Combined Effect of HPV and Several Gene SNPs in Laryngeal Cancer.

Background and objectives: Laryngeal squamous cell carcinoma (LSCC) is one of the most common head and neck tumors. The molecular mechanism of LSCC remains unclear. The aim of this study was to evaluate the prevalence of Human papillomavirus (HPV) and single nucleotide polymorphisms (SNPs) of TP53, MDM2, MDM4, MTHFR, CASP8, and CCR5 genes in LSCC, and to assess their correlations with patient survival. Materials and Methods: 49 LSCC patients were enrolled in this study. PCR and qRT-PCR were used to detect, identify, and quantify HPV. SNPs were genotyped using PCR and PCR-RFLP. Results: By analyzing the interactions of the SNPs of the genes with clinical parameters, the majority of patients with lymph node status (N1,2) were identified as carriers of MDM2 T/G, CASP8 ins/del, CCR5 wt/wt SNP. Cluster analysis showed that patients with MDM2 T/T SNP survive longer than patients identified as CASP8 ins/ins, MTHFR C/C, and MDM4 A/A variant carriers; meanwhile, LSCC patients with MDM2 T/T polymorphic variant had the best survival. Multivariate analysis showed that HPV-positive patients without metastasis in regional lymph nodes (N0) and harboring CASP8 ins/del variant had the best survival. Meanwhile, HPV-negative patients with identified metastasis in lymph nodes (N1 and N2) and CASP8 ins/del variant had poor survival. Conclusions: This finding suggests patients survival prognosis and tumor behavior are different according HPV status, SNP variants, and clinical characteristics of the LSCC.

The Protective Role of Bacteroides fragilis in a Murine Model of Colitis-Associated Colorectal Cancer.

Many patients with chronic inflammation of the gut, such as that observed in inflammatory bowel disease (IBD), develop colorectal cancer (CRC). Recent studies have reported that the development of IBD and CRC partly results from an imbalanced composition of intestinal microbiota and that intestinal inflammation in these diseases can be modulated by the microbiota. The human commensal Bacteroides fragilis is best exemplified playing a protective role against the development of experimental colitis in several animal disease models. In this study, we found that gut inflammation caused by dextran sulfate sodium (DSS) treatment was inhibited by B. fragilis colonization in mice. Further, we reveal a protective role of B. fragilis treatment against colon tumorigenesis using an azoxymethane (AOM)/DSS-induced model of colitis-associated colon cancer in mice and demonstrate that the decreased tumorigenesis by B. fragilis administration is accompanied by inhibited expression of C-C chemokine receptor 5 (CCR5) in the gut. We show direct evidence that the inhibition of tumor formation provided by B. fragilis in colitis-associated CRC animals was dependent on the production of polysaccharide A (PSA) from B. fragilis and that Toll-like receptor 2 (TLR2) signaling was responsible for the protective function of B. fragilisIMPORTANCE The incidence of colorectal cancer (CRC) is rapidly growing worldwide, and there is therefore a greater emphasis on studies of the treatment or prevention of CRC pathogenesis. Recent studies suggested that consideration of the microbiota is unavoidable to understand inflammation and tumorigenesis in the gastrointestinal tract. We demonstrate, using a mouse model of colitis-associated CRC, that human commensal B. fragilis protects against colon tumorigenesis. The protective role against tumor formation provided by B. fragilis is associated with inhibition of expression of the chemokine receptor CCR5 in the colon. The molecular mechanism for protection against CRC provided by B. fragilis is dependent on polysaccharide A production and is mediated by TLR2 signaling. Our results suggest that the commensal microorganism B. fragilis can be used to prevent inflammation-associated CRC development and may provide an effective therapeutic strategy for CRC.

Transcriptional gene silencing limits CXCR4-associated depletion of bone marrow CD34+ cells in HIV-1 infection.

OBJECTIVES: Hematological abnormalities that include changes in bone marrow, such as in anemia and pancytopenia, are common among HIV-infected patients, particularly in the advanced stage of disease. Such abnormalities may be caused by a reduced bone marrow function for hematopoiesis. The aim of this study was to determine whether transcriptional gene silencing can help to preserve the hosts' hematopoietic potential in addition to peripheral CD4+ T cells against CCR5-tropic HIV infection. DESIGN: NOD/SCID/JAK3null (NOJ) mice were transplanted with human cord-derived CD34+ cells with or without transduction with a lentiviral vector expressing a promoter-targeting shRNA called PromA. METHODS: At 16 weeks after transplantation, mice engrafted with CD34+ cells were infected with CCR5-tropic HIV-1JRFL. RESULTS: At week 2 postinfection, HIV replication was observed in peripheral blood mononuclear cells and splenocytes. In mice transplanted with unmanipulated CD34+ cells, viral replication was accompanied by a loss of peripheral/spleen CD4+CCR5+ T cells. Interestingly, bone marrow CD34+ cells in HIV-infected mice were also depleted, but in a CXCR4-associated manner. Conversely, the lentiviral transfer of PromA in CD34+ cells prior to transplantation rendered the humanized NOJ mice resistant to HIV replication in CD4+ T cells, resulting in better preservation of peripheral/spleen CD4+CCR5+ T cells and bone marrow CD34+ cells at 2 weeks after infection. CONCLUSIONS: These results indicate that stable gene transfer of PromA to hematopoietic stem cells not only limited HIV replication but also led to preservation of different subsets of hematopoietic cells, including bone marrow stem/progenitor cells and CD4+ T cells.

Alterations of CCR5 and CCR7 expression on donor peripheral blood T cell subsets after mobilization with rhG-CSF correlate with acute graft-versus-host disease.

To investigate the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on chemokine receptors and explore the potential mechanism of rhG-CSF inducing immune tolerance, ninety-seven donor and recipient pairs undergoing family-donor allogeneic hematopoietic stem cell transplantation were studied. The results indicated that different donors showed great disparities in expression changes after mobilization. Multivariate analysis revealed that both HLA mismatching and CCR7 downregulation on donors' CD4+ T cells after mobilization were independent risk factors for acute graft-versus-host disease (GVHD). In contrast, CCR5 downregulation on CD4+ T cells was associated with reduced incidence of acute GVHD. In conclusion, rhG-CSF mobilization could lead to differential regulation of chemokine receptors expression on T cell subsets in different donors. Downregulation of CCR5 and upregulation of CCR7 expression on donor CD4+ T cells might protect recipients from acute GVHD. This finding may provide a promising new strategy for the prevention and treatment of acute GVHD.

T cells are involved in the induction of macrophage phenotypes in oral leukoplakia and squamous cell carcinoma-a preliminary report.

BACKGROUND: The prognosis of human malignancies has been shown to depend on immunological parameters, such as macrophage polarization (M1 and M2). In this study, we identify the phenotype of macrophages, and investigate an involvement of infiltrated T cells that participate in the polarization of macrophages, in oral leukoplakia (OLK), and oral squamous cell carcinoma (OSCC). METHODS: Immunohistochemical method was used to examine the number of CD68+ , CD163+ (M2), iNOS+ (M1) macrophages, and CD4+ , CD8+ , CCR4+ (Th2), CCR5+ (Th1) cells in 102 cases of OSCC: without metastases-OSCC M(-) (n = 54), and with metastases-OSCC M(+) (n = 48), 23 cases of OLK, and 18 control cases. RESULTS: The mean number of CD68+ , CD163+ , iNOS+ , CD4+ , CCR4+ , CCR5+ cells was significantly increased in OSCC M(+) group compared with OLK, OSCC M(-) and control group. We found positive correlations between the number of CD4+ T cells and CD163+ and iNOS+ macrophages as well as CCR4+ and CCR5+ cells in both OSCC groups. The mean number of CD8+ cells was significantly increased in OSCC M(-) and OLK compared with OSCC M(+) and control group. In OSCC M(+) and OSCC M(-) groups, a negative correlation between the number of CD8+ cells and CD163+ and iNOS+ macrophages was found. CONCLUSIONS: The number and co-localization of lymphocytes and macrophages in OLK and OSCC may indicate that infiltrating cells influence the early and subsequent stage of oral carcinogenesis.

Microparticles derived from obese adipose tissue elicit a pro-inflammatory phenotype of CD16+, CCR5+ and TLR8+ monocytes.

Macrophage infiltration into adipose tissue (AT) is a hallmark of the chronic inflammatory response in obesity and is supported by an intense monocyte migration towards AT. Although it has been detected an increased proportion of circulating CD16+ monocyte subsets in obese subjects, the mechanisms underlying this effect and the contribution of these cells to the inflamed profile of obese AT are still poorly understood. We investigated whether factors secreted by human obese omental AT could polarize monocytes to CD16+ enriched phenotype, and how these changes could modify their migratory capacity towards adipose tissue itself. We show that explants of human obese omental AT, obtained during bariatric surgery, released higher levels of MIP1-α, TNFα, leptin and also VEGF, together with increasing amounts of microparticles (MP), when compared to explants of lean subcutaneous AT. A higher content of circulating MP derived from preadipocytes and leukocytes was also detected in plasma of obese subjects. Conditioned media or MP released from obese omental AT increased CD16 and CCR5 expression on CD14+CD16- monocytes and augmented their migratory capacity towards the conditioned media from obese omental AT, itself. This effect was inhibited when MIP1-α was neutralized. Additionally, we demonstrate that MP derived from obese omental AT carry and transfer TLR8 to monocytes, thus triggering an increase in CD16 expression in those cells. Our data shows a positive feedback loop between blood monocytes and obese omental AT, which releases chemotactic mediators and TLR8-enriched MP, thus inducing an up-regulation of CD16+ monocytes, favoring leukocyte infiltration in the obese omental AT.

Effects of conventional CPB and mini-CPB on neutrophils CD162, CD166 and CD195 expression.

OBJECTIVE: Cardiac surgery is known to trigger a systemic inflammatory response. While the use of conventional cardiopulmonary bypass (CPB) results in profound inflammation, modified mini-CPB is considered less harmful. We evaluated the impact of cardiac surgery on the expression of CD162, CD166, CD195 molecules and their association with the type of CPB used. METHODS AND RESULTS: Twenty-four patients were enrolled in our study. Twelve of them were operated using conventional CPB while the other twelve patients underwent surgery with mini-CPB. Blood samples were analysed by flow cytometry. We observed a significant increase in median fluorescence intensity of CD162 and CD195 that peaked instantly after surgery and normalized to the baseline value on the 1st day post surgery, whereas CD166 was initially down-regulated and its median fluorescence intensity (MFI) value increased to the baseline in the next few days. CONCLUSION: We observed immediate changes in the expression of CD162, CD166, and CD195 molecules on the neutrophils after surgery in both study groups of patients. The intensity of the observed changes was significantly greater in the group of patients who underwent conventional CPB compared to patients who underwent mini-CPB cardiac surgery.

CD25+ FoxP3+ Memory CD4 T Cells Are Frequent Targets of HIV Infection In Vivo.

UNLABELLED: Interleukin 2 (IL-2) signaling through the IL-2 receptor alpha chain (CD25) facilitates HIV replication in vitro and facilitates homeostatic proliferation of CD25(+) FoxP3(+) CD4(+) T cells. CD25(+) FoxP3(+) CD4(+) T cells may therefore constitute a suitable subset for HIV infection and plasma virion production. CD25(+) FoxP3(+) CD4(+) T cell frequencies, absolute numbers, and the expression of CCR5 and cell cycle marker Ki67 were studied in peripheral blood from HIV(+) and HIV(-) study volunteers. Different memory CD4(+) T cell subsets were then sorted for quantification of cell-associated HIV DNA and phylogenetic analyses of the highly variable EnvV1V3 region in comparison to plasma-derived virus sequences. In HIV(+) subjects, 51% (median) of CD25(+) FoxP3(+) CD4(+) T cells expressed the HIV coreceptor CCR5. Very high frequencies of Ki67(+) cells were detected in CD25(+) FoxP3(+) memory CD4(+) T cells (median, 27.6%) in comparison to CD25(-) FoxP3(-) memory CD4(+) T cells (median, 4.1%; P < 0.0001). HIV DNA content was 15-fold higher in CD25(+) FoxP3(+) memory CD4(+) T cells than in CD25(-) FoxP3(-) T cells (P = 0.003). EnvV1V3 sequences derived from CD25(+) FoxP3(+) memory CD4(+) T cells did not preferentially cluster with plasma-derived sequences. Quasi-identical cell-plasma sequence pairs were rare, and their proportion decreased with the estimated HIV infection duration. These data suggest that specific cellular characteristics of CD25(+) FoxP3(+) memory CD4(+) T cells might facilitate efficient HIV infection in vivo and passage of HIV DNA to cell progeny in the absence of active viral replication. The contribution of this cell population to plasma virion production remains unclear. IMPORTANCE: Despite recent advances in the understanding of AIDS virus pathogenesis, which cell subsets support HIV infection and replication in vivo is incompletely understood. In vitro, the IL-2 signaling pathway and IL-2-dependent cell cycle induction are essential for HIV infection of stimulated T cells. CD25(+) FoxP3(+) memory CD4 T cells, often referred to as regulatory CD4 T cells, depend on IL-2 signaling for homeostatic proliferation in vivo Our results show that CD25(+) FoxP3(+) memory CD4(+) T cells often express the HIV coreceptor CCR5, are significantly more proliferative, and contain more HIV DNA than CD25(-) FoxP3(-) memory CD4 T cell subsets. The specific cellular characteristics of CD25(+) FoxP3(+) memory CD4(+) T cells probably facilitate efficient HIV infection in vivo and passage of HIV DNA to cell progeny in the absence of active viral replication. However, the contribution of this cell subset to plasma viremia remains unclear.

Characteristics of peripheral blood CD4+CD25+ regulatory T cells and related cytokines in severe atopic dermatitis.

Regulatory T cells (Tregs) have been suggested to play a role in the pathogenesis of atopic dermatitis (AD). However, alterations in the ability of Tregs remain to be determined. To investigate the expression of various surface receptors on CD4(+)CD25(high) regulatory T cells and to investigate their capacity for inhibiting the proliferation of CD4(+) CD25(-) effector T cells (Teffs). Peripheral blood samples were obtained from 15 patients with severe atopic dermatitis (AD) and 20 control subjects. FACs was then carried out to analyze the expression levels of FoxP3, CD152 (CTLA-4), CD39, CD73, CD223 (LAG-3), CCR4, CCR5, and CCR10 on Tregs. The proliferative responses of Teffs were assessed in the absence or presence of autologous Tregs and the TGF-ß1 and IL-10 levels in the culture supernatant and sera were detected by enzyme-linked immunosorbent assay (ELISA). The CD152, CD39, CD73, CCR4, and CCR5 expression levels on Tregs were higher in patients with severe AD than in the controls. Tregs showed an attenuated suppressive function of the proliferation of autologous Teffs in severe AD. The concentrations of IL-10 and TGF-ß in the culture supernatants of Tregs were lower in the AD group than in the control. The attenuated ability of Tregs to suppress Teff proliferation may be responsible for the autoimmune reaction of severe AD.

Plasma IL-6 levels are independently associated with atherosclerosis and mortality in HIV-infected individuals on suppressive antiretroviral therapy.

OBJECTIVE: To determine the associations of markers of immune activation with atherosclerosis and mortality, in participants with treated and suppressed HIV infection. DESIGN: Observational study of 149 HIV-infected participants with virologic suppression on antiretroviral therapy. METHODS: Cryopreserved mononuclear cells and plasma were used to evaluate markers of T cell and monocyte activation, inflammation and coagulopathy. Carotid artery intima-media thickness (CIMT) was measured by high-resolution ultrasound at the common, bifurcation and internal carotid regions. Associations of immunologic markers with CIMT and all-cause mortality were assessed using multivariable linear regression and Cox proportional hazards regression. RESULTS: The majority of participants were men (93%) and white (67%), median age of 48.5 years and median CD4 T-cell count of 522 cells/µl. The median baseline IMT was 1.0 mm. Over a median of 8.3-year follow-up, 12 deaths occurred. In multivariate analysis, adjusted for traditional cardiovascular risk factors, higher monocyte C-C motif chemokine receptor 5 (CCR5) expression [5.4%, P = 0.001] was associated with greater common CIMT. Higher plasma IL-6 was associated with greater bifurcation [8.0%, P = 0.007] and overall mean IMT [5.2%, P = 0.026]. Finally, higher plasma IL-6 [hazard ratio 1.9, P = 0.030], internal carotid [hazard ratio 4.1, P = 0.022] and mean IMT [hazard ratio 5.2, P = 0.026] were individually associated with all-cause mortality. CONCLUSION: Higher monocyte CCR5 expression and plasma IL-6 were associated with atherosclerosis, independent of traditional cardiovascular risk factors. IL-6 and CIMT were individually associated with all-cause mortality. The impact of therapies targeting immune activation in cardiovascular disease in treated HIV infection merits additional investigation.

64Cu-Doped PdCu@Au Tripods: A Multifunctional Nanomaterial for Positron Emission Tomography and Image-Guided Photothermal Cancer Treatment.

This article reports a facile synthesis of radiolabeled PdCu@Au core-shell tripods for use in positron emission tomography (PET) and image-guided photothermal cancer treatment by directly incorporating radioactive (64)Cu atoms into the crystal lattice. The tripod had a unique morphology determined by the PdCu tripod that served as a template for the coating of Au shell, in addition to well-controlled specific activity and physical dimensions. The Au shell provided the nanostructure with strong absorption in the near-infrared region and effectively prevented the Cu and (64)Cu atoms in the core from oxidization and dissolution. When conjugated with D-Ala1-peptide T-amide (DAPTA), the core-shell tripods showed great enhancement in targeting the C-C chemokine receptor 5 (CCR5), a newly identified theranostic target up-regulated in triple negative breast cancer (TNBC). Specifically, the CCR5-targeted tripods with an arm length of about 45 nm showed 2- and 6-fold increase in tumor-to-blood and tumor-to-muscle uptake ratios, respectively, relative to their nontargeted counterpart in an orthotopic mouse 4T1 TNBC model at 24 h postinjection. The targeting specificity was further validated via a competitive receptor blocking study. We also demonstrated the use of these targeted, radioactive tripods for effective photothermal treatment in the 4T1 tumor model as guided by PET imaging. The efficacy of treatment was confirmed by the significant reduction in tumor metabolic activity revealed through the use of (18)F-fluorodeoxyglucose PET/CT imaging. Taken together, we believe that the (64)Cu-doped PdCu@Au tripods could serve as a multifunctional platform for both PET imaging and image-guided photothermal cancer therapy.

High-dose cyclophosphamide induces specific tumor immunity with concomitant recruitment of LAMP1/CD107a-expressing CD4-positive T cells into tumor sites.

Cancer chemotherapy regimens, particularly those employing high-dose cytotoxic drugs such as cyclophosphamide (CTX), have been considered to be immune suppressive. However, we observed that a single administration of high-dose CTX abolished tumors arising from subcutaneous injection of a mouse hepatoma cell line and subsequently induced specific tumor immunity. Depletion of T cells, specifically CD4(+) T cells, abrogated the CTX-mediated tumor regression. CTX treatment induced the rapid recruitment of CD4(+) T cells into the tumors, and these recruited cells initiated expression of LAMP1/CD107a, a cytotoxic granule molecule, and granzyme B in the absence of antigen presentation at draining lymph nodes and proliferation in the tumor tissues. Moreover, CTX enhanced the expression of a CC chemokine, CCL3, in tumor tissues, and CTX-mediated tumor regression was attenuated in mice deficient in CCR5, the receptor for this chemokine. Consistently, less CTX-induced accumulation of intratumoral LAMP1/CD107a-expressing CD4(+) T cells was observed in mice receiving splenocytes derived from CCR5-deficient mice than in those receiving splenocytes derived from WT mice. Thus, CTX induces the expression of CCL3, which induces the intratumoral migration of CD4(+) T cells expressing cytotoxic molecules, leading to tumor eradication and subsequent specific tumor immunity.

Heroin use in Indonesia is associated with higher expression of CCR5 on CD4+ cells and lower ex-vivo production of CCR5 ligands.

Opioid use may affect HIV infection through altered expression of HIV co-receptors. This was examined in Indonesia among antiretroviral therapy-naive HIV patients, many of whom use drugs. C-C chemokine receptor type 5 (CCR5) expression on CD4+ cells was higher in heroin (P = 0.007), methadone (P = 0.024) and former opioid users (P = 0.003) compared to nonusers, whereas production of RANTES and other CCR5 ligands was similar or lower. This suggests that opioids can affect HIV susceptibility through up-regulation of CCR5 or down-regulation of its ligands.

The saponin DT-13 inhibits gastric cancer cell migration through down-regulation of CCR5-CCL5 axis.

AIM: To investigate the effect of DT-13 on gastric cancer cell migration, and to explore the possible mechanisms underlying the anti-metastasis activity of DT-13. METHODS: Growth inhibition of DT-13 was analyzed by the MTT assay. Cell migration was measured by the scratch-wound assay and transwell double chamber assay. To investigate the possible mechanisms underlying the anti-metastasis activity of DT-13, chemokine receptors that are involved in cancer metastasis (CCR2, CCR5, CCR7, CXCR4, and CXCR6) were detected by conventional PCR. The effect of DT-13 on CCR5 and CXCR4 expression was further evaluated by quantitative PCR and Western blot, respectively. The secretion of CCL5 (ligand of CCR5) and SDF-1 (ligand of CXCR4) were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: DT-13 inhibited BGC-823 and HGC-27 cell growth in a dose dependent manner, and the estimated IC50 value for 24 h treatment was 23.5 ± 5.1 µmol·L(-1) for BGC-823 cells and 35.6 ± 7.6 µmol·L(-1) for HGC-27 cells. DT-13 also significantly decreased gastric cancer cell migration. DT-13 significantly decreased the gene expression of CCR5 in both BGC-823 and HGC-27 gastric cancer cells, and moderately reduced the expression of CXCR4. Similar to the results of gene expression, significant down-regulation of CCR5 protein was observed, but CXCR4 protein levels were much less affected. CCL5 secretion, but not SDF-1 production, was inhibited by DT-13. CONCLUSION: DT-13 inhibited gastric cancer cell migration by down-regulation of the CCR5-CCL5 axis.

HIV replication in conjunction with granzyme B production by CCR5+ memory CD4 T cells: Implications for bystander cell and tissue pathologies.

Granzyme B (GrzB) is expressed by activated T cells and mediates cellular apoptosis. GrzB also acts as an extracellular protease involved in tissue degradation. We hypothesized that GrzB production from activated memory CD4 T cells may be associated with HIV pathogenesis. We found that stimulated memory CD4 T cells (via costimulation, cytokines, and TLR ligands) concomitantly produced GrzB and HIV. Both GrzB and HIV expression were mainly restricted to CCR5-expressing memory CD4+CD45RO+ T cells, including Th1 and Th17 subsets. Activated memory CD4 T cells also mediated tissue damage, such as disruption of intestinal epithelial monolayers. In non-human primates, CD4 T cells of rhesus macaques (pathogenic SIV hosts) expressed higher GrzB compared to African green monkeys (non-pathogenic SIV hosts). These results suggest that GrzB from CCR5+ memory CD4 T cells may have a role in cellular and tissue pathologies during HIV infection.

Helminth-associated systemic immune activation and HIV co-receptor expression: response to albendazole/praziquantel treatment.

BACKGROUND: It has been hypothesized that helminth infections increase HIV susceptibility by enhancing systemic immune activation and hence contribute to elevated HIV-1 transmission in sub-Saharan Africa. OBJECTIVE: To study systemic immune activation and HIV-1 co-receptor expression in relation to different helminth infections and in response to helminth treatment. METHODS: HIV-negative adults with (n = 189) or without (n = 57) different helminth infections, as diagnosed by Kato-Katz, were enrolled in Mbeya, Tanzania. Blinded to helminth infection status, T cell differentiation (CD45RO, CD27), activation (HLA-DR, CD38) and CCR5 expression was determined at baseline and 3 months after Albendazole/Praziquantel treatment. Plasma cytokine levels were compared using a cytometric bead array. RESULTS: Trichuris and Ascaris infections were linked to increased frequencies of "activated" CD4 and/or CD8 T cells (p<0.05), whereas Hookworm infection was associated with a trend towards decreased HLA-DR+ CD8 T cell frequencies (p = 0.222). In Trichuris infected subjects, there was a linear correlation between HLA-DR+ CD4 T cell frequencies and the cytokines IL-1ß and IL-10 (p<0.05). Helminth treatment with Albendazole and Praziquantel significantly decreased eosinophilia for S. mansoni and Hookworm infections (p<0.005) but not for Trichuris infection and only moderately modulated T cell activation. CCR5 surface density on memory CD4 T cells was increased by 1.2-fold during Trichuris infection (p-value: 0.053) and reduced after treatment (p = 0.003). CONCLUSIONS: Increased expression of T cell activation markers was associated with Trichuris and Ascaris infections with relatively little effect of helminth treatment.

Innate immune interleukin-1 receptor-associated kinase 4 exacerbates viral myocarditis by reducing CCR5(+) CD11b(+) monocyte migration and impairing interferon production.

BACKGROUND: Viral myocarditis follows a fatal course in ≈30% of patients. Interleukin-1 receptor-associated kinase 4 (IRAK4), a major nodal signal transducer in innate immunity, can play a pivotal role in host inflammatory response. We sought to determine how IRAK4 modulates inflammation and outcome in a mouse model of viral myocarditis. METHODS AND RESULTS: Myocarditis was induced after intraperitoneal inoculation of coxsackievirus B3 into C57Bl/6 IRAK4-deficient mice and their littermate controls. Mortality and viral proliferation were markedly reduced in IRAK4(-/-) mice compared with their IRAK4(+/+) littermates. Disease resistance of IRAK4(-/-) mice paralleled increased amounts of protective heart-infiltrating CCR5(+) monocytes/macrophages and enhanced interferon-α and interferon-γ production 2 days after infection. Competitive bone marrow chimera demonstrated that intact IRAK4 function inhibited heart-specific migration of bone marrow-derived CCR5(+) cells. Mechanistically, lack of IRAK4 resulted in interferon regulatory factor 5 homodimerization via reduced melanoma differentiation-associated protein 5 degradation and enhanced Stat1 and Stat5 phosphorylation. Consequently, antiviral interferon-α and interferon-γ production, as well as CCR5(+) cell recruitment, increased, whereas the overall proinflammatory response was drastically reduced in the absence of IRAK4. CONCLUSIONS: Innate immunity signal transducer IRAK4 exacerbates viral myocarditis through inhibition of interferon production and reduced mobilization of protective CCR5(+) monocytes/macrophages to the heart. The combination of IRAK4 inhibitors and antiviral adjuvants may become an attractive therapeutic approach against viral myocarditis in the future.

Attenuation of HIV-1 replication in macrophages by cannabinoid receptor 2 agonists.

Infiltrating monocytes and macrophages play a crucial role in the progression of HIV-1 infection in the CNS. Previous studies showed that activation of the CB2 can attenuate inflammatory responses and affect HIV-1 infectivity in T cells and microglia. Here, we report that CB2 agonists can also act as immunomodulators on HIV-1-infected macrophages. First, our findings indicated the presence of elevated levels of CB2 expression on monocytes/macrophages in perivascular cuffs of postmortem HIV-1 encephalitic cases. In vitro analysis by FACS of primary human monocytes revealed a step-wise increase in CB2 surface expression in monocytes, MDMs, and HIV-1-infected MDMs. We next tested the notion that up-regulation of CB2 may allow for the use of synthetic CB2 agonist to limit HIV-1 infection. Two commercially available CB2 agonists, JWH133 and GP1a, and a resorcinol-based CB2 agonist, O-1966, were evaluated. Results from measurements of HIV-1 RT activity in the culture media of 7 day-infected cells showed a significant decrease in RT activity when the CB2 agonist was present. Furthermore, CB2 activation also partially inhibited the expression of HIV-1 pol. CB2 agonists did not modulate surface expression of CXCR4 or CCR5 detected by FACS. We speculate that these findings indicate that prevention of viral entry is not a central mechanism for CB2-mediated suppression in viral replication. However, CB2 may affect the HIV-1 replication machinery. Results from a single-round infection with the pseudotyped virus revealed a marked decrease in HIV-1 LTR activation by the CB2 ligands. Together, these results indicate that CB2 may offer a means to limit HIV-1 infection in macrophages.

Comprehensive assessment of HIV target cells in the distal human gut suggests increasing HIV susceptibility toward the anus.

BACKGROUND: Prevention of rectal HIV transmission is a high-priority goal for vaccines and topical microbicides because a large fraction of HIV transmissions occurs rectally. Yet, little is known about the specific target-cell milieu in the human rectum other than inferences made from the colon. METHODS: We conducted a comprehensive comparative in situ fluorescence study of HIV target cells (CCR5-expressing T cells, macrophages, and putative dendritic cells) at 4 and 30 cm proximal of the anal canal in 29 healthy individuals, using computerized analysis of digitized combination stains. RESULTS: Most strikingly, we find that more than 3 times as many CD68 macrophages express the HIV coreceptor CCR5 in the rectum than in the colon (P = 0.0001), and as such rectal macrophages seem biologically closer to the HIV-susceptible CCR5 phenotype in the vagina than the mostly HIV-resistant CCR5 phenotype in the colon. Putative CD209 dendritic cells are generally enriched in the colon compared with the rectum (P = 0.0004), though their CCR5 expression levels are similar in both compartments. CD3 T-cell densities and CCR5 expression levels are comparable in the colon and rectum. CONCLUSIONS: Our study establishes the target-cell environment for HIV infection in the human distal gut and demonstrates in general terms that the colon and rectum are immunologically distinct anatomical compartments. Greater expression of CCR5 on rectal macrophages suggests that the most distal sections of the gut may be especially vulnerable to HIV infection. Our findings also emphasize that caution should be exercised when extrapolating data obtained from colon tissues to the rectum.