Absence of Carp's agent in sera of patients with multiple sclerosis in Japan.

A study was devised to test for Carp's agent in the sera of Japanese patients with multiple sclerosis (MS). The sera were obtained from 17 patients with definite MS and six patients with possible MS. Strain C3H mice were given an intraperitoneal injection of 0.1 mL of each serum. One week before and 1, 3, and 6 weeks after inoculation, blood drops from tail tip were smeared and polymorphonuclear leukocytes (PMNLs) were counted. Although the experimental animals were kept under careful control, substantial fluctuation in the number of PMNLs occurred, and the variations of PMNL count in the experimental groups were all within the normal range. We conclude that there is no Carp's agent in the sera of patients with MS in Japan.