IG LIGHT CHAIN GENE REARRANGEMENT AND CHROMOSOMAL ABNORMALITY IN THE LAMA EARLY B-LINEAGE TUMOR OF THE RAT

In the rat, few lymphoid tumours have been described so far. At the previous Germinal Centre Conference, J. Rozing and coworkers (1) reported on LAMA, a transplantable tumour that arose spontaneously in a ♂ (A0xBN)F1 rat. From this study of surface antigens and mitogen reactivity it was tentatively proposed that LAMA was a pre-B leukemia, opening up possibilities in the rat for studies of B cell differentiation events at the molecular and cellular level. On the other hand, LAMA might serve as an in vivo tumour model in the rat. Here we present data on 1) the antigenic phenotype, 2) Ig light chain gene rearrangement and 3) the karyotype of LAMA