IL4 and asthma: Total-immunoglobulin (Ig) E (tIgE), specific IgE (sIgE), and specific IgG1 (sIgG1) together with Interferon-γ (INF-γ, a Th1 cytokine) and interleukin-4 (IL-4, a Th2 cytokine) were assayed to verify at the molecular level the establishment of a rat asthma model.