Cyclosporin A acts as a novel insecticide against Cry1Ac-susceptible and -resistant Helicoverpa armigera

Involvement of an Enhanced Immunity Mechanism in the Resistance to Bacillus thuringiensis in Lepidopteran Pests

“…A recombinant immunosuppressive wasp venom protein (rVPr1), derived from the venom gland of Pimpla hypochondriaca (an endoparasitic wasp) [ 160 ], can suppress the encapsulation response, thus increasing the susceptibility of Mamestra brassicae and Lacanobia oleracea to Bt [ 161 ]. Additionally, the inhibition of CaN activity (which may contribute to activate the IMD and Toll pathways to regulate AMP expression) by FK506 or CsA can increase the insecticidal activity of Bt toxins in Lepidopteran pests [ 40 , 41 , 162 , 163 , 164 ] and can even be used to manage Cry1Ac resistance in H. armigera [ 42 ]. Immune inhibitors that improve the insecticidal activity of Bt toxins can be used in Bt formulations.…”

“…Currently, the response mechanisms and immune resistance of insects is attracting worldwide attention to improve the insecticidal activity of Bt and managing insect resistance to Bt . In fact, understanding the host response mechanisms and immune resistance to Bt and Bt proteins will enable us to identify more ways of pest control and resistance management [ 40 , 41 , 42 , 43 , 44 , 45 ]. In this review, we will focus on the involvement of enhanced immune defense of insects against Bt , including the pattern recognition proteins for recognizing Bt , AMPs and their synthetic signaling pathways, the prophenoloxidase system, ROS generation, nodulation, encapsulation, phagocytosis, and cell-free aggregates.…”