The chemiluminescence activity of peripheral blood mononuclear cells during acute experimental allergic encephalomyelitis.

The spontaneous chemiluminescence activity (CL-A) of peripheral mononuclear cells (MNC) was examined in Lewis rats with acute experimental allergic encephalomyelitis (EAE), compared to rats immunized with complete adjuvant (n = 11) and healthy animals (n = 16). In rats with EAE, CL-A increased sharply 8-9 days after immunization (3420 +/- 3124 counts/10 s, n = 16) at the time of flattening of the weight curve. This CL-A peak was compared to that of animals immunized with complete adjuvant: 765 +/- 441 counts/10 s (P = 0.01) and healthy rats: 450 +/- 172 counts/10 s (P = 0.0001). After this initial peak in EAE rats, CL-A decreased almost to normal values when animals lost weight (746 +/- 251 counts, n = 19) and tail paralysis developed (557 +/- 251 counts/10 s, n = 15). CL-A increased again with the onset of paralysis of the extremities (1527 +/- 990 counts/10 s, n = 11), followed by a decrease as the clinical course deteriorated. Finally, CL-A approached normal values as the animals improved. A significant increase in the number of meningeal (P less than 0.01) and perivascular (P less than 0.01) cells in the CNS coincided with the initial CL-A peak. Gel filtration of the serum of rats with increased CL-A revealed at least one substance, with a molecular weight between 13,700 and 43,000 Da, which stimulated the CL-A of normal mononuclear cells.