Antibacterial and anti-inflammatory activities of the immune-challenged silkworm (Bombyx mori) hemolymph with Lactobacillus cell wall extracts: Immune-challenged silkworm hemolymph

Insects have been used by humans as food and traditional medicines for many years. Their antimicrobial and anti-inflammatory activities are a main focus of medicinal insect research. In a previous study, hemocyte extracts prepared from Bombyx mori larvae were found to have anti-inflammatory effects. Therefore, we injected Lactobacillus cell wall extracts dorsolaterally into the hemocoel to increase antimicrobial peptides produced by silkworm larva. The best overall antimicrobial activities were observed against E. coli after injection of 10 mu L hemolymph from immune-challenged larvae, although the tested extract did not affect the cell proliferation rate. The effects of the immune-challenged B. mori hemolymph on anti-inflammatory pathways were determined using reverse transcription quantitative polymerase chain reaction and western blotting to assess the expression of pro-inflammatory molecules in macrophage-like human monocytic leukemia THP-1 cells following treatment with phorbol myristate acetate. The results demonstrated that the hemolymph of immune-challenged silkworms had antibacterial and anti-inflammatory effects. The effects of silkworms with immune-challenged hemolymph could facilitate the development of new types of functional foods, feed additives, and biomaterials with antibacterial and anti-inflammatory properties.