Lymphocyte apoptosis in the inflammatory reaction around Taenia solium metacestodes in porcine cysticercosis.
In the current research, we report apoptosis of lymphocytes in the inflammatory reaction around metacestodes in muscle tissue from cysticercotic pigs. Two events, high metacestode viability (100%) and high cysteine protease activity were found to be closely related to a high phosphatydilserine expression by inflammatory lymphocytes (56%). Testing the RPMI medium used for washing away inflammatory cells from metacestodes with 100% viability, with the fluorescent substrate Z-Phe-Ala-AFC for measuring cysteine protease activity, significant fluorescent values were found. In contrast, tests performed with RPMI medium used for washing away inflammatory cells from metacestodes with 90% viability or less, showed low fluorescence values. Flow cytometry analyses of inflammatory cells obtained from four naturally cysticercotic pigs, and stained with Annexin-V/PI, showed lymphocytes expressing phosphatidylserine with values of 0, 6, 41 and 56% on their outer surfaces. Electron microscopy studies of inflammatory cells from metacestodes with 100% viability, showed lymphocytes with strangled and fragmented nuclei, and heterochromatin displaced to the nuclear periphery. In addition, DNA from these cells showed fragmentation in electrophoresis assays. Apoptosis of lymphocytes in the inflammatory reaction around Taenia solium metacestodes, might have been induced by the parasite cysteine protease, and may be involved in impairing cell-mediated immune responses in human and porcine cysticercosis.
Solano
Sandra
S
Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, México, DF 04510, Mexico.
Cortés
Isabel M
IM
Copitin
Natalia I
NI
Tato
Patricia
P
Molinari
José L
JL
D000818:Animals; D017304:Annexin A5; D017209:Apoptosis; D002478:Cells, Cultured; D003470:Culture Media; D003546:Cysteine Endopeptidases / Q000378:metabolism; D003551:Cysticercosis / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*; D053938:DNA Fragmentation; D005434:Flow Cytometry / Q000662:veterinary; D005456:Fluorescent Dyes / Q000378:metabolism; D008214:Lymphocytes; D018482:Muscle, Skeletal / Q000469:parasitology; D013552:Swine; D013553:Swine Diseases / Q000276:immunology* / Q000469:parasitology; D041201:Taenia solium / Q000201:enzymology* / Q000276:immunology
D017304:Annexin A5; D003470:Culture Media; D005456:Fluorescent Dyes; D003546:Cysteine Endopeptidases