Genetic association between low expression phenotype of CD62L (L-selectin)in peripheral CD4(+) T cells and the thid (T-helper immunodeficiency) phenotype in the LEC rat

Genetic linkage analysis was performed between the low expression phenotype of peripheral CD4(+) T cells and the thid (T-helper immunodeficiency) phen otype using (BN x LEC)F-1 x LEC backcross progenies. In contrast to a previ ous result using a thid congenic strain that the low expression phenotype o f CD62L was not correlated with the thid phenotype, our result in this stud y indicated that the low expression phenotype of CD62L was genetically link ed with the thid phenotype. The discrepancy between the previous and presen t results may be due to the source of animals, congenic strain versus backc ross progenies. It is suggested by this study that the thid locus controls the expression level of CD62L in peripheral CD4(+) T cells.