PURPOSE:We already demonstrated that subcutaneous sensitization with Ovalbumin (OVA) induce generation of specific IgE antibodies and modifications of immune cells populations from bronchial mucosa in rabbit. The aim of the study is characterization of CD5 and α-chain-positive cell population in lung perivascular infiltrate from OVA sensitized and challenged rabbits.
METHODS:New Zealand white rabbits were divided into three groups: G1 (n=8): normal control; G2 (n=10): subcutaneous sensitized with OVA; G3 (n=10): subcutaneous sensitized and inhalatory challenged with OVA. Four hours after challenge animals were sacrificed and obtained samples were processed for immunohistochemistry with the following monoclonal antibody: mouse anti-rabbit CD5 and α-chain. Avidin-biotin-peroxidase system was used as detection kit. Cells were counted in 200 high power fields per group.
RESULTS:Data were expressed as arithmetic mean and standard deviation. CD5: G1: 4.6 (SD 1.7); G2: 5.5 (SD 1.4); G3: 10.4 (SD 2.8). (G3 vs G1 and G2 p<0.00l). α-chain G1: 3.6 (SD 0.8); G2: 1.4 (SD 0.3); G3: 12.2 (SD 2.0). (G3 vs. G1 and G2 p<0.00l). Specific anti-OVA-IgE levels were evaluated by positive passive cutaneous anaphylaxis test (PCA) at 160 fold dilutions.
CONCLUSION:An increase in number of CD5 and α-chain-positive cell after inhalatory challenge is observed as compared to normal control and sensitized animals without challenge. We conclude that systemic sensitization with soluble antigen and inhalatory challenge induces modifications in number of immune cells populations in lung perivascular infiltrate from rabbits.
CLINICAL IMPLICATIONS:Sensitization with soluble food allergen as OVA induced modifications in perivascular infiltrate that could generate functional alterations.
DISCLOSURE:Miguel Vinuesa, No Financial Disclosure Information; No Product/Research Disclosure Information