PERSONAL DE APOYO
BATALLA Estela
congresos y reuniones científicas
Título:
Toxoplasma Gondii AND PROTECTION AGAINST ALLERGIC SENSITIZATION
Autor/es:
BATALLA, E; MARTIN V; ROMERO Y; PIAZZÓN I; GOLDMAN A
Lugar:
Ciudad de Córdoba, Argentina.
Reunión:
Congreso; VII Congreso Latinoamericano de Inmunología, ALAI; 2005
Institución organizadora:
ALAI
Resumen:
Respiratory allergy is less frequent in people exposed to orofecal and foodborne microbes such as Toxoplasma gondii and hepatitis A virus (BMJ 2000,320:412), but not to viruses transmitted through other routes. Infection with T. gondii induces a strong cell-mediated immunity with a highly polarized Th1 response in early stages of infection (J.Immunol.1994,153:2533). We hypothesized that T. gondii infection diminishes the development of respiratory allergy. One week before allergic sensitization (day –7), adult BALB/c mice were orally infected with T. gondii (15 oocysts). They were then sensitized with two i.p. injections of OVA (days 0 and 7) before aerosol challenge (days 14-16). We evaluated allergic airway inflammation (AI) (differential count in bronchoalveolar lavage (BAL) and lung histology), serum IgE, and IgG1 OVA-specific antibodies, and IL-4 (Th2) secreted by OVA-stimulated thoracic lymph node cells. Infection was confirmed by measuring T. gondii specific antibodies.   Group IL-4 (pg/ml) BAL eos (%) IgE (ng/ml) IgG1 (µg/ml) T. gondii /OVA 18,2±0,3* 6,9±3,4* 971,0±322,6* 50,6±12,2* sham /OVA 707,2±93,7 67,9±7,4 3244,1±390,6 298,3±25,9 T. gondii /sham <15,5 2,8±1,2 <78 <5,3x10-4 sham /sham ND 0 <78 <5,3x10-4   X±SEM. *p<0,05 vs sham/OVA sensitized group. Histopathology showed a diminished allergic airway inflammation and goblet cell hyperplasia in OVA-sensitized mice previously infected with T. gondii. Parasite infection substantially blocked development of AI in adult BALB/c mice.