Earthworm leukocytes that are not phagocytic and cross-react with several human epitopes can kill human tumor cell lines.
Earthworm coelomocytes (leukocytes) effect cytotoxicity at significantly high levels against the NK-sensitive, human tumor cell line, K562, and the NK-resistant targets (U937, BSM, CEM). By cytofluorimetric analyses using mouse anti-human monoclonal antibodies and by morphological evaluations, two types of coelomocytes were identified: (1) small (8-11 micron) electron-dense cells (SC): CD11a+, CD45RA+, CD45RO+, CDw49b+, CD54+, beta 2-m+ and Thy-1+; (2) large (12-15 micron) electron-lucent cells (LC) that are negative for these markers. Both cell types were negative for other CD and MHC class I and class II markers. SC were active during recognition, rapidly binding to targets; LC were phagocytic. Release of 51Cr revealed rapid, significant, and equal levels of killing at 4 degrees, 20 degrees, and 37 degrees C. We propose that primitive NK-like activity appeared early in evolution.
Cossarizza
A
A
Department of Biomedical Sciences, University of Modena, Italy.
Cooper
E L
EL
Suzuki
M M
MM
Salvioli
S
S
Capri
M
M
Gri
G
G
Quaglino
D
D
Franceschi
C
C
D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D015415:Biomarkers; D002469:Cell Separation; D048429:Cell Size; D003602:Cytotoxicity, Immunologic; D005434:Flow Cytometry; D006649:Histocompatibility Antigens / Q000032:analysis; D006801:Humans; D007694:Killer Cells, Natural; D007962:Leukocytes / Q000145:classification / Q000276:immunology*; D009835:Oligochaeta / Q000276:immunology*; D010641:Phenotype; D013045:Species Specificity; D014407:Tumor Cells, Cultured
D015703:Antigens, CD; D015415:Biomarkers; D006649:Histocompatibility Antigens