Acute experimental autoimmune encephalomyelitis. Differences between T cell subsets in the blood and meningeal infiltrates in susceptible and resistant strains of guinea pigs.

The percentages of early (active, high affinity-rosetting), late (total) T cells and TG cells (suppressor T cells) were determined longitudinally in the blood and meningeal infiltrating cells of Strain 13 (susceptibility) and Strain 2 (resistant) animals inoculated for acute EAE and in guinea pigs of both strains in which the disease was suppressed with myelin basic protein (MBP) in incomplete Freund's adjuvant (IFA). Reactivity of T cells to MBP and oligodendrocyte protein was tested using the antigen-reactive T cell test. After inoculation for acute EAE, a transient increase in circulating early T cells was found during the latent period in Strain 13 guinea pigs only, while both strains showed a decrease in early T cells later on. Low values of circulating TG cells were more apparent in Strain 13 than Strain 2. In infiltrating cells of the meninges, early T cell values were significantly higher in the meninges than in the blood (P less than 0.01) in Strain 13, but were only slightly elevated in Strain 2 animals. TG cell levels in meningeal infiltrates were slightly higher than corresponding blood levels in both strains. In animals which were given a suppressive regimen of MBP/IFA, circulating early T cells rose initially and showed normal values later on in both strains of guinea pigs. TG cell levels were slightly more increased in strain 13 than strain 2. In comparison to blood values, early T cells were higher in the CNS in Strain 13, and lower in the CNS in Strain 2. TG cell levels were increased over blood values in both strains. These quantitative discrepancies in T cell subset between Strain 13 and Strain 2 guinea pigs which had been inoculated for EAE might reflect a difference in the cell-mediated immune response to white matter antigens which might be related to the variation in susceptibility to EAE.