[1] Fundacao Oswaldo Cruz FIOCRUZ, Dept Imunol, Ctr Pesquisas Aggeu Magalhaes, Recife, PE, Brazil
[2] Inst Med Integral Prof Fernando Figueira, Oncol Pediatr, Recife, PE, Brazil
[3] Univ Sao Paulo, Div Imunol Clin, Dept Med, Fac Med Ribeirao Preto, BR-05508 Sao Paulo, Brazil