Human and Viral microRNA Expression in Acute and Chronic HIV Infections.

Human and viral microRNAs (miRNAs) are involved in the regulation of gene transcription, and the establishment of their profiles in acute (AHI) and chronic (CHI) HIV infections may shed light on the pathogenetic events related to different phases of HIV disease. Next-generation sequencing (NGS) of miRNA libraries was performed, and the reads were used to analyze miRNA differential expression in the plasma with AHI and CHI. Functional analysis was then undertaken to investigate the biological processes characterizing the two phases of HIV infection. Except for hsa-miR-122-5p, which was found in 3.39% AHI vs. 0.18% CHI, the most represented human miRNAs were similarly represented in AHI and CHI. However, when considering the overall detected miRNAs in AHI and CHI, 15 displayed differential expression (FDR p < 0.05). Functional analysis identified 163 target mRNAs involved in promoting angiogenesis activation in AHI versus CHI through the action of hsa-miR10b-5p, hsa-miR1290, hsa-miR1-3p, and hsa-miR296-5p. The viral miRNAs detected, all belonging to herpesviruses, accounted for only 0.014% of total reads. The present data suggest that AHI patients exhibit strong innate immune activation through the upregulation of hsa-miR-122-5p and early activation of angiogenesis. More specific investigations are needed to study the role of viral miRNAs in HIV pathogenesis.

Rapid ART initiation with bictegravir/emtricitabine/tenofovir alafenamide in individuals presenting with advanced HIV disease (Rainbow study).

BACKGROUND: A rapid ART initiation approach can be beneficial in people with advanced HIV disease, in consideration of their high morbidity and mortality. The aim of our study was to evaluate the feasibility, efficacy and safety of rapid ART start with BIC/FTC/TAF in this setting. METHODS: Pilot, single-centre, single-arm, prospective, phase IV clinical trial conducted in a tertiary Italian hospital. Thirty ART-naïve people presenting with advanced HIV-1 diagnosis (defined as the presence of an AIDS-defining event and/or CD4 cell count <200 µL), were enrolled. Main exclusion criteria were active tuberculosis, cryptococcosis and pregnant/breastfeeding women. BIC/FTC/TAF was started within 7 days from HIV diagnosis. The primary endpoint was clinical or virologic failure (VF). Immunological parameters, safety, feasibility, neurocognitive performances and patient-reported outcomes were assessed as well. RESULTS: Over the study period, 40 (34%) of 116 patients diagnosed with HIV infection at INMI Spallanzani had advanced disease, of whom 30 (26%) were enrolled. The proportion of participants with HIV-RNA <50 cp/mL was 9/30 (30%) at week (w) 4, 19/30 (63%) at w12, 24/30 (80%) at w24, 23/30 (77%) at w36 and 27/30 (90%) at w48. Two unconfirmed VF occurred. No ART discontinuation due to toxicity or VF was observed. No ART modification was performed based on the review of genotype and no mutations for the study drugs were detected. Mean CD4 cells count changed by 133 cells/µL at BL to 309 cells/µL at w 48 and 83% of participants had a CD4 > 200 cells/µL at w 48. Two participants developed IRIS and one was diagnosed with disseminated TB and needed an ART switch. INTERPRETATIONS: Our results support the feasibility, efficacy and safety of BIC/FTC/TAF as a rapid ART strategy in patients with advanced HIV disease.

Kinetics of TTV Loads in Peripheral Blood Mononuclear Cells of Early Treated Acute HIV Infections.

Torquetenovirus (TTV) is the most abundant component of the human blood virome and its replication is controlled by a functioning immune system. In this study, TTV replication was evaluated in 21 people with acute HIV infection (AHI) and immune reconstitution following antiretroviral therapy (ART). PBMC-associated TTV and HIV-1 DNA, as well as plasma HIV-1 RNA, were measured by real-time PCR. CD4 and CD8 differentiation, activation, exhaustion, and senescence phenotypes were analyzed by flow cytometry. Thirteen healthy donors (HD) and twenty-eight chronically infected HIV individuals (CHI), late presenters at diagnosis, were included as control groups. TTV replication in AHI seems to be controlled by the immune system being higher than in HD and lower than in CHI. During ART, a transient increase in TTV DNA levels was associated with a significant perturbation of activation and senescence markers on CD8 T cells. TTV loads were positively correlated with the expansion of CD8 effector memory and CD57+ cells. Our results shed light on the kinetics of TTV replication in the context of HIV acute infection and confirm that the virus replication is strongly regulated by the modulation of the immune system.

Development and validation of a nanoplate-based digital PCR assay for absolute MPXV quantification.

Quantification of mpox virus (MPXV) across different human body anatomical sites can provide insights about the most likely transmission routes, so methods able to release absolute and exact quantitative values of MPXV DNA are crucial. Here, we optimized a new QIAcuity digital PCR (dPCR) protocol for the detection and quantification of MPXV DNA in clinical samples and assessed the performance of the assay by comparing the results obtained in 144 biological samples with those resulting from the use of an in-house real-time PCR (qPCR). Overall, the concordance between the two assays was 95%, with samples identified concordantly as MPXV DNA positive and having a mean number of copies per µl of 1708 (95% CI: 107-2830 copies/µl). The remaining samples gave discordant results, with 5 out of 7 detected with the QIAcuity dPCR assay but not with the in-house qPCR. MPXV DNA levels measured by QIAcuity dPCR were strongly correlated with the Ct values detected by in-house qPCR and with those detected by another dPCR assay previously developed in our laboratories. The QIAcuity dPCR assay may be a robust and easy-to-perform method for MPXV DNA quantification in several biological samples.

Treatment with valacyclovir during pregnancy for prevention of congenital cytomegalovirus infection: a real-life multicenter Italian observational study.

BACKGROUND: Valacyclovir is the only treatment demonstrated to be effective for the prevention of vertical transmission of cytomegalovirus within a clinical randomized, placebo-controlled trial and has been reimbursed by the Italian National Health System since December 2020. OBJECTIVE: This study reported the results of a real-life Italian multicenter observational study on cytomegalovirus infection in pregnancy evaluating the effect of the introduction of valacyclovir in the clinical practice for the prevention of vertical transmission of cytomegalovirus. STUDY DESIGN: The outcomes of women who received valacyclovir treatment and their fetuses or newborns were compared with those of a retrospective cohort observed between 2010 and 2020 who did not receive the antiviral treatment. The inclusion criterion was the diagnosis of cytomegalovirus primary infection occurring in the periconceptional period or up to 24 weeks of gestation. The primary outcome was the transmission by the time of amniocentesis. The secondary outcomes were termination of pregnancy, transmission at birth, symptomatic infection at birth, and a composite outcome (termination of pregnancy or transmission at birth). RESULTS: A total of 447 pregnant women from 10 centers were enrolled, 205 women treated with valacyclovir (called the valacyclovir group, including 1 twin pregnancy) and 242 women not treated with valacyclovir (called the no-valacyclovir group, including 2 twin pregnancies). Valacyclovir treatment was significantly associated with a reduction of the diagnosis of congenital cytomegalovirus infection by the time of amniocentesis (weighted odds ratio, 0.39; 90% confidence interval, 0.22-0.68; P=.005; relative reduction of 61%), termination of pregnancy (weighted odds ratio, 0.36; 90% confidence interval, 0.17-0.75; P=.0021; relative reduction of 64%), symptomatic congenital cytomegalovirus infection at birth (weighted odds ratio, 0.17; 90% confidence interval, 0.06-0.49; P=.006; relative reduction of 83%). The treatment had no significant effect on the rate of diagnosis of congenital cytomegalovirus infection at birth (weighted odds ratio, 0.85; 90% confidence interval, 0.57-1.26; P=.500), but the composite outcome (termination of pregnancy or diagnosis of congenital cytomegalovirus infection at birth) occurred more frequently in the no-valacyclovir group (weighted odds ratio, 0.62; 90% confidence interval, 0.44-0.88; P=.024). Of note, the only symptomatic newborns with congenital cytomegalovirus infection in the valacyclovir group (n=3) were among those with positive amniocentesis. Moreover, 19 women (9.3%) reported an adverse reaction to valacyclovir treatment, classified as mild in 17 cases and moderate in 2 cases. Lastly, 4 women (1.9%) presented renal toxicity with a slight increase in creatinine level, which was reversible after treatment suspension. CONCLUSION: Our real-life data confirm that valacyclovir significantly reduces the rate of congenital cytomegalovirus diagnosis at the time of amniocentesis with a good tolerability profile and show that the treatment is associated with a reduction of termination of pregnancy and symptomatic congenital cytomegalovirus infection at birth.

Kinetics of viral DNA in body fluids and antibody response in patients with acute Monkeypox virus infection.

We report the follow-up laboratory investigation of three MPXV cases infected in May-June 2022 from diagnosis to disease resolution, monitoring viral shedding in different body fluids and antibody kinetics. Out of 138 non-lesion samples, viral DNA was found in 92.3% saliva, 85.7% semen, 86.2% oropharyngeal swabs, 51.7% plasma, 46.1% stool, and 9.5% urine samples. Viral load quantified by digital PCR widely varied, but tend to be higher in oropharyngeal swabs, saliva, and stool. Replication competent virus was recovered from four out of seventeen samples, including 1 saliva, 1 oropharyngeal swabs, 1 semen, and 1 stool. The analysis of the antibody kinetics revealed that IgM, IgA, and IgG antibodies were detected within two weeks post-symptoms onset for all three patients, with IgG detected early on at day 4-8 and IgM and IgA showing lower titers along the time frame of the study. Antibody levels increased during the second week of illness with IgG reaching high titers.

Non-B subtypes account for a large proportion of clustered primary HIV-1 infections in Italy.

OBJECTIVES AND DESIGN: Using pol sequences obtained for routine resistance testing, we characterised the molecular patterns of HIV-1 transmission and factors associated with being part of a transmission cluster among individuals who in 2008-2014 presented with primary HIV-1 infection (PHI) at 11 urban centres across Italy. METHODS: Pol sequences were obtained by Sanger sequencing. Transmission clusters were identified by phylogenetic analysis (maximum likelihood method, confirmed by Bayesian analysis). Multivariable logistic regression explored factors associated with a participant being part of a transmission cluster. RESULTS: The PHI cohort comprised 186 participants (159/186, 85.5% males) with median age 44 years, median CD4 count 464 cells/mm3 and median plasma HIV-1 RNA 5.6 log10 copies/mL. Drug resistance associated mutations were found in 16/186 (8.6%). A diversity of non-B subtypes accounted for 60/186 (32.3%) of all infections. A total of 17 transmission clusters were identified, including 44/186 (23.7%) participants. Each cluster comprised 2-6 sequences. Non-B subtypes accounted for seven clusters and 22/44 (50%) of clustered sequences. In multivariable logistic regression analysis, factors associated with being part of a transmission cluster comprised harbouring a non-B subtype (adjusted OR (adjOR) 2.28; 95% CI 1.03 to 5.05; p=0.04) and showing a lower plasma HIV-1 RNA (adjOR 0.80, 95% CI 0.64 to 0.99; p=0.04). CONCLUSIONS: There was a large contribution of diverse non-B subtypes to transmission clusters among people presenting with acute or recent HIV-1 infection in this cohort, illustrating the evolving dynamics of the HIV-1 epidemic in Italy, where subtype B previously dominated.

Intact provirus and integration sites analysis in acute HIV-1 infection and changes after one year of early antiviral therapy.

Background and objectives: HIV-1 provirus integration in host genomes provides a lifelong reservoir of virally infected cells. Although not able to generate viral progeny, the expression of defective proviruses has been associated with activation. Provirus integration may influence host gene transcription and shifts may occur during disease progression or antiretroviral therapy (ART). The study aimed to analyze intact/defective provirus and sites of provirus integration in acute infections: changes after 48 weeks of early therapy were also evaluated. Methods: DNA from peripheral blood lymphomonocytes of 8 acute HIV-1 infections at serodiagnosis (T0) and after 48 weeks of therapy (T1) was used to quantify intact and defective provirus by digital-droplet PCR and to analyze provirus integration sites, by next-generation sequencing of libraries derived from ligation-mediated PCR. Results: A high variability in the amount of intact proviral DNA was observed at both T0 and T1, in the different subjects. Although the ratio of intact/total proviral HIV-1 DNA did not dramatically change between T0 (8.05%) and T1 (9.34%), after early therapy both intact and total HIV-1 DNA declined significantly, p = 0.047 and p = 0.008, respectively. The median number of different (IQR) integration sites in human chromosomes/subject was 5 (2.25-13.00) at T0 and 4 (3.00-6.75) at T1. Of all the integration sites observed at T1, 64% were already present at T0. Provirus integration was observed in introns of transcriptionally active genes. Some sites of integration, among which the most represented was in the neuregulin 2 gene, were shared by different patients, together with the orientation of the insertion. Provirus integration was also observed in intergenic regions, with median (IQR) % of 15.13 (6.81-21.40) at T0 and 18.46 (8.98-22.18) at T1 of all read matches. Conclusions: In acute HIV-1 infection, the amount of intact proviral DNA in peripheral lymphomonocytes did not exceed 10% of total HIV-1 DNA, a percentage that was not substantially changed by early administrated ART. Provirus displayed a relatively small number of recurrent integration sites in introns of transcriptionally active genes, mainly related to cell-cycle control. Consideration should be given to therapeutic strategies able to target the cells harboring defective proviruses, that are not reached by conventional antiviral drugs, these potentially also impacting on replicative competent integrated provirus.

Virological and Immunological Outcomes of an Intensified Four-Drug versus a Standard Three-Drug Antiretroviral Regimen, Both Integrase Strand Transfer Inhibitor-Based, in Primary HIV Infection.

The optimal therapeutic approach for primary HIV infection (PHI) is still debated. We aimed to compare the viroimmunological response to a four- versus a three-drug regimen, both INSTI-based, in patients with PHI. This was a monocentric, prospective, observational study including all patients diagnosed with PHI from December 2014 to April 2018. Antiretroviral therapy (ART) was started, before genotype resistance test results, with tenofovir/emtricitabine and either raltegravir plus boosted darunavir or dolutegravir. Cumulative probability of virological suppression [VS] (HIV-1 RNA< 40 cp/mL), low-level HIV-1 DNA [LL-HIVDNA] (HIV-1 DNA < 200 copies/106PBMC), and CD4/CD8 ratio ≥1 were estimated using Kaplan−Meier curves. Factors associated with the achievement of VS, LL-HIVDNA, and CD4/CD8 ≥ 1 were assessed by a Cox regression model. We enrolled 144 patients (95.8% male, median age 34 years): 110 (76%) started a four-drug-based therapy, and 34 (24%) a three-drug regimen. Both treatment groups showed a comparable high probability of achieving VS and a similar probability of reaching LL-HIVDNA and a CD4/CD8 ratio ≥1 after 48 weeks from ART initiation. Higher baseline HIV-1 RNA and HIV-1 DNA levels lowered the chance of VS, whereas a better preserved immunocompetence increased that chance. Not statistically significant factors associated with LL-HIVDNA achievement were found, whereas a higher baseline CD4/CD8 ratio predicted the achievement of immune recovery. In PHI patients, the rapid initiation of either an intensified four-drug or a standard three-drug INSTI-based regimen showed comparable responses in terms of VS, viral reservoir size, and immunological recovery.

External quality assessment of HIV-1 DNA quantification assays used in the clinical setting in Italy.

Total cell-associated HIV-1 DNA is a surrogate marker of the HIV-1 reservoir, however, certified systems for its quantification are not available. The Italian HIV DNA Network was launched to validate HIV-1 DNA quantification methods in use at University and Hospital labs. A quality control panel including HIV-1 DNA standards, reconstructed blood samples (RBSs) and DNA from different HIV-1 subtypes was blindly tested by 12 participating labs by quantitative real-time PCR (n = 6), droplet digital PCR (n = 3) or both (n = 3). The median 95% hit rate was 4.6 (3.7-5.5) copies per test and linearity in the tested range was excellent (R2 = 1.000 [1.000-1.000]). The median values obtained across labs were 3,370 (2,287-4,245), 445 (299-498), 59 (40-81) and 7 (6-11) HIV-1 DNA copies, for the 3,584, 448, 56 and 7-copy standards, respectively. With RBSs, measured values were within twofold with respect to the median in two thirds of cases. HIV-1 subtypes were missed (CRF01_AE by 3 labs) or underestimated by > 1 log (subtypes A, C, D, F by one lab; CRF01_AE by one lab; CRF02_AG by one lab). The overall performance was excellent with HIV-1 DNA standards, however detection of different HIV-1 subtypes must be improved.

Analysis of HIV quasispecies and virological outcome of an HIV D+/R+ kidney-liver transplantation.

INTRODUCTION: Transplantation among HIV positive patients may be a valuable therapeutic intervention. This study involves an HIV D+/R+ kidney-liver transplantation, where PBMC-associated HIV quasispecies were analyzed in donor and transplant recipients (TR) prior to transplantation and thereafter, together with standard viral monitoring. METHODS: The donor was a 54 year of age HIV infected woman: kidney and liver recipients were two HIV infected men, aged 49 and 61. HIV quasispecies in PBMC was analyzed by ultra-deep sequencing of V3 env region. During TR follow-up, plasma HIV-1 RNA, HIV-1 DNA in PBMC, analysis of proviral integration sites and drug-resistance genotyping were performed. Other virological and immunological monitoring included CMV and EBV DNA quantification in blood and CD4 T cell counts. RESULTS: Donor and TR were all ART-HIV suppressed at transplantation. Thereafter, TR maintained a nearly suppressed HIV-1 viremia, but HIV-1 RNA blips and the increase of proviral integration sites in PBMC attested some residual HIV replication. A transient peak in HIV-1 DNA occurred in the liver recipient. No major changes of drug-resistance genotype were detected after transplantation. CMV and EBV transient reactivations were observed only in the kidney recipient, but did not require specific treatment. CD4 counts remained stable. No intermixed quasispecies between donor and TR was observed at transplantation or thereafter. Despite signs of viral evolution in TR, HIV genetic heterogeneity did not increase over the course of the months of follow up. CONCLUSIONS: No evidence of HIV superinfection was observed in the donor nor in the recipients. The immunosuppressive treatment administrated to TR did not result in clinical relevant viral reactivations.

Results of an interventional HIV testing programme in the context of a mpox (formerly monkeypox) vaccination campaign in Latium Region, Italy, August to October 2022.

HIV testing was offered to 2,185 people receiving mpox (formerly monkeypox) vaccination, who reported not being HIV positive. Among them 390 were current PrEP users, and 131 had taken PrEP in the past. Of 958 individuals consenting testing, six were newly diagnosed with HIV. Two patients had symptomatic primary HIV infection. None of the six patients had ever taken PrEP. Mpox vaccination represents an important opportunity for HIV testing and counselling about risk reduction and PrEP.

Multi-omics approach to COVID-19: a domain-based literature review.

BACKGROUND: Omics data, driven by rapid advances in laboratory techniques, have been generated very quickly during the COVID-19 pandemic. Our aim is to use omics data to highlight the involvement of specific pathways, as well as that of cell types and organs, in the pathophysiology of COVID-19, and to highlight their links with clinical phenotypes of SARS-CoV-2 infection. METHODS: The analysis was based on the domain model, where for domain it is intended a conceptual repository, useful to summarize multiple biological pathways involved at different levels. The relevant domains considered in the analysis were: virus, pathways and phenotypes. An interdisciplinary expert working group was defined for each domain, to carry out an independent literature scoping review. RESULTS: The analysis revealed that dysregulated pathways of innate immune responses, (i.e., complement activation, inflammatory responses, neutrophil activation and degranulation, platelet degranulation) can affect COVID-19 progression and outcomes. These results are consistent with several clinical studies. CONCLUSIONS: Multi-omics approach may help to further investigate unknown aspects of the disease. However, the disease mechanisms are too complex to be explained by a single molecular signature and it is necessary to consider an integrated approach to identify hallmarks of severity.

Rationale and Criteria for a COVID-19 Model Framework.

Complex systems are inherently multilevel and multiscale systems. The infectious disease system is considered a complex system resulting from the interaction between three sub-systems (host, pathogen, and environment) organized into a hierarchical structure, ranging from the cellular to the macro-ecosystem level, with multiscales. Therefore, to describe infectious disease phenomena that change through time and space and at different scales, we built a model framework where infectious disease must be considered the set of biological responses of human hosts to pathogens, with biological pathways shared with other pathologies in an ecological interaction context. In this paper, we aimed to design a framework for building a disease model for COVID-19 based on current literature evidence. The model was set up by identifying the molecular pathophysiology related to the COVID-19 phenotypes, collecting the mechanistic knowledge scattered across scientific literature and bioinformatic databases, and integrating it using a logical/conceptual model systems biology. The model framework building process began from the results of a domain-based literature review regarding a multiomics approach to COVID-19. This evidence allowed us to define a framework of COVID-19 conceptual model and to report all concepts in a multilevel and multiscale structure. The same interdisciplinary working groups that carried out the scoping review were involved. The conclusive result is a conceptual method to design multiscale models of infectious diseases. The methodology, applied in this paper, is a set of partially ordered research and development activities that result in a COVID-19 multiscale model.

Molecular Transmission Dynamics of Primary HIV Infections in Lazio Region, Years 2013-2020.

Molecular investigation of primary HIV infections (PHI) is crucial to describe current dynamics of HIV transmission. Aim of the study was to investigate HIV transmission clusters (TC) in PHI referred during the years 2013-2020 to the National Institute for Infectious Diseases in Rome (INMI), that is the Lazio regional AIDS reference centre, and factors possibly associated with inclusion in TC. These were identified by phylogenetic analysis, based on population sequencing of pol; a more in depth analysis was performed on TC of B subtype, using ultra-deep sequencing (UDS) of env. Of 270 patients diagnosed with PHI during the study period, 229 were enrolled (median follow-up 168 (IQR 96-232) weeks). Median age: 39 (IQR 32-48) years; 94.8% males, 86.5% Italians, 83.4% MSM, 56.8% carrying HIV-1 subtype B. Of them, 92.6% started early treatment within a median of 4 (IQR 2-7) days after diagnosis; median time to sustained suppression was 20 (IQR 8-32) weeks. Twenty TC (median size 3, range 2-9 individuals), including 68 patients, were identified. A diagnosis prior to 2015 was the unique factor associated with inclusion in a TC. Added value of UDS was the identification of shared quasispecies components in transmission pairs within TC.

The dual-target approach in viral HIV-1 viremia testing: An added value to virological monitoring?

New methods of HIV-1 RNA quantification based on dual-target detection are increasingly used in HIV viral load monitoring, but clinical implications and impact of dual-target detection on HIV-1 infection management are not established. Aptima HIV-1 Quant Dx assay is a last generation HIV viral load method, that uses pol and LTR as simultaneous target, providing quantitative results based mainly on pol target, while LTR target is used to report the results when pol signal is absent. In our laboratory, about 6% of results of all HIV-1 viral load tests performed with this platform in one year period resulted from LTR signal. Interestingly, LTR-based viremia (sometimes exceeding 1,000 copies/mL) was observed in a small proportion (up to 1%) of patients under ART, considered for long time virologically suppressed on the basis of a single target (pol-based) assay. Male gender, >700 vs <200 CD4 cell/mL and dual therapy including NRTI plus either NNRTI, or PI/b or INSTI were independently associated with increased risk of LTR-based HIV-1 viral load detection by multivariable logistic regression. A significant linear correlation was observed between LTR-based HIV-1 RNA levels and PBMC-associated proviral DNA. Moreover, in a small group of patients with HIV-1 RNA levels >200 copies/mL, longitudinal assessments showed parallel kinetics between plasma viremia and proviral DNA. Sequencing of pol region for drug resistance assessment in patients with LTR-based viremia failed on plasma HIV-1 RNA, while it was successful on proviral DNA. The detection/quantification of HIV-1 viremia based only on LTR signal with a dual target assay in samples resulting undetectable with the more conventional target pol needs accurate evaluation; unravelling the biological basis of this phenomenon, here described for the first time, is mandatory to establish relevance and implication by both pathogenetic (i.e. infectivity of LTR-detected viruses, reservoir turnover, immune activation, etc.) and clinical standpoint.

Correction: The dual-target approach in viral HIV-1 viremia testing: An added value to virological monitoring?

[This corrects the article DOI: 10.1371/journal.pone.0228192.].

Myeloid Derived Suppressor Cells Expansion Persists After Early ART and May Affect CD4 T Cell Recovery.

Myeloid-derived suppressor cells (MDSC) are expanded during HIV-1 infection and correlated with disease progression. MDSC expand in the early phase of primary infection depending on TRAIL level. In this study we evaluated the effect of ART on the frequency of MDSC in patients with primary HIV infection (PHI), and their impact on CD4 T cell reconstitution. MDSC frequency was evaluated by flow-cytometry in 60 PHI patients at 12, 24 and 48 weeks after ART initiation. Cytokine plasma levels were evaluated by Luminex technology at the same time points. The capacity of MDSC to modulate hematopoietic early progenitor cells' expansion was evaluated using the OP9/Dl1 in vitro system. As previously described, polymorphonuclear-MDSC (PMN-MDSC) frequency was higher in PHI compared to healthy donors. Interestingly, 48 weeks of successful ART failed to normalize the PMN-MDSC frequency. Moreover, PMN-MDSC frequency was not correlated with residual viral load, suggesting that the persistence of PMN-MDSC was not due to residual viral replication. Interestingly, patients with low PMN-MDSC frequency (<6%) at T0 had a higher HIV DNA at the same time point than individuals with high PMN-MDSC frequency (>6%). We also found an inverse correlation between PMN-MDSC frequency and CD4-T cell count at 48 weeks post-ART, which was confirmed by multivariate analysis adjusting for age and CD4 T cell number at baseline. These data suggest that the persistence of PMN-MDSC may impact CD4 T cell recovery. Indeed, in vitro PMN-MDSC impaired the expansion of CD34+CD38- hematopoietic early progenitors. Further, a balance between TRAIL and GM-CSF may be necessary to maintain a low MDSC level. In conclusion, early ART initiation was not able to normalize PMN-MDSC frequency that might impact the CD4 T cell recovery. These data open new questions regarding the clinical impact of MDSC persistence in HIV+ patients, in particular on non-AIDS related diseases.

Collaborative national multicenter for the identification of conversion factors from copies/mL to international units/mL for the normalization of HCMV DNA load.

The present multicentric (n = 11 laboratories) study aimed to identify conversion factors from copies/mL to international units (IU)/mL for the normalization of HCMV DNA load using the first WHO International Standard for HCMV nucleic acid amplification techniques and to enhance interlaboratory agreement of HCMV DNA quantification methods. Study protocols for whole blood and plasma (extraction and amplification) were performed to calculate conversion factors from HCMV DNA copy number to IU. The greatest variability was observed in samples with lower HCMV concentrations (3.0 Log10) in both biological matrices. Overall, 73.1% (206/282) of whole blood and 82.2% (324/394) of plasma samples analyzed fell within an acceptable variation range (±0.5 Log10 difference). An average of 0.64 (range 0.21-1.17) was the conversion factor calculated for the HCMV whole blood panel and 0.82 (range 0.39-2.2) for the HCMV plasma panel.

Toxoplasmosis in Transplant Recipients, Europe, 2010-2014.

Transplantation activity is increasing, leading to a growing number of patients at risk for toxoplasmosis. We reviewed toxoplasmosis prevention practices, prevalence, and outcomes for hematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT; heart, kidney, or liver) patients in Europe. We collected electronic data on the transplant population and prevention guidelines/regulations and clinical data on toxoplasmosis cases diagnosed during 2010-2014. Serologic pretransplant screening of allo-hematopoietic stem cell donors was performed in 80% of countries, screening of organ donors in 100%. SOT recipients were systematically screened in 6 countries. Targeted anti-Toxoplasma chemoprophylaxis was heterogeneous. A total of 87 toxoplasmosis cases were recorded (58 allo-HSCTs, 29 SOTs). The 6-month survival rate was lower among Toxoplasma-seropositive recipients and among allo-hematopoietic stem cell and liver recipients. Chemoprophylaxis improved outcomes for SOT recipients. Toxoplasmosis remains associated with high mortality rates among transplant recipients. Guidelines are urgently needed to standardize prophylactic regimens and optimize patient management.