Activated macrophages promote hepatitis C virus entry in a tumor necrosis factor-dependent manner.

UNLABELLED: Macrophages are critical components of the innate immune response in the liver. Chronic hepatitis C is associated with immune infiltration and the infected liver shows a significant increase in total macrophage numbers; however, their role in the viral life cycle is poorly understood. Activation of blood-derived and intrahepatic macrophages with a panel of Toll-like receptor agonists induce soluble mediators that promote hepatitis C virus (HCV) entry into polarized hepatoma cells. We identified tumor necrosis factor α (TNF-α) as the major cytokine involved in this process. Importantly, this effect was not limited to HCV; TNF-α increased the permissivity of hepatoma cells to infection by Lassa, measles and vesicular stomatitis pseudoviruses. TNF-α induced a relocalization of tight junction protein occludin and increased the lateral diffusion speed of HCV receptor tetraspanin CD81 in polarized HepG2 cells, providing a mechanism for their increased permissivity to support HCV entry. High concentrations of HCV particles could stimulate macrophages to express TNF-α, providing a direct mechanism for the virus to promote infection. CONCLUSION: This study shows a new role for TNF-α to increase virus entry and highlights the potential for HCV to exploit existing innate immune responses in the liver to promote de novo infection events.

Non-enzymatic dissociation of human mesenchymal stromal cells improves chemokine-dependent migration and maintains immunosuppressive function.

BACKGROUND AIMS: Human bone marrow-derived mesenchymal stromal cells (MSC) can suppress inflammation; therefore their therapeutic potential is being explored in clinical trials. Poor engraftment of infused MSC limits their therapeutic utility; this may be caused by MSC processing before infusion, in particular the method of their detachment from culture. METHODS: Enzymatic methods of detaching MSC (Accutase and TrypLE) were compared with non-enzymatic methods (Cell Dissociation Buffer [CDB], ethylenediamine tetra-acetic acid and scraping) for their effect on MSC viability, chemokine receptor expression, multi-potency, immunomodulation and chemokine-dependent migration. RESULTS: TrypLE detachment preserved MSC viability and tri-lineage potential compared with non-enzymatic methods; however, this resulted in near complete loss of surface chemokine receptor expression. Of the non-enzymatic methods, CDB detachment preserved the highest viability while retaining significant tri-lineage differentiation potential. Once re-plated, CDB-detached MSC regained their original morphology and reached confluence, unlike with the use of other non-enzymatic methods. Viability was significantly reduced with the use of ethylenediamine tetra-acetic acid and further reduced with the use of cell scraping. Addition of 1% serum during CDB detachment led to higher MSC numbers entering autophagy and increased MSC recovery after re-plating. TrypLE and CDB-detached MSC suppressed CD3(+)CD4(+)CD25(-) T-cell proliferation, although TrypLE-detached MSC exhibited superior suppression at 1:20 ratio. CDB detachment retained surface chemokine receptor expression and consequently increased migration to CCL22, CXCL12 and CCL4, in contrast with TrypLE-detached MSC. CONCLUSIONS: This study demonstrates that non-enzymatic detachment of MSC with the use of CDB minimizes the negative impact on cell viability, multipotency and immunomodulation while retaining chemokine-dependent migration, which may be of importance in MSC delivery and engraftment in sites of injury.

Changing trends in thyroid and parathyroid surgery over the decade: is same-day discharge feasible in the United Kingdom?

BACKGROUND: A recent British Association of Endocrine and Thyroid Surgeons consensus document suggested that day-case thyroidectomy is feasible in a small proportion of patients but has to be balanced against risks. Currently, there is no large reported series of same-day discharge in thyroid and parathyroid surgery from the UK. The aim of this study was to assess the outcomes of day-case thyroid and parathyroid surgery. METHODS: We conducted a retrospective study of patients who underwent thyroid or parathyroid surgery between January 2000 and December 2011 at Oxford University Hospitals. The end points analysed were complications in the form of bleeding, hypocalcaemia, wound infection, and seroma. RESULTS: A total of 2,102 patients (495 males and 1,607 females, age range = 13-90 years) underwent surgery for parathyroid (n = 776) or thyroid (n = 1,326) conditions. The operations included minimally invasive parathyroidectomy (MIP) (n = 331), open parathyroidectomy (n = 445), lobectomy (n = 687), isthmusectomy (n = 23), total thyroidectomy (n = 580) and thyroglossal cyst excision (n = 36). Routine arrangements were in place for consideration of same-day discharge for lobectomies, thyroglossal cyst surgery, and MIPs; lobectomies accounted for 63 % of same-day cases, followed by parathyroidectomy (35 %). Over the decade, day-case surgery increased from 4 to 17 % for thyroid surgery and from 20 to 40 % for parathyroid surgery. None of the 435 patients who had same-day discharge was readmitted for bleeding [confidence interval (CI) 0-0.6 %]. There was no 30-day mortality for the whole cohort. Complications in patients who underwent surgery in the whole cohort versus those who were discharged the same day were temporary hypocalcaemia (4 vs. 0.2 %), permanent hypocalcaemia (1 vs. 0.4 %), bleeding (0.4 vs. 0 %), seroma (0.3 vs. 0 %), and wound infection (0.3 vs. 0 %). CONCLUSION: Current protocols for thyroid or parathyroid surgery make same-day discharge feasible and safe in carefully selected patients.

Single-centre experience of an early cannulation graft for haemodialysis access.

INTRODUCTION: As the demographics of the population changes, increasing challenges are being faced in providing reliable access for dialysis. This article reports on the outcomes from the largest series to date using the early cannulation graft Flixene in a single centre. METHODS: Between May 2012 and March 2018, 141 Flixene grafts were placed for dialysis access. The outcomes of the arteriovenous grafts were reviewed retrospectively from electronically held records and imaging. RESULTS: In 75 patients, placement of Flixene graft was performed on an emergency basis and in 66 patients on a planned elective list. The 12-month primary, assisted primary and secondary patency rates were 48.7%, 56.6% and 83.6%, respectively. Eight (5.7%) patients developed infections of the graft during the follow-up period. CONCLUSION: In our experience, we have found the use of the early cannulation graft Flixene to be safe with a low complication rate and favourable patency rates. We believe these early cannulation grafts provide a useful addition for vascular access surgeons preventing the use of tunnelled lines and providing more flexibility in the timing of placing a graft for dialysis.

Efforts to expand the donor pool for liver transplantation.

Liver transplantation has become a victim of its own success in that there are no longer enough suitable livers for transplantation while at the same time the indications for transplantation increase. Efforts to expand the number of recipients who benefit from this life-saving procedure are being made, in particular through the use of split grafts and live donors. However, such grafts are associated with increased morbidity and mortality related to their reduced size.