The Drosophila lymph gland, the larval hematopoietic organ comprised of prohemocytes and mature hemocytes, has been a valuable model for understanding mechanisms underlying hematopoiesis and immunity. Three types of mature hemocytes have been characterized in the lymph gland: plasmatocytes, lamellocytes, and crystal cells, which are analogous to vertebrate myeloid cells, yet molecular underpinnings of the lymph gland hemocytes have been less investigated. Here, we use single-cell RNA sequencing to comprehensively analyze heterogeneity of developing hemocytes in the lymph gland, and discover previously undescribed hemocyte types including adipohemocytes, stem-like prohemocytes, and intermediate prohemocytes. Additionally, we identify the developmental trajectory of hemocytes during normal development as well as the emergence of the lamellocyte lineage following active cellular immunity caused by wasp infestation. Finally, we establish similarities and differences between embryonically derived- and larval lymph gland hemocytes. Altogether, our study provides detailed insights into the hemocyte development and cellular immune responses at single-cell resolution.
References
Banerjee, U., Girard, J. R., Goins, L. M. & Spratford, C. M. Drosophila as a genetic model for hematopoiesis. Genetics 211, 367–417 (2019).
[PMID: 30733377]
Crozatier, M. & Vincent, A. Drosophila: a model for studying genetic and molecular aspects of haematopoiesis and associated leukaemias. Dis. Model Mech. 4, 439–445 (2011).
[PMID: 21669932]
Gold, K. S. & Bruckner, K. Drosophila as a model for the two myeloid blood cell systems in vertebrates. Exp. Hematol. 42, 717–727 (2014).
[PMID: 24946019]
Kocks, C. et al. Eater, a transmembrane protein mediating phagocytosis of bacterial pathogens in Drosophila. Cell 123, 335–346 (2005).
[PMID: 16239149]
Kurucz, E. et al. Nimrod, a putative phagocytosis receptor with EGF repeats in Drosophila plasmatocytes. Curr. Biol. 17, 649–654 (2007).
[PMID: 17363253]
Lebestky, T., Chang, T., Hartenstein, V. & Banerjee, U. Specification of Drosophila hematopoietic lineage by conserved transcription factors. Science 288, 146–149 (2000).
[PMID: 10753120]
Gajewski, K. M. et al. Identification of a crystal cell-specific enhancer of the black cells prophenoloxidase gene in Drosophila. Genesis 45, 200–207 (2007).
[PMID: 17417793]
Binggeli, O., Neyen, C., Poidevin, M. & Lemaitre, B. Prophenoloxidase activation is required for survival to microbial infections in Drosophila. PLoS Pathog. 10, e1004067 (2014).
[PMID: 24788090]
Rizki, R. M. & Rizki, T. M. Selective destruction of a host blood cell type by a parasitoid wasp. Proc. Natl Acad. Sci. USA 81, 6154–6158 (1984).
[PMID: 6435126]
Honti, V., Csordas, G., Kurucz, E., Markus, R. & Ando, I. The cell-mediated immunity of Drosophila melanogaster: hemocyte lineages, immune compartments, microanatomy and regulation. Dev. Comp. Immunol. 42, 47–56 (2014).
[PMID: 23800719]
Anderl, I. et al. Transdifferentiation and proliferation in two distinct hemocyte lineages in Drosophila melanogaster larvae after wasp infection. PLoS Pathog. 12, e1005746 (2016).
[PMID: 27414410]
Sorrentino, R. P., Tokusumi, T. & Schulz, R. A. The Friend of GATA protein U-shaped functions as a hematopoietic tumor suppressor in Drosophila. Dev. Biol. 311, 311–323 (2007).
[PMID: 17936744]
Galloway, J. L. & Zon, L. I. Ontogeny of hematopoiesis: examining the emergence of hematopoietic cells in the vertebrate embryo. Curr. Top. Dev. Biol. 53, 139–158 (2003).
[PMID: 12510667]
Evans, C. J., Hartenstein, V. & Banerjee, U. Thicker than blood: conserved mechanisms in Drosophila and vertebrate hematopoiesis. Dev. Cell 5, 673–690 (2003).
[PMID: 14602069]
Mandal, L., Banerjee, U. & Hartenstein, V. Evidence for a fruit fly hemangioblast and similarities between lymph-gland hematopoiesis in fruit fly and mammal aorta-gonadal-mesonephros mesoderm. Nat. Genet. 36, 1019–1023 (2004).
[PMID: 15286786]
Jung, S. H., Evans, C. J., Uemura, C. & Banerjee, U. The Drosophila lymph gland as a developmental model of hematopoiesis. Development 132, 2521–2533 (2005).
[PMID: 15857916]
Krzemien, J., Oyallon, J., Crozatier, M. & Vincent, A. Hematopoietic progenitors and hemocyte lineages in the Drosophila lymph gland. Dev. Biol. 346, 310–319 (2010).
[PMID: 20707995]
Krzemien, J. et al. Control of blood cell homeostasis in Drosophila larvae by the posterior signalling centre. Nature 446, 325–328 (2007).
[PMID: 17361184]
Mandal, L., Martinez-Agosto, J. A., Evans, C. J., Hartenstein, V. & Banerjee, U. A Hedgehog- and Antennapedia-dependent niche maintains Drosophila haematopoietic precursors. Nature 446, 320–324 (2007).
[PMID: 17361183]
Benmimoun, B., Polesello, C., Haenlin, M. & Waltzer, L. The EBF transcription factor Collier directly promotes Drosophila blood cell progenitor maintenance independently of the niche. Proc. Natl Acad. Sci. USA 112, 9052–9057 (2015).
[PMID: 26150488]
Grigorian, M., Mandal, L. & Hartenstein, V. Hematopoiesis at the onset of metamorphosis: terminal differentiation and dissociation of the Drosophila lymph gland. Dev. Genes Evol. 221, 121–131 (2011).
[PMID: 21509534]
Carton, Y. & Bouletreau, M. Encapsulation ability of Drosophila melanogaster: a genetic analysis. Dev. Comp. Immunol. 9, 211–219 (1985).
[PMID: 3926550]
Lemaitre, B. & Hoffmann, J. The host defense of Drosophila melanogaster. Annu. Rev. Immunol. 25, 697–743 (2007).
[PMID: 17201680]
Crozatier, M., Ubeda, J. M., Vincent, A. & Meister, M. Cellular immune response to parasitization in Drosophila requires the EBF orthologue collier. PLoS Biol. 2, E196 (2004).
[PMID: 15314643]
Sorrentino, R. P., Carton, Y. & Govind, S. Cellular immune response to parasite infection in the Drosophila lymph gland is developmentally regulated. Dev. Biol. 243, 65–80 (2002).
[PMID: 11846478]
Lanot, R., Zachary, D., Holder, F. & Meister, M. Postembryonic hematopoiesis in Drosophila. Dev. Biol. 230, 243–257 (2001).
[PMID: 11161576]
Macosko, E. Z. et al. Highly parallel genome-wide expression profiling of individual cells using nanoliter droplets. Cell 161, 1202–1214 (2015).
[PMID: 26000488]
Stuart, T. et al. Comprehensive integration of single-cell data. Cell 177, 1888–1902 e1821 (2019).
[PMID: 31178118]
Blondel, V. D., Guillaume, J.-L., Lambiotte, R. & Lefebvre, E. Fast unfolding of communities in large networks. J. Stat. Mech. 2008, P10008 (2008).
Hillyer, J. F., Schmidt, S. L. & Christensen, B. M. Hemocyte-mediated phagocytosis and melanization in the mosquito Armigeres subalbatus following immune challenge by bacteria. Cell Tissue Res. 313, 117–127 (2003).
[PMID: 12838409]
Severo, M. S. et al. Unbiased classification of mosquito blood cells by single-cell genomics and high-content imaging. Proc. Natl Acad. Sci. USA 115, E7568–E7577 (2018).
[PMID: 30038005]
Aibar, S. et al. SCENIC: single-cell regulatory network inference and clustering. Nat. Methods 14, 1083–1086 (2017).
[PMID: 28991892]
Hao, Y. & Jin, L. H. Dual role for Jumu in the control of hematopoietic progenitors in the Drosophila lymph gland. Elife 6, e25094 (2017).
Lebestky, T., Jung, S. H. & Banerjee, U. A Serrate-expressing signaling center controls Drosophila hematopoiesis. Genes Dev. 17, 348–353 (2003).
[PMID: 12569125]
Sadasivam, S. & DeCaprio, J. A. The DREAM complex: master coordinator of cell cycle-dependent gene expression. Nat. Rev. Cancer 13, 585–595 (2013).
[PMID: 23842645]
Evans, C. J., Liu, T. & Banerjee, U. Drosophila hematopoiesis: markers and methods for molecular genetic analysis. Methods 68, 242–251 (2014).
[PMID: 24613936]
Cao, J. et al. The single-cell transcriptional landscape of mammalian organogenesis. Nature 566, 496–502 (2019).
[PMID: 30787437]
Rommelaere, S., Boquete, J. P., Piton, J., Kondo, S. & Lemaitre, B. The exchangeable apolipoprotein Nplp2 sustains lipid flow and heat acclimation in Drosophila. Cell Rep. 27, 886–899 e886 (2019).
[PMID: 30995484]
Jang, Y. H., Chae, H. S. & Kim, Y. J. Female-specific myoinhibitory peptide neurons regulate mating receptivity in Drosophila melanogaster. Nat. Commun. 8, 1630 (2017).
[PMID: 29158481]
Ferguson, G. B. & Martinez-Agosto, J. A. Yorkie and scalloped signaling regulates notch-dependent lineage specification during Drosophila hematopoiesis. Curr. Biol. 24, 2665–2672 (2014).
[PMID: 25454586]
Tattikota, S. G. et al. A single-cell survey of Drosophila blood. Elife 9, e54818 (2020).
O’Flanagan, C. H. et al. Dissociation of solid tumor tissues with cold active protease for single-cell RNA-seq minimizes conserved collagenase-associated stress responses. Genome Biol. 20, 210 (2019).
[PMID: 31623682]
Owusu-Ansah, E. & Banerjee, U. Reactive oxygen species prime Drosophila haematopoietic progenitors for differentiation. Nature 461, 537–541 (2009).
[PMID: 19727075]
Shim, J. et al. Olfactory control of blood progenitor maintenance. Cell 155, 1141–1153 (2013).
[PMID: 24267893]
Moore, K. J., Sheedy, F. J. & Fisher, E. A. Macrophages in atherosclerosis: a dynamic balance. Nat. Rev. Immunol. 13, 709–721 (2013).
[PMID: 23995626]
Sharma, S. K., Ghosh, S., Geetha, A. R., Mandal, S. & Mandal, L. Cell adhesion-mediated actomyosin assembly regulates the activity of cubitus interruptus for hematopoietic progenitor maintenance in Drosophila. Genetics 212, 1279–1300 (2019).
[PMID: 31138608]
Baldeosingh, R., Gao, H., Wu, X. & Fossett, N. Hedgehog signaling from the posterior signaling center maintains U-shaped expression and a prohemocyte population in Drosophila. Dev. Biol. 441, 132–145 (2018).
[PMID: 29966604]
Ferguson, G. B. & Martinez-Agosto, J. A. The TEAD family transcription factor Scalloped regulates blood progenitor maintenance and proliferation in Drosophila through PDGF/VEGFR receptor (Pvr) signaling. Dev. Biol. 425, 21–32 (2017).
[PMID: 28322737]
Dey, N. S., Ramesh, P., Chugh, M., Mandal, S. & Mandal, L. Dpp dependent Hematopoietic stem cells give rise to Hh dependent blood progenitors in larval lymph gland of Drosophila. Elife 5, e18295 (2016).
Mondal, B. C. et al. Interaction between differentiating cell- and niche-derived signals in hematopoietic progenitor maintenance. Cell 147, 1589–1600 (2011).
[PMID: 22196733]
Minakhina, S. & Steward, R. Hematopoietic stem cells in Drosophila. Development 137, 27–31 (2010).
[PMID: 20023157]
Benmimoun, B., Polesello, C., Waltzer, L. & Haenlin, M. Dual role for Insulin/TOR signaling in the control of hematopoietic progenitor maintenance in Drosophila. Development 139, 1713–1717 (2012).
[PMID: 22510984]
Oyallon, J. et al. Two independent functions of collier/early B cell factor in the control of Drosophila blood cell homeostasis. PLoS ONE 11, e0148978 (2016).
[PMID: 26866694]
Sinenko, S. A. & Mathey-Prevot, B. Increased expression of Drosophila tetraspanin, Tsp68C, suppresses the abnormal proliferation of ytr-deficient and Ras/Raf-activated hemocytes. Oncogene 23, 9120–9128 (2004).
[PMID: 15480416]
Hombria, J. C., Brown, S., Hader, S. & Zeidler, M. P. Characterisation of Upd2, a Drosophila JAK/STAT pathway ligand. Dev. Biol. 288, 420–433 (2005).
[PMID: 16277982]
Avet-Rochex, A. et al. An in vivo RNA interference screen identifies gene networks controlling Drosophila melanogaster blood cell homeostasis. BMC Dev. Biol. 10, 65 (2010).
[PMID: 20540764]
He, L., Binari, R., Huang, J., Falo-Sanjuan, J. & Perrimon, N. In vivo study of gene expression with an enhanced dual-color fluorescent transcriptional timer. Elife 8, e46181 (2019).
Makhijani, K., Alexander, B., Tanaka, T., Rulifson, E. & Bruckner, K. The peripheral nervous system supports blood cell homing and survival in the Drosophila larva. Development 138, 5379–5391 (2011).
[PMID: 22071105]
Zhou, L. et al. Cooperative functions of the reaper and head involution defective genes in the programmed cell death of Drosophila central nervous system midline cells. Proc. Natl Acad. Sci. USA 94, 5131–5136 (1997).
[PMID: 9144202]
Evans, C. J. et al. G-TRACE: rapid Gal4-based cell lineage analysis in Drosophila. Nat. Methods 6, 603–605 (2009).
[PMID: 19633663]
Chell, J. M. & Brand, A. H. Nutrition-responsive glia control exit of neural stem cells from quiescence. Cell 143, 1161–1173 (2010).
[PMID: 21183078]
Couturier, L., Vodovar, N. & Schweisguth, F. Endocytosis by numb breaks notch symmetry at cytokinesis. Nat. Cell Biol. 14, 131–139 (2012).
[PMID: 22267085]
Zielke, N. et al. Fly-FUCCI: a versatile tool for studying cell proliferation in complex tissues. Cell Rep. 7, 588–598 (2014).
[PMID: 24726363]
Wolock, S. L., Lopez, R. & Klein, A. M. Scrublet: computational identification of cell doublets in single-cell transcriptomic data. Cell Syst. 8, 281–291 e289 (2019).
[PMID: 30954476]
van der Maaten, L. J. P. & Hinton, G. E. Visualizing high-dimensional data using t-SNE. J. Mach. Learn. Res. 9, 2579–2605 (2008).
Trapnell, C. et al. The dynamics and regulators of cell fate decisions are revealed by pseudotemporal ordering of single cells. Nat. Biotechnol. 32, 381–386 (2014).
[PMID: 24658644]
Kurucz, E. et al. Definition of Drosophila hemocyte subsets by cell-type specific antigens. Acta Biol. Hung. 58(Suppl), 95–111 (2007).
[PMID: 18297797]
Yoon, S. et al. Iron homeostasis controls myeloid blood cell differentiation in Drosophila. Mol. Cells 40, 976–985 (2017).
[PMID: 29237257]
Petraki, S., Alexander, B. & Bruckner, K. Assaying blood cell populations of the Drosophila melanogaster larva. J. Vis. Exp. 105, e52733 (2015).
Kishi, J. Y. et al. SABER amplifies FISH: enhanced multiplexed imaging of RNA and DNA in cells and tissues. Nat. Methods 16, 533–544 (2019).
[PMID: 31110282]