T cell deficiencies resulting from aberrant pre-mRNA alternative splicing caused by a novel splicing silencer hnRNP LL in an ENU mutant mouse strain thunder

ENU mutagenesis screening is a phenotype-driven approach to identify genes in a nonbiased manner. Through this approach we identified a previously uncharacterised gene, Hnrpll, which is involved in nascent mRNA alternative splicing. Thunder strain carries a point mutation in the Hnrpll gene (407T->A) in its first RNA recognition motif (RRM) which changes it function in regulating nascent mRNA alternative splicing. One of Hnrpll target genes is CD45 that undergoes alternative splicing in T cells depending on their development stages and activation status. We demonstrated that Hnrpllthu/thu T cells fail to silence 3 variable exons of CD45 and result in constitutive expression of CD45RA, B, and C epitopes on the cell surface. Retroviral based expression of wild-type Hnrpll cDNA in the Hnrpllthu/thu T cells compensates the effects of loss of function in the mutation. The mutated RRM1 domain remains the ability to bind the regulatory element of activation responsive sequence (ARS) within CD45 pre-mRNA but cripples the protein function by destabilising the proteins to unfold in a thermolible sensitive manner. We also found that Hnrpllthu/thu mutation disrupts peripheral T cell subsets. Thunder mice have normal T cell development in the thymus but specifically lost naïve T cells in the peripheral lymphoid tissues, whereas memory T cells are not affected. Hnrpllthu/thu naïve T cells can homeostatically proliferate but fail to persist for a long term in vivo, suggesting that thunder mutation influences naïve T cell longevity. We observed that Hnrpllthu/thu naïve T cells express lower level of IL-7Ra and lower Bcl-2, together with the stronger pro-apoptotic BimS isoform due to alternative splicing. This highlights the nonredundant role of the Hnrpll gene in regulating peripheral T cell homeostasis. CD45 isoforms are widely used markers to distinguish naïve and memory T cell subsets. CD45 splicing does not account for the loss of naïve T cells in the thunder mice, however, CD45RABC shows stronger phosphatase activity than CD45RO when the amount of CD45 is dramatically reduced to 5% remaining on T cell surface, suggesting jointly regulation of CD45 catalytic activity by its expression and alternative splicing. Immunological memory is the hallmark of the adaptive immune system. Through Affymetrix mouse all exon arrays, we found that hnRNP LL protein plays a critical role in controlling an extensive program of alternative splicing as naïve T cells differentiate to the memory cell fate. It acts as an either trans- or cis- acting factor in regulating multiple nascent mRNA alternative splicing. This study provides an unprecedented insight into the extent of alternative splicing in the generation of immune memory

A Unified Health Information System Framework for Connecting Data, People, Devices, and Systems

The COVID-19 pandemic has heightened the necessity for pervasive data and system interoperability to manage healthcare information and knowledge. There is an urgent need to better understand the role of interoperability in improving the societal responses to the pandemic. This paper explores data and system interoperability, a very specific area that could contribute to fighting COVID-19. Specifically, the authors propose a unified health information system framework to connect data, systems, and devices to increase interoperability and manage healthcare information and knowledge. A blockchain-based solution is also provided as a recommendation for improving the data and system interoperability in healthcare

Consequences of increased CD45RA and RC isoforms for TCR signaling and peripheral T cell deficiency resulting from heterogeneous nuclear ribonucleoprotein L-like mutation

CD45 is the most abundant protein tyrosine phosphatase in the plasma membrane of T cells and serves a critical role in TCR signaling. Different CD45 isoforms are made by alternative mRNA splicing depending on the stage of T cell development and activation, yet their role remains unclear. Expression of CD45RA and RC isoforms is increased 20- to 200-fold on T cells from thunder mice with a loss-of-function mutation in the RNA-binding protein, heterogeneous nuclear ribonucleoprotein L-like (hnRNPLL), although total CD45 expression is unaltered. In this study, we test the hypothesis that this shift in CD45 isoform expression alters TCR signaling, thymic selection, and accumulation of peripheral T cells. There was no discernable effect of the change in CD45 isoform expression upon Lck phosphorylation or T cell positive and negative selection, whereas these indices were strongly affected by a decrease in the overall amount of CD45 in Ptprc mutant animals. The one exception to this conclusion was in thymocytes from Ptprcloc/loc animals with 4% of normal CD45 protein levels, where Lck505 phosphorylation was increased 25% in Hnrpll mutant cells, suggesting that high m.w. CD45 isoforms had lower Lck505 phosphatase activity in this context. In T cells with no CD45 protein, hnRNPLL mutation still diminished peripheral T cell accumulation, demonstrating that hnRNPLL regulates T cell longevity independently from its effects on CD45 splicing

Heparanase and autoimmune diabetes

Heparanase (Hpse) is the only known mammalian endo-β-d-glucuronidase that degrades the glycosaminoglycan heparan sulfate (HS), found attached to the core proteins of heparan sulfate proteoglycans (HSPGs). Hpse plays a homeostatic role in regulating the turnover of cell-associated HS and also degrades extracellular HS in basement membranes (BMs) and the extracellular matrix (ECM), where HSPGs function as a barrier to cell migration. Secreted Hpse is harnessed by leukocytes to facilitate their migration from the blood to sites of inflammation. In the non-obese diabetic (NOD) model of autoimmune Type 1 diabetes (T1D), Hpse is also used by insulitis leukocytes to solubilize the islet BM to enable intra-islet entry of leukocytes and to degrade intracellular HS, an essential component for the survival of insulin-producing islet beta cells. Treatment of pre-diabetic adult NOD mice with the Hpse inhibitor PI-88 significantly reduced the incidence of T1D by ~50% and preserved islet HS. Hpse therefore acts as a novel immune effector mechanism in T1D. Our studies have identified T1D as a Hpse-dependent disease and Hpse inhibitors as novel therapeutics for preventing T1D progression and possibly the development of T1D vascular complications.This work was supported by a National Health and Medical Research Council of Australia (NHMRC)/Juvenile Diabetes Research Foundation (JDRF) Special Program Grant in Type 1 Diabetes (#418138), a NHMRC Project Grant (#1043284), and a research grant from the Roche Organ Transplantation Research Foundation (ROTRF)/JDRF (#477554991)

Heterogeneity of Human Neutrophil CD177 Expression Results from CD177P1 Pseudogene Conversion

Most humans harbor both CD177neg and CD177pos neutrophils but 1–10% of people are CD177null, placing them at risk for formation of anti-neutrophil antibodies that can cause transfusion-related acute lung injury and neonatal alloimmune neutropenia. By deep sequencing the CD177 locus, we catalogued CD177 single nucleotide variants and identified a novel stop codon in CD177null individuals arising from a single base substitution in exon 7. This is not a mutation in CD177 itself, rather the CD177null phenotype arises when exon 7 of CD177 is supplied entirely by the CD177 pseudogene (CD177P1), which appears to have resulted from allelic gene conversion. In CD177 expressing individuals the CD177 locus contains both CD177P1 and CD177 sequences. The proportion of CD177hi neutrophils in the blood is a heritable trait. Abundance of CD177hi neutrophils correlates with homozygosity for CD177 reference allele, while heterozygosity for ectopic CD177P1 gene conversion correlates with increased CD177neg neutrophils, in which both CD177P1 partially incorporated allele and paired intact CD177 allele are transcribed. Human neutrophil heterogeneity for CD177 expression arises by ectopic allelic conversion. Resolution of the genetic basis of CD177null phenotype identifies a method for screening for individuals at risk of CD177 isoimmunisation

Heterogeneity of human Neutrophil CD177 expression results from CD177P1 Pseudogene Conversion

Most humans harbor both CD177neg and CD177pos neutrophils but 1–10% of people are CD177null, placing them at risk for formation of anti-neutrophil antibodies that can cause transfusion-related acute lung injury and neonatal alloimmune neutropenia. By deep sequencing the CD177 locus, we catalogued CD177 single nucleotide variants and identified a novel stop codon in CD177null individuals arising from a single base substitution in exon 7. This is not a mutation in CD177 itself, rather the CD177null phenotype arises when exon 7 of CD177 is supplied entirely by the CD177 pseudogene (CD177P1), which appears to have resulted from allelic gene conversion. In CD177 expressing individuals the CD177 locus contains both CD177P1 and CD177 sequences. The proportion of CD177hi neutrophils in the blood is a heritable trait. Abundance of CD177hi neutrophils correlates with homozygosity for CD177 reference allele, while heterozygosity for ectopic CD177P1 gene conversion correlates with increased CD177neg neutrophils, in which both CD177P1 partially incorporated allele and paired intact CD177 allele are transcribed. Human neutrophil heterogeneity for CD177 expression arises by ectopic allelic conversion. Resolution of the genetic basis of CD177null phenotype identifies a method for screening for individuals at risk of CD177 isoimmunisation

The socio-spatial design of community and governance: Interdisciplinary urban design in China

This book proposes a new interdisciplinary understanding of urban design in China based on a study of the transformative effects of socio-spatial design and planning on communities and their governance. This is framed by an examination of the social projects, spaces, and realities that have shaped three contexts critical to the understanding of urban design problems in China: the histories of “collective forms” and “collective spaces”, such as that of the urban danwei (work-unit), which inform current community building and planning; socio-spatial changes in urban and rural development; and disparate practices of “spatialised governmentality”. These contexts and an attendant transformation from planning to design and from government to governance, define the current urban design challenges found in the dominant urban xiaoqu (small district) and shequ (community) development model. Examining the histories, transformations, and practices that have shaped socio-spatial epistemologies and experiences in China – including a specific sense of community and place that is rather based on a concrete “collective” than abstract “public” space and underpinned by socialised governance – this book brings together a diverse range of observations, thoughts, analyses, and projects by urban researchers and practitioners. Thereby discussing emerging interdisciplinary urban design practices in China, this book offers a valuable resource for all academics, practitioners, and stakeholders with an interest in socio-spatial design and development

Information technology solutions, challenges, and suggestions for tackling the COVID-19 pandemic

Various technology innovations and applications have been developed to fight the coronavirus pandemic. The pandemic also has implications for the design, development, and use of technologies. There is an urgent need for a greater understanding of what roles information systems and technology researchers can play in this global pandemic. This paper examines emerging technologies used to mitigate the threats of COVID-19 and relevant challenges related to technology design, development, and use. It also provides insights and suggestions into how information systems and technology scholars can help fight the COVID-19 pandemic. This paper helps promote future research and technology development to produce better solutions for tackling the COVID-19 pandemic and future pandemics

Blockchain adoption for information sharing: risk decision-making in spacecraft supply chain

This research studies the risk decision-making (RDM) problem faced by participants in a spacecraft supply chain, considering the adoption of the blockchain technology to facilitate information sharing. We investigate a three-level spacecraft supply chain composed of a spacecraft builder, supplier, and logistics service integrator with the Stackelberg game under the scenarios of decentralized, partially centralized, and fully centralized decision-making. For each scenario, we show how the spacecraft builder’s optimal order quantity and the supplier’s application degree of the blockchain technology change with the spacecraft builder’s risk coefficient. We also compare the overall profit of the supply chain for three decision-making scenarios