MUC4 and infection: PAO1 lung inoculation induced two opposite expression patterns of Muc5b and Muc4: Muc5b is highly upregulated with a peak at day 4 showing a suppressive effect of n-3 PUFAs on the Muc5b response to the infection while Muc4 expression decreased to the lowest level at days 1 or 4 for sterile beads and at day 7 for Pseudomonas-laden agarose beads.