journal of kerbala university الخلاصة. Aflatoxin B1 cause immune suppression especially in cellular immunity and decrease the number of T and B cells .The percentage of both CD4+ and CD8+ Tcells which are, in general, used as markers for helper and cytotoxic T cells ,are affected by aflatoxin B1 and showed lower percentage when injected with aflatoxin B1 four successive doses in mice ...