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Development of cytomegalovirus (CMV) immune recovery uveitis is associated with Th17 cell depletion and poor systemic CMV-specific T cell responses.
Backgroundthe immune reconstitution inflammatory syndromes (IRIS) are a spectrum of inflammatory conditions associated with opportunistic infections and occurring in approximately16% of human immunodeficiency type 1 (HIV-1)-infected patients given antiretroviral therapy. It has been proposed that these conditions are linked by a dysregulated immune system that is prone to exaggerated responses. However, immunologic studies have been limited by the availability of longitudinal samples from patients with IRIS and appropriate matched control subjects. Cytomegalovirus (CMV) immune recovery uveitis (IRU) is an IRIS occurring in up to 38% of patients with CMV retinitis. Although the pathologic immune responses occur in the eye, immune dysregulation that allows for development of pathologic responses is presumably caused by faulty systemic immune cell reconstitution.Methodswe examined CMV-specific T cell responses, regulatory T (T(reg)) cell function and polyclonal T cell responses, including IL-17 production, in 25 patients with CMV IRU and 49 immunorestored control subjects with CMV retinitis who did not develop IRU.Resultspatients with CMV IRU had poor CMV-specific CD4(+) T cell responses, as compared with control subjects, whereas CD8(+) T cell responses were comparable. Patients with CMV IRU were characterized by smaller numbers of circulating Th17 cells. Deficiency in anti-CMV responses was not associated with differences in T(reg) cell function.Conclusionsthe T(reg) cell compartment is intact in patients with CMV IRU, and these patients do not develop exaggerated systemic CMV-specific or polyclonal immune responses. Cases are instead characterized by more profound depletion of Th17 cells and poor antiviral immune responses. CMV IRU may be most likely to develop in persons experiencing the greatest degree of immune dysfunction before initiating highly active antiretroviral therapy
The Bone Marrow Edema Links to an Osteoclastic Environment and Precedes Synovitis During the Development of Collagen Induced Arthritis
Objectives: To determine the relationship between bone marrow edema (BME), synovitis, and bone erosion longitudinally using a collagen induced arthritis mice (CIA) model and to explore the potential pathogenic role of BME in bone erosion.Methods: CIA was induced in DBA/1J mice. BME and corresponding clinical symptoms of arthritis and synovitis during the different time points of CIA development were assayed by magnetic resonance imaging (MRI), arthritis sore, and histologic analyses. The expression of osteoclasts (OCs), OCs-related cytokines, and immune cells in bone marrow were determined by flow cytometry, immunohistochemistry, immunofluorescence staining, and real-time PCR. The OCs formation was estimated using in vitro assays.Results: MRI detected BME could emerge at day 25 in 70% mice after the first immunization (n = 10), when there were not any arthritic symptoms, histological or MRI synovitis. At day 28, BME occurred in 90% mice whereas the arthritic symptom and histological synovitis were only presented in 30 and 20% CIA mice at that time (n = 10). The emergence of BME was associated with an increased bone marrow OCs number and an altered distribution of OCs adherent to subchondral bone surface, which resulted in increased subchondral erosion and decreased trabecular bone number during the CIA process. Obvious marrow environment changes were identified after BME emergence, consisting of multiple OCs related signals, including highly expressed RANKL, increased proinflammatory cytokines and chemokines, and highly activated T cells and monocytes.Conclusions: BME reflects a unique marrow “osteoclastic environment,” preceding the arthritic symptoms and synovitis during the development of CIA
Development of Cytomegalovirus (CMV) Immune Recovery Uveitis Is Associated with Th17 Cell Depletion and Poor Systemic CMV-Specific T Cell Responses
We tested whether impaired systemic immunoregulation and hyperactive immune responses are associated with an immune reconstitution inflammatory syndrome, CMV IRU. We found instead that T-regs in CMV IRU patients are functionally intact, while virus-specific immune responses and Th17 cells are compromise
ObjSim: Lightweight Automatic Patch Prioritization via Object Similarity
In the context of test case based automatic program repair (APR), patches
that pass all the test cases but fail to fix the bug are called overfitted
patches. Currently, patches generated by APR tools get inspected manually by
the users to find and adopt genuine fixes. Being a laborious activity hindering
widespread adoption of APR, automatic identification of overfitted patches has
lately been the topic of active research. This paper presents engineering
details of ObjSim: a fully automatic, lightweight similarity-based patch
prioritization tool for JVM-based languages. The tool works by comparing the
system state at the exit point(s) of patched method before and after patching
and prioritizing patches that result in state that is more similar to that of
original, unpatched version on passing tests while less similar on failing
ones. Our experiments with patches generated by the recent APR tool PraPR for
fixable bugs from Defects4J v1.4.0 show that ObjSim prioritizes 16.67% more
genuine fixes in top-1 place. A demo video of the tool is located at
https://bit.ly/2K8gnYV.Comment: Proceedings of the 29th ACM SIGSOFT International Symposium on
Software Testing and Analysis (ISSTA '20), July 18--22, 2020, Virtual Event,
US
Stroke Dysbiosis Index (SDI) in Gut Microbiome Are Associated With Brain Injury and Prognosis of Stroke
Background: Significant dysbiosis occurs in the gut microbiome of stroke patients. Condensing these broad, complex changes into one index would greatly facilitate the clinical usage of gut microbiome data. Here, we formulated a gut microbiota index in patients with acute ischemic stroke based on their gut microbiota dysbiosis patterns and tested whether the index was correlated with brain injury and early outcome.Methods: A total of 104 patients with acute ischemic stroke and 90 healthy individuals were recruited, and their gut microbiotas were compared and to model a Stroke Dysbiosis Index (SDI), which representing stroke-associated dysbiosis patterns overall. Another 83 patients and 70 controls were recruited for validation. The association of SDI with stroke severity (National Institutes of Health Stroke Scale [NIHSS] score) and outcome (modified Rankin scale [mRS] score: favorable, 0–2; unfavorable, >2) at discharge was also assessed. A middle cerebral artery occlusion (MCAO) model was used in human flora-associated (HFA) animals to explore the causal relationship between gut dysbiosis and stroke outcome.Results: Eighteen genera were significantly different between stroke patients and healthy individuals. The SDI formula was devised based on these microbiome differences; SDI was significantly higher in stroke patients than in healthy controls. SDI alone discriminated stroke patients from controls with AUCs of 74.9% in the training cohort and 84.3% in the validation cohort. SDI was significantly and positively correlated with NIHSS score on admission and mRS score at discharge. Logistic regression analysis showed that SDI was an independent predictor of severe stroke (NIHSS ≥8) and early unfavorable outcome (mRS >2). Mice receiving fecal transplants from high-SDI patients developed severe brain injury with elevated IL-17+ γδ T cells in gut compared to mice receiving transplants from low-SDI patients (all P < 0.05).Conclusions: We developed an index to measure gut microbiota dysbiosis in stroke patients; this index was significantly correlated with patients' outcome and was causally related to outcome in a mouse model of stroke. Our model facilitates the potential clinical application of gut microbiota data in stroke and adds quantitative evidence linking the gut microbiota to stroke
High CD8+ T Cell Activation Marks a Less Differentiated HIV-1 Specific CD8+ T Cell Response that Is Not Altered by Suppression of Viral Replication
The relationship of elevated T cell activation to altered T cell differentiation profiles, each defining features of HIV-1 infection, has not been extensively explored. We hypothesized that anti-retroviral suppression of T cell activation levels would lead to alterations in the T cell differentiation of total and HIV-1 specific CD8+ T cell responses among recently HIV-1 infected adults.We performed a longitudinal study simultaneously measuring T cell activation and maturation markers on both total and antigen-specific T cells in recently infected adults: prior to treatment; after the initiation of HAART; and after treatment was halted. Prior to treatment, HIV-1 Gag-specific CD8+ T cells were predominantly of a highly activated, intermediate memory (CD27+CD28-) phenotype, while CMV pp65-specific CD8+ T cells showed a late memory (CD27-CD28-), low activation phenotype. Participants with the highest fraction of late memory (CD27-CD28-) HIV-1-specific CD8+ T cells had higher CD4+ T cell counts (rho = +0.74, p = 0.004). In turn, those with the highest fraction of intermediate memory (CD27+ CD28-) HIV-1 specific CD8+ T cells had high total CD8+ T cell activation (rho = +0.68, p = 0.01), indicating poorer long-term clinical outcomes. The HIV-1 specific T cell differentiation profile was not readily altered by suppression of T cell activation following HAART treatment.A more differentiated, less activated HIV-1 specific CD8+ T cell response may be clinically protective. Anti-retroviral treatment initiated two to four months after infection lowered T cell activation but had no effect on the differentiation profile of the HIV-1-specific response. Intervention during the first month of acute infection may be required to shift the differentiation phenotype of HIV-1 specific responses to a more clinically favorable profile
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