Factors present in supernatants from antigen-stimulated CMV-seropositive donor PBMCs support chemoattraction of PBMCs. Results are shown for transmigrated populations from cell migration assays with coculture supernatants representative of a CMV-seropositive donor and -seronegative donor. PBMCs were loaded into the upper chambers of transwells to test migration into coculture supernatants as described in “Transwell migration assays and specific antibody neutralization assays.” Sample 1 was CMV-seropositive donor PBMCs + AECs + CMV antigen, 2 was CMV-seropositive donor PBMCs + AECs, 3 was CMV-seronegative donor PBMCs + AECs + CMV antigen, 4 was CMV-seronegative donor PBMCs + AECs, 5 was AEC cultures, resting, and sample 6 was RPMI/1% FCS. For each sample, 3 transmigration wells were set up, and the transmigrated populations were counted from each well independently. Results are shown as the mean (± SD) in cells per milliliter and are representative of 3 independent assays with different CMV-seropositive and -seronegative donor pairs compared in each.