I n 1955, Jackson described the existence of circulating cytoplasmic granules of polysaccharide-protein composition in the fibrogenic cells of bone, tendon, and cornea of the fowl embryo which were growing in tissue culture. Long-lasting metachromasia developed in these granules when toluidine blue or thionine was added to the culture medium. It was not specifically stated in that paper that th...

Histochemical reactions and radioautography were used to investigate the sequence of mast cell development in rat embryos. Mast cells arise ubiquitously in and are confined to the loose connective tissue in the embryo. The alcian blue-safranin reaction distinguishes between weakly sulfated and strongly sulfated mucopolysaccharides by a shift from alcian blue to safranin staining. Based on this ...

Purified cytoplasmic granules from cytotoxic rat large granular lymphocytes (LGL) tumors were cytolytic to erythrocytes, splenocytes, and a number of different lymphoid tumor cells. Granule concentrations of approximately 1 microgram/ml granule protein were adequate to lyse 100% of the erythrocytes, while the nucleated cells required up to 100 micrograms/ml granule protein to achieve complete l...