Physiological responses of a cold-water shrimp, Pandalus borealis to bacterial lipopolysaccharide and synthetic double-stranded RNA, poly I:C

The effects of two pathogen-associated molecular patterns (PAMPs), namely, bacterial lipopolysaccharide (LPS) and double-stranded RNA, poly I:C on selected physiological response parameters in the hemolymph of a cold-water shrimp, Pandalus borealis were studied. Most of the tested immune factors were affected after intramuscular injection with the PAMPs. Total protein concentration in the hemolymph was significantly upregulated upon injection with the test substances. There was a significant reduction in the total hemocyte counts of the PAMPs-injected groups at 12 h after injection, but no significant differences were observed 24 h thereafter. Myeloperoxidase activity, total antioxidant capacity (TAC), total glucose and phenoloxidase (PO) activity were transiently upregulated (12-h post-injection) in the treated groups but no significant differences were observed at 24 h after injection. Significant upregulation in the alkaline phosphatase activity was seen in the PAMPs-injected groups at 24-h post-injection. There were low levels of activity in the antibacterial enzymes, lysozyme and antiprotease and these were significantly downregulated in the groups injected with the test substances. These results suggest that cold-water shrimps are also capable of mounting an immune response upon exposure to PAMPs and P. borealis could serve as a useful organism to elucidate immune mechanisms among cold-water crustaceans.

► We described the responses of Pandalus borealis to PAMPs.
► Most of the immune factors were affected after injection with PAMPs.
► Cold-water shrimps are capable of mounting an immune response against PAMPs.