ACCUMULATION OF IMMUNOMODULATORY LAMINARAN (BETA(1,3)-D-GLUCAN) IN THE HEART, SPLEEN AND KIDNEY OF ATLANTIC COD, GADUS-MORHUA L

The tissue distribution of H-3- and FITC-laminaran in Atlantic cod, Ga dus morhua L., was investigated after intravenous administration. Liqu id scintillation counting and whole-body autoradiography revealed a su bstantial accumulation of H-3-labelled laminaran in the heart througho ut the experimental period (1 h to 12 days). High amounts of the immun omodulator were also present in the spleen, anterior kidney and poster ior kidney during the study. Renal excretion and intestinal exsorption were the main elimination pathways. Fluorescence microscopic examinat ion revealed accumulation of FITC-labelled laminaran in macrophages in the kidney and ellipsoid sheath cells (macrophages and reticular cell s) in the spleen. Furthermore, endothelial entrapment in the heart was pronounced. Endothelial cells in the kidney also contained the FITC-l abelled immunomodulator. Immunohistochemical analysis, using anti-beta (1,3)-D-glucopyranose antibody, also showed endothelial uptake of lami naran in the heart. The present investigation shows that laminaran acc umulates and is retained in immunologically relevant cells in the Atla ntic cod.