Estudio de la respuesta inmune humoral y celular en la infección y reinfección experimental de bovinos con Anaplasma marginal

Abstract

THE VARIATIONS OF PERIPHERAL BLOOD T CD2, CD4, AND CD8 LYMPHOCYTES, IGG ANTI-ANAPLASMA ANTIBODIES (ABS) AND INTERFERON GAMMA (IFN-G) IN SERA AND COMPLETE BLOOD CULTURE (CBC) FROM BOVINES EXPERIMENTALLY INFECTED OR NOT WITH THE SAME ANAPLASMA MARGINALE ISOLATE WERE EVALUATED. SEVEN 12 TO 14 MONTH OLD BOVINES WERE USED. FOUR (GROUP I) WERE INOCULATED INTRAVENOUSLY WITH 1 €” 108 PARASITIZED ERYTHROCYTES (PE)/ANIMAL, WHICH CONTAINED THE A. MARGINALE MORELOS ISOLATE, AT DAY 0, AND WITH 2 €” 108 PE, AT DAY 60; WHILE THE OTHER THREE (GROUP C) WERE NOT INFECTED. PERIPHERAL BLOOD SAMPLES AND SERA WERE COLLECTED FROM ALL ANIMALS TO EVALUATE PACKED CELL VOLUME (PCV), PERCENTAGE OF PARASITIZED ERYTHROCYTES (PEP), T CD2, CD4 AND CD8 LYMPHOCYTES BY CYTOFLUOROMETRY AS WELL AS ABS AND IFN-G BY ELISA. IN GROUP I, THE MAXIMUM AVERAGE PEP WAS 5.2% AT DAY 31 POSTINFECTION (P.I.), WHILE THE PCV REACHED AN AVERAGE OF 6% AT DAY 46 P.I. FOLLOWING REINFECTION (R.I.), THE PEP WAS 0 AND THE PCV WAS NORMAL. THE VALUES OF CD2 WERE SIMILAR IN BOTH GROUPS DURING THE STUDY; HOWEVER THE CD4 AND CD8 VALUES IN GROUP I DROPPED SIGNIFICANTLY (P < 0.05) AT DAY 45 P.I., LATER REACHING SIMILAR VALUES TO THOSE OF GROUP C. A SIGNIFICANT INCREASE (P < 0.05) IN FLUORESCENCE INTENSITY (FI) IN CD2 AND CD8 LYMPHOCYTES FROM GROUP I R.I. (DAYS 62 AND 83), WITH RESPECT TO THE FIOBTAINED IN LYMPHOCYTES FROM GROUP C, WAS OBSERVED. ABS LEVELS IN INFECTED BOVINES INCREASED ABOVE THE BASAL VALUES AND THOSE OF THE CONTROL ANIMALS, BEGINNING AT DAY 51 P.I. SIMILARLY, IFN-G LEVELS IN SERA AND CBC SUPERNATANT FROM INFECTED BOVINES WERE SIGNIFICANTLY HIGHER (P < 0.05), PARTICULARLY AFTER REINFECTION, THAN THOSE FROM THE NONINFECTED ANIMALS.