A mechanistic insight into the cytomorphology of liver macrophages in tilapia (Oreochromis sp.)
*Srikanta Guria and Rahit Ali
Post Graduate Department of Zoology, Barasat Govt. College, Barasat, Kolkata-700124, West Bengal (India) *Corresponding author: Dr. Srikanta Guria, Assistant Professor, Post Graduate Department of Zoology, Barasat Govt. College, Kolkata-700124, West Bengal (India) E-mail: guriasrikanta@gmail.com, srikantaguria81@gmail.com
ABSTRACT
Macrophages are found primarily in the fish spleen and kidney, and to a lesser extent in liver. They are key cells for dealing with foreign particles. Liver is a target tissue for lesions related to chemical pollution. However, there is limiting literature available on the macrophages within the liver in fishes. Melano-macrophage centres (MMC), are normally located in the stroma of the tissue of the spleen, liver and the kidney. Melano-macrophage centres increase in size or frequency during environmental stress and chemical pollution. We aimed to characterize the morphological and functional aspects of liver-associated macrophages in tilapia. Tissues from liver were removed from tilapia (Oreochromis sp.) and mashed in (0·1) M phosphate buffer saline (pH 7·2) in presence of trypsin-EDTA. From cell suspension, adherent macrophages on glass slides were analyzed. Kidney and Liver tissues were processed for routine histological examination. Liver macrophages (LM) showed the property of phagocytosis. Tendency of cell fusion was noticed. Macrophage aggregates on glass slides and tissue sections were poorly, irregularly organized. Compared with the liver, macrophages (MACs) accumulations in the kidney tissues were larger in size and distinct. Hepatic alterations and the presence of large MMCs in the livers and necrotic macrophages immune cell agglomerate of fishes may be related to the high levels of heavy metal contamination and pollution.