Thioperamide improves the symptoms of allergic mice through the induction of regulatory T lymphocytes in lung

AMARAL MARÍA M; ALVAREZ ROMINA; GEFFNER, JORGE; VERMEULEN, MÓNICA

Buenos Aires

Congreso; First French - Argentine Immunology Congress LVIII Reunión Anual de la Sociedad Argentina de Inmunología. XIII Jornada Científica del Grupo Rioplatense de Citometría de Flujo. 3º Jornadas Argentinas de Inmunodeficiencias Primarias (SAP); 2010

First French - Argentine Immunology Congress LVIII Reunión Anual de la Sociedad Argentina de Inmunología. XIII Jornada Científica del Grupo Rioplatense de Citometría de Flujo. 3º Jornadas Argentinas de Inmunodeficiencias Primarias (SAP)

Histamine (HIS) is one of the most important mediators in the development of allergic reactions. Historically, the pro-inflammatory effect of the amine was associated to its action on H1 receptors; however the use of antagonists for this receptor showed to be ineffective in the treatment of allergic diseases. In recent years, it was assigned an important role in these pathologies to H4R, which is not clear yet. In a previous work, we demonstrated that the injection of immature dendritic cells (DC) treated with HIS promoted the severity of allergic symptoms through the increase of TCD8+ Tc2 lymphocytes. Here, we decided to evaluate the role of H3R/H4R in allergy using thioperamide (Thi), an antagonist of these receptors, on DC. For this purpose, we use a known murine model of OVAinduced airway inflammation. After 15 days of OVA challenge, mice were injected intratracheally with PBS, DC (5x105 ), DC treated with 0.1µM HIS 30 min at 37°C (5x105 ) or DC treated with 10 µM Thi 30 min at 37°C (5x105 ). 21 days later we obtained the lungs of allergic mice and the suspension of cells were purified by negative selection by using a PAN T antibody. Surprisingly, we found a higher recruitment of regulatory CD4+CD25+Foxp3+ T cells in the lung of allergic mice injected with DCThi (mean of positive cells %±SEM, DCThi: 0.72±0.02 vs. PBS: 0.40±0.11;DC: 0.65±0.05; DCHIS: 0.41±0.05; *p