• Experimental long-term diabetes mellitus alters the transcriptome and biomechanical properties of the rat urinary bladder

      Hindi, Emad A.; Williams, Craig J.; Zeef, Leo A. H.; Lopes, Filipa M.; Newman, Katie; Davey, Martha M. M.; Hodson, Nigel W.; Hilton, Emma N.; Huang, Jennifer L.; Price, Karen L.; et al. (Nature Publishing Group UK, 2021-07-30)
      Abstract: Diabetes mellitus (DM) is the leading cause of chronic kidney disease and diabetic nephropathy is widely studied. In contrast, the pathobiology of diabetic urinary bladder disease is less understood despite dysfunctional voiding being common in DM. We hypothesised that diabetic cystopathy has a characteristic molecular signature. We therefore studied bladders of hyperglycaemic and polyuric rats with streptozotocin (STZ)-induced DM. Sixteen weeks after induction of DM, as assessed by RNA arrays, wide-ranging changes of gene expression occurred in DM bladders over and above those induced in bladders of non-hyperglycaemic rats with sucrose-induced polyuria. The altered transcripts included those coding for extracellular matrix regulators and neural molecules. Changes in key genes deregulated in DM rat bladders were also detected in db/db mouse bladders. In DM rat bladders there was reduced birefringent collagen between detrusor muscle bundles, and atomic force microscopy showed a significant reduction in tissue stiffness; neither change was found in bladders of sucrose-treated rats. Thus, altered extracellular matrix with reduced tissue rigidity may contribute to voiding dysfunction in people with long-term DM. These results serve as an informative stepping stone towards understanding the complex pathobiology of diabetic cystopathy.
    • Experimental long-term diabetes mellitus alters the transcriptome and biomechanical properties of the rat urinary bladder

      Hindi, Emad A.; Williams, Craig J.; Zeef, Leo A. H.; Lopes, Filipa M.; Newman, Katie; Davey, Martha M. M.; Hodson, Nigel W.; Hilton, Emma N.; Huang, Jennifer L.; Price, Karen L.; et al. (Nature Publishing Group UK, 2021-07-30)
      Abstract: Diabetes mellitus (DM) is the leading cause of chronic kidney disease and diabetic nephropathy is widely studied. In contrast, the pathobiology of diabetic urinary bladder disease is less understood despite dysfunctional voiding being common in DM. We hypothesised that diabetic cystopathy has a characteristic molecular signature. We therefore studied bladders of hyperglycaemic and polyuric rats with streptozotocin (STZ)-induced DM. Sixteen weeks after induction of DM, as assessed by RNA arrays, wide-ranging changes of gene expression occurred in DM bladders over and above those induced in bladders of non-hyperglycaemic rats with sucrose-induced polyuria. The altered transcripts included those coding for extracellular matrix regulators and neural molecules. Changes in key genes deregulated in DM rat bladders were also detected in db/db mouse bladders. In DM rat bladders there was reduced birefringent collagen between detrusor muscle bundles, and atomic force microscopy showed a significant reduction in tissue stiffness; neither change was found in bladders of sucrose-treated rats. Thus, altered extracellular matrix with reduced tissue rigidity may contribute to voiding dysfunction in people with long-term DM. These results serve as an informative stepping stone towards understanding the complex pathobiology of diabetic cystopathy.
    • Memory CD8 + T cells exhibit tissue imprinting and non‐stable exposure‐dependent reactivation characteristics following blood‐stage Plasmodium berghei ANKA infections

      Shaw, Tovah N.; Haley, Michael J.; Dookie, Rebecca S.; Godfrey, Jenna J.; Cheeseman, Antonn J.; Strangward, Patrick; Zeef, Leo A. H.; Villegas‐Mendez, Ana; Couper, Kevin N.; orcid: 0000-0003-4659-8960; email: kevin.couper@manchester.ac.uk (2021-08-27)
      Abstract: Experimental cerebral malaria (ECM) is a severe complication of Plasmodium berghei ANKA (PbA) infection in mice, characterized by CD8+ T‐cell accumulation within the brain. Whilst the dynamics of CD8+ T‐cell activation and migration during extant primary PbA infection have been extensively researched, the fate of the parasite‐specific CD8+ T cells upon resolution of ECM is not understood. In this study, we show that memory OT‐I cells persist systemically within the spleen, lung and brain following recovery from ECM after primary PbA‐OVA infection. Whereas memory OT‐I cells within the spleen and lung exhibited canonical central memory (Tcm) and effector memory (Tem) phenotypes, respectively, memory OT‐I cells within the brain post‐PbA‐OVA infection displayed an enriched CD69+CD103− profile and expressed low levels of T‐bet. OT‐I cells within the brain were excluded from short‐term intravascular antibody labelling but were targeted effectively by longer‐term systemically administered antibodies. Thus, the memory OT‐I cells were extravascular within the brain post‐ECM but were potentially not resident memory cells. Importantly, whilst memory OT‐I cells exhibited strong reactivation during secondary PbA‐OVA infection, preventing activation of new primary effector T cells, they had dampened reactivation during a fourth PbA‐OVA infection. Overall, our results demonstrate that memory CD8+ T cells are systemically distributed but exhibit a unique phenotype within the brain post‐ECM, and that their reactivation characteristics are shaped by infection history. Our results raise important questions regarding the role of distinct memory CD8+ T‐cell populations within the brain and other tissues during repeat Plasmodium infections.