Type 1 and type 2 cytokine-mediated immune orchestration in the tumour microenvironment and their therapeutic potential

Cancer remains the second leading cause of death worldwide despite modern breakthroughs in medicine, and novel treatments are urgently needed. The revolutionary success of immune checkpoint inhibitors in the past decade serves as proof of concept that the immune system can be effectively harnessed to treat cancer. Cytokines are small signalling proteins with critical roles in orchestrating the immune response and have become an attractive target for immunotherapy. Type 1 immune cytokines, including interferon γ (IFNγ), interleukin-12 (IL-12), and tumour necrosis factor α (TNFα), have been shown to have largely tumour suppressive roles in part through orchestrating anti-tumour immune responses mediated by natural killer (NK) cells, CD8+ T cells and T helper 1 (Th1) cells. Conversely, type 2 immunity involving group 2 innate lymphoid cells (ILC2s) and Th2 cells are involved in tissue regeneration and wound repair and are traditionally thought to have pro-tumoural effects. However, it is found that the classical type 2 immune cytokines IL-4, IL-5, IL-9, and IL-13 may have conflicting roles in cancer. Similarly, type 2 immunity-related cytokines IL-25 and IL-33 with recently characterised roles in cancer may either promote or suppress tumorigenesis in a context-dependent manner. Furthermore, type 1 cytokines IFNγ and TNFα have also been found to have pro-tumoural effects under certain circumstances, further complicating the overall picture. Therefore, the dichotomy of type 1 and type 2 cytokines inhibiting and promoting tumours respectively is not concrete, and attempts of utilising these for cancer immunotherapy must take into account all available evidence. This review provides an overview summarising the current understanding of type 1 and type 2 cytokines in tumour immunity and discusses the prospects of harnessing these for immunotherapy in light of previous and ongoing clinical trials

Why are the Trial-By-Trial, Strength-Based Criterion Shifts Hard to Observe? Is the Difficulty in the Mental Process Itself or in the Typical Cued-Criterion Method?

In the cued-criterion recognition paradigm (Stretch & Wixted, 1998a), trial-by-trial memory-strength based criterion shifts have been an elusive phenomenon. Often the criterion shifts fail to occur. We suggest that the frequent failure in making criterion shifts in the literature is due to participants’ failure to understand the rationale of the task as typically presented in an abstract format. In this study, participants studied words once or thrice and were asked at test to either classify the probes into “new”, “seen once”, or “seen 3 times” categories by pressing the corresponding keys, or to make an Old/New binary decision followed by an item presentation-frequency judgment, a confidence, or a memory-quality judgment. No memory-strength cues were provided and only one set of new items served as distractors for strong and weak targets. Robust trial-by-trial criterion shift was observed. We concluded that no cues distinguishing between strong and weak probes are necessary for obtaining this type of criterion shift when the tasks are designed to make good pragmatic sense for the participants. The reason why this type of criterion shifts is typically hard to obtain in the cued-criterion paradigm is not that the process itself is difficult, but that the cued-criterion method is hard to understand to the participants

A retrospective analysis of the definitive management of open talus fractures at a major trauma centre, comparing ORIF to FUSION: cohort study and audit of BOAST 4 guidelines.

PURPOSE: Open talus fractures are notoriously difficult to manage, and they are commonly associated with a high level of complications including non-union, avascular necrosis and infection. Currently, the management of such injuries is based upon BOAST 4 guidelines although there is no suggested definitive management, and thus, definitive management is based upon surgeon preference. The key principles of open talus fracture management which do not vary between surgeons are early debridement, orthoplastic wound care, anatomic reduction and definitive fixation whenever possible. However, there is much debate over whether the talus should be preserved or removed after open talus fracture/dislocation and proceeded to tibiocalcaneal fusion. METHODS: A review of electronic hospital records for open talus fractures from 2014 to 2021 returned fourteen patients with fifteen open talus fractures. Seven cases were initially managed with ORIF, and five cases were definitively managed with FUSION, while the others were managed with alternative methods. We collected patient's age, gender, surgical complications, surgical risk factors and post-treatment functional ability and pain and compliance with BOAST guidelines. The average follow-up of the cohort was 4 years and one month. EQ-5D-5L and FAAM-ADL/Sports score was used as a patient reported outcome measure. Data were analysed using the software PRISM. RESULTS: Comparison between FUSION and ORIF groups showed no statistically significant difference in EQ-5D-5L score (P = 0.13), FAAM-ADL (P = 0.20), FAAM-Sport (P = 0.34), infection rate (P = 0.55), surgical times (P = 0.91) and time to weight bearing (P = 0.39), despite a higher proportion of polytrauma and Hawkins III and IV fractures in the FUSION group. CONCLUSION: FUSION is typically used as second line to ORIF or failed ORIF. However, there is a lack of studies that directly compared outcome in open talus fracture patients definitively managed with FUSION or ORIF. Our results demonstrate for the first time that FUSION may not be inferior to ORIF in terms of patient functional outcome, infection rate and quality of life, in the management of patients with open talus fracture patients. Of note, as open talus fractures have increased risks of complications such as osteonecrosis and non-union, FUSION should be considered as a viable option to mitigate these potential complications in these patients

Esophageal Clearance Patterns in Normal Older Adults as Documented with Videofluoroscopic Esophagram

Normal esophageal bolus transport in asymptomatic healthy older adults has not been well defined, potentially leading to ambiguity in differentiating esophageal swallowing patterns of dysphagic and healthy individuals. This pilot study of 24 young (45–64 years) and old (65+years) men and women was designed to assess radiographic esophageal bolus movement patterns in healthy adults using videofluoroscopic recording. Healthy, asymptomatic adults underwent videofluoroscopic esophagram to evaluate for the presence of ineffective esophageal clearance, namely, intraesophageal stasis and intraesophageal reflux. Intraesophageal stasis and intraesophageal reflux were visualized radiographically in these normal subjects. Intraesophageal stasis occurred significantly more frequently with semisolid (96%) compared with liquid (16%) barium, suggesting that a variety of barium consistencies, as opposed to only the traditional fluids, would better define the spectrum of esophageal transport. Intraesophageal reflux was observed more frequently in older males than in their younger counterparts. The rates of intraesophageal stasis and intraesophageal reflux were potentially high given that successive bolus presentations were spaced 10 seconds apart. These findings suggest a need for a more comprehensive definition regarding the range of normal esophageal bolus transport to (a) prevent misdiagnosis of dysphagia and (b) to enhance generalization to functional eating, which involves solid foods in addition to liquids

Thermomechanical Response of a Representative Porin for Biomimetics

The thermomechanical response of Omp2a, a representative porin used for the fabrication of smart biomimetic nanomembranes, has been characterized using microcantilever technology and compared with standard proteins. For this purpose, thermally induced transitions involving the conversion of stable trimers to bigger aggregates, local reorganizations based on the strengthening or weakening of intermolecular interactions, and protein denaturation have been detected by the microcantilever resonance frequency and deflection as a function of the temperature. Measurements have been carried out on arrays of 8-microcantilevers functionalized with proteins (Omp2a, lysozyme and bovine serum albumin). To interpret the measured nanofeatures, the response of proteins to temperature has been also examined using other characterization techniques, including real time wide angle X-ray diffraction. Results not only demonstrate the complex behavior of porins, which exhibit multiple local thermal transitions before undergoing denaturation at temperatures higher than 105 °C, but also suggest a posttreatment to control the orientation of immobilized Omp2a molecules in functionalized biomimetic nanomembranes and, thus, increase their efficacy in ion transport.Peer Reviewe

Properties of Omp2a-based supported lipid bilayers: comparison with polymeric bioinspired membranes

Omp2a ß-barrel outer membrane protein has been reconstituted into supported lipid bilayers (SLBs) to compare the nanomechanical properties (elastic modulus, adhesion forces, and deformation) and functionality of the resulting bioinspired system with those of Omp2a-based polymeric nanomembranes (NMs). Protein reconstitution into lipid bilayers has been performed using different strategies, the most successful one consisting of a detergent-mediated process into preformed liposomes. The elastic modulus obtained for the lipid bilayer and Omp2a are ~19 and 10.5 ± 1.7 MPa, respectively. Accordingly, the protein is softer than the lipid bilayer, whereas the latter exhibits less mechanical strength than polymeric NMs. Besides, the function of Omp2a in the SLB is similar to that observed for Omp2a-based polymeric NMs. Results open the door to hybrid bioinspired substrates based on the integration of Omp2a-proteoliposomes and nanoperforated polymeric freestanding NMs.Peer ReviewedPostprint (author's final draft

Transduction of rat pancreatic islets with pseudotyped adeno-associated virus vectors

<p>Abstract</p> <p>Background</p> <p>Pancreatic islet transplantation is a promising treatment for type I diabetes mellitus, but current immunosuppressive strategies do not consistently provide long-term survival of transplanted islets. We are therefore investigating the use of adeno-associated viruses (AAVs) as gene therapy vectors to transduce rat islets with immunosuppressive genes prior to transplantation into diabetic mice.</p> <p>Results</p> <p>We compared the transduction efficiency of AAV2 vectors with an AAV2 capsid (AAV2/2) to AAV2 vectors pseudotyped with AAV5 (AAV2/5), AAV8 (AAV2/8) or bovine adeno-associated virus (BAAV) capsids, or an AAV2 capsid with an insertion of the low density lipoprotein receptor ligand from apolipoprotein E (AAV2apoE), on cultured islets, in the presence of helper adenovirus infection to speed expression of a GFP transgene. Confocal microscopy and flow cytometry were used. The AAV2/5 vector was superior to AAV2/2 and AAV2/8 in rat islets. Flow cytometry indicated AAV2/5-mediated gene expression in approximately 9% of rat islet cells and almost 12% of insulin-positive cells. The AAV2/8 vector had a higher dependence on the helper virus multiplicity of infection than the AAV 2/5 vector. In addition, the BAAV and AAV2apoE vectors were superior to AAV2/2 for transducing rat islets. Rat islets (300 per mouse) transduced with an AAV2/5 vector harboring the immunosuppressive transgene, <it>tgfβ1</it>, retain the ability to correct hyperglycemia when transplanted into immune-deficient diabetic mice.</p> <p>Conclusion</p> <p>AAV2/5 vectors may therefore be useful for pre-treating donor islets prior to transplantation.</p

Using pre-clinical studies to explore the potential clinical uses of exosomes secreted from induced pluripotent stem cell-derived mesenchymal stem cells

Recent studies of exosomes derived from mesenchymal stem cells (MSCs) have indicated high potential clinical applications in many diseases. However, the limited source of MSCs impedes their clinical research and application. Most recently, induced pluripotent stem cells (iPSCs) have become a promising source of MSCs. Exosome therapy based on iPSC-derived MSCs (iMSCs) is a novel technique with much of its therapeutic potential untapped. Compared to MSCs, iMSCs have proved superior in cell proliferation, immunomodulation, generation of exosomes capable of controlling the microenvironment, and bioactive paracrine factor secretion, while also theoretically eliminating the dependence on immunosuppression drugs. The therapeutic effects of iMSC-derived exosomes are explored in many diseases and are best studied in wound healing, cardiovascular disease, and musculoskeletal pathology. It is pertinent clinicians have a strong understanding of stem cell therapy and the latest advances that will eventually translate into clinical practice. In this review, we discuss the various applications of exosomes derived from iMSCs in clinical medicine

A stromal cell niche sustains ILC2-mediated type-2 conditioning in adipose tissue.

Group-2 innate lymphoid cells (ILC2), type-2 cytokines, and eosinophils have all been implicated in sustaining adipose tissue homeostasis. However, the interplay between the stroma and adipose-resident immune cells is less well understood. We identify that white adipose tissue-resident multipotent stromal cells (WAT-MSCs) can act as a reservoir for IL-33, especially after cell stress, but also provide additional signals for sustaining ILC2. Indeed, we demonstrate that WAT-MSCs also support ICAM-1-mediated proliferation and activation of LFA-1-expressing ILC2s. Consequently, ILC2-derived IL-4 and IL-13 feed back to induce eotaxin secretion from WAT-MSCs, supporting eosinophil recruitment. Thus, MSCs provide a niche for multifaceted dialogue with ILC2 to sustain a type-2 immune environment in WAT