid • immunohistochemistry • inflammation