Hepatocellular carcinoma after direct-acting antivirals for hepatitis C is associated with KIR-HLA types predicting weak NK cell-mediated immunity.

BACKGROUND AND AIMS: Second-generation direct-acting antivirals (2G DAA) to cure HCV have led to dramatic clinical improvements. HCV-associated hepatocellular carcinoma (HCC), however, remains common. Impaired immune tumor surveillance may play a role in HCC development. Our cohort evaluated the effects of innate immune types and clinical variables on outcomes including HCC. METHODS: Participants underwent full HLA class I/KIR typing and long-term HCV follow-up. RESULTS: A total of 353 HCV+ participants were followed for a mean of 7 years. Cirrhosis: 25% at baseline, developed in 12% during follow-up. 158 participants received 2G DAA therapy. HCC developed without HCV therapy in 20 subjects, 24 HCC after HCV therapy, and 10 of these after 2G DAA. Two predictors of HCC among 2G DAA-treated patients: cirrhosis (OR, 10.0, p = 0.002) and HLA/KIR profiles predicting weak natural killer (NK) cell-mediated immunity (NK cell complementation groups 6, 9, 11, 12, OR of 5.1, p = 0.02). Without 2G DAA therapy: cirrhosis was the main clinical predictor of HCC (OR, 30.8, p < 0.0001), and weak NK-cell-mediated immunity did not predict HCC. CONCLUSION: Cirrhosis is the main risk state predisposing to HCC, but weak NK-cell-mediated immunity may predispose to post-2G DAA HCC more than intermediate or strong NK-cell-mediated immunity.

Skin closure with surgical staples in ankle fractures: a safe and reliable method.

PURPOSE: The purpose of this study is to examine the rates of surgical site complications of staple closure versus suture closure following open reduction and internal fixation of closed unstable ankle fractures. METHODS: Between 2014 and 2016, a total of 545 patients with closed ankle fractures were treated at our level-1 trauma centre by means of open reduction and internal fixation. A total of 360 patients matched the inclusion criteria and were included in the final analysis of this study. This included 119 patients undergoing wound closure using sutures and 241 patients using surgical staples. The demographics, clinical data, and injury characteristics were recorded. The primary outcome measure was the adverse event of any type of surgical site complication. RESULTS: The overall rate of patients with a surgical site complication was 15.6%. There was a trend towards a higher risk of surgical site complication in patients undergoing wound closure with sutures as compared with staples (20.2% versus 13.3%); however, this difference was not statistically significant (P = 0.0897). The rate of superficial surgical site infection also trended higher in patients undergoing wound closure with sutures versus staples without demonstrating statistical significance (10.1% versus 5%, P = 0.0678). The rate of deep surgical site infection was similar in both groups. CONCLUSION: The use of metal staples remains controversial in the setting of orthopedic surgery, particularly involving the foot and ankle. The current study supports that metal staples are a safe and reliable option in the closure of traumatic ankle fractures.

Identification of MHC Class Ib Ligands for Stimulatory and Inhibitory Ly49 Receptors and Induction of Potent NK Cell Alloresponses in Rats.

Early studies indicate that rats may have a repertoire of MHC class Ib-reactive Ly49 stimulatory receptors capable of mounting memory-like NK cell alloresponses. In this article, we provide molecular and functional evidence for this assumption. Pairs of Ly49 receptors with sequence similarities in the lectin-like domains, but with opposing signaling functions, showed specificity for ligands with class Ia-like structural features encoded from the first telomeric MHC class Ib gene cluster, RT1-CE, which is syntenic with the H2-D/H2-L/H2-Q cluster in mice. The activating Ly49s4 receptor and its inhibitory counterparts, Ly49i4 and Ly49i3, reacted with all allelic variants of RT1-U, whereas Ly49s5 and Ly49i5 were specific for RT1-Eu NK cell cytolytic responses were predictably activated and inhibited, and potent in vivo NK alloresponses were induced by repeated MHC class Ib alloimmunizations. Additional Ly49-class Ib interactions, including RT1-Cl with the Ly49s4/Ly49i4/Ly49i3 group of receptors, were characterized using overexpressed receptor/ligand pairs, in vitro functional assays, and limited mutational analyses. Obvious, as well as subtle, Ly49-class Ib interactions led to ligand-induced receptor calibration and NK subset expansions in vivo. Together, these studies suggest that in vivo NK alloresponses are controlled by pleomorphic Ly49-class Ib interactions, some of which may not be easily detectable in vitro.

Memory T Cell Proliferation before Hepatitis C Virus Therapy Predicts Antiviral Immune Responses and Treatment Success.

The contribution of the host immune system to the efficacy of new anti-hepatitis C virus (HCV) drugs is unclear. We undertook a longitudinal prospective study of 33 individuals with chronic HCV treated with combination pegylated IFN-α, ribavirin, and telaprevir/boceprevir. We characterized innate and adaptive immune cells to determine whether kinetics of the host response could predict sustained virologic response (SVR). We show that characteristics of the host immune system present before treatment were correlated with successful therapy. Augmentation of adaptive immune responses during therapy was more impressive among those achieving SVR. Most importantly, active memory T cell proliferation before therapy predicted SVR and was associated with the magnitude of the HCV-specific responses at week 12 after treatment start. After therapy initiation, the most important correlate of success was minimal monocyte activation, as predicted by previous in vitro work. In addition, subjects achieving SVR had increasing expression of the transcription factor T-bet, a driver of Th1 differentiation and cytotoxic effector cell maturation. These results show that host immune features present before treatment initiation predict SVR and eventual development of a higher frequency of functional virus-specific cells in blood. Such host characteristics may also be required for successful vaccine-mediated protection.

IL-33 promotes growth and liver metastasis of colorectal cancer in mice by remodeling the tumor microenvironment and inducing angiogenesis.

Liver metastasis is the major cause of death from colorectal cancer (CRC). Understanding its mechanisms is necessary for timely diagnosis and development of effective therapies. Interleukin-33 (IL-33) is an IL-1 cytokine family member that uniquely functions as a cytokine and nuclear factor. It is released by necrotic epithelial cells and activated innate immune cells, functioning as an alarmin or an early danger signal. Its role in invoking type 2 immune response has been established; however, it has contrasting roles in tumor development and metastasis. We identified IL-33 as a potently upregulated cytokine in a highly metastatic murine CRC cell line and examined its role in tumor growth and metastasis to the liver. IL-33 was transgenically expressed in murine and human adenocarcinoma and carcinoma cell lines and their growth and spontaneous metastasis to the liver were assessed in orthotopic models of CRC in wild-type C57Bl/6 and Il33 knockout mice. The results showed that increased expression of IL-33 in CRC cells enhanced their tumor take, growth, and liver metastasis. Tumor- rather than host-derived IL-33 induced the enhanced recruitment of CD11b+ GR1+ and CD11b+ F4/80+ myeloid cells to remodel the tumor microenvironment by increased expression of mobilizing cytokines, and tumor angiogenesis by activating endothelial cells. IL-33 expression was elevated in patient tumor tissues, induced early in adenoma development, and activated by pro-inflammatory cytokines derived from the tumor microenvironment. The data suggest that tumor-derived IL-33 modulates the tumor microenvironment to potently promote colon carcinogenesis and liver metastasis, underscoring its potential as a therapeutic target. © 2016 Wiley Periodicals, Inc.

NKG2D ligand expression in Crohn's disease and NKG2D-dependent stimulation of CD8+ T cell migration.

Interaction between the activating NKG2D receptor on lymphocytes and its ligands MICA, MICB, and ULBP1-6 modulate T and NK cell activity and may contribute to the pathogenesis of Crohn's disease (CD). NKG2D ligands are generally not expressed on the cell surface of normal, non-stressed cells, but expression of MICA and MICB in CD intestine has been reported. In this exploratory study, we further characterize the expression of NKG2D and its ligands, including the less well-described ULBP4-6, in CD, and test if NKG2D ligand interactions are involved in the migration of activated T cells into the affected mucosal compartments. Intestinal tissue from CD patients and healthy controls were analyzed by flow cytometry, mass cytometry, and immunohistochemistry for expression of NKG2D and ligands, and for cytokine release. Furthermore, NKG2D-dependent chemotaxis of activated CD8+ T cells across a monolayer of ligand-expressing human intestinal endothelial cells was examined. Activated lymphocytes down-regulated NKG2D expression upon accumulation in inflamed CD intestine. NKG2D expression on CD56+ T and γδ T cells from inflamed tissue seemed inversely correlated with CRP levels and cytokine release. B cells, monocytes, mucosal epithelium, and vascular endothelium expressed NKG2D ligands in inflamed CD intestine. The expression of NKG2D ligands was correlated with cytokine release, but was highly variable between patients. Stimulation of vascular intestinal endothelial cells in vitro induced expression of NKG2D ligands, including MICA/B and ULBP2/6. Blockade of NKG2D on CD8+ T cells inhibited the migration over ligand-expressing endothelial cells. Intestinal induction of NKG2D ligands and ligand-induced down-regulation of NKG2D in CD suggest that the NKG2D-ligand interaction may be involved in both the activation and recruitment of NKG2D+ lymphocytes into the inflamed CD intestine.

Improved Survival Among all Interferon-α-Treated Patients in HCV-002, a Veterans Affairs Hepatitis C Cohort of 2211 Patients, Despite Increased Cirrhosis Among Nonresponders.

BACKGROUND: As the era of interferon-alpha (IFN)-based therapy for hepatitis C ends, long-term treatment outcomes are now being evaluated. AIM: To more fully understand the natural history of hepatitis C infection by following a multisite cohort of patients. METHODS: Patients with chronic HCV were prospectively enrolled in 1999-2000 from 11 VA medical centers and followed through retrospective medical record review. RESULTS: A total of 2211 patients were followed for an average of 8.5 years after enrollment. Thirty-one percent of patients received HCV antiviral therapy, 15 % with standard IFN/ribavirin only, 16 % with pegylated IFN/ribavirin, and 26.7 % of treated patients achieved sustained virologic response (SVR). Cirrhosis developed in 25.8 % of patients. Treatment nonresponders had a greater than twofold increase in the hazard of cirrhosis and hepatocellular carcinoma, compared to untreated patients, whereas SVR patients were only marginally protected from cirrhosis. Nearly 6 % developed hepatocellular carcinoma, and 27.1 % died during the follow-up period. Treated patients, regardless of response, had a significant survival benefit compared to untreated patients (HR 0.58, CI 0.46-0.72). Improved survival was also associated with college education, younger age, lower levels of alcohol consumption, and longer duration of medical service follow-up-factors typically associated with treatment eligibility. CONCLUSIONS: As more hepatitis C patients are now being assessed for all-oral combination therapy, these results highlight that patient compliance and limiting harmful behaviors contribute a significant proportion of the survival benefit in treated patients and that the long-term clinical benefits of SVR may be less profound than previously reported.

Protective association of colonoscopy against proximal and distal colon cancer and patterns in interval cancer.

BACKGROUND: The protective effect of colonoscopy against proximal colorectal cancer is variable and depends on the detection and complete removal of precancerous polyps. OBJECTIVE: To estimate the efficacy of colonoscopy in a medical center with open-access screening colonoscopy since 1998. DESIGN: Nested case-control study with incidence density sampling. SETTING: University-affiliated Veterans Affairs Medical Center. PATIENTS: Colorectal cancer (CRC) cases and control subjects selected from screening age patients matched by age, gender, and date of first primary care visit. MAIN OUTCOME MEASUREMENT: Colonoscopy preceding the CRC diagnosis date. RESULTS: A total of 20.2% of CRC cases had a colonoscopy in the preceding 10 years compared with 49.0% of control subjects (adjusted odds ratio [aOR], 0.20; 95% confidence interval [CI], 0.11-0.34). Colonoscopy was strongly associated with decreased odds of both distal CRC (aOR, 0.16; 95% CI, 0.07-0.34) and proximal CRC (aOR, 0.26; 95% CI, 0.11-0.58). The fraction of cases attributed to interval cancers was 10.5%. Missed lesions predominantly localized to the cecum and rectum, and recurrent lesions clustered in the hepatic flexure. Cecal intubation rate was 93% (98% in adequately prepped patients), and the adenoma detection rate was 45.2% in the control group. LIMITATIONS: Single-center, retrospective case-control design. CONCLUSION: In an open access colonoscopy program characterized by a high cecal intubation rate and adenoma detection rate, colonoscopy was strongly associated with reduced odds of both distal and proximal CRC. Among interval cancers, missed lesions clustered in the cecum and rectum and recurrent lesions in the hepatic flexure.

Monocyte activation by interferon α is associated with failure to achieve a sustained virologic response after treatment for hepatitis C virus infection.

BACKGROUND: Interferon α (IFN-α) and ribavirin can induce a sustained virologic response (SVR) in some but not all hepatitis C virus (HCV)-infected patients. The mechanism of effective treatment is unclear. One possibility is that IFN-α differentially improves the functional capacity of classic myeloid dendritic cells (mDCs) by altering expression of surface molecules or cytokines. Others have proposed that antigen-presenting cell activation could be paradoxically detrimental during HCV infection because of the production by monocytes of substances inhibitory or toxic to plasmacytoid dendritic cells. METHODS: We examined responses to in vitro IFN-α treatment of peripheral blood leukocyte samples from a retrospective treatment cohort of nearly 200 HCV-seropositive patients who had undergone antiviral therapy with ribavirin and pegylated IFN. We analyzed the variable responses of antigen-presenting cell subsets to drug. RESULTS: We found that patients achieving SVR were no more likely to have robust mDC activation in response to IFN-α than those who did not achieve SVR. Rather, patients achieving SVR were distinguished by restrained monocyte activation in the presence of IFN-α, a factor that was second in importance only to IL28B genotype in its association with SVR. CONCLUSIONS: These results suggest that interindividual variability in the response of monocytes to IFN-α is an important determinant of treatment success with IFN-α-based regimens.

Expanded use of aggressive therapies improves survival in early and intermediate hepatocellular carcinoma.

BACKGROUND: Despite the increasing annual incidence of hepatocellular carcinoma (HCC) in the USA, now estimated at 2.7 cases per 100 000 population, only a small proportion of patients receive treatment and 5-year survival rates range from 9% to 17%. OBJECTIVES: The present study examines the effects of multimodal treatment on survival in a mixed-stage HCC cohort, focusing on the impact of radical therapy in patients with Barcelona Clinic Liver Cancer (BCLC) stage B disease. METHODS: A retrospective review of the medical records of 254 patients considered for HCC treatment between 2003 and 2011 at a large tertiary referral centre was conducted. RESULTS: A total of 195 (76.8%) patients were treated with a median of two liver-directed interventions. Median survival time was 16 months. In proportional hazards analysis, radiofrequency ablation (RFA) and resection were associated with significantly improved 1- and 5-year survival among patients with BCLC stage 0-A disease. In patients with BCLC stage B disease, RFA conferred a survival benefit at 1 year and resection was associated with significantly improved survival at 5 years. CONCLUSIONS: As one of few studies to track the complete course of sequential HCC therapies, the findings of the present study suggest that HCC patients with intermediate-stage (BCLC stage B) disease may benefit from aggressive interventions not currently included in societal guidelines.