RT Journal Article SR Electronic T1 Honey bee drones maintain humoral immune competence throughout all life stages in the absence of vitellogenin production JF The Journal of Experimental Biology JO J. Exp. Biol. FD The Company of Biologists Ltd SP 1313 OP 1322 DO 10.1242/jeb.065276 VO 215 IS 8 A1 Gätschenberger, Heike A1 Gimple, Olaf A1 Tautz, Jürgen A1 Beier, Hildburg YR 2012 UL http://jeb.biologists.org/content/215/8/1313.abstract AB Drones are haploid male individuals whose major social function in honey bee colonies is to produce sperm and mate with a queen. In spite of their limited tasks, the vitality of drones is of utmost importance for the next generation. The immune competence of drones – as compared to worker bees – is largely unexplored. Hence, we studied humoral and cellular immune reactions of in vitro reared drone larvae and adult drones of different age upon artificial bacterial infection. Haemolymph samples were collected after aseptic and septic injury and subsequently employed for (1) the identification of immune-responsive peptides and/or proteins by qualitative proteomic analyses in combination with mass spectrometry and (2) the detection of antimicrobial activity by inhibition-zone assays. Drone larvae and adult drones responded with a strong humoral immune reaction upon bacterial challenge, as validated by the expression of small antimicrobial peptides. Young adult drones exhibited a broader spectrum of defence reactions than drone larvae. Distinct polypeptides including peptidoglycan recognition protein-S2 and lysozyme 2 were upregulated in immunized adult drones. Moreover, a pronounced nodulation reaction was observed in young drones upon bacterial challenge. Prophenoloxidase zymogen is present at an almost constant level in non-infected adult drones throughout the entire lifespan. All observed immune reactions in drones were expressed in the absence of significant amounts of vitellogenin. We conclude that drones – like worker bees – have the potential to activate multiple elements of the innate immune response.