Background to the existence of variation in the innate immune response in Galleria mellonella

Abstract. Pathogen abundance or pathogen genotypes may vary in space or time, resulting in fluctuations in immune responses. Genetic variation in the presence of biogeographically determined intraspecific diversity provides important information about the presence of such variations in a species widely used in laboratories and distributed worldwide, suggesting the presence of different immune responses against pathogens. Invertebrates have balancing selection with specific coevolution, in contrast to vertebrate AMPs, which have strong positive selection and a high probability of coevolution. Balancing selection on individual AMP genes in invertebrates may result in polymorphisms in amino acid sequences, potentially changing susceptibility to pathogens, the study of which is of high scientific significance. The purpose of the study was to investigate the potential existence of an extended haplotype (common to several individuals) or a separate haplotype encoding AMP among non-mammalian model organisms. Methods. The object of this study was a model organism (the greater wax moth Galleria mellonella). The analysis of G. mellonella genome assemblies was performed using 11 nuclear targets and the 16S ribosomal RNA region. Results. Six biogeographically distinct individuals were identified, obtained from both natural and artificial ecosystems: either from adults or larvae. Scientific novelty. The 11 nuclear targets encoding G. mellonella antimicrobial peptides and the 16S ribosomal RNA region helped to distinguish three population groups, which potentially supports the hypothesis of the existence of a variable innate immune response in this laboratory model in the presence of biogeographically determined intraspecific diversity.