Larvae expressing Hsap\HOXA9::Hsap\NUP98WT.UAS under the control of Scer\GAL4Hml.Δ show a fully penetrant lymph gland enlargement, where most individuals show dispersion of the primary lobe accompanied by enlargement of the secondary lobe and a few individuals showing primary lobe enlargement, as compared to controls. These larval lymph glands show increased mitotic index (phospho-H3 staining) and a severe increase in the numbers of Hml-positive lymph gland cells; this correlates with a severe increase in the number of Hml-positive circulating hemocytes, which show a similar ability to phagocyte E.coli and S.aureus as controls, although the proportion of circulating P1-positive hemocytes seems decreased. The medullary zone of non-dispersed lymph glands is smaller than controls, but there are no apparent changes in terminal differentiation into plasmocytes (P1-positive cells) or crystal cells (Hnt-positive cells), as compared to controls. The posterior signalling center is larger, with more total and mitotic cells, as compared to controls.
Depending on the Hsap\HOXA9::Hsap\NUP98WT.UAS insertion (and corresponding inducible expression levels), Scer\GAL4Hml.Δ-driven expression induces lamellocyte differentiation in the lymph gland.
Expression under the control of Scer\GAL4Pxn.PS also results in an enlarged larval lymph gland, with a severely enlarged and misshapen posterior signalling center. Expression under the control of Scer\GAL4kn-col85-GAL4 also induces a severely enlarged posterior signalling center.
Expression under the control of either Scer\GAL4ey.PH or Scer\GAL4Bx-MS1096 does not induce overgrowth in the eye disc or wing disc, respectively.