Circulating Mitochondrial DNA Is Associated With High Levels of Fatigue in Two Independent Sarcoidosis Cohorts

BACKGROUND

Patients with sarcoidosis who develop severe clinical phenotypes of pulmonary fibrosis or multiorgan disease experience debilitating symptoms, with fatigue being a common chief complaint. Studies that have investigated this patient-related outcome measure (PROM) have used the Fatigue Assessment Scale (FAS), a self-reported questionnaire that reflects mental and physical domains. Despite extensive work, its cause is unknown and treatment options remain limited. Previously, we showed that the plasma of patients with sarcoidosis with extrapulmonary disease endorsing fatigue was enriched for mitochondrial DNA (mtDNA), a ligand for the innate immune receptor toll-like receptor 9 (TLR9). Through our cross-disciplinary platform, we investigated a relationship between sarcoidosis-induced fatigue and circulating mtDNA.

RESEARCH QUESTION

Is there a psychobiologic mechanism that connects sarcoidosis-induced fatigue and mtDNA-mediated TLR9 activation?

STUDY DESIGN AND METHODS

Using a local cohort of patients at Yale (discovery cohort) and the National Institutes of Health-sponsored Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis study (validation cohort), we scored the FAS and quantified in the plasma, mtDNA concentrations, TLR9 activation, and cytokine levels.

RESULTS

Although FAS scores were independent of corticosteroid use and Scadding stage, we observed a robust association between FAS scores, which included mental and physical domains, and multiorgan sarcoidosis. Subsequently, we identified a significant correlation between plasma mtDNA concentrations and all domains of fatigue. Additionally, we found that TLR9 activation is associated with all aspects of the FAS and partially mediates this PROM through mtDNA. Last, we found that TLR9-associated soluble mediators in the plasma are independent of all facets of fatigue.

INTERPRETATION

Through our cross-disciplinary translational platform, we identified a previously unrecognized psychobiologic connection between sarcoidosis-induced fatigue and circulating mtDNA concentrations. Mechanistic work that investigates the contribution of mtDNA-mediated innate immune activation in this PROM and clinical studies with prospective cohorts has the potential to catalyze novel therapeutic strategies for this patient population and those with similar conditions.

Effect of Papaya Leaves (<i>Carica papaya</i> L.) Extract on Immune Response (TLR-7, TLR-9) and Inflammation (COX-2) in Rats Induces DMBA (7,12-Dimethylbenz[a]antrasen)

BACKGROUND AND OBJECTIVE

TLR is known to regulate the immune system in cancer. TLR-7 and TLR-9 can enhance the antitumor immune system in many types of solid tumors. Cyclooxygenase-2 (COX-2) is a biomarker of inflammation. This study aimed to investigate the effect of papaya leaves extract on immune response (TLR 7, TLR 9) and inflammation (COX-2) in rats induced DMBA.

MATERIALS AND METHODS

This experimental study used Sprague dawley female rats of age more less 50 days. Rats were divided into 4 groups: Negative Control (NC), Positive Control (PC), Cancer Drug Doxorubicin (DOXO) and Papaya Leaves Extract (PLE). The study was conducted for 13 weeks. DMBA induction performed for 5 weeks with administration of 2 times per week.

RESULTS

the expression of TLR-7 of PLE and DOXO was higher than PC groups significantly different (p<0.05). The expression of TLR-9 of PLE was higher than NC, PC and DOXO groups but not significantly different (p>0.05) while the expression of COX-2 of PLE and DOXO groups was lower than NC and PC groups but not significantly different (p>0.05).

CONCLUSION

It can be concluded that papaya leaves extract can improve the immune system and reduce inflammation. It shows that papaya leaves extract has potent as anti-cancer.

Characterization of Intact Proviruses in Blood and Lymph Node from HIV-Infected Individuals Undergoing Analytical Treatment Interruption

The role of lymphoid tissue as a potential source of HIV-1 rebound following interruption of antiretroviral therapy (ART) is uncertain. To address this issue, we compared the latent viruses obtained from CD4+ T cells in peripheral blood and lymph nodes to viruses emerging during treatment interruption. Latent viruses were characterized by sequencing near-full-length (NFL) proviral DNA and env from viral outgrowth assays (VOAs). Five HIV-1-infected individuals on ART were studied, four of whom participated in a clinical trial of a TLR9 agonist that included an analytical treatment interruption. We found that 98% of intact or replication-competent clonal sequences overlapped between blood and lymph node. In contrast, there was no overlap between 205 latent reservoir and 125 rebound sequences in the four individuals who underwent treatment interruption. However, rebound viruses could be accounted for by recombination. The data suggest that CD4+ T cells carrying latent viruses circulate between blood and lymphoid tissues in individuals on ART and support the idea that recombination may play a role in the emergence of rebound viremia.IMPORTANCE HIV-1 persists as a latent infection in CD4+ T cells that can be found in lymphoid tissues in infected individuals during ART. However, the importance of this tissue reservoir and its contribution to viral rebound upon ART interruption are not clear. In this study, we sought to compare latent HIV-1 from blood and lymph node CD4+ T cells from five HIV-1-infected individuals. Further, we analyzed the contribution of lymph node viruses to viral rebound. We observed that the frequencies of intact proviruses were the same in blood and lymph node. Moreover, expanded clones of T cells bearing identical proviruses were found in blood and lymph node. These latent reservoir sequences did not appear to be the direct origin of rebound virus. Instead, latent proviruses were found to contribute to the rebound compartment by recombination.

Rapid Complexation of Aptamers by Their Specific Antidotes

Nucleic acid ligands, aptamers, harbor the unique characteristics of small molecules and antibodies. The specificity and high affinity of aptamers enable their binding to different targets, such as small molecules, proteins, or cells. Chemical modifications of aptamers allow increased bioavailability. A further great benefit of aptamers is the antidote (AD)-mediated controllability of their effect. In this study, the AD-mediated complexation and neutralization of the thrombin binding aptamer NU172 and Toll-like receptor 9 (TLR9) binding R10-60 aptamer were determined. Thereby, the required time for the generation of aptamer/AD-complexes was analyzed at 37 °C in human serum using gel electrophoresis. Afterwards, the blocking of aptamers’ effects was analyzed by determining the activated clotting time (ACT) in the case of the NU172 aptamer, or the expression of immune activation related genes IFN-1β, IL-6, CXCL-10, and IL-1β in the case of the R10-60 aptamer. Gel electrophoresis analyses demonstrated the rapid complexation of the NU172 and R10-60 aptamers by complementary AD binding after just 2 min of incubation in human serum. A rapid neutralization of anticoagulant activity of NU172 was also demonstrated in fresh human whole blood 5 min after addition of AD. Furthermore, the TLR9-mediated activation of PMDC05 cells was interrupted after the addition of the R10-60 AD. Using these two different aptamers, the rapid antagonizability of the aptamers was demonstrated in different environments; whole blood containing numerous proteins, cells, and different small molecules, serum, or cell culture media. Thus, nucleic acid ADs are promising molecules, which offer several possibilities for different in vivo applications, such as antagonizing aptamer-based drugs, immobilization, or delivery of oligonucleotides to defined locations.

Evaluation of PBMC Distribution and TLR9 Expression in Patients with Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease which results in damage to various organs. Some animal studies have revealed that activation of Toll-like receptors (TLRs) is important in the pathogenesis of SLE. In the present study, the percentage of different immune cell subsets in 35 SLE patients and 38 control subjects was analyzed by flow cytometry. We also assessed the expression of TLR9 in the population of peripheral blood mononuclear cells (PBMCs) including T lymphocytes (CD4+ and CD8+), B lymphocytes (CD19+), NK cells (CD56+) and monocytes (CD14+) in SLE patients and healthy controls. The results showed that the percentage of CD8+ T lymphocytes and CD14+ monocytes were significantly higher (p˂0.001) in the SLE patients than the healthy control subjects. Moreover, the percentage of CD56+ NK cells were significantly lower in the SLE patients than the healthy control subjects (p=0.001). The findings indicated that the expression of TLR9 was significantly higher in CD4+ and CD8+ T lymphocytes and CD19+ B lymphocytes of SLE patients than in control subjects (all p˂0.05). The difference in TLR9 expression are involved in pathogenesis of the SLE, hence it can be used as an indicator for SLE diagnosis.

[TLR9 expression is positively correlated with the levels of CD38, HLA-DR and CD95 on peripheral blood mononuclear cells in chronic HBV infected patients]

OBJECTIVE

To explore the relationship between the expression of TLR9 and the levels of CD38, HLA-DR and CD95 on peripheral blood mononuclear cells (PBMCs) of chronic hepatitis B virus (HBV) infected patients.

METHODS

70 chronic HBV infected patients and 12 healthy donors were enrolled in this study, and density gradient centrifugation was used to isolate PBMCs from peripheral blood with EDTA for anticoagulation. Flow cytometry was used to detect the levels of TLR9, CD38, HLA-DR and CD95 on PBMCs.

RESULTS

Compared to the healthy donors, chronic HBV infected patients with low viral load or high viral load had significantly higher levels of TLR9, HLA-DR and CD95 on PMBCs. Furthermore, the co-expression rates of TLR9 and CD38, HLA-DR, CD95 on PBMCs were obviously higher than those of the healthy donors. Correlation analysis showed that the expression of TLR9 was positively correlated with CD38 (r=0.345), HLA-DR (r=0.334), CD95 (r=0.227) on PBMCs in the patients with chronic HBV infection.

CONCLUSION

The expression of TLR9 increased and was positively associated with CD38, HLA-DR and CD95 on PBMCs during chronic HBV infection.

Correlation of serum toll like receptor 9 and trace elements with lipid peroxidation in the patients of breast diseases

Toll-like receptors are recognized as redox sensitive receptor proteins and have been implicated in cellular response to oxidative stress. Altered pro-oxidant-antioxidant balance leads to an increased oxidative damage and consequently play an important role in breast diseases. The study was designed to access the oxidative stress status by quantification of byproducts generated during lipid peroxidation and inadequate trace elements during oxidative damage and its effects on the toll like receptor (TLR) activity in patients of breast diseases. Decreased levels of selenium, copper, zinc, magnesium and iron with elevated levels of malondialdehyde (marker of lipid peroxidation) were accompanied by decreased TLR activity in patients of benign breast diseases as well as breast carcinoma. A similar pattern was observed with the advancement of disease and its subsequent progression in breast carcinoma patients. Results of multinomial regression analysis suggest benign breast disease patients are at higher risk of developing breast cancer with high odds ratio of lipid damage.

The expression of TLR-9, CD86, and CD95 phenotypes in circulating B cells of patients with chronic viral hepatitis B or C before and after antiviral therapy

AIMS

This study aimed to assess the differential expression of specific B cell subtypes in patients with chronic viral hepatitis.

METHODS

The frequencies of differential expression of specific B cell subtypes in patients with chronic viral hepatitis and healthy controls were assessed by flow cytometry using monoclonal antibodies specific for CD38, CD27, CD86, CD95, TLR-9, and IgD. The effect of adefovir treatment on B cell subsets in HBV patients was determined. The values of clinical parameters in the patients were also measured.

RESULTS

The frequency of CD86+ B cells was not significantly different in chronic HBV patients but was higher in HCV patients compared with that in healthy controls. CD95 and IgD levels were lower in HBV and HCV patients than in healthy controls. A significant negative correlation occurred between the proportion of CD95+ B cells and HBV DNA viral load. The frequency of TLR-9 on the B cells in HBV and HCV patients was higher compared with that of healthy controls. After treatment with adefovir, the frequency of CD95 and IgD expressed on B cells was increased in HBV patients.

CONCLUSIONS

Activated B cells and exhausted B cells homeostasis were commonly disturbed in HBV and HCV patients.

Interleukin-21 is increased in active systemic lupus erythematosus patients and contributes to the generation of plasma B cells

OBJECTIVES

Excessive interleukin- (IL-) 21 production by T cells has been implicated in the pathogenesis of systemic lupus erythematosus (SLE). We explored the expression and function of IL-21 in human SLE.

METHODS

IL-21 and IL-21 receptor (IL-21R) expression was assessed by real-time PCR and flow cytometry in peripheral blood mononuclear cells (PBMCs) of SLE patients and healthy controls. PBMCs, purified CD19+CD27- naïve and CD19+CD27+ memory B cells were stimulated with IL-21 and CpG-ODN2006 (TLR-9 agonist) to examine generation of memory and plasma (CD19+CD38highIgD-) B cells. Apoptosis was assessed by 7AAD staining.

RESULTS

Active SLE patients had 4-fold higher IL-21 mRNA and increased levels of intracellular IL-21 in peripheral blood CD4+ T cells (mean±SD fluorescence intensity, 1.7±0.1 in active versus 0.9±0.3 in inactive SLE and controls, p=0.035). IL-21R mRNA was comparable between SLE and healthy controls. Stimulation of PBMCs with IL-21 increased the proportion of memory and plasma cells; addition of CpG-ODN2006 enhanced these effects. Both naïve and memory B cells responded to IL-21/TLR-9 by increased generation of memory and plasma B cells, respectively; an anti-apoptotic effect was observed. In active SLE, PBMCs stimulation with IL-21 and/or CpG-ODN increased memory and plasma B cells, comparable to healthy controls. Addition of IL-21 to lupus autologous mixed lymphocyte cultures induced significant IgG production, and treatment with IL-21R.Fc to block IL-21/IL-21R interaction reduced the proportion of plasma cells.

CONCLUSIONS

Increased IL-21 may synergise with TLR-9 signalling and contributes to generation of plasma cells in active SLE patients.

[Expression of blood Toll-like receptors and cytokines in children with recurrent herpes simplex]

OBJECTIVE

This study examined the expression of Toll-like receptors (TLR) in peripheral blood mononuclear cells (PBMC) and serum levels of IL-6, IL-10 and TNF-alpha in children with recurrent herpes simplex, in order to investigate the role of TLR2 and TLR9 in recurrent herpes simplex.

METHODS

The expression of TLR2 and TLR9 in PBMC was examined by flow cytometer, and serum levels of IL-6, IL-10 and TNF-alpha were detected using ELISA in 22 children with recurrent herpes simplex and in 13 age-matched healthy volunteers.

RESULTS

The expression of both TLR2 and TLR9 obviously increased in children with recurrent herpes simplex compared with that in healthy controls (p<0.01). Serum levels of IL-6 and IL-10 increased, while serum TNF-alpha levels decreased significantly in children with recurrent herpes simplex compared with those in healthy controls (p<0.01). There were positive correlations between TLR2 and TLR9 expression and serum IL-6 and IL-10 levels in children with recurrent herpes simplex (p<0.01).

CONCLUSIONS

TLR2 and TLR9 in PBMC may participate in the recognition of herpes simplex virus and activate the signal pathway of TLR in children with recurrent herpes simplex. The production and release of IL-6 and IL-10 might be mediated by TLR2 and TLR9.

Toll-like receptor expression in lupus peripheral blood mononuclear cells

OBJECTIVE

To investigate expression of members of the Toll-like receptor (TLR) family in peripheral blood mononuclear cells (PBMC) in patients with systemic lupus erythematosus (SLE).

METHODS

We analyzed PBMC from 14 patients with SLE and 15 healthy subjects. The surface expressions of TLR2 and TLR4 and intracellular expression of TLR9 on PBMC were analyzed by flow cytometry.

RESULTS

Although TLR4 expressions on CD14+ monocytes were not significantly different between healthy subjects and patients with SLE, TLR2 expressions on monocytes were reduced in patients with SLE compared to healthy subjects. Intracellular TLR9 expression levels of CD19+ B lymphocytes were significantly elevated in patients with SLE. However, the TLR9 expression levels of plasmacytoid dendritic cells were not significantly different between these patients and healthy subjects.

CONCLUSION

Our results show that human peripheral blood B cells express TLR9 and that its expression is increased in patients with SLE. This upregulated expression of TLR9 in B cells may be related to the abnormal B cell hyperactivity in patients with SLE.

Altered Toll-like receptor 9 responses in circulating B cells at the onset of extensive chronic graft-versus-host disease

B cells appear to play a role in chronic graft-versus-host disease (cGVHD) as shown in murine models and the success of anti-CD20 B cell antibody treatment in humans. Recent studies have shown that immunostimulatory microbial CpG-DNA splenic responses were enhanced in murine GVHD. We hypothesized that CpG-induced B cell responses are increased in human cGVHD. Newly diagnosed cGVHD patients enrolled on the COG protocol ASCT0031 were divided into early (3-8 months postblood and marrow transplant [BMT]) and late (> or =9 months post-BMT) onset groups and compared to time-matched control BMT patients. A significantly greater percentage of phosphorothioate (PS)-modified CpG stimulated B cells from cGVHD patients demonstrated an increased expression of CD86 compared to controls (P = .0004). This response had a significant correlation between B cell TLR9 expression (r(2) = 0.65; P = .002) and CD86 upregulation using the entirely TLR9-dependent native phosphodiester CpG (P = .003). The PS-modified CpG response at 2 months after initiation of cGVHD therapy demonstrated a trend toward predicting therapeutic response at 9 months post-BMT (P = .07). These findings suggest that an increased number of B cells, primed for a TLR9 response, may play a role in the pathophysiology of cGVHD.