Resumen de Valuación in vitro de la actividad de fagocitosis e inducción de apoptosis en neutrófilos bovinos frente a s. Aureus capsular mediante microscopía de campo claro y epifluorescencia
Valente Velázquez Ordóñez, N. Montoya García, Benjamín Valladares Carranza, H. Castañeda Vázquez, A. Hernández Beltrán
Neutrophils (PMN), is the first cellular defense line in bovine mastitis, S. aureus expressing the capsular exopolysaccharide is considered a virulence factor. The effect of the capsule on S. aureus phagocytosis and PMN apoptosis in vitro was evaluated in dairy cattle. The neutrophil phagocytosis index (PI) and apoptosis was evaluated by the methods of light microscopy stained with May Grünwald -Giemsa and epifluorescence staining wiht ethidium bromide and acridine orange. The results obtained for the PI for light microscopy were compact strain CC 6.06 ± 0.32, capsular strain CP5 5.06 ± 0.16 (p < 0.05). PI values by epifluorescence technique was: CC 7.51 ± 0.54 and CP5 5.12 ± 0.55 (p < 0.05). The percentage of apoptosis induction evaluated by light microscopy was: Positive Control C ( +) 97.56 ± 1.47 , Control negative C(-) 27.08 ± 2.18, CC 35.11 ± 2.87 and CP5 53.01 ± 8.03 (p < 0.05). The Apoptosis values using epifluorescent technique were: C(+) 95.47 ± 3.07 , C(-) 20.39 ± 2.00 , CC 26.47 ± 1.42 and CP5 46.90 ± 5.82 ( p <0.05). There were differences in the activity of in vitro phagocytosis between compact and diffuse capsular S. aureus types and its ability to induce apoptosis of bovine neutrophils.
