LaeA and GliZ are transcription factors known to regulate the production of gliotoxin. LaeA is a universal regulator of secondary metabolite production in "Aspergillus" spp. LaeA influences the expression of 9.5% of the "A. fumigatus" genome, including many secondary metabolite biosynthesis genes such as nonribosomal peptide synthetases. The production of numerous secondary metabolites, including gliotoxin, were impaired in an LaeA mutant (ΔlaeA) strain. The ΔlaeA mutant showed increased susceptibility to macrophage phagocytosis and decreased ability to kill neutrophils "ex vivo". LaeA regulated toxins, besides gliotoxin, likely have a role in virulence since loss of gliotoxin production alone did not recapitulate the hypo-virulent ∆laeA pathotype.