rHuGM-CSF, as an adjuvant, elicits delayed-type hypersensitivity (DTH) responses to tetanus toxoid (tt) similar to those seen in animals immunized with a standard adjuvant. Rats were injected with Freund’s adjuvant (CFA) subcutaneously (sq), alum sq, rHuGM-CSF intradermally (id) or sq (5 μg), and phosphate-buffered saline (PBS) sq with tt at a concentration of 3 limit flocculation (Lf ) units. Immunizations were administered on 1 day only with no repeated administration of rHuGM-CSF. Six rats were included in each experimental group. Figure represents data collected from two separate experiments. Twenty days after immunization, a DTH response was measured in the immunized animals. Antigen was applied to rat ear and responses measured at 48 hours. Ear swelling of experimental compared with control ear was measured. Results are shown as the mean and standard deviation of measurements taken from each experimental group. (Reprinted with permission.145)