Association between serum high-molecular-weight adiponectin level and the severity of chronic graft-versus-host disease in allogeneic stem cell transplantation recipients

Metabolic syndrome prevalence and impact on outcomes in patients with chronic graft-versus-host disease

Patients with chronic graft-versus-host disease (cGVHD) are at heightened risk for components of metabolic syndrome (MetS), yet the prevalence and impact of MetS in the cGVHD patient population remain unknown. Adult patients (n = 229) with cGVHD enrolled in the cross-sectional NIH cGVHD Natural History Study (NCT00092235) were evaluated for MetS at enrollment and for variables associated with MetS. A majority (54.1%, 124/229) of the cohort met the diagnostic criteria for MetS. Patients with higher body mass index and lower performance status scores were more likely to have MetS (P < 0.0001; P = 0.026; respectively). Higher circulating erythrocyte sedimentation rate, C-reactive protein, and creatinine concentrations, along with lower estimated glomerular filtration rate, were associated with MetS (P < 0.001; P < 0.004; P = 0.02; P = 0.002; respectively). Patients with MetS compared to patients without MetS had no statistical differences in survival or NRM (5-year OS: 64% [95% CI: 54.8-71.8%] vs. 75.1% [95% CI: 65.6-82.3%]; respectively; overall P = 0.20; 5-year NRM: 21.7% [95% CI: 13.6-30.9%] vs. 10.1% [95% CI: 4.4-18.7%]; respectively; overall P = 0.12). Additionally, there was no difference in cGVHD severity between the two groups. Given the high prevalence of MetS in this cohort, clinicians should screen for its presence before it develops into comorbidities that complicate the course of cGVHD treatment.

Methods to Assess Disease Activity and Severity in Cutaneous Chronic Graft-versus-Host Disease: A Critical Literature Review

Chronic graft-versus-host disease (cGVHD), a potentially debilitating complication of hematopoietic cell transplantation, confers increased risk for mortality. Whereas treatment decisions rely on an accurate assessment of disease activity/severity, validated methods of assessing cutaneous cGVHD activity/severity appear to be limited. In this study, we aimed to identify and evaluate current data on the assessment of disease activity/severity in cutaneous cGVHD. Using modified PRISMA methods, we performed a critical literature review for relevant articles. Our literature search identified 1741 articles, of which 1635 were excluded as duplicates or failure to meet inclusion criteria. Of the included studies (n = 106), 39 (37%) addressed clinical and/or histopathologic parameters, 53 (50%) addressed serologic parameters, 8 (7.5%) addressed imaging parameters, and 6 (5.5%) addressed computer-based technologies. The only formally validated metric of disease activity/severity assessment in cutaneous cGVHD is the National Institutes of Health consensus scoring system, which is founded on clinical assessment alone. The lack of an objective marker for cGVHD necessitates further studies. An evaluation of the potential contributions of serologic, imaging, and/or computer-based technologies is warranted.

Proinflammatory Cytokine and Adipokine Levels in Adult Unrelated Marrow Donors Are Not Associated with Hematopoietic Cell Transplantation Outcomes

Graft-versus-host disease (GVHD) is a frequent cause of morbidity and mortality after allogeneic hematopoietic cell transplantation (allo-HCT). GVHD occurs when donor lymphocytes are activated by inflammatory cytokines and alloantigens. The role of donor biologic characteristics, such as basal inflammation, has not been investigated as a risk factor for GVHD but is theoretically transferrable to the recipient. We evaluated donor serum and plasma concentrations of cytokines and adipokines (IL-1β, IL-6, tumor necrosis factor [TNF]-α, leptin, suppression of tumorigenicity-2, and adiponectin) from test (n = 210) and replication (n = 250) cohorts of matched, unrelated transplant peripheral blood stem cell recipients identified through the Center for International Blood and Marrow Transplantation Research between 2000 and 2011 for hematologic malignancies. Hazard ratios were estimated for acute (grades II to IV and III to IV) and chronic GVHD, overall survival, disease-free survival, transplant-related mortality, and relapse for each cytokine or adipokine, adjusting for significant covariates. The lowest cytokine quartile was considered as the reference group for each model. To account for multiple testing P < .01 was considered the threshold for significance. In the test cohort a borderline significant association was identified between donor serum IL-1β concentrations and grades III to IV acute GVHD in the recipient (P = .01), and a significant inverse association was identified between donor TNF-α concentrations and chronic GVHD (P = .006). These findings were not validated in the replication cohort. Although the initial associations between cytokine levels and allo-HCT outcomes were not validated, the idea that donor characteristics may be transferable to the recipient remains an exciting area for future research.

Vascular Alterations in a Murine Model of Acute Graft-Versus-Host Disease Are Associated with Decreased Serum Levels of Adiponectin and an Increased Activity and Vascular Expression of Indoleamine 2,3-Dioxygenase

Graft-versus-host disease (GVHD) is the limiting complication after bone marrow transplantation (BMT), and its pathophysiology seems to be highly influenced by vascular factors. Our study aimed at elucidating possible mechanisms involved in vascular GVHD. For this purpose, we used a fully MHC-mismatched model of BALB/c mice conditioned according to two different intensity protocols with total body irradiation and transplantation of allogeneic (C57BL/6) or syngeneic bone marrow cells and splenocytes. Mesenteric resistance arteries were studied in a pressurized myograph. We also quantified the expression of indoleamine 2,3-dioxygenase (IDO), endothelial (eNOS), and inducible NO synthase (iNOS), as well as several pro- and anti-inflammatory cytokines. We measured the serum levels of tryptophan (trp) and kynurenine (kyn), the kyn/trp ratio (KTR) as a marker of IDO activity, and adiponectin (APN). The myographic study showed a correlation of GVHD severity after allogeneic BMT with functional vessel alterations that started with increased vessel stress and ended in eccentric vessel remodeling, increased vessel strain, and endothelial dysfunction. These alterations were accompanied by increasing IDO activity and decreasing APN levels in the serum of allogeneic animals. The mRNA expression showed significantly elevated IDO, decreased eNOS, and elevation of most studied pro- and anti-inflammatory cytokines. Our study provides further data supporting the importance of vessel alterations in GVHD and is the first to show an association of vascular GVHD with hypoadiponectinemia and an increased activity and vascular expression of IDO. Whether there is also a causative involvement of these two factors in the development of GVHD needs to be further investigated.

Glycoprotein YKL-40: a novel biomarker of chronic graft-vs-host disease activity and severity?

AIM

To investigate whether increased YKL-40 levels positively correlate with graft-vs-host disease (cGVHD) activity and severity and if YKL-40 could serve as a disease biomarker.

METHODS

This case-control study was conducted at the University Hospital Centre Zagreb from July 2013 to October 2015. 56 patients treated with hematopoietic stem cell transplantation (HSCT) were included: 35 patients with cGVHD and 21 without cGVHD. There was no difference between groups in age, sex, median time from transplant to study enrollment, intensity of conditioning, type of donor, or source of stem cells. Blood samples were collected at study enrollment and YKL-40 levels were measured with ELISA. Disease activity was estimated using Clinician's Impression of Activity and Intensity of Immunosuppression scales and disease severity using Global National Institutes of Health (NIH) score.

RESULTS

YKL-40 levels were significantly higher in cGVHD patients than in controls (P=0.003). The difference remained significant when patients with myelofibrosis were excluded from the analysis (P=0.017). YKL-40 level significantly positively correlated with disease severity (P<0.001; correlation coefficient 0.455), and activity estimated using Clinician's Impression of Activity (P=0.016; correlation coefficient 0.412) but not using Intensity of Immunosuppression (P=0.085; correlation coefficient 0.296).

CONCLUSION

YKL-40 could be considered a biomarker of cGVHD severity and activity. However, validation in a larger group of patients is warranted, as well as longitudinal testing of YKL-40 levels in patients at risk of developing cGVHD.

Adiponectin and resistin in acute and chronic graft-vs-host disease patients undergoing allogeneic hematopoietic stem cell transplantation

Aim

To investigate the association of adiponectin and resistin levels in patients undergoing hematopoietic stem cell transplantation (HSCT) with the clinical outcome, including the occurrence of acute and chronic graft-vs-host disease (GVHD), non-relapse mortality, and overall survival.

Methods

We prospectively collected serum samples from 40 patients undergoing either autologous (n = 12; 10 male) or allogeneic (n = 28; 11 male) HSCT for up to 12 months post HSCT and determined adiponectin and resistin serum concentrations using enzyme-linked immunosorbent assay.

Results

There were no significant differences in adiponectin levels (18.5 vs 9.3 µg/mL, P = 0.071) and adiponectin/BMI ratio (0.82 vs 0.39, P = 0.068) between patients with acute GVHD grades 2-4 and autologous controls. However, resistin values were significantly lower in patients with acute GVHD grades 2-4 than in autologous controls (4.6 vs 7.3 ng/mL, P = 0.030). Adiponectin levels were higher in patients with chronic GVHD (n = 17) than in autologous controls (13.5 vs 7.6 µg/mL, P = 0.051), but the difference was not significant. Adiponectin/BMI ratio was significantly higher in patients with chronic GVHD than in autologous controls (0.59 vs 0.25, P = 0.006). Patients dying from relapse also had significantly lower adiponectin levels (8.2 µg/mL) and adiponectin/BMI ratio (0.3) on admission than surviving allogeneic (15.8 µg/mL, P = 0.030 and 0.7, P = 0.004) and surviving autologous patients (19.2 µg/mL, P = 0.031 and 0.7, P = 0.021).

Conclusion

Adiponectin and resistin levels were altered in patients with acute and chronic GVHD compared to autologous controls and were associated with overall survival and relapse mortality in patients undergoing allogeneic HSCT.

Therapeutic benefits targeting B-cells in chronic graft-versus-host disease

Allogeneic hematopoietic cell transplantation (allo-HCT) can be a curative strategy for hematological diseases, and the indications for allo-HCT have broadened widely due to recent progress in supportive strategies. However, patients must overcome various complications and chronic graft-versus-host disease (cGVHD) remains the most common allo-HCT cause of long-term morbidity and mortality. cGVHD is difficult to biologically assess due to the heterogeneity of cGVHD symptoms, and the pathogenesis of cGVHD has yet to be established. Recent experimental model progress has suggested that B-cells play a critical role in cGVHD development. Consistent with these experimental results, some clinical studies investigating B-cell depletion and modulation of B-cell signaling pathways have decreased cGVHD incidence and provided some therapeutic benefit. However, randomized control studies are necessary to confirm the efficacy of B-cell targeting drugs for cGVHD. Here, we review the pathophysiology of cGVHD, especially focusing on the role of B-cell immunity, and discuss the efficacy of both B-cell depletion and modulation of B-cell signaling pathways in human cGVHD prevention, initial treatment, and salvage treatment.

Current issues in chronic graft-versus-host disease

Chronic graft-versus-host disease (GVHD) is a frequent and potentially life-threatening complication of allogeneic hematopoietic stem cell transplantation. Increased transplantation of older patients and the more frequent use of unrelated donors has led to increased numbers of patients with this painful complication. Recent advances have been made in understanding the pathophysiology of chronic GVHD and in establishing precise criteria for diagnosis and classification of disease manifestations. These advances will hopefully pave the way for improving both the prophylaxis and treatment of chronic GVHD.

Current issues in chronic graft-versus-host disease

Chronic graft-versus-host disease (GVHD) is a frequent and potentially life-threatening complication of allogeneic hematopoietic stem cell transplantation. Increased transplantation of older patients and the more frequent use of unrelated donors has led to increased numbers of patients with this painful complication. Recent advances have been made in understanding the pathophysiology of chronic GVHD and in establishing precise criteria for diagnosis and classification of disease manifestations. These advances will hopefully pave the way for improving both the prophylaxis and treatment of chronic GVHD.

Effect of body mass in children with hematologic malignancies undergoing allogeneic bone marrow transplantation

The rising incidence of pediatric obesity may significantly affect bone marrow transplantation (BMT) outcomes. We analyzed outcomes in 3687 children worldwide who received cyclophosphamide-based BMT regimens for leukemias between 1990 and 2007. Recipients were classified according to age-adjusted body mass index (BMI) percentiles as underweight (UW), at risk of UW (RUW), normal, overweight (OW), or obese (OB). Median age and race were similar in all groups. Sixty-one percent of OB children were from the United States/Canada. Three-year relapse-free and overall survival ranged from 48% to 52% (P = .54) and 55% to 58% (P = .81) across BMI groups. Three-year leukemia relapses were 33%, 33%, 29%, 25%, and 21% in the UW, RUW, normal, OW, and OB groups, respectively (P < .001). Corresponding cumulative incidences for transplant-related mortality (TRM) were 18%, 19%, 21%, 22%, and 28% (P < .01). Multivariate analysis demonstrated a decreased risk of relapse compared with normal BMI (relative risk [RR] = 0.73; P < .01) and a trend toward higher TRM (RR = 1.28; P = .014). BMI in children is not significantly associated with different survival after BMT for hematologic malignancies. Obese children experience less relapse posttransplant compared with children with normal BMI; however, this benefit is offset by excess in TRM.

Impact of high-/middle-molecular-weight adiponectin on the synthesis and regulation of extracellular matrix in dermal fibroblasts

Adiponectin has been shown to play a critical role in immunity. Recently, we reported that the adiponectin levels after allogeneic stem cell transplantation were higher in recipients with chronic graft-versus-host disease (cGVHD). However, the effects of adiponectin on extracellular matrix (ECM) and regulatory factors in dermal fibroblasts remain unclear. We compared the messenger RNA (mRNA) levels of collagen type1 (COL1A), fibronectin 1 (FN1), matrix metalloproteinase (MMP)1, MMP3, tissue inhibitor of metalloproteinase (TIMP)1, TIMP3, transforming growth factor-β (TGF-β), and TGF-β receptor 2 (TGF-βR2) in human normal dermal fibroblasts cultured with and without adiponectin, and we assessed the degree of synthesis of ECMs by immunofluorescent microscopy. Furthermore, we also assessed these mRNA levels after blocking of TGF-βR2. Adiponectin induced higher mRNA levels of FN1, MMP1, MMP3, TIMP1, TIMP3, and TGF-βR2 in a dose-dependent manner, but did not significantly affect COL1A or TGF-β. In addition, adiponectin was shown to upregulate FN1, MMPs, and TIMPs after blocking of TGF-βR2. Immunofluorescent microscopy revealed that adiponectin promoted a greater synthesis of ECMs than in the control in vitro. The finding that adiponectin upregulated ECM-associated factors might mean that high levels of adiponectin could modulate dermal fibrosis was observed in recipients with cGVHD. Further basic investigation is warranted to elucidate whether the adiponectin-pathway could be a target for the treatment of sclerotic cGVHD.

Adiponectin in inflammatory and immune-mediated diseases

Circulating levels of adiponectin (APN) are reduced in obesity and associated comorbidities, with inflammation playing an important role in downregulating APN production. In contrast to obesity and metabolic disease, elevated systemic and local levels of APN are present in patients with inflammatory and immune-mediated diseases, including autoimmune and pulmonary conditions, heart and kidney failure, viral hepatitis, organ transplantation and perhaps critical illness. A positive association between inflammation and APN is usually reported in inflammatory/immune pathologies, in contrast with the negative correlation typical of metabolic disease. This review discusses the role of APN in modulation of inflammation and immunity and the potential mechanisms leading to increased levels of APN in inflammatory/immune diseases, including modification of adipose tissue physiology; relative contribution of different tissues and adipose depots; hormonal, pharmacological, nutritional and life style factors; the potential contribution of the microbiota as well as the role of altered APN clearance and release from T-cadherin-associated tissue reservoirs. Potential reasons for some of the apparently contradictory findings on the role of APN as a modulator of immunity and inflammation are also discussed, including a comparison of types of recombinant APN used for in vitro studies and strain-dependent differences in the phenotype of APN KO mice.

Toxicant-associated steatohepatitis

Hepatotoxicity is the most common organ injury due to occupational and environmental exposures to industrial chemicals. A wide range of liver pathologies ranging from necrosis to cancer have been observed following chemical exposures both in humans and in animal models. Toxicant-associated fatty liver disease (TAFLD) is a recently named form of liver injury pathologically similar to alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD). Toxicant-associated steatohepatitis (TASH) is a more severe form of TAFLD characterized by hepatic steatosis, inflammatory infiltrate, and in some cases, fibrosis. While subjects with TASH have exposures to industrial chemicals, such as vinyl chloride, they do not have traditional risk factors for fatty liver such as significant alcohol consumption or obesity. Conventional biomarkers of hepatotoxicity including serum alanine aminotransferase activity may be normal in TASH, making screening problematic. This article examines selected chemical exposures associated with TAFLD in human subjects or animal models and concisely reviews the closely related NAFLD and ALD.