Stepwise Maturation of Lytic Granules during Differentiation and Activation of Human CD8+ T Lymphocytes
Figure 2
Isolation of lytic granules from CTL.
(A) Schematic representation of the simplified procedure used to isolate a vesicular extract enriched in lytic granules. (B) Aliquots corresponding to the CTL homogenate, the P1 pellet, the supernatant SN2 and the P2 pellet were immunoblotted with an antibody specific for GrB. (C) Electron micrograph of the P2 pellet fraction (Magnification, 40 000×). Distinct vesicles can be observed: tiny droplets (I), dark core bodies surrounded by lipid bilayers (II), larger granules containing small internal vesicles (III), granules containing multivesicular bodies (MVB).