Cellular immune response of the Asian corn borer, Ostrinia furnacalis (Lepidoptera: Pyralidae), to infection by the entomopathogenic fungus, Beauveria bassiana

Abstract

Abstract. The term cellular immune response refers to haemocyte-mediated responses, including phagocytosis, nodulation, and encapsulation. In the present study, we identifi ed fi ve types of circulating haemocytes in larvae of the haemolymph of the Asian corn borer, Ostrinia furnacalis (Guenée), including granulocytes, oenocytoids, plasmatocytes, prohaemocytes, and spherulocytes. The relative number of total free haemocytes per larva decreased signifi cantly 0.5, 24, and 36 h after the injection of Beauveria bassiana conidia. Upon conidia challenge, both phagocytosis and nodulation were observed in the collected haemolymph from O. furnacalis larvae. In addition, plasma was found to be necessary for both phagocytosis and nodulation. Therefore, we here confi rm that phagocytosis and nodulation are involved in O. funacalis larvae during their fi ght against infection by B. bassiana, and further, that the cellular immune response of O. furnacalis helps eliminate the invading organisms despite the fact that not all the fungal conidia are killed.

PLA2 mediates the innate immune response in Asian corn borer, Ostrinia furnacalis

“…Conidia were separated from other mycelial structures by passing the mixture through a sterile funnel packed with autoclaved glass wool (Shen et al, 2016). Freshly prepared conidia were used for all experiments.…”

“…A strategy for suppressing O. furnacalis larvae using entomopathogenic fungi such as Beauveria bassiana has been proposed (Wagner & Lewis, 2000). In our previous work, we explored the interaction between B. bassiana and the immune response of O. furnacalis (Chu et al, 2015;Shen et al, 2016). However, it is still unknown whether the eicosanoid pathway is involved in this interaction.…”

Classification and characterization of immune haemocytes in the larvae of the Indian fritillary, Papilio hyperbius (Lepidopetra: Nymphalidae)

“…All of these haemocytes occur in Lepidoptera, although it is likely that each species has a distinct set. For example, the silkworm (Bombyx mori) has fi ve types of haemocyte: prohaemocytes, plasmatocytes, granulocytes, spherulocytes and oenocytoids (Lavine & Strand, 2002;Ribeiro & Brehelin, 2006;Strand, 2008) and the Asian corn borer (Ostrinia furnacalis), fi ve types, among which granulocytes are the most important (Shen et al, 2016). It is not easy to identify and classify the haemocytes in insects.…”

Pleiotropic immunoregulation by growth‐blocking peptide in Ostrinia furnacalis

“…Insects have developed ways to recognise microbes through pattern recognition receptors that bind pathogenassociated molecular patterns and stimulate cellular and humoral immune responses (Chen et al, 2014(Chen et al, , 2016Shi et al, 2023;Wu & Yi, 2018). Cellular responses involve phagocytosis, encapsulation and hemocyte nodulation while humoral responses include antimicrobial peptide (AMP) induction and prophenoloxidase (PPO) activation (Chen, Song, et al, 2022;Shen et al, 2016). The pathways for AMP induction vary among host insects.…”