CD4 T-cell Apoptosis Research Articles

Macrophages Promote Atherosclerosis Development by Inhibiting CD8T Cell Apoptosis.

Atherosclerosis is an inflammatory cardiovascular disease. However, whether the association of immune cells in plaques promotes the progression of this disease has not yet been completely elucidated. Thus, this study aimed to investigate the relationship between C1q+ macrophages and CD8T cells through scRNA-seq data reanalysis, quantitative real-time PCR, and flow cytometry. Chromatin immunoprecipitation-quantitative polymerase chain reaction, western blot, and antibody-blocking experiments were performed to investigate the role of macrophage-CD8T interaction in atherosclerosis. An atherosclerotic mouse model was developed to confirm our findings. Mechanistically, Spi1 expression induced by granulocyte-macrophage colony-stimulating factor promoted C1q expression in the macrophages. Moreover, C1q+ macrophages suppressed CD8T cell apoptosis by upregulating Slc7a7 expression to enhance the L-arginine uptake of CD8T cells. CD8T-derived interferon-γ promoted macrophage activation to induce atherosclerosis. Blockade of the C1q-C1qbp axis attenuated atherosclerosis. In conclusion, macrophages interacting with CD8T promote atherosclerosis development via the C1q-C1qbp axis.

Mechanism Exploration on the Immunoregulation of Allogeneic Heart Transplantation Rejection in Rats With Exosome miRNA and Proteins From Overexpressed IDO1 BMSCs.

Immunoregulation and indoleamine 2,3-dioxygenase 1 (IDO1) play pivotal roles in the rejection of allogeneic organ transplantation. This study aims to elucidate the immune-related functional mechanisms of exosomes (Exos) derived from bone marrow-derived mesenchymal stem cells (BMSCs) overexpressing IDO1 in the context of allogeneic heart transplantation (HTx) rejection. A rat model of allogeneic HTx was established. Exos were extracted after transfection with oe-IDO1 and oe-NC from rat BMSCs. Exos were administered via the caudal vein for treatment. The survival of rats was analyzed, and reverse transcription qualitative PCR (RT-qPCR) and immunohistochemistry (IHC) were employed to detect the expression of related genes. Histopathological examination was conducted using hematoxylin and eosin (HE) staining, and flow cytometry was utilized to analyze T-cell apoptosis. Proteomics and RNA-seq analyses were performed on Exos. The data were subjected to functional enrichment analysis using the R language. A protein interaction network was constructed using the STRING database, and miRWalk, TargetScan, and miRDB databases predicted the target genes, differentially expressed miRNAs, and transcription factors (TFs). Exos from BMSCs overexpressing IDO1 prolonged the survival time of rats undergoing allogeneic HTx. These Exos reduced inflammatory cell infiltration, mitigated myocardial damage, induced CD4 T-cell apoptosis, and alleviated transplantation rejection. The correlation between Exos from BMSCs overexpressing IDO1 and immune regulation was profound. Notably, 13 immune-related differential proteins (Anxa1, Anxa2, C3, Ctsb, Hp, Il1rap, Ntn1, Ptx3, Thbs1, Hspa1b, Vegfc, Dcn, and Ptpn11) and 10 significantly different miRNAs were identified. Finally, six key immune proteins related to IDO1 were identified through common enrichment pathways, including Thbs1, Dcn, Ptpn11, Hspa1b, Il1rap, and Vegfc. Thirteen TFs of IDO1-related key miRNAs were obtained, and a TF-miRNA-mRNA-proteins regulatory network was constructed. Exosome miRNA derived from BMSCs overexpressing IDO1 may influence T-cell activation and regulate HTx rejection by interacting with mRNA.

Time-Dependent ROC Curve Analysis for Assessing the Capability of Radiation-Induced CD8 T-Lymphocyte Apoptosis to Predict Late Toxicities after Adjuvant Radiotherapy of Breast Cancer Patients.

Late fibrosis can occur in breast cancer patients treated with curative-intent radiotherapy. Predicting this toxicity is of clinical interest in order to adapt the irradiation dose delivered. Radiation-induced CD8 T-lymphocyte apoptosis (RILA) had been proven to be associated with less grade ≥2 late radiation-induced toxicities in patients with miscellaneous cancers. Tobacco smoking status and adjuvant hormonotherapy were also identified as potential factors related to late-breast-fibrosis-free survival. This article evaluates the predictive performance of the RILA using a ROC curve analysis that takes into account the dynamic nature of fibrosis occurrence. This time-dependent ROC curve approach is also applied to evaluate the ability of the RILA combined with the other previously identified factors. Our analysis includes a Monte Carlo cross-validation procedure and the calculation of an expected cost of misclassification, which provides more importance to patients who have no risk of late fibrosis in order to be able to treat them with the maximal irradiation dose. Performance evaluation was assessed at 12, 24, 36 and 50 months. At 36 months, our results were comparable to those obtained in a previous study, thus underlying the predictive power of the RILA. Based on specificity and cost, RILA alone seemed to be the most performant, while its association with the other factors had better negative predictive value results.

Association of polymorphisms in TGFB1, XRCC1, XRCC3 genes and CD8 T-lymphocyte apoptosis with adverse effect of radiotherapy for prostate cancer

The genetic background of each person might affect the severity of radiotherapy (RT)-induced normal tissue toxicity. The aim of study was to evaluate the influence of TGFB1 C-509T and Leu10Pro, XRCC1 Arg280His and XRCC3 Thr241Met polymorphisms as well as the level of radiation-induced CD8 T-lymphocyte apoptosis (RILA) on adverse effects of RT for prostate cancer (PCa). The study included 88 patients with localized or locally advanced PCa who were treated with RT. The polymorphisms were determined by PCR-RFLP analysis on DNA from peripheral blood mononuclear cells. RILA values were measured by flow cytometry. We found that CT genotype of TGFB1 C-509T could be protective biomarker for acute genitourinary (GU) and gastrointestinal (GI) radiotoxicity, while Thr variant of XRCC3 Thr241Met could predict the risk for acute GU radiotoxicity. Correlation between RILA values and toxicity was not detected. Univariate logistic regression analysis showed that Gleason score and risk group were risk factors for late GU, while for late GI radiotoxicity it was diabetes mellitus type 2. However, in multivariate model those were not proven to be significant and independent risk factors. Identification of assays combination predicting individual radiosensitivity is a crucial step towards personalized RT approach.

Low quantity and quality of anti-spike humoral response is linked to CD4 T-cell apoptosis in COVID-19 patients

In addition to an inflammatory reaction, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)-infected patients present lymphopenia, which we recently reported as being related to abnormal programmed cell death. As an efficient humoral response requires CD4 T-cell help, we hypothesized that the propensity of CD4 T cells to die may impact the quantity and quality of the humoral response in acutely infected individuals. In addition to specific immunoglobulins (Ig)A, IgM, and IgG against SARS-CoV-2 nucleocapsid (N), membrane (M), and spike (S1) proteins, we assessed the quality of IgG response by measuring the avidity index. Because the S protein represents the main target for neutralization and antibody-dependent cellular cytotoxicity responses, we also analyzed anti-S-specific IgG using S-transfected cells (S-Flow). Our results demonstrated that most COVID-19 patients have a predominant IgA anti-N humoral response during the early phase of infection. This specific humoral response preceded the anti-S1 in time and magnitude. The avidity index of anti-S1 IgG was low in acutely infected individuals compared to convalescent patients. We showed that the percentage of apoptotic CD4 T cells is inversely correlated with the levels of specific IgG antibodies. These lower levels were also correlated positively with plasma levels of CXCL10, a marker of disease severity, and soluble Fas ligand that contributes to T-cell death. Finally, we found lower S-Flow responses in patients with higher CD4 T-cell apoptosis. Altogether, these results demonstrate that individuals with high levels of CD4 T-cell apoptosis and CXCL10 have a poor ability to build an efficient anti-S response. Consequently, preventing CD4 T-cell death might be a strategy for improving humoral response during the acute phase, thereby reducing COVID-19 pathogenicity.

Association of Radiation-induced CD4 and CD8 T-Lymphocyte Apoptosis with Radiation-induced Fibrosis after Breast Conserving Therapy

Background: Around 70% of early breast cancer patients choose breast conserving therapy (BCT), with equal overall and disease-free survival rates compared to mastectomy. As a result, treatment decisions are currently guided by cosmetic outcomes and quality of life (QoL). Unfortunately, 13.4% of all BCT patients are affected by a grade 2 of radiation-induced fibrosis (RIF) of the breast. The individual risk of RIF could be predicted based the reduced radiation-induced lymphocyte apoptosis (RILA).

Raltegravir Inclusion Decreases CD4 T-Cells Intra-Cellular Viral Load and Increases CD4 and CD28 Positive T-Cells in Selected HIV Patients.

Raltegravir (RLT) prevents the integration of HIV DNA in the nucleus, but published studies remain controversial, suggesting that it does not decrease proviral DNA. However, there are only a few studies focused on virus-targeted cells. We aimed our study on the impact of RLT inclusion on total intra-cellular viral DNA (TID) in cellular subsets and immune effects in patients with newly acquired undetectable plasmatic viral load (UVL). Six patients having UVL using an antiretroviral combination for 6 months and CD4 T-cells > 350/mL and <500/mL were selected to receive RLT for 3 months from M0 to M3. Patients had 7 sequential viro-immunological determinations from M-1 to M5. Immune phenotypes were determined by flow cytometry and TID quantification was performed using PCR assay on purified cells. TID (median values) at the initiation of RLT in CD4 T-cells was 117 copies/millions of cells, decreased to 27.5 on M3, and remained thereafter permanently under the cut-off (<10 copies/millions of cells) in 4 out of 6 patients. This was associated with an increase of CD4 and CD4 + CD28+ T-cells and a decrease of HLA-DR expression and apoptosis of CD4 T-cells. RLT inclusion led to decreases in the viral load along with positive immune reconstitution, mainly for CD4 T-cells in HIV patients.

Telomere and ATM Dynamics in CD4 T-Cell Depletion in Active and Virus-Suppressed HIV Infections.

CD4 T-cell depletion is a hallmark of HIV/AIDS, but the underlying mechanism is still unclear. We have recently shown that ataxia-telangiectasia-mutated (ATM) deficiency in CD4 T cells accelerates DNA damage, telomere erosion, and cell apoptosis in HIV-infected individuals on antiretroviral therapy (ART). Whether these alterations in ART-treated HIV subjects occur in vitro in HIV-infected CD4 T cells remains unknown. In this study, we employed a cellular model of HIV infection to characterize the mechanisms underlying CD4 T-cell destruction by analyzing the telomeric DNA damage response (DDR) and cellular apoptosis in highly permissive SupT1 cells, followed by the validation of our observations in primary CD4 T cells with active or drug-suppressed HIV infection. Specifically, we established an in vitro HIV T-cell culture system with viral replication and raltegravir (RAL; an integrase inhibitor) suppression, mimicking active and ART-controlled HIV infection in vivo We demonstrated that HIV-induced, telomeric DDR plays a pivotal role in triggering telomere erosion, premature T-cell aging, and CD4 T-cell apoptosis or depletion via dysregulation of the PI3K/ATM pathways. This in vitro model provides a new tool to investigate HIV pathogenesis, and our results shed new light on the molecular mechanisms of telomeric DDR and CD4 T-cell homeostasis during HIV infection.IMPORTANCE The hallmark of HIV infection is a gradual depletion of CD4 T cells, with a progressive decline of host immunity. How CD4 T cells are depleted in individuals with active and virus-suppressed HIV infection remains unclear. In this study, we employed a cellular model of HIV infection to characterize the mechanisms underlying CD4 T-cell destruction by analyzing the chromosome end (telomere) DNA damage response (DDR) and cellular apoptosis in a T-cell line (highly permissive SupT1 cells), as well as in primary CD4 T cells with active or drug-suppressed HIV infection. We demonstrated that HIV-induced telomeric DDR plays a critical role in inducing telomere loss, premature cell aging, and CD4 T-cell apoptosis or depletion via dysregulation of the PI3K/ATM pathways. This study sheds new light on the molecular mechanisms of telomeric DDR and its role in CD4 T-cell homeostasis during HIV infection.

RILA blood biomarker as a predictor of radiation-induced sarcoma in a matched cohort study.

PurposeRadiation-induced sarcoma (RIS) is a rare but serious event. Its occurrence has been discussed during the implementation of new radiation techniques and justified appropriate radioprotection requirements. New approaches targeting intrinsic radio-sensitivity have been described, such as radiation-induced CD8 T-lymphocyte apoptosis (RILA) able to predict late radio-induced toxicities. We studied the role of RILA as a predisposing factor for RIS as a late adverse event following radiation therapy (RT).Patients and methodsIn this prospective biological study, a total of 120 patients diagnosed with RIS were matched with 240 control patients with cancer other than sarcoma, for age, sex, primary tumor location and delay after radiation. RILA was prospectively assessed from blood samples using flow cytometry.ResultsThree hundred and forty-seven patients were analyzed (118 RIS patients and 229 matched control patients). A majority (74%) were initially treated by RT for breast cancer. The mean RT dose was comparable with a similar mean (± standard deviation) for RIS (53.7 ± 16.0 Gy) and control patients (57.1 ± 15.1 Gy) (p = .053). Median RILA values were significantly lower in RIS than in control patients with respectively 18.5% [5.5–55.7] and 22.3% [3.8–52.2] (p = .0008). Thus, patients with a RILA >21.3% are less likely to develop RIS (p < .0001, OR: 0.358, 95%CI [0.221–0.599].ConclusionRILA is a promising indicator to predict an individual risk of developing RIS. Our results should be followed up and compared with molecular and genomic testing in order to better identify patients at risk. A dedicated strategy could be developed to define and inform high-risk patients who require a specific approach for primary tumor treatment and long term follow-up.

Absence of correlation between radiation-induced CD8 T-lymphocyte apoptosis and sequelae in patients with prostate cancer accidentally overexposed to radiation.

Purpose454 patients with prostate adenocarcinoma were accidentally overexposed to radiation in Epinal hospital, France, between August 1999 and January 2007. We aimed toevaluate whether radiation-induced CD4 or CD8 T-lymphocyte apoptosis (RILA) correlates with the severity of radiation toxicity.MethodsBetween 2007 and 2013, all patients who received more than 108% of the prescribed radiation dose, after correction of the treatment plan, were convened, and blood was sampled at 6-months follow-up. Maximal Digestive toxicity (MDT) and maximal urinary toxicity (MUT) were graded using the Common Terminology Criteria for Adverse Events (NCI-CTCAE) v3.0 scale. RILA was assessed using flow cytometry.Results245 patients were included in our study. After a median follow-up of 4.8 years, the MDT and MUT reached grade 3-4 in 37 patients and 56 patients, respectively. Patients with prostatectomy exhibited a statistically higher grade of MUT compared with those treated with definitive radiotherapy (p=0.03). The median RILA values were 11.8% and 15.3% for CD4 and CD8 T-lymphocytes, respectively. We found no significant correlation between CD4 or CD8 RILA and either MDT or MUT.ConclusionRILA does not correlate with the inter-individual variation in MDT or MUT in the largest cohort of patients overexposed to radiation. The magnitude of the overdosage probably overrides biological predictors of toxicity, including individual radiosensitivity.

Tumor-associated neutrophils induce apoptosis of non-activated CD8 T-cells in a TNFα and NO-dependent mechanism, promoting a tumor-supportive environment

ABSTRACTThe role of neutrophils in tumor progression has become in recent years a subject of growing interest. Tumor-associated neutrophils (TANs), which constitute an important portion of the tumor microenvironment, promote immunosuppression in advanced tumors by modulating the proliferation, activation and recruitment of a variety of immune cell types. Studies which investigated the consequences of manipulating TAN polarization suggest that the impact of these neutrophils on tumor progression is considerably mediated by and dependent on the presence of CD8 T-cells. It has been previously shown that granulocytic myeloid regulatory cells, i.e. TANs and granulocytic myeloid-derived suppressor cells (G-MDSCs) are capable of suppressing CD8 T-cell proliferation and affect their activation. In the current study, we find that in addition, TANs isolated from different models of murine cancer promote immunosuppression by strongly inducing CD8 T-cell apoptosis. We demonstrate that the TNFα pathway in TANs is critical for the induction of apoptosis, and that the mechanism through which apoptosis is induced involves the production of NO, but not ROS. In the absence of pre-activation, TANs are capable of activating CD8 T-cells, but specifically induce the apoptosis of non-activated CD8+CD69− cells. Despite this contradictive effect on T-cell function, we show in vivo that TANs suppress the anti-tumor effect of CD8 T-cells and abolish their ability to delay tumor growth. Our results add another important layer on the understanding of the possible mechanisms by which TANs regulate the anti-tumor immune response mediated by CD8 T-cells, therefore promoting a tumor-supportive environment.

Hepatic fibrosis and immune phenotype vary by HCV viremia in HCV/HIV co-infected subjects: A Women's interagency HIV study.

HCV and HIV independently lead to immune dysregulation. The mechanisms leading to advanced liver disease progression in HCV/HIV coinfected subjects remain unclear.In this cross-sectional study, we assessed the association of HCV viremia, liver fibrosis, and immune response patterns in well-characterized HIV phenotypes: Elite controllers (Elites), HIV controlled (ARTc), and HIV uncontrolled (ARTuc) matched by age and race. Groups were stratified by HCV RNA status. Regulatory T-cell frequencies, T-cell activation (HLADR+CD38+), apoptosis (Caspase-3+), and intracellular cytokines (interferon-γ, IL-2, IL-17) were assessed using multiparametric flow-cytometry. Liver fibrosis was scored by AST to platelet ratio index (APRI).We found liver fibrosis (APRI) was 50% lower in Elites and ARTc compared to ARTuc. Higher liver fibrosis was associated with significantly low CD4+ T cell counts (P < 0.001, coefficient r = -0.463). Immune activation varied by HIV phenotype but was not modified by HCV viremia. HCV viremia was associated with elevated CD8 T-cell Caspase-3 in Elites, ARTuc, and HIV- except ARTc. CD8 T-cell Caspase-3 levels were significantly higher in HCV RNA+ Elites (P = 0.04) and ARTuc (P = 0.001) and HIV- groups (P = 0.02) than ARTc. Importantly, ARTuc HCV RNA+ had significantly higher CD4 T-cell interleukin-17 levels than ARTuc HCV RNA- (P = 0.005).HIV control was associated with lower liver fibrosis in HCV/HIV co-infected women. HCV viremia is associated with an inflammatory CD4 TH-17 phenotype in absence of HIV control and higher frequency of pro-apoptosis CD8 T-cells critical to avert progression of HIV and HCV disease that is attenuated in ART controllers. Elite controllers with HCV viremia are more prone to CD8 T-cell apoptosis than ART controllers, which could have negative consequences over time, highlighting the importance of ART control in HCV/HIV coinfected individuals.

Correlation between radio-induced lymphocyte apoptosis measurements obtained from two French centres

Purpose of the researchIn the era of modern treatment delivery, increasing the dose delivered to the target to improve local control might be modulated by the patient's intrinsic radio-sensitivity. A predictive assay based on radio-induced lymphocyte apoptosis quantification highlighted the significant correlation between CD4 and CD8 T-lymphocyte apoptosis and grade 2 or 3 radiation-induced late toxicities. By conducting this assay at several technical platforms, the aim of this study was to demonstrate that radio-induced lymphocyte apoptosis values obtained from two different platforms were comparable. Materials and methodsFor 25 patients included in the PARATOXOR trial running in Dijon the radio-induced lymphocyte apoptosis results obtained from the laboratory of Montpellier (IRCM, Inserm U1194, France), considered as the reference (referred to as Lab 1), were compared with those from the laboratory located at the Institut de cancérologie de Lorraine (ICL, France), referred to as Lab 2. Different statistical methods were used to measure the agreement between the radio-induced lymphocyte apoptosis data from the two laboratories (quantitative data). The Bland–Altman plot was used to identify potential bias. ResultsAll statistical tests demonstrated good agreement between radio-induced lymphocyte apoptosis values obtained from both sites and no major bias was identified. ConclusionsSince radio-induced lymphocyte apoptosis values, which predict tolerance to radiotherapy, could be assessed by two laboratories and showed a high level of robustness and consistency, we can suggest that this assay be extended to any laboratories that use the same technique.

Abstract P3-12-18: Radiation-induced CD8 T-lymphocyte apoptosis as a predictor of late toxicity after radiotherapy: Results of the prospective multicenter French trial

Abstract Purpose/Objective(s): We and others showed in retrospective and monocentric studies that radiation-induced CD8-lymphocyte apoptosis (RILA) can significantly predict differences in late toxicity between individuals and can be used as a rapid screening for potential hyper-reactive patients to radiation therapy (RT). We present here the clinical results of the prospective multicenter French trial (NCT00893035) evaluating the predictive role of RILA as a predictor of late effects after RT. Materials/Methods: A total of 502 consenting breast-cancer patients (pts) treated by conservative surgery and adjuvant RT were included by 10 French centers. Lymphocytes apoptosis was assessed before RT by associated condensation of DNA. The incidence of late toxicities was obtained using CTCAEv3.0 grading scale. Complication-free survival (CFS) and complication-relapse-free survival (CRFS) curves were estimated by the Kaplan-Meier method. The log-rank test was used to identify significant categorical variables for each of the survival curves. Cox model was used for multivariate analysis. Results: Four hundred and fifty-four pts (90.4%) were included in the final analysis (clinical, biological and dosimetric data available). One hundred and eight pts (24%) received both whole breast (WB) and nodal irradiation (NI). A boost dose of 10-16 Gy was given in 448 pts (99%). Adjuvant hormonotherapy (tamoxifen or aromatase inhibitor) was delivered to 346 pts (76%). Three categories of absolute change in the percent CD8 cells in apoptosis before and after exposure to 8-Gy in vitro RT were constructed around the 33 percent quantiles, &amp;lt;12%, 12-20%, and &amp;gt;20%. In a median follow-up period of 38.5 months, grade 2 and 3 late fibrosis was observed in 54 (12%) and 3 (0.7%) pts, respectively. A decreased percentage of grade 2 or more late toxicity was observed for increasing values of CD8 apoptosis (p=0.001). No grade 3 late toxicity was observed for patients with RILA ≥12%. The 3-year CFS rates were significantly lower for patients with low levels of CD8 radiation-induced apoptosis, 79% (95% confidence interval [CI]: 72–85%), 90% (95% CI: 84–94%), and 93% (95% CI: 87–96%) for CD8 &amp;lt;12%, 12–20%, and &amp;gt;20%, respectively (p=0.001). Similar results were observed for the CRFS rates (p&amp;lt;0.001). In multivariate analyses, prognostic factors for CFS were RILA&amp;lt;12% (p=0.001), smoking history (p&amp;lt;0.001), and adjuvant hormonal treatment (p=0.008). Negative predictive value for grade 2 or more toxicity was equal to 83% for CD8 &amp;gt;20% and positive predictive value was equal to 22% for CD8 &amp;lt;12% where the overall prevalence of grade 2 or more late side effects was estimated at 14%. Conclusion: RILA significantly predicts differences in radiation-induced late toxicity between individuals. This study validates the use of RILA as a rapid screening for potential hyper-reactive pts to radiotherapy. Citation Format: Hennequin C, Azria D, Riou O, Castan F, Coelho M, Nguyen TD, Peignaux K, Lemanski C, Lagrange J-L, Kirova Y, Lartigau E, Belkacemi Y, Bourgier C, Noel G, Clippe S, Mornex F, Kramar A, Pèlegrin A, Ozsahin M. Radiation-induced CD8 T-lymphocyte apoptosis as a predictor of late toxicity after radiotherapy: Results of the prospective multicenter French trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-12-18.

Radiation Induced CD8 T-Lymphocyte Apoptosis as a Predictor of Late Toxicity After Radiation Therapy: Results of the Prospective Multicenter French Trial

Radiation Induced CD8 T-Lymphocyte Apoptosis as a Predictor of Late Toxicity After Radiation Therapy: Results of the Prospective Multicenter French Trial

Radiation-induced CD8 T-lymphocyte Apoptosis as a Predictor of Breast Fibrosis After Radiotherapy: Results of the Prospective Multicenter French Trial

BackgroundMonocentric cohorts suggested that radiation-induced CD8 T-lymphocyte apoptosis (RILA) can predict late toxicity after curative intent radiotherapy (RT). We assessed the role of RILA as a predictor of breast fibrosis (bf+) after adjuvant breast RT in a prospective multicenter trial. MethodsA total of 502 breast-cancer patients (pts) treated by conservative surgery and adjuvant RT were recruited at ten centers. RILA was assessed before RT by flow cytometry. Impact of RILA on bf+ (primary endpoint) or relapse was assessed using a competing risk method. Receiver–operator characteristic (ROC) curve analyses were also performed in intention to treat. This study is registered with ClinicalTrials.gov, number NCT00893035 and final analyses are presented here. FindingsFour hundred and fifty-six pts (90.8%) were included in the final analysis. One hundred and eight pts (23.7%) received whole breast and node irradiation. A boost dose of 10–16Gy was delivered in 449 pts (98.5%). Adjuvant hormonotherapy was administered to 349 pts (76.5%). With a median follow-up of 38.6months, grade ≥2 bf+ was observed in 64 pts (14%). A decreased incidence of grade ≥2 bf+ was observed for increasing values of RILA (p=0.012). No grade 3 bf+ was observed for patients with RILA ≥12%. The area under the ROC curve was 0.62. For cut-off values of RILA ≥20% and <12%, sensitivity and specificity were 80% and 34%, 56% and 67%, respectively. Negative predictive value for grade ≥2 bf+ was equal to 91% for RILA ≥20% and positive predictive value was equal to 22% for RILA <12% where the overall prevalence of grade ≥2 bf+ was estimated at 14%. A significant decrease in the risk of grade ≥2 bf+ was found if patients had no adjuvant hormonotherapy (sHR=0.31, p=0.007) and presented a RILA ≥12% (sHR=0.45, p=0.002). InterpretationRILA significantly predicts the risk of breast fibrosis. This study validates the use of RILA as a rapid screening test before RT delivery and will change definitely our daily clinical practice in radiation oncology. FundingThe French National Cancer Institute (INCa) through the “Program Hospitalier de Recherche Clinique (PHRC)”.

Co-infection With Hepatitis C Virus Is Not Associated With Time to immunological Failure in Females With HIV on Antiretroviral Therapy

Introduction: As a consequence of shared routes of transmission, over 30% of Human Immunodeficiency Virus (HIV) infected individuals are co-infected with Hepatitis C virus (HCV). In the United States, 150 000 to 300 000 persons are infected with both HIV and HCV. Several studies have suggested that hastened immunological deterioration occurs in co-infected persons, but others have shown no effect in patients with Antiretroviral therapy (ART), especially among women. Consequently, whether HCV affects the course of HIV infection remains controversial. The objective of this study was to compare the rate of time to immunological failure in HIV mono-infected and HCV/HIV co-infected females on ART. Methods: This was a retrospective, observational cohort study of HIV positive female patients receiving care at the University of Louisville HIV Clinic between January 2006 and December 2012. Western Blot and ELISA made the diagnosis of HIV and HCV infections, respectively. Data on compliance with ART and CD4 cell count was collected by reviewing Electronic Medical Records. Immunological failure was define as a drop of 20% in the CD4 cell count of the prior year. The median absolute CD4 cell count was calculated annually. The mean of those medians was then calculated across the study period. Student's t test was used to evaluate the CD4 means between each group. Kaplan-Meier survival curves assessed the statistical difference in the time to immunologic failure between the HIV mono-infected and the HCV/HIV co-infected groups. Results: A total of 315 HIV positive females were included in the study. Of those, 58 (18%) were HCV positive. There was not statistical difference on ART compliance (p=0.737). The mean (SD) CD4 count across the entire study period was 409 (73) for the HCV/HIV co-infected group versus 411 (51) for the HIV mono-infected group, (P=0.968). The Kaplan-Meier survival curves for immunologic failure showed no difference between mono-infected versus co-infected patients. (P=0.953).Table 1: Baseline CharacteristicsFigure 1Conclusion: This study supports the concept that HCV co-infection is not associated with time to immunological failure in HIV positive females. HCV has been found to enhance CD4 T-cell apoptosis, however this effect is rapidly lost under antiretroviral therapy. It has been postulated that Protease Inhibitors, a component of all ART, block cellular apoptosis, thus, an effective antiretroviral therapy may limit the impact of HCV infection on the immunological course of HIV disease.

Galectin-9 ameliorates respiratory syncytial virus-induced pulmonary immunopathology through regulating the balance between Th17 and regulatory T cells

Respiratory syncytial virus (RSV) infections are characterized by lung inflammation, mucus hypersecretion, and hyperresponsiveness. CD4+ T cells play a pivotal role in the development of RSV-induced lung pathology. Thus targeting the activation of CD4+ T cell subsets and enhancing regulatory functions of CD4+ T cells could be an effectively therapeutic approach. In the present study, we showed that RSV-induced lung inflammation can be suppressed by lectin family member Galectin-9 (Gal-9), which is identified as a T-cell immunoglobulin- and mucindomain-containing molecule-3 (Tim-3) ligand (L) and the Gal-9/Tim-3 interaction acts as a specific inhibitor of T helper(Th)1 and Th17 immune responses. Tim-3 expression was up-regulated in RSV-infected mice compared to non-infected controls. Therefore, we constructed a recombinant adenoviral (rAAV) 9-Gal-9 adenoviral plasmid, and administered it intranasally into RSV-infected mice for five times at every other day until day 8 post-infection. We found that Gal-9 administration significantly decreased viral load, inhibited mucus production, and diminished severity of lung pathology which were all induced by RSV infection. Complicated mechanisms were involved in these inhibitory effects, including inhibition of Th17 cell production, induction of regulatory cell expansion, as well as alteration of CD8 T-cell apoptosis. Our findings suggest that regulating the function of the Gal-9/Tim-3 pathway will be an effective and safe approach to treat RSV infection in lungs.

Surface-bound Tat inhibits antigen-specific CD8+ T-cell activation in an integrin-dependent manner.

The identification of still unrevealed mechanisms affecting the anti-HIV CD8 T-cell response in HIV-1 infection. Starting from the observation that anti-Tat immunization is associated with improved CD8 T-cell immunity, we developed both in-vitro and ex-vivo assays to characterize the effects of extra-cellular Tat on the adaptive CD8 T-cell response. The effects of Tat on CD8 T-cell activation were assayed using CD8 T-cell clones specific for either cellular (MART-1) or viral (HIV-1 Nef) antigens, and HIV-1 Gag-specific CD8 T cells from HIV-1 patients. The interaction between CD8 T lymphocytes and immobilized Tat, but not its soluble form, inhibits peptide-specific CD8 T-lymphocyte activation. The inhibition does not depend on Tat trans-activation activity, but on the interaction of the Tat RGD domain with α5β1 and αvβ3 integrins. Impaired CD8 T-cell activation was also observed in cocultures of CD8 T cells with HIV-1-infected cells. Anti-Tat Abs abrogate the inhibitory effect, consistently with the evidence that extracellular Tat accumulates on the cell membrane of virus-producing cells. The Tat-induced inhibition of cell activation associates with increased apoptosis of CD8 T cells. Finally, the inhibition of cell activation also takes place in Gag-specific CD8 T lymphocytes from HIV-1-infected patients. Our results support the idea that CD8 T-cell apoptosis induced by surface-bound extracellular Tat can contribute to the dysregulation of the CD8 T-cell adaptive response against HIV as well as other pathogens present in AIDS patients.

Human Hepatic Stellate Cells Inhibit T-Cell Response Through B7-H1 Pathway

The liver is an immunologic privileged organ; liver allografts are accepted across major histocompatibility complex barriers in many species. However, hepatocyte transplants are acutely rejected, suggesting a role for liver nonparenchymal cells in regulating the immunoresponse. We have shown potent immunoregulatory activity of hepatic stellate cells (HSCs) in mice. The aim of this study was to examine the immunoregulatory activity of human HSCs. HSCs were isolated from normal human livers for analyses of their impact on T-cell response. HSCs expressed low HLA-DR and costimulatory molecules CD40 and CD80 but constitutively expressed high levels of CD54. Interferon-γ stimulated HSCs to express B7-H1 in a dose-dependent manner and produce the suppressive cytokines interleukin-6, interleukin-10, and transforming growth factor-β but did not affect expression of HLA-DR, CD40, and CD80. Human HSCs did not stimulate allogeneic T-cell proliferative response, indicating that they are not professional antigen-presenting cells. HSCs markedly inhibited T-cell response elicited by either allogeneic antigen-presenting cells or CD3/CD28 beads, which was associated with increases in activated CD4 and CD8 T-cell apoptosis. Addition of anti-B7-H1 blocking antibody significantly reversed the inhibitory effect. Human HSCs demonstrate potent immunoregulatory activity via B7-H1-mediated induction of apoptosis in activated T cells. Understanding of the involved mechanisms may lead to development of novel therapeutic approaches for treatment of liver diseases.