High serum sCD163/sTWEAK ratio is associated with lower risk of digital ulcers but more severe skin disease in patients with systemic sclerosis

Introduction

Systemic sclerosis (SSc) is an autoimmune disease characterized by chronic inflammation, vascular injury and excessive fibrosis. CD163 is a scavenger receptor which affects inflammatory response and may contribute to connective tissue remodelling. It has recently been demonstrated that CD163 can bind and neutralize the TNF-like weak inducer of apoptosis (TWEAK), a multifunctional cytokine which regulates inflammation, angiogenesis and tissue remodelling. We aimed to investigate the relationships between serum levels of soluble CD163 (sCD163) and soluble TWEAK (sTWEAK) in relation to disease manifestations in SSc patients.

Methods

This study included 89 patients with SSc who had not received immunosuppressive drugs or steroids for at least 6 months and 48 age- and sex-matched healthy controls (HC) from four European centres. Serum concentrations of sTWEAK and sCD163 were measured using commercially available ELISA kits.

Results

The mean serum concentrations of sTWEAK were comparable between SSc patients (mean +/- SD: 270 +/- 171 pg/mL) and HC (294 +/- 147pg/mL, P >0.05). Concentration of sCD163 and sCD163/sTWEAK ratio were significantly greater in SSc patients (984 +/- 420 ng/mL and 4837 +/- 3103, respectively) as compared to HC (823 +/- 331 ng/mL and 3115 +/- 1346 respectively, P <0.05 for both). High sCD163 levels and a high sCD163/sTWEAK ratio (defined as > mean +2SD of HC) were both associated with a lower risk of digital ulcers in SSc patients (OR, 95%CI: 0.09; 0.01, 0.71, and 0.17; 0.06, 0.51, respectively). Accordingly, patients without digital ulcers had a significantly higher sCD163 concentration and sCD163/sTWEAK ratio as compared to SSc patients with digital ulcers (P <0.01 for both) and HC (P <0.05 for both). A high sCD163/sTWEAK ratio, but not high sCD163 levels, was associated with greater skin involvement.

Conclusions

The results of our study indicate that CD163-TWEAK interactions might play a role in the pathogenesis of SSc and that CD163 may protect against the development of digital ulcers in SSc. Further studies are required to reveal whether targeting of the CD163-TWEAK pathway might be a potential strategy for treating vascular disease and/or skin fibrosis in SSc.     

Dysregulated Immune Activation in Second-Line HAART HIV+ Patients Is Similar to That of Untreated Patients

Background

Successful highly active antiretroviral therapy (HAART) has changed the outcome of AIDS patients worldwide because the complete suppression of viremia improves health and prolongs life expectancy of HIV-1+ patients. However, little attention has been given to the immunological profile of patients under distinct HAART regimens. This work aimed to investigate the differences in the immunological pattern of HIV-1+ patients under the first- or second-line HAART in Brazil.

Methods

CD4+ T cell counts, Viral load, and plasma concentration of sCD14, sCD163, MCP-1, RANTES, IP-10, IL-1β, IL-6, TNF-α, IL-12, IFN-α, IFN-γ, IL-4, IL-5, and IL-10 were assessed for immunological characterization of the following clinical groups: Non-infected individuals (NI; n = 66), HIV-1+ untreated (HIV; n = 46), HIV-1+ treated with first-line HAART (HAART 1; n = 15); and HIV-1+ treated with second-line HAART (HAART 2; n = 15).

Results

We found that the immunological biosignature pattern of HAART 1 is similar to that of NI individuals, especially in patients presenting slow progression of the disease, while patients under HAART 2 remain in a moderate inflammatory state, which is similar to that of untreated HIV patients pattern. Network correlations revealed that differences in IP-10, TNF-α, IL-6, IFN-α, and IL-10 interactions were primordial in HIV disease and treatment. Heat map and decision tree analysis identified that IP-10>TNF-α>IFN-α were the best respective HAART segregation biomarkers.

Conclusion

HIV patients in different HAART regimens develop distinct immunological biosignature, introducing a novel perspective into disease outcome and potential new therapies that consider HAART patients as a heterogeneous group.     

Serum Levels of TWEAK and Scavenger Receptor CD163 in Type 1 Diabetes Mellitus: Relationship with Cardiovascular Risk Factors. A Case-Control Study

Objective

To test the usefulness of serum concentrations of tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) and soluble scavenger receptor CD163 (sCD163) as markers of subtle inflammation in patients with type 1 diabetes mellitus (T1DM) without clinical cardiovascular (CV) disease and to evaluate their relationship with arterial stiffness (AS).

Methods

Sixty-eight patients with T1DM and 68 age and sex-matched, healthy subjects were evaluated. Anthropometrical variables and CV risk factors were recorded. Serum concentrations of sTWEAK and sCD163 were measured. AS was assessed by aortic pulse wave velocity (aPWV). All statistical analyses were stratified by gender.

Results

T1DM patients showed lower serum concentrations of sTWEAK (Men: 1636.5 (1146.3–3754.8) pg/mL vs. 765.9 (650.4–1097.1) pg/mL; p<0.001. Women: 1401.0 (788.0–2422.2) pg/mL vs. 830.1 (562.6–1175.9) pg/mL; p = 0.011) compared with their respective controls. Additionally, T1DM men had higher serum concentrations of sCD163 (285.0 (247.7–357.1) ng/mL vs. 224.8 (193.3–296.5) ng/mL; p = 0.012) compared with their respective controls. sTWEAK correlated negatively with aPWV in men (r = −0.443; p<0.001). However, this association disappeared after adjusting for potential confounders. In men, the best multiple linear regression model showed that the independent predictors of sTWEAK were T1DM and WHR (R² = 0.640; p<0.001). In women, T1DM and SBP were the independent predictors for sTWEAK (R² = 0.231; p = 0.001).

Conclusion

sTWEAK is decreased in T1DM patients compared with age and sex-matched healthy subjects after adjusting for classic CV risk factors, although sTWEAK levels may be partially influenced by some of them. Additionally, T1DM men have higher serum concentrations of sCD163. These results point out an association between the inflammatory system and CV risk in T1DM.     

Biomarkers of Inflammation and Axonal Degeneration/Damage in Patients with Newly Diagnosed Multiple Sclerosis: Contributions of the Soluble CD163 CSF/Serum Ratio to a Biomarker Panel

Background

Expression of soluble CD163 (sCD163), a macrophage/microglia biomarker, is increased in inflammatory conditions, and sCD163 levels in the cerebrospinal fluid (CSF) have recently been shown to be elevated in patients with multiple sclerosis (MS): the sCD163 CSF/serum ratio was elevated in patients with relapsing-remitting MS (RRMS), primary progressive MS (PPMS), and clinically isolated syndrome (CIS) compared with symptomatic controls.

Objective

To investigate the contributions of the sCD163 CSF/serum ratio to a biomarker panel focusing on inflammation and axonal degeneration in newly diagnosed MS; thus optimising a diagnostic biomarker panel for MS.

Methods

After a full MS diagnostic work-up, including collection of paired samples of CSF and serum, 125 patients were included in this study. Patients were divided into groups based on their diagnosis, and patients with normal clinical and paraclinical findings were defined as symptomatic controls. Serum and CSF levels, ratios, and indices of sCD163, CXCL13, osteopontin, neopterin, and CSF levels of neurofilament light polypeptide were determined by enzyme-linked immunosorbent assays (ELISAs). For sCD163 the results constitute a post-hoc analysis of already published data.

Results

All tested biomarkers, notably the sCD163 ratio, the CXCL13 ratio, the NEO ratio, the CSF level of NfL, the IgG index, and the serum level of OPN, were significantly correlated to RRMS, PPMS, and/or CIS. The individual biomarkers in single tests had a lower performance than the IgG index, however, their combined receiver operating characteristic (ROC) curve demonstrated excellent diagnostic discriminatory power.

Conclusion

The biomarker panel showed distinct profiles for each patient group and could be a valuable tool for clinical differentiation of MS subgroups. The combined ROC analysis showed that sCD163 contributes positively as a diagnostic marker to a panel of established MS biomarkers. Patients with PPMS were demonstrated to have significantly elevated levels of both inflammatory and degenerative markers.     

Urinary TWEAK as a biomarker of lupus nephritis: a multicenter cohort study

Introduction

TNF-like weak inducer of apoptosis (TWEAK) has been implicated as a mediator of chronic inflammatory processes via prolonged activation of the NF-κB pathway in several tissues, including the kidney. Evidence for the importance of TWEAK in the pathogenesis of lupus nephritis (LN) has been recently introduced. Thus, TWEAK levels may serve as an indication of LN presence and activity.

Methods

Multicenter cohorts of systemic lupus erythematosus (SLE) patients and controls were recruited for cross-sectional and longitudinal analysis of urinary TWEAK (uTWEAK) and/or serum TWEAK (sTWEAK) levels as potential biomarkers of LN. The performance of TWEAK as a biomarker for nephritis was compared with routinely used laboratory tests in lupus patients, including anti-double stranded DNA antibodies and levels of C3 and C4.

Results

uTWEAK levels were significantly higher in LN patients than in non-LN SLE patients and other disease control groups (P = 0.039). Furthermore, uTWEAK was better at distinguishing between LN and non-LN SLE patients than anti-DNA antibodies and complement levels, while high uTWEAK levels predicted LN in SLE patients with an odds ratio of 7.36 (95% confidence interval = 2.25 to 24.07; P = 0.001). uTWEAK levels peaked during LN flares, and were significantly higher during the flare than at 4 and 6 months prior to or following the flare event. A linear mixed-effects model showed a significant association between uTWEAK levels in SLE patients and their disease activity over time (P = 0.008). sTWEAK levels, however, were not found to correlate with the presence of LN or the degree of nephritis activity.

Conclusions

High uTWEAK levels are indicative of LN, as opposed to non-LN SLE and other healthy and disease control populations, and reflect renal disease activity in longitudinal follow-up. Thus, our study further supports a role for TWEAK in the pathogenesis of LN, and provides strong evidence for uTWEAK as a candidate clinical biomarker for LN.     

Chronic Endotoxemia in Subjects with Type-1 Diabetes Is Seen Much before the Onset of Microvascular Complications

Background

Lipopolysaccharide (LPS)/Endotoxin is hypothesized to play an important role in chronic inflammation associated with Type-1 diabetes (T1DM) and its complications. Endotoxin core antibodies (EndoCAb), LPS binding protein (LBP) and soluble CD14 (sCD14) act as modulators of LPS induced activation of innate immune system in vivo. For the present study we estimated the levels of LPS and its translocation markers in T1DM subjects with and without microvascular complications (MVC) and correlate them with clinical parameters of T1DM and serum inflammatory cytokine levels (TNF-α, IL-6, IL-1β and GM-CSF).

Methods

A total of 197 subjects (64 normal glucose tolerance (NGT) subjects, 97 T1DM subjects without MVC and 36 with MVC) were included in this study and the levels of serum LPS, its translocation markers and cytokines measured by immunoassays.

Results

Compared to NGT, T1DM subjects (both with and without MVC) had significantly higher levels of LPS, reduced levels of LBP and EndoCAb along with significant increase in the levels of IL-1β, IL-6, TNF-α and GM-CSF (p<0.05). No significant change was seen in the levels of these biomarkers between T1DM subjects with and without MVC.

Conclusions

Decreased levels of EndoCAb and LBP suggest sustained endotoxin activity in T1DM subjects even before the onset of microvascular complications.     

Changes in Soluble CD18 in Murine Autoimmune Arthritis and Rheumatoid Arthritis Reflect Disease Establishment and Treatment Response

Introduction

In rheumatoid arthritis (RA) immune activation and presence of autoantibodies may precede clinical onset of disease, and joint destruction can progress despite remission. However, the underlying temporal changes of such immune system abnormalities in the inflammatory response during treat-to-target strategies remain poorly understood. We have previously reported low levels of the soluble form of CD18 (sCD18) in plasma from patients with chronic RA and spondyloarthritis. Here, we study the changes of sCD18 before and during treatment of early RA and following arthritis induction in murine models of rheumatoid arthritis.

Methods

The level of sCD18 was analyzed with a time-resolved immunoflourometric assay in 1) plasma from early treatment naïve RA patients during a treat-to-target strategy (the OPERA cohort), 2) plasma from chronic RA patients, 3) serum from SKG and CIA mice following arthritis induction, and 4) supernatants from synovial fluid mononuclear cells (SFMCs) and peripheral blood mononuclear cells (PBMCs) from 6 RA patients cultured with TNFα or adalimumab.

Results

Plasma levels of sCD18 were decreased in chronic RA patients compared with early RA patients and in early RA patients compared with healthy controls. After 12 months of treatment the levels in early RA patients were similar to healthy controls. This normalization of plasma sCD18 levels was more pronounced in patients with very early disease who achieved an early ACR response. Plasma sCD18 levels were associated with radiographic progression. Correspondingly, the serum level of sCD18 was decreased in SKG mice 6 weeks after arthritis induction compared with healthy littermates. The sCD18 levels in both SKG and CIA mice exhibited a biphasic course after arthritis induction with an initial increase above baseline followed by a decline. Shedding of CD18 from RA SFMC and RA PBMC cultures was increased by TNFα and decreased by adalimumab.

Conclusions

The plasma sCD18 levels were altered in patients with RA, in mice with autoimmune arthritis and in cell cultures treated with TNFα and adalimumab. Decreased levels of plasma sCD18 could reflect autoimmunity in transition from early to chronic disease and normalization in response to treatment could reflect autoimmunity in remission.     

Elevated Soluble CD163 Plasma Levels Are Associated with Disease Severity in Patients with Hemorrhagic Fever with Renal Syndrome

Background

Hantaan virus is a major zoonotic pathogen that causesing hemorrhagic fever with renal syndrome (HFRS). Although HFRS pathogenesis has not been entirely elucidated, the importance of host-related immune responses in HFRS pathogenesis has been widely recognized. CD163, a monocyte and macrophage-specific scavenger receptor that plays a vital function in the hosts can reduce inflammation, is shed during activation as soluble CD163 (sCD163). The aim of this study was to investigate the pathological significance of sCD163 in patients with HFRS.

Methods

Blood samples were collected from 81 hospitalized patients in Tangdu Hospital from October 2011 to January 2014 and from 15 healthy controls. The sCD163 plasma levels were measured using a sandwich ELISA, and the relationship between sCD163 and disease severity was analyzed. Furthermore, CD163 expression in 3 monocytes subset was analyzed by flow cytometry.

Results

The results demonstrated that sCD163 plasma levels during the HFRS acute phase were significantly higher in patients than during the convalescent stage and the levels in the healthy controls (P<0.0001). The sCD163 plasma levels in the severe/critical group were higher than those in the mild/moderate group during the acute (P<0.0001). A Spearman correlation analysis indicated that the sCD163 levels were positively correlated with white blood cell, serum creatine, blood urea nitrogen levels, while they were negatively correlated with blood platelet levels in the HFRS patients. The monocyte subsets were significantly altered during the acute stage. Though the CD163 expression levels within the monocyte subsets were increased during the acute stage, the highest CD163 expression level was observed in the CD14++CD16+ monocytes when compared with the other monocyte subsets.

Conclusion

sCD163 may be correlated with disease severity and the disease progression in HFRS patients; however, the underlying mechanisms should be explored further.     

Nevirapine,Sodium Concentration and HIV-1 RNA in Breast Milk and Plasma among HIV-Infected Women Receiving Short-Course Antiretroviral Prophylaxis

Introduction

Risk factors for breast milk transmission of HIV-1 from mother to child include high plasma and breast milk viral load, low maternal CD4 count and breast pathology such as mastitis.

Objective

To determine the impact of nevirapine and subclinical mastitis on HIV-1 RNA in maternal plasma and breast milk after intrapartum single-dose nevirapine combined with either 1-week tail of Combivir (zidovudine/lamivudine) or single-dose Truvada (tenofovir/emtricitabine).

Methods

Maternal plasma and bilateral breast milk samples were collected between April 2008 and April 2011 at 1, 4 and 6 weeks postpartum from HIV-infected Tanzanian women. Moreover, plasma samples were collected at delivery from mother and infant.

Results

HIV-1 RNA was quantified in 1,212 breast milk samples from 273 women. At delivery, 96% of the women and 99% of the infants had detectable nevirapine in plasma with a median (interquartile range, IQR) of 1.5 μg/mL (0.75–2.20 μg/mL) and 1.04 μg/mL (0.39–1.71 μg/mL), respectively (P < 0.001). At 1 week postpartum, 93% and 98% of the women had detectable nevirapine in plasma and breast milk, with a median (IQR) of 0.13 μg/mL (0.13–0.39 μg/mL) and 0.22 μg/mL (0.13–0.34 μg/mL), respectively. Maternal plasma and breast milk HIV-1 RNA correlated at all visits (R = 0.48, R = 0.7, R = 0.59; all P = 0.01). Subclinical mastitis was detected in 67% of the women at some time during 6 weeks, and in 38% of the breast milk samples. Breast milk samples with subclinical mastitis had significantly higher HIV-1 RNA at 1, 4 and 6 weeks (all P < 0.05).

Conclusion

After short-course antiretroviral prophylaxis, nevirapine was detectable in most infant cord blood samples and the concentration in maternal plasma and breast milk was high through week 1 accompanied by suppressed HIV-1 RNA in plasma and breast milk.     

Low Levels of Microbial Translocation Marker LBP Are Associated with Sustained Viral Response after Anti-HCV Treatment in HIV-1/HCV Co-Infected Patients

Background

Microbial translocation (MT) contributes to immune activation during HIV and HCV infections. We investigated the kinetics of MT markers during anti-HCV and anti-HIV treatments, and if baseline plasma levels of lipopolysaccharide (LPS), lipopolysaccharide binding protein (LBP) and soluble CD14 (sCD14) could predict anti-HCV treatment outcome.

Methods

Plasma from 78 HIV-infected patients was evaluated for LPS, LBP and sCD14. The patients starting anti-HCV treatment (with ongoing antiretroviral (ART) treatment) were categorized into sustained viral responders (SVR; n = 21) or non-responders (NR; n = 15) based on treatment outcome. ART starting subjects—were categorized into chronically HCV-infected (CH; n = 24) and mono-infected (HIV; n = 18), based on the HCV infection status. Samples were collected before start (at baseline) of pegylated-interferon-alpha/ribavirin (peg-IFN/RBV) or antiretroviral-therapy and two years after treatment start (at follow up). χ²–test, non-parametric statistics and logistic regression were applied to determine the associations with treatment response and changes of the soluble markers.

Results

Plasma levels of LPS and sCD14 were elevated in all subjects before antiviral-treatment but remained unchanged at follow-up. Elevated levels of LBP were present in patients with HIV and HIV/HCV co-infection and were reduced by ART. Additionally, higher levels of LBP were present at baseline in NR vs. SVR. Higher levels of LBP at baseline were associated with non-response to peg-IFN/RBV treatment in both bivariate (OR: 0.19 95% CI: 0.06–0.31, p = 0.004) and multivariate analysis (OR: 1.43, 95% CI: 1.1–1.86, p = 0.07).

Conclusion

In HIV/HCV co-infected patients high baseline LBP levels are associated with non-response to peg-IFN/RBV therapy. Plasma LBP (decreased by ART) may be a more relevant MT marker than LPS and sCD14.     

Comparative Assessment of Cytokines and Other Inflammatory Markers for the Early Diagnosis of Neonatal Sepsis–A Case Control Study

Objective

Cytokines (IL-6, IL-8 and TNF-α), sCD163, and C-reactive protein were serially measured in an attempt to identify a set of tests which can reliably confirm or refute the diagnosis of neonatal sepsis at an early stage.

Methods

One hundred neonates suspected to have sepsis on clinical grounds and who met the inclusion criteria were enrolled for the study. Based on the positive or negative blood culture reports they were classified as infected (n = 50) and non-infected (n = 50) neonates respectively. Fifty healthy neonates without any signs of sepsis were also included in the study as control group. The initial blood sample was taken on day 0 (at the time of sepsis evaluation) and two further samples were taken on days 1 and 2 for monitoring the clinical progress and response to treatment. In the control group the cord blood and 48 hours venous sample was collected. Plasma CRP (ng/ml), IL-6 (pg/ml), IL-8 (pg/ml), TNF-α (ng/ml) and sCD163 (ng/ml) were determined by double antibody method Enzyme Linked Immunosorbent Assay in all the three blood samples.

Results

The cut of levels for CRP at >19,689 ng/ml had a sensitivity of 68%, specificity of 92%, for IL-6 at >95.32 pg/ml had a sensitivity of 54%, specificity of 96%, for IL-8 at >70.86 pg/ml had a sensitivity of 78%, specificity of 70%, for sCD163 at >896.78 ng/ml had a sensitivity of 100%, specificity of 88% for the diagnosis of infection before antibiotics. TNF-α levels of >12.6 ng/ml showed 100% sensitivity and 72% specificity for the diagnosis of inflammation.

Conclusion

The most powerful predictor to differentiate between the non-infected and infected neonates before antibiotics was sCD163. The most powerful indicator for evaluation of prognosis is IL-6. sCD163 can be used alone to screen for sepsis in neonates before the results of blood culture are received.     

Elevated Membrane and Soluble CD64: A Novel Marker Reflecting Altered FcγR Function and Disease in Early Rheumatoid Arthritis That Can Be Regulated by Anti-Rheumatic Treatment

Objectives

Fc receptors (FcR) interacting with immune complexes (ICs) is a central event in the immune pathogenesis of rheumatoid arthritis (RA). Here we asked if a specific FcR is linked to RA pathogenesis and if FcR activities relate to disease and treatment outcome in early RA.

Material and Methods

Twenty autoantibody-positive RA patients and 33 HC were included. The patients were evaluated before and after treatment with methotrexate and prednisolone. At follow-up, the EULAR response criteria were applied to determine the individual treatment outcomes. Serum immunoglobulin levels were measured and the expression of FcR for IgG (FcγR) and IgA (FcαR) on peripheral blood monocytes were determined by flow cytometry. The monocytic FcγR function was evaluated by human IgG1 and IgG3 IC-binding and TNFα stimulated release. Plasma levels of soluble FcRs (sFcRs) were determined with ELISA.

Results

The IgG1 and IgG3 levels were elevated in the RA sera. The RA monocytes expressed more CD64 and cell surface-bound IgG than HC monocytes, and showed an impaired FcγR function as reflected by changes in IC-binding and decreased IC-stimulated TNFα secretion. These findings correlated significantly with different disease activity markers. Furthermore, sFcRs were elevated in the patient plasma, and sCD64 was specific for RA (compared with a reference group of patients with active psoriatic arthritis). Following treatment, immunoglobulins and sFcR levels were reduced, whereas membrane CD64 was only decreased in patients with good response to treatment.

Conclusions

Early RA patients display increased membrane and soluble CD64 and an impaired FcγR function correlating with joint disease activity. Beneficial responses of anti-rheumatic treatment in patients reduce CD64. These data suggest sCD64 as an important objective biomarker in RA.     

Hierarchy Low CD4+/CD8+ T-Cell Counts and IFN-γ Responses in HIV-1+ Individuals Correlate with Active TB and/or M.tb Co-Infection

Objective

Detailed studies of correlation between HIV-M.tb co-infection and hierarchy declines of CD8+/CD4+ T-cell counts and IFN-γ responses have not been done. We conducted case-control studies to address this issue.

Methods

164 HIV-1-infected individuals comprised of HIV-1⁺ATB, HIV-1⁺LTB and HIV-1⁺TB^- groups were evaluated. Immune phenotyping and complete blood count (CBC) were employed to measure CD4+ and CD8+ T-cell counts; T.SPOT.TB and intracellular cytokine staining (ICS) were utilized to detect ESAT6, CFP10 or PPD-specific IFN-γ responses.

Results

There were significant differences in median CD4+ T-cell counts between HIV-1⁺ATB (164/μL), HIV-1⁺LTB (447/μL) and HIV-1⁺TB^- (329/μL) groups. Hierarchy low CD4+ T-cell counts (<200/μL, 200-500/μL, >500/μL) were correlated significantly with active TB but not M.tb co-infection. Interestingly, hierarchy low CD8+ T-cell counts were not only associated significantly with active TB but also with M.tb co-infection (P<0.001). Immunologically, HIV-1⁺ATB group showed significantly lower numbers of ESAT-6-/CFP-10-specific IFN-γ+ T cells than HIV-1⁺LTB group. Consistently, PPD-specific IFN-γ+CD4+/CD8+ T effector cells in HIV-1⁺ATB group were significantly lower than those in HIV-1⁺LTB group (P<0.001).

Conclusions

Hierarchy low CD8+ T-cell counts and effector function in HIV-1-infected individuals are correlated with both M.tb co-infection and active TB. Hierarchy low CD4+ T-cell counts and Th1 effector function in HIV-1+ individuals are associated with increased frequencies of active TB, but not M.tb co-infection.     

Plasma Levels of Neopterin and C-Reactive Protein (CRP) in Tuberculosis (TB) with and without HIV Coinfection in Relation to CD4 Cell Count

Background

While the risk of TB is elevated in HIV-positive subjects with low CD4 cell counts, TB may in itself be associated with CD4 lymphocytopenia. We investigated markers of immune activation (neopterin) and inflammation (CRP) in TB patients with and without HIV coinfection and their association with CD4 cell levels, and determined their predictive capacity as alternative markers of advanced immunosuppression.

Methods

Participants selected from a cohort of adults with TB at Ethiopian health centers (195 HIV+/TB+, 170 HIV-/TB+) and 31 controls were tested for plasma levels of neopterin and CRP. Baseline levels of neopterin and CRP were correlated to CD4 cell count before and after anti-TB treatment (ATT). The performance to predict CD4 cell strata for both markers were investigated using receiver operating curves.

Results

Levels of both biomarkers were elevated in TB patients (neopterin: HIV+/TB+ 54 nmol/l, HIV-/TB+ 23 nmol/l, controls 3.8 nmol/l; CRP: HIV+/TB+ 36 μg/ml, HIV-/TB+ 33 μg/ml, controls 0.5 μg/ml). Neopterin levels were inversely correlated (-0.53, p<0.001) to CD4 cell count, whereas this correlation was weaker for CRP (-0.25, p<0.001). Neither of the markers had adequate predictive value for identification of subjects with CD4 cell count <100 cells/mm³ (area under the curve [AUC] 0.64 for neopterin, AUC 0.59 for CRP).

Conclusion

Neopterin levels were high in adults with TB, both with and without HIV coinfection, with inverse correlation to CD4 cell count. This suggests that immune activation may be involved in TB-related CD4 lymphocytopenia. However, neither neopterin nor CRP showed promise as alternative tests for immunosuppression in patients coinfected with HIV and TB.     

TNF-Like Weak Inducer of Apoptosis (TWEAK) Promotes Beta Cell Neogenesis from Pancreatic Ductal Epithelium in Adult Mice

Aim/Hypothesis

The adult mammalian pancreas has limited ability to regenerate in order to restore adequate insulin production from multipotent progenitors, the identity and function of which remain poorly understood. Here we test whether the TNF family member TWEAK (TNF-like weak inducer of apoptosis) promotes β-cell neogenesis from proliferating pancreatic ductal epithelium in adult mice.

Methods

C57Bl/6J mice were treated with Fc-TWEAK and pancreas harvested at different time points for analysis by histology and immunohistochemistry. For lineage tracing, 4 week old double transgenic mice CAII-CreER^TM: R26R-eYFP were implanted with tamoxifen pellet, injected with Fc-TWEAK or control Ig twice weekly and analyzed at day 18 for TWEAK-induced duct cell progeny by costaining for insulin and YFP. The effect of TWEAK on pancreatic regeneration was determined by pancytokeratin immunostaining of paraffin embedded sections from wildtype and TWEAK receptor (Fn14) deficient mice after Px.

Results

TWEAK stimulates proliferation of ductal epithelial cells through its receptor Fn14, while it has no mitogenic effect on pancreatic α- or β-cells or acinar cells. Importantly, TWEAK induces transient expression of endogenous Ngn3, a master regulator of endocrine cell development, and induces focal ductal structures with characteristics of regeneration foci. In addition, we identify by lineage tracing TWEAK-induced pancreatic β-cells derived from pancreatic duct epithelial cells. Conversely, we show that Fn14 deficiency delays formation of regenerating foci after Px and limits their expansion.

Conclusions/Interpretation

We conclude that TWEAK is a novel factor mediating pancreatic β-cell neogenesis from ductal epithelium in normal adult mice.     

Neuropeptide Y and α-MSH Circadian Levels in Two Populations with Low Body Weight: Anorexia Nervosa and Constitutional Thinness

Context

Anorexia nervosa (AN) presents an adaptive appetite regulating profile including high levels of ghrelin and 26RFa (orexigenic) and low levels of leptin and PYY (anorexigenic). However, this adaptive mechanism is not effective in promoting food intake. The NPY/proopiomelanocortin (POMC) system plays a crucial role in the regulation of feeding behavior as NPY is the most potent orexigenic neuropeptide identified so far and as the POMC-derived peptide α-MSH drastically reduces food intake, and this peptidergic system has not been thoroughly studied in AN.

Objective

The aim of the present study was thus to investigate whether a dysfunction of the NPY/POMC occurs in two populations with low body weight, AN and constitutional thinness (CT).

Design and Settings

This was a cross-sectional study performed in an endocrinological unit and in an academic laboratory.

Investigated Subjects

Three groups of age-matched young women were studied: 23 with AN (AN), 22 CT and 14 normal weight controls.

Main Outcome Measures

Twelve-point circadian profiles of plasma NPY and α-MSH levels were measured in the three groups of investigated subjects.

Results

No significant circadian variation of NPY was detected between the three groups. Plasma α-MSH levels were significantly lower in AN (vs controls) all over the day. The CT group, compared to controls, presented lower levels of α-MSH in the morning and the evening, and an important rise during lunchtime.

Conclusion

In AN patients, the NPY system is not up-regulated under chronic undernutrition suggesting that this may play a role in the inability of anorectic women to adapt food intake to their energy demand. In contrast, low circadian α-MSH levels integrate the adaptive profile of appetite regulation of this disease. Finally, in CT women, the important α-MSH peak detected during lunchtime could explain why these patients are rapidly food satisfied.     

Asymptomatic Helminth Infection in Active Tuberculosis Is Associated with Increased Regulatory and Th-2 Responses and a Lower Sputum Smear Positivity

Background

The impact of intestinal helminth infection on the clinical presentation and immune response during active tuberculosis (TB) infection is not well characterized. Our aim was to investigate whether asymptomatic intestinal helminth infection alters the clinical signs and symptoms as well as the cell mediated immune responses in patients with active TB.

Methodology

Consecutive, newly diagnosed TB patients and healthy community controls (CCs) were recruited in North-west Ethiopia. TB-score, body mass index and stool samples were analyzed. Cells from HIV-negative TB patients (HIV-/TB) and from CCs were analyzed for regulatory T-cells (Tregs) and cytokine responses using flow cytometry and ELISPOT, respectively.

Results

A significantly higher ratio of helminth co-infection was observed in TB patients without HIV (Helm+/HIV-/TB) compared to HIV negative CCs, (40% (121/306) versus 28% (85/306), p = 0.003). Helm+/HIV-/TB patients showed significantly increased IL-5 secreting cells compared to Helm-/HIV-/TB (37 SFU (IQR:13–103) versus 2 SFU (1–50); p = 0.02, n = 30). Likewise, levels of absolute Tregs (9.4 (3.2–16.7) cells/μl versus 2.4 (1.1–4.0) cells/μl; p = 0.041) and IL-10 secreting cells (65 SFU (7–196) versus 1 SFU (0–31); p = 0.014) were significantly higher in Helm+/HIV-/TB patients compared to Helm-/HIV-/TB patients. In a multivariate analysis, a lower rate of sputum smear positivity for acid fast bacilli, lower body temperature, and eosinophilia were independently associated with helminth infection in TB patients.

Conclusions

Asymptomatic helminth infection is associated with increased regulatory T-cell and Th2-type responses and a lower rate of sputum smear positivity. Further studies are warranted to investigate the clinical and immunological impact of helminth infection in TB patients.     

Elevated Plasma Soluble CD14 and Skewed CD16+ Monocyte Distribution Persist despite Normalisation of Soluble CD163 and CXCL10 by Effective HIV Therapy: A Changing Paradigm for Routine HIV Laboratory Monitoring?

Objective

We investigated plasma and flow cytometric biomarkers of monocyte status that have been associated with prognostic utility in HIV infection and other chronic inflammatory diseases, comparing 81 HIV⁺ individuals with a range of treatment outcomes to a group of 21 healthy control blood donors. Our aim is to develop and optimise monocyte assays that combine biological relevance, clinical utility, and ease of adoption into routine HIV laboratory practice.

Design

Cross-sectional evaluation of concurrent plasma and whole blood samples.

Methods

A flow cytometry protocol was developed comprising single-tube CD45, CD14, CD16, CD64, CD163, CD143 analysis with appropriately matched isotype controls. Plasma levels of soluble CD14 (sCD14), soluble CD163 (sCD163) and CXCL10 were measured by ELISA.

Results

HIV status was associated with significantly increased expression of CD64, CD143 and CD163 on CD16⁺ monocytes, irrespective of the virological response to HIV therapy. Plasma levels of sCD14, sCD163 and CXCL10 were also significantly elevated in association with viremic HIV infection. Plasma sCD163 and CXCL10 levels were restored to healthy control levels by effective antiretroviral therapy while sCD14 levels remained elevated despite virological suppression (p<0.001).

Conclusions

Flow cytometric and plasma biomarkers of monocyte activation indicate an ongoing systemic inflammatory response to HIV infection, characterised by persistent alterations of CD16⁺ monocyte expression profiles and elevated sCD14 levels, that are not corrected by antiretroviral therapy and likely to be prognostically significant. In contrast, sCD163 and CXCL10 levels declined on antiretroviral therapy, suggesting multiple activation pathways revealed by these biomarkers. Incorporation of these assays into routine clinical care is feasible and warrants further consideration, particularly in light of emerging therapeutic strategies that specifically target innate immune activation in HIV infection.     

Routine Eye Screening by an Ophthalmologist Is Clinically Useful for HIV-1-Infected Patients with CD4 Count Less than 200 /μL

Objective

To investigate whether routine eye screening by an ophthalmologist in patients with HIV-1 infection is clinically useful.

Methods

A single-center, retrospective study in Tokyo, Japan. HIV-1-infected patients aged over 17 years who visited our clinic for the first time between January 2004 and December 2013 and underwent full ophthalmologic examination were enrolled. At our clinic, ophthalmologic examination, including dilated retinal examination by indirect ophthalmoscopy was routinely conducted by ophthalmologists on the first visit. The prevalence of ophthalmologic diseases and associated factors including the existence of ocular symptoms were analyzed.

Results

Of the 1,515 study patients, cytomegalovirus retinitis (CMV-R) was diagnosed in 24 (2%) patients, HIV retinopathy (HIV-R) in 127 (8%), cataract in 31 (2%), ocular syphilis in 4 (0.3%), and uveitis with unknown cause in 8 (0.5%). Other ocular diseases were diagnosed in 14 patients. The CD4 count was <200 /μL in all CMV-R cases and 87% of HIV-R. The prevalence of any ocular diseases, CMV-R, and HIV-R in patients with CD4 <200 /μL were 22%, 3%, and 15%, respectively, whereas for those with CD4 ≥200 /μL were 5%, 0%, and 2%, respectively. No ocular symptoms were reported by 71% of CMV-R cases and 82% of patients with any ocular diseases.

Conclusions

Routine ophthalmologic screening is recommended for HIV-1-infected patients with CD4 <200 /μL in resource-rich settings based on the high prevalence of ocular diseases within this CD4 count category and because most patients with ocular diseases, including those with CMV-R, were free of ocular symptoms.