TY - JOUR T1 - Interaction of Microspheres with Blood Constituents: I. Uptake of Polystyrene Spheres by Monocytes and Granulocytes and Effect on Immune Responsiveness of Lymphocytes JF - PDA Journal of Pharmaceutical Science and Technology JO - PDA J Pharm Sci Technol SP - 210 LP - 217 VL - 37 IS - 6 AU - M. Kanke AU - I. Sniecinski AU - P. P. Deluca Y1 - 1983/11/01 UR - http://journal.pda.org/content/37/6/210.abstract N2 - The interaction or association of polystyrene microspheres with blood constituents, and the effect on the immune response were studied with blood and tissue samples following i.v. administration of 1-, 3-, and 12-μm spheres into Beagle dogs. One- and 3-μm spheres were found in the lysosomes inside of the cytoplasm of monocytes and granulocytes with a residence time of up to at least 24 hr while the 12-μm spheres were observed outside of the monocytes and granulocytes. There was no evidence of any damage to the lysosomes or other cellular organelles and normal enzymatic function of the monocytes and granulocytes was maintained as evidenced by normal distribution of esterase enzymes in the cells. The effect of the microspheres on serum protein distribution was determined by analysis of protein fractions including gamma globulin between controls and samples and cell-mediated immune response was assessed by measuring the responsiveness of the peripheral blood lymphocytes to mitogenic stimulation. The response of T and B lymphocytes to pokeweed, phytohemagglutinin, and concanavalin A mitogens showed no change 7 days after microsphere administration of the 1- and 12-μrn sizes. The serum protein levels including gamma globulin were unchanged from control values indicating the spheres did not antigenically stimulate the immune response. ER -