To determine whether expression of CagA in the Drosophila midgut is sufficient to alter host immune signaling pathways, we assayed activation of the Drosophila intestinal NF-kB pathway, the immune deficiency (IMD) pathway, by measuring expression of pathway-specific target genes encoding antimicrobial peptides, Diptericin, Attacin and Defensin [22,23]. Here, NFKB1 is linked to Immunodeficiency.