Characterization of monoclonal antibodies to haemocyte types of the shrimp, Fenneropenaeus chinensis

Five monoclonal antibodies (MAbs) (1A7, 1C6, 1E4, 1G8, 2C3) against haemocytes of Fenneropenaeus chinensis (Osbeck, 1765) were produced by immunizing Balb/c mice, followed by indirect immunofluorescence assay tests (IIFAT). These showed specificity for more than one haemocyte type and for various haemocyte components of F. chinensis. Using Wright's staining and IIFAT with haemocyte monolayers prepared by sucrose gradient centrifugation, MAb 1A7, 1C6 reacted with membranes of hyalinocytes and the cytoplasm of semi-granulocytes, respectively; MAb 1E4 reacted with membranes and the cytoplasm of hyalinocytes, and with membranes of semi-granulocytes; MAb 1G8 reacted with haemocyte granules; and MAb 2C3 reacted with surface membranes of all haemocyte types. Western-blotting of haemocytes and haemocyte membrane analysis demonstrated that MAb 1G8 recognized an antigen of 96 kDa in haemocyte; that MAb 1E4 reacted with antigens of 88 kDa and 79 kDa in the haemocyte membrane; and that MAb 2C3 reacted specifically to a single membrane protein band with an approximate molecular weight of 153 kDa; however, there was no protein band detected by either MAbs 1A7, or 1C6.