Specificity of oral immune priming in the red flour beetle Tribolium castaneum

Abstract

Immune specificity is the degree to which a host's immune system discriminates among various pathogens or antigenic variants. Vertebrate immune memory is highly specific due to antibody responses. On the other hand, some invertebrates show immune priming, i.e. improved survival after secondary exposure to a previously encountered pathogen. Until now, specificity of priming has only been demonstrated via the septic infection route or when live pathogens were used for priming. Therefore, we tested for specificity in the oral priming route in the red flour beetle, For priming, we used pathogen-free supernatants derived from three different strains of the entomopathogen,, which express different Cry toxin variants known for their toxicity against this beetle. Subsequent exposure to the infective spores showed that oral priming was specific for two naturally occurring strains, while a third engineered strain did not induce any priming effect. Our data demonstrate that oral immune priming with a non-infectious bacterial agent can be specific, but the priming effect is not universal across all bacterial strains.

The C. elegans GATA transcription factor elt-2 mediates distinct transcriptional responses and opposite infection outcomes towards different Bacillus thuringiensis strains

“…Invertebrates are excellent models to address this question because they rely exclusively on innate immunity to fight pathogen threats. While it is established that distinct signaling pathways regulate invertebrate defense responses to broadly different groups of pathogens [1][2][3], phenotypic evidence suggests that invertebrate defense responses can even be distinct between different strains of the same pathogen species [4][5][6][7][8][9][10][11]. However, only few studies directly tested how different strains of a pathogen affect the host immune response.…”

A multi‐faceted approach testing the effects of previous bacterial exposure on resistance and tolerance

“…Here, the phenomenon is often referred to as immune priming (Little & Kraaijeveld, ). The effects of priming can be broad, ranging from coarse specificity (e.g., Boman, Nilsson, & Rasmuson, ; Moret & Siva‐Jothy, ) to highly specific responses that differentiate at the level of bacterial strain (Futo, Sell, Kutzer, & Kurtz, ; Roth et al., ). Drosophila melanogaster , the model used in this study, shows some evidence of priming (Boman et al., ; Pham et al., ), although not towards all tested pathogens (Longdon, Cao, Martinez, & Jiggins, ; Pham et al., ).…”

Enhanced Immune Protection of Mud Crab Scylla paramamosain in Response to the Secondary Challenge by Vibrio parahaemolyticus

“…Violin plots are used to summarize the differences in gene expression in hemocytes and the hepatopancreas, respectively. All genes of the TLR signaling pathway or AMPs at different time points (6,9,72,174,177, and 240 h) show that the different expression (i) was higher in hemocytes than that in hepatopancreas, (ii) became more significant in the hepatopancreas from 9 h in the ICP, (iii) became more significant in hemocytes at all time points of the ICP, and (iv) was greater at 9 h of the ICP in the hepatopancreas and hemocytes ( Figures 4A, B).…”

“…The immune system of invertebrates has been considered to be nonspecific. However, increasing numbers of studies show that, if invertebrates are infected repeatedly by pathogenic microorganisms, a phenomenon similar to the immune memory found in vertebrates is observed (3,4,(6)(7)(8), but the priming effect is not universal across all bacterial strains (9). The improved survival and immune responses observed after secondary exposure to a pathogen encountered previously in invertebrates is defined as "the ability to store and recall information on previously encountered microbial communities or their components" (10) and is called "immune priming" (11), "specific immune priming" (12), or "quasi-immune response" (13).…”