Macrophages (M ) play a central role as effector cells in immunity

The recognition of peptidoglycan by cells of the innate immune system has been controversial; both TLR2 and nucleotide-binding oligomerization domain-2 (NOD2) have been implicated in this process. In the present study we demonstrate that although NOD2 is required for recognition of peptidoglycan, this leads to strong synergistic effects on TLR2-mediated production of both pro- and anti-inflammatory cytokines. Defective IL-10 production in patients with Crohn’s disease bearing loss of function mutations of NOD2 may lead to overwhelming inflammation due to a subsequent Th1 bias. In addition to the potentiation of TLR2 effects, NOD2 is a modulator of signals transmitted through TLR4 and TLR3, but not through TLR5, TLR9, or TLR7. Thus, interaction between NOD2 and specific TLR pathways may represent an important modulatory mechanism of innate immune responses.

Objective: The aim of this study was to evaluate peak serum alanine aminotransferase (ALT) and postoperative clinical outcomes after hypothermic oxygenated machine perfusion (HOPE) versus static cold storage (SCS) in extended criteria donation (ECD) liver transplantation (LT) from donation after brain death (DBD). Background: HOPE might improve outcomes in LT, particularly in high-risk settings such as ECD organs after DBD, but this hypothesis has not yet been tested in a randomized controlled clinical trial (RCT). Methods: Between September 2017 and September 2020, 46 patients undergoing ECD-DBD LT from four centers were randomly assigned to HOPE (n = 23) or SCS (n = 23). Peak-ALT levels within 7 days following LT constituted the primary endpoint. Secondary endpoints included incidence of postoperative complications [Clavien-Dindo classification (CD), Comprehensive Complication Index (CCI)], length of intensive care- (ICU) and hospital-stay, and incidence of early allograft dysfunction (EAD). Results: Demographics were equally distributed between both groups [donor age: 72 (IQR: 59–78) years, recipient age: 62 (IQR: 55–65) years, labMELD: 15 (IQR: 9–25), 38 male and 8 female recipients]. HOPE resulted in a 47% decrease in serum peak ALT [418 (IQR: 221–828) vs 796 (IQR: 477–1195) IU/L, P = 0.030], a significant reduction in 90-day complications [44% vs 74% CD grade ≥3, P = 0.036; 32 (IQR: 12–56) vs 52 (IQR: 35–98) CCI, P = 0.021], and shorter ICU- and hospital-stays [5 (IQR: 4–8) vs 8 (IQR: 5–18) days, P = 0.045; 20 (IQR: 16–27) vs 36 (IQR: 23–62) days, P = 0.002] compared to SCS. A trend toward reduced EAD was observed for HOPE (17% vs 35%; P = 0.314). Conclusion: This multicenter RCT demonstrates that HOPE, in comparison to SCS, significantly reduces early allograft injury and improves post-transplant outcomes in ECD-DBD liver transplantation.

Dendritic cells (DC) are professional antigenpresenting cells of the immune system that play a key role in regulating T cell-based immunity. In vivo, the capacity of DC to activate T cells depends on their ability to migrate to the T cell areas of lymph nodes as well as on their maturation state. Depending on their cytokine-secreting proWle, DC are able to skew the immune response in a speciWc direction. In particular, IL-12p70 producing DC drive T cells towards a T helper 1 type response. A serious disadvantage of current clinical grade ex vivo generated monocyte-derived DC is the poor IL-12p70 production. We have investigated the eVects of Toll-like receptor (TLR)-mediated maturation on ex vivo generated human monocyte-derived DC. We demonstrate that in contrast to cytokine-matured DC, DC matured with poly(I:C) (TLR3 ligand) and/or R848 (TLR7/ 8 ligand) are able to produce vast amounts of IL-12p70, but exhibit a reduced migratory capacity. The addition of prostaglandin E 2 (PGE 2 ) improved the migratory capacity of TLR-ligand matured DC while maintaining their IL-12p70 production upon T cell encounter. We propose a novel clinical grade maturation protocol in which TLR ligands poly(I:C) and R848 are combined with PGE 2 to generate DC with both high migratory capacity and IL-12p70 production upon T cell encounter.