Movement of cell surface immunoglobulin (Ig) in guinea pig B cells and lymphocytic leukemia cells as observed by light microscopy and scanning and transmission electron microscopy.

: The distribution and regeneration of immunoglobulin (Ig) of guinea pig leukemia cells were investigated through the use of ferritin labeling and scanning electron microscopy. Throughout this work, correlative light microscopy using fluorescein label and transmission electron microscopy using ferritin label were used. The cells used in this study were lymphocytic leukemia cells, an acute (L2C) and a chronic (KSL) form, and normal B cells obtained from Sewall Wright strain 2 guinea pigs. Distinct differences in the movement and regeneration of cell surface Ig were observed when these cells were compared. Both L2C and KSL cells were slower to cap than normal B cells which formed a well-organized single patch. The cells endocytosed the label rapidly and either processed or shed the label within 24 hours except for the L2C cells which had retained internalized label after 24 hours. Regeneration of surface Ig was clearly demonstrated in all three cell types. The apparent similarities between these two lymphocytic guinea pig leukemias and similar reports of human leukemias strongly suggest that the L2C and KSL cells could provide excellent models for future studies of acute and chronic forms of this disease.