Fig. 1.

The Th2 response to L. sigmodontis is initiated in the pre-patent period Systemic and local immune responses were examined to determine the timing and extent of the Th2 response to L. sigmodontis. (A) Infection of L. sigmodontis in BALB/c mice is illustrated with approximate times of molting and patency as well the anatomical location of the various life cycle stages, adapted from [19]. Time points for the experiments (Days 1, 5, 14, 36, 42, and 60 post-infection) are denoted with small arrows. The pre-patent period is defined as the period after the adults are established in the pleural cavity prior to microfilariae appearing in the blood. (B) Levels of total IgE, total IgG1 and total IgG2 were determined by ELISA in the plasma of infected (n=5) or control (n=5) mice. Total IgE values are expressed in ug/ml and total IgG1 and total IgG2 values are expressed as ODs. (C) The mean levels of IL-5 (expressed as pg/ml) in the plasma from 5 control (solid line) and 5 infected mice (dotted line). All statistically significant differences (p<0.05) are indicated with a star. (D) Cytokine levels (IL-4, Il-5, IL-10, IL-13, IL-17 and TNF-α) were determined in concentrated and pooled pleural lavage fluid by Luminex™ for control mice (black bars) and infected mice (gray bars). All values are expressed as pg/ml.