DIFFERENTIAL TISSUE EXPRESSION OF ANNEXIN-VIII IN HUMAN

The expression of Annexins V and VIII by human lung, liver, kidney, sk in, heart, uterus, spleen and skeletal muscle was investigated by ELIS A. All investigated tissues contained Annexin V. Its level varied with the tissue from around 5 mu g (skin) to approximately 120 mu g (splee n) per g of wet tissue. Contradistinctionally Annexin VIII expression was less ubiquitous and less abundant. Only lung, skin, liver and kidn ey expressed Annexin VIII. Its levels were approximately 100-fold less then the Annexin V levels. Immunohistochemical analysis of lung secti ons revealed Annexin VIII presence exclusively in the endothelia. Anne xin V and VIII levels of cultured human umbilical vein endothelial cel ls, human arterial smooth muscle cells, human lung fibroblasts and HeL a cells were measured by ELISA. All cell types expressed Annexin V whe reas only HeLa cells had detectable levels of Annexin VIII. The result s indicate a tissue specific expression of Annexin VIII by lung endoth elium, suggesting a highly specialised function.