Blood biomarkers associated with inflammation predict poor prognosis in cerebral venous thrombosis:: a multicenter prospective observational study

BACKGROUND AND PURPOSE

Experimental studies suggest inflammation can contribute to blood barrier disruption and brain injury in cerebral venous thrombosis (CVT). We aimed to determine whether blood biomarkers of inflammation were associated with the evolution of brain lesions, persistent venous occlusion or functional outcome in patients with CVT.

METHODS

Pathophysiology of Venous Infarction-Prediction of Infarction and Recanalization in CVT (PRIORITy-CVT) was a multicenter prospective cohort study of patients with newly diagnosed CVT. Evaluation of neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) concentrations in peripheral blood samples was performed at admission in 62 patients. Additional quantification of interleukin (IL)-6 was performed at day 1, 3 and 8 in 35 patients and 22 healthy controls. Standardized magnetic resonance imaging was performed at day 1, 8 and 90. Primary outcomes were early evolution of brain lesion, early recanalization and functional outcome at 90 days.

RESULTS

Interleukin-6 levels were increased in patients with CVT with a peak at baseline. IL-6, NLR and CRP levels were not related with brain lesion outcomes or early recanalization but had a significant association with unfavourable functional outcome at 90 days (IL-6: OR = 1.28, 95% CI: 1.05-1.56, P = 0.046; NLR: OR = 1.39, 95% CI: 1.4-1.87, P = 0.014; CRP: OR = 1.756, 95% CI: 1.010-3.051, P = 0.029). Baseline IL-6 had the best discriminative capacity, with an area under the receiver operating characteristic curve to predict unfavourable functional outcome of 0.74 (P = 0.031).

CONCLUSIONS

Increased baseline levels of NLR, CRP and IL-6 may serve as new predictive markers of worse functional prognosis at 90 days in patients with CVT. No association was found between inflammatory markers and early evolution of brain lesion or venous recanalization.

HIV-2 infection is associated with preserved GALT homeostasis and epithelial integrity despite ongoing mucosal viral replication

The mechanisms that enable preservation of gut mucosal integrity during persistent viral replication and inherent inflammation remain unclear. Here, we investigated, for the first time, gut homeostasis in HIV-2 infection, a naturally occurring form of attenuated HIV disease. We found viral replication in both sigmoid and ileum of asymptomatic HIV-2+ patients (range: 240-851 circulating CD4+T-cells per μl) despite their undetectable viremia, accompanied by interferon-γ-producing CD8 T-cell expansion, irrespective of antiretroviral treatment. Nevertheless, there was no CD4 T-cell depletion, and Foxp3+ and IL-17- or IL-22-producing CD4 T-cell numbers were unaffected. Moreover, IL-22-producing innate lymphoid cells and IL-22-induced antimicrobial peptides and mucins were maintained. In agreement, the epithelium histology was preserved, including tight junction protein zonula occludens (ZO-1) levels. Furthermore, in vitro infection of colon epithelia with primary isolates revealed no HIV-2 impact on ZO-1 expression. Notably, sigmoid transcriptional levels of CCL20 and CCL28 were significantly increased, in direct correlation with GM-CSF, indicating a local response able to enhance CD4 T-cell recruitment. In conclusion, maintenance of mucosal integrity in HIV-2 infection was associated with T-cell recruitment responses, potentially counteracting CD4 T-cell depletion due to HIV-2 replication. These data have unique implications for the design of therapies targeting gut homeostasis in HIV-1 infection and other chronic inflammatory settings.

Bee venom enhances the differentiation of human regulatory T cells

Venom-specific immunotherapy (VIT) is well recognized by its efficacy, and compelling evidence implicates regulatory T cells (Tregs) in the underlying tolerogenic mechanisms. Additionally, hymenoptera venom has for a long time been claimed to modulate immunity. Here, we investigated the putative role of bee venom (Bv) in human FOXP3-expressing Treg homeostasis and differentiation, irrespective of the donors' allergic status. We found that Bv significantly enhanced the differentiation of FOXP3-expressing cells both from conventional naïve CD4 T cells and mature CD4 thymocytes, a property that may contribute to the VIT's capacity to expand circulating Tregs in allergic individuals. We expect that our data enlightening the Treg-mediated immunomodulatory properties of Bv regardless of TCR specificity, to have application in other allergies, as well as in other clinical settings, such as autoimmunity and transplantation.

Monocyte activation is a feature of common variable immunodeficiency irrespective of plasma lipopolysaccharide levels

Common variable immunodeficiency disorders (CVID), the most frequent cause of symptomatic primary immunodeficiency, are defined by impaired antibody production. Notwithstanding, T cell activation and granulomatous manifestations represent the main causes of CVID morbidity even in patients receiving immunoglobulin (Ig) G replacement therapy. Additionally, gut pathology is a frequent feature of CVID. In this study, we investigated monocyte imbalances and their possible relationship with increased microbial translocation in CVID patients. Monocyte subsets were defined according to CD14 and CD16 expression levels and evaluated in terms of human leucocyte antigen D-related (HLA-DR), CD86 and programmed death-1 molecule ligand 1 (PD-L1) expression by flow cytometry, in parallel with the quantification of plasma lipopolysaccharide (LPS) and serum levels of soluble CD14 (sCD14), LPS-binding protein (LBP) and anti-LPS antibodies. CVID patients (n=31) featured significantly increased levels of serum sCD14 and an expansion of CD14(bright) CD16(+) monocytes in direct correlation with T cell and B cell activation, the latter illustrated by the frequency of the CD21(low) CD38(low) subset. Such alterations were not observed in patients lacking B cells due to congenital agammaglobulinaemia (n=4). Moreover, we found no significant increase in circulating LPS or LBP levels in CVID patients, together with a relative preservation of serum anti-LPS antibodies, in agreement with their presence in commercial IgG preparations. In conclusion, CVID was associated with monocyte imbalances that correlated directly with T cell activation markers and with B cell imbalances, without an association with plasma LPS levels. The heightened monocyte activated state observed in CVID may represent an important target for complementary therapeutic strategies.

Expansion of circulating Foxp3+)D25bright CD4+ T cells during specific venom immunotherapy

BACKGROUND

Venom immunotherapy (VIT) induces long-lasting immune tolerance to hymenoptera venom antigens, but the underlying mechanisms are not yet clarified. Regulatory T cells are thought to play an important role in allergic diseases and tolerance induction during specific immunotherapy.

AIM

Characterize longitudinally the impact of VIT on the pool of circulating regulatory T cells.

METHODS

Fourteen hymenoptera venom-allergic patients with severe reactions (grades III-IV) were studied before, 6 and 12 months after starting ultra-rush VIT. Freshly isolated peripheral blood mononuclear cells were surface stained with a panel of markers of T cell differentiation and intracellularly for CTLA-4 and Foxp3 and analysed by flow cytometry. foxp3 mRNA was quantified by real-time PCR. VIT responses were assessed by measuring specific IgG4 and IgE levels. Eleven individuals with no history of insect venom allergy were studied as controls.

RESULTS

VIT induces a significant progressive increase in both the proportion and the absolute numbers of regulatory T cells defined as CD25bright and/or Foxp3+ CD4+ T cells. These changes are not related to alterations in the expression of activation markers or imbalances in the naïve/memory T cell compartments. foxp3 mRNA levels also increased significantly during VIT. Of note, the increase in circulating regulatory T cell counts significantly correlates with the venom-specific IgG4/IgE ratio shift.

CONCLUSION

VIT is associated with a progressive expansion of circulating regulatory T cells, supporting a role for these cells in tolerance induction.

Comparison of the frequency of interleukin (IL)-2-, interferon-gamma-, and IL-4-producing T cells in 2 diseases, human immunodeficiency virus types 1 and 2, with distinct clinical outcomes

Human immunodeficiency virus (HIV) type 2 infection is associated with a better clinical outcome, slower rates of CD4 T cell decline, and lower viremia than is HIV-1. This study compares HIV-1 and HIV-2 in regard to the percentages of interleukin (IL)-2-, interferon (IFN)-gamma-, and IL-4-producing cells at the single-cell level, as determined by flow cytometry. At a given degree of CD4 T cell depletion, the frequency of T cells able to produce IL-2 is better preserved in HIV-2 than in HIV-1 infection, particularly within the CD4 T cell subset. As described for HIV-1 immunodeficiency, HIV-2-positive patients exhibit a marked expansion of terminally differentiated effector CD8 T cells (CD28(-)CD27(-)IFN-gamma(+)). However, the proportion of CD8 T cells able to simultaneously produce IL-2 and IFN-gamma is higher in HIV-2 disease. Considering the central role of IL-2 as a lymphocyte proliferative and survival factor, these findings provide a possible immunologic basis for the distinct course of HIV-2 immunodeficiency.

Marked immunosuppressive effects of the HIV-2 envelope protein in spite of the lower HIV-2 pathogenicity

OBJECTIVE

HIV-1 envelope proteins have immunosuppressive properties and it is thought that they have a role in the establishment of immunodeficiency. This study characterizes the immunological effects of HIV-2 envelope protein gp105, a virus which is associated with a slower rate of disease progression.

METHODS

The effects of recombinant baculovirus-expressed envelope proteins from HIV-IIIB HIV-1MN, HIV-2ROD and SIVmac251 on anti-CD3-stimulated peripheral blood mononuclear cells (PBMC) from healthy donors were evaluated by incorporation of 3H-thymidine, flow cytometric analysis of bromodeoxyuridine incorporation in different T cell subsets, kinetics of expression of costimulatory molecules (CD40L/OX40) and assessment of cell death by annexin V/propidium iodide staining. The effects on production of tumour necrosis factor alpha (TNF-alpha) by monocytes were assessed at the single-cell level after a 6 h culture of unstimulated PBMC.

RESULTS

HIV-2 gp105 was more inhibitory than HIV-1 gp120 of T cell proliferation and the upregulation of CD40L and OX40; in the absence of signficant induction of apoptosis. This inhibition affected both CD4 and CD8 T cells and was only partially reversed by costimulation with interleukin 2 or CD28. gp105 strongly inducted TNF-alpha production by monocytes.

CONCLUSION

The immunosuppressive properties of the HIV envelope proteins could be beneficial rather than detrimental to the host by interfering with the heightened state of immunocellular activation that characterizes HIV infection and by limiting the bursts of viral replication. This hypothesis could in part explain the slower decline of CD4 cell numbers in HIV-2 infection and deserves further exploration.

Bulk cytokine production versus frequency of cytokine-producing cells in HIV1 infection before and during HAART

Cytokine imbalances play a major role in HIV immunopathogenesis. This study analyzes simultaneously the frequency of cytokine-producing cells at the single cell level by flow cytometry and the disturbances in cytokine secretion assessed by ELISA in a cohort of asymptomatic HIV1 patients in different stages of CD4 depletion and during antiretroviral therapy (HAART). Early in the disease, there is an increased frequency of IFN-gamma(+) lymphocytes and bulk IFN-gamma production, in parallel with a reduced proportion of IL4(+) cells and IL4 secreted. The two IL4 measurements are significantly correlated. No such correlation was found for IFN-gamma, which is consistent with a large variation in the amount of IFN-gamma released per individual cell. Moreover, HAART was associated with a reduction to normal levels in the bulk IFN-gamma secretion concomitant with a persistency of the overexpanded IFN-gamma(+) cell subset in the peripheral blood. This study emphasizes the importance of using a conjoint approach to assess the cytokine network in trials of antiretroviral and/or immune-based therapies to avoid missing significant effects which are possibly relevant in the clinical setting.

[Headaches, otalgia and peripheral facial palsy as a form of presentation of neurosyphilis]

INTRODUCTION

Decrease in incidence of neurosyphilis over the last few decades implies that clinicians consider less frequently this diagnosis. On the other hand, some reports suggest an increase in atypical forms of this disease that represent an additional reason for missing this diagnosis.

CLINICAL CASE

We report on a 16 year-old immunocompetent black female from Guinea-Bissau presented with headaches, ear pain, hearing loss and peripheral facial paralysis. A cranial CT scan showed a hypodense area in the left cortico-subcortical zone and a contrast enhancement on the left pontocerebellar angle and internal auditory meatus. On the third day of admission a diagnosis of meningitis was made, with high titles of VDRL and TPHA in CSF and serum, leading to a diagnosis of neurosyphilis. The epidemiological aspects of this case suggest either a late congenital syphilis or an infection as a result of a blood transfusion administered seven years earlier in Guinea-Bissau.

CONCLUSION

This rare form of presentation of neurosyphilis emphasizes the importance of considering systematically this diagnosis, even in the context of atypical presentations.

Early reduction of the over-expression of CD40L, OX40 and Fas on T cells in HIV-1 infection during triple anti-retroviral therapy: possible implications for lymphocyte traffic and functional recovery

Fas, CD40L and OX40 are members of the tumour necrosis factor (TNF) receptor superfamily with critical roles in T cell activation and death, B cell function, dendritic cell maturation and leucocyte traffic regulation. The aim of this study was to evaluate the effects of anti-retroviral therapy (HAART) on CD40L, OX40 and Fas expression on freshly isolated peripheral blood T cells by three-colour flow cytometry and compare them with lymphoproliferative responses, peripheral blood cell counts and viral load. Fourteen asymptomatic HIV-1+ patients treated with Lamivudine, Stavudine and Nelfinavir were prospectively investigated sequentially for 48 weeks. At baseline, patients exhibited significantly enhanced proportions and counts of CD40L+ and OX40+ cells within the CD4 subset which were corrected by weeks 8-16 of HAART. Interestingly, in the five patients showing viral load rebound during therapy in spite of increasing CD4 counts, the reduction of the levels of these costimulatory molecules was similarly maintained. Therapy induced a decrease in the over-expression of Fas, particularly in the CD4 subset where normal levels were reached at week 8. This reduction occurred in parallel with the major recovery of lymphoproliferative responses. Higher basal levels and lower reduction of Fas were associated with suboptimal suppression of viraemia. In conclusion, this previously undescribed increased expression of CD40L and OX40 may play a role in the HIV-associated pan-immune activation and represent a possible target for immunointervention, as suggested for several immunologically mediated diseases. Moreover, HAART induced an early correction of the over-expression of Fas, CD40L and OX40 in CD4 T cells which could be involved in the recovery of the cell traffic disturbances and in the T cell renewal capacity.

Kinetics of the changes of lymphocyte subsets defined by cytokine production at single cell level during highly active antiretroviral therapy for HIV-1 infection

The effects of highly active antiretroviral therapy on cytokine imbalances associated with HIV-1 infection have not been characterized. Using single cell analysis by flow cytometry, we show that a significant recovery in the frequency of IL-2-producing cells was only observed in patients with a sustained control of viral replication and that the overexpanded CD8 T cell population of CD28- IFN-gamma + cells was not significantly reduced after 1 yr of effective therapy. Moreover, a detrimental role of IL-4 is suggested by the association between an enhanced proportion of IL-4-producing cells within the CD4 and particularly the CD8 subset and viral load rebound. Finally, the kinetics of changes of cell subsets assessed for simultaneous production of different cytokines supports the view that cell reconstitution during highly active antiretroviral therapy is initially due to redistribution of terminally differentiated cells, followed by peripheral expansion of less differentiated ones and a late progressive increase of the proportion of functionally defined naive/memory precursor lymphocytes. These data bring new support for the role of cytokine imbalances in AIDS pathogenesis and may be relevant for the definition of immunointervention targets.

Single-cell analysis of lymphokine imbalance in asymptomatic HIV-1 infection: evidence for a major alteration within the CD8+ T cell subset

In this study we investigated at single-cell level by flow cytometry the potential of T cell cytokine production in asymptomatic HIV-1-infected subjects with > 200 CD4 counts and possible correlation with T helper cell depletion and viral load. Mitogen-stimulated peripheral blood mononuclear cells from 32 HIV-1+ patients and 16 healthy subjects were intracytoplasmically stained for IL-2, interferon-gamma (IFN-gamma), IL-4 or IL-10, and the frequency of cytokine-producing cells was assessed in total T cells, CD4, CD8 and CD45RO subsets as well as in CD69+CD3+ gated lymphocytes. HIV-1+ patients, irrespective of their degree of CD4 depletion, exhibited a major increase in IFN-gamma+ CD8 T cells, largely due to CD28- cells, as well as a decrease in the capacity of CD8 T cells to produce IL-2. Patients with > 500 CD4 counts showed a diminished frequency of IL-4 expression in CD4 T cells and a negative correlation was found between this parameter and the ex vivo CD4 counts in the 32 patients. Analysis of patients stratified according to viral load revealed a significantly higher proportion of IL-2-producing CD4 cells in the group with < 5000 RNA copies/ml. In short, using single-cell analysis and an antigen-presenting cell-independent stimulus, we have not been able to find any significant cytokine imbalances in the CD4 subset, suggesting that the well described T helper defects are not due to intrinsic alterations in the potential of CD4 T cells to produce cytokines. On the other hand, the major disturbances in the CD8 T lymphocytes agree with the marked activation and possible replicative senescence of CD8 T cells and emphasize the role of this subset in HIV immunopathogenesis.

Centrocytic lymphoma presenting as a subphrenic abscess and a solitary liver nodule

Non Hodgkin's lymphoma revealed by hepatic manifestations is extremely rare. We describe here a 82-year old male patient who presented with a right subphrenic abscess and a solitary liver tumour that was shown to be a centrocytic lymphoma. Furthermore, asymptomatic cryptogenic liver cirrhosis was diagnosed. This previously unreported form of clinical presentation of a non Hodgkin's lymphoma as well as the association with liver cirrhosis are discussed in the context of the recent literature.

[The use of serological tests for detecting HIV infection in general clinical consultations and hospital consultations]

AIMS

To determine the number and type of HIV tests requested in general practice (GP) and in hospital outpatient clinics, to identify principle risk behaviors, to determine the percentage of HIV positive tests and to identify possible factors associated with the request of HIV tests.

METHODS

Cross-sectional, analytical and observational study, involving 80 GPs and 45 hospital specialists in the region of Lisbon. All requests for HIV tests were analysed during a 12 month period.

RESULTS

936 HIV tests were requested, with a mean of 12.47 in GP and 0.69 in the hospital. Risk behaviors observed were mainly heterosexual contacts and intravenous drug abuse (IVDA). The motives of the requests mainly were pregnancy, risk behaviors in GP and the presence of symptoms suggesting HIV infection in the hospital. The initiative of the request came from doctors in 70% of the cases. The percentage of HIV positive tests (ELISA + Western blot) was 4.2% in GP and 32% in the hospital. According to risk behaviors, the percentage of seropositivity was 33% in homo/bisexuals, 13% in IVDA, 7% in heterosexuals with risk behaviors and 0.2% in individuals with unidentified risk behaviors.

CONCLUSIONS

The patterns of request of HIV tests differ in hospital and in GP. In a significant percentage of cases, no informed consent was obtained prior to HIV testing, both in hospital and GP. This study may serve as an indicator of the need for information and education programs concerning HIV testing directed to health professionals and the general population.

[Cytomegalovirus-induced colitis in HIV infection. Considerations on its diagnosis, treatment and complications]

The diagnosis of cytomegalovirus intestinal disease in patients with HIV (human immunodeficiency virus) infection frequently raises diagnostic problems in view of the absence of definite pathological, serological or virological markers of active CMV infection. We describe the case of a 47-year-old man with a CMV colitis which illustrates several diagnostic and therapeutic problems and that was complicated by an intestinal perforation. We emphasize that in HIV+ patients with chronic diarrhea, the presence of abdominal pain should suggest the possibility of a CMV colitis and that in such cases a colonoscopy with biopsies of the right colon should be performed, in view of the higher frequency of the typical histopathological changes at this level. On the other hand, this case presented a marked thickening of the colon wall, simulating pseudotumoral images on CAT scans, as recently described in literature. The therapeutic possibilities as well as the complications of CMV colitis are discussed in the context of the occurrence of an ileal perforation, which represents the first report of this complication in Portuguese literature and which had the particularity of having a long survival after surgery in comparison with the previous cases described in international literature.

Takayasu's disease presenting as a nephrotic syndrome due to amyloidosis

We report an 18 year old black woman who presented with nephrotic syndrome in whom the investigations led to the diagnosis of diffuse Takayasu's disease, renal amyloidosis of AA type and interstitial lung disease. Proteinuria in Takayasu's disease is usually ascribed to hypertension or more rarely to glomerulonephritis. This case suggests that amyloidosis should be considered also in the investigation of proteinuria in these patients in view of the serious prognostic implications. This case represents further evidence that Takayasu's disease can be the cause of systemic reactive amyloidosis which may also be the presenting feature.