IgG antibody levels against the SARS-CoV-2 spike protein in mother-child dyads after COVID-19 vaccination.

PURPOSE: We aimed to assess IgG antibodies against the SARS-CoV-2 spike protein (anti-SARS-CoV-2 S IgG) in vaccinated mothers and their infants at delivery and 2-3 months of age. METHODS: We conducted a prospective study on mothers who received at least one dose of the COVID-19 vaccine (Pfizer-BNT162b2, Moderna mRNA-1273, or Oxford-AstraZeneca ChAdOx1-S) during pregnancy and on their infants. The baseline was at the time of delivery (n = 93), and the end of follow-up was 2 to 3 months post-partum (n = 53). Serum anti-SARS-CoV-2 S IgG titers and ACE2 binding inhibition levels were quantified by immunoassays. RESULTS: Mothers and infants had high anti-SARS-CoV-2 S IgG titers against the B.1 lineage at birth. However, while antibody titers were maintained at 2-3 months post-partum in mothers, they decreased significantly in infants (p < 0.001). Positive and significant correlations were found between anti-SARS-CoV-2 S IgG titers and ACE2-binding inhibition levels in mothers and infants at birth and 2-3 months post-partum (r > 0.8, p < 0.001). Anti-S antibodies were also quantified for the Omicron variant at 2-3 months post-partum. The antibody titers against Omicron were significantly lower in mothers and infants than those against B.1 (p < 0.001). Again, a positive correlation was observed for Omicron between IgG titers and ACE2-binding inhibition both in mothers (r = 0.818, p < 0.001) and infants (r = 0.386, p < 0.005). Previous SARS-CoV-2 infection and COVID-19 vaccination near delivery positively impacted anti-SARS-CoV-2 S IgG levels. CONCLUSIONS: COVID-19 mRNA vaccines induce high anti-SARS-CoV-2 S titers in pregnant women, which can inhibit the binding of ACE2 to protein S and are efficiently transferred to the fetus. However, there was a rapid decrease in antibody levels at 2 to 3 months post-partum, particularly in infants.

Antibody levels to SARS-CoV-2 spike protein in mothers and children from delivery to six months later.

INTRODUCTION: Pregnant women are vulnerable to severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection. Neutralizing antibodies against the SARS-CoV-2 spike (S) protein protect from severe disease. This study analyzes the antibody titers to SARS-CoV-2 S protein in pregnant women and their newborns at delivery, and six months later. METHODS: We conducted a prospective study on pregnant women with confirmed SARS-CoV-2 infection and newborns. Antibody (IgG, IgM, and IgA) titers were determined using immunoassays in serum and milk samples. An angiotensin-converting enzyme 2 (ACE2) receptor-binding inhibition assay to the S protein was performed on the same serum and milk samples. RESULTS: At birth, antibodies to SARS-CoV-2 spike protein were detected in 81.9% of mothers' sera, 78.9% of cord blood samples, and 63.2% of milk samples. Symptomatic women had higher antibody titers (IgG, IgM, and IgA) than the asymptomatic ones (P < 0.05). At six months postpartum, IgG levels decreased drastically in children's serum (P < 0.001) but remained high in mothers' serum. Antibody titers correlated positively with its capacity to inhibit the ACE2-spike protein interaction at baseline in maternal sera (R2  = 0.203; P < 0.001), cord sera (R2  = 0.378; P < 0.001), and milk (R2  = 0.564; P < 0.001), and at six months in maternal sera (R2  = 0.600; P < 0.001). CONCLUSIONS: High antibody levels against SARS-CoV-2 spike protein were found in most pregnant women. Due to the efficient transfer of IgG to cord blood and high IgA titers in breast milk, neonates may be passively immunized to SARS-CoV-2 infection. Our findings could guide newborn management and maternal vaccination policies.

Immunoescape of HIV-1 in Env-EL9 CD8 + T cell response restricted by HLA-B*14:02 in a Non progressor who lost twenty-seven years of HIV-1 control.

BACKGROUND: Long-Term Non-Progressors (LTNPs) are untreated Human Immunodeficiency virus type 1 (HIV-1) infected individuals able to control disease progression for prolonged periods. However, the LTNPs status is temporary, as viral load increases followed by decreases in CD4 + T-cell counts. Control of HIV-1 infection in LTNPs viremic controllers, have been associated with effective immunodominant HIV-1 Gag-CD8 + T-cell responses restricted by protective HLA-B alleles. Individuals carrying HLA-B*14:02 control HIV-1 infection is related to an immunodominant Env-CD8 + T-cell response. Limited data are available on the contribution of HLA-B*14:02 CD8 + T -cells in LTNPs. RESULTS: In this study, we performed a virological and immunological detailed analysis of an HLA-B*14:02 LNTP individual that lost viral control (LVC) 27 years after HIV-1 diagnosis. We analysed viral evolution and immune escape in HLA-B*14:02 restricted CD8 + T -cell epitopes and identified viral evolution at the Env-EL9 epitope selecting the L592R mutation. By IFN-γ ELISpot and immune phenotype, we characterized HLA- B*14:02 HIV-1 CD8 + T cell responses targeting, Gag-DA9 and Env-EL9 epitopes before and after LVC. We observed an immunodominant response against the Env-EL9 epitope and a decreased of the CD8 T + cell response over time with LVC. Loss of Env-EL9 responses was concomitant with selecting K588R + L592R mutations at Env-EL9. Finally, we evaluated the impact of Env-EL9 escape mutations on HIV-1 infectivity and Env protein structure. The K588R + L592R escape variant was directly related to HIV-1 increase replicative capacity and stability of Env at the LVC. CONCLUSIONS: These findings support the contribution of immunodominant Env-EL9 CD8 + T-cell responses and the imposition of immune escape variants with higher replicative capacity associated with LVC in this LNTP. These data highlight the importance of Env-EL9 specific-CD8 + T-cell responses restricted by the HLA-B*14:02 and brings new insights into understanding long-term HIV-1 control mediated by Env mediated CD8 + T-cell responses.

Early antiretroviral therapy initiation effect on metabolic profile in vertically HIV-1-infected children.

BACKGROUND: Early combined antiretroviral treatment (cART) in perinatally acquired HIV-1 children has been associated with a rapid viral suppression, small HIV-1 reservoir size and reduced mortality and morbidity. Immunometabolism has emerged as an important field in HIV-1 infection offering both relevant knowledge regarding immunopathogenesis and potential targets for therapies against HIV-1. OBJECTIVES: To characterize the proteomic, lipidomic and metabolomic profile of HIV-1-infected children depending on their age at cART initiation. PATIENTS AND METHODS: Plasma samples from perinatally HIV-1-infected children under suppressive cART who initiated an early cART (first 12 weeks after birth, EARLY, n = 10) and late cART (12-50 weeks after birth, LATE, n = 10) were analysed. Comparative plasma proteomics, lipidomics and metabolomics analyses were performed by nanoLC-Orbitrap, UHPLC-qTOF and GC-qTOF, respectively. RESULTS: Seven of the 188 proteins identified exhibited differences comparing EARLY and LATE groups of HIV-1-infected children. Despite no differences in the lipidomic (n = 115) and metabolomic (n = 81) profiles, strong correlations were found between proteins and lipid levels as well as metabolites, including glucidic components and amino acids, with clinical parameters. The ratio among different proteins showed high discriminatory power of EARLY and LATE groups. CONCLUSIONS: Protein signature show a different proinflammatory state associated with a late cART introduction. Its associations with lipid levels and the relationships found between metabolites and clinical parameters may potentially trigger premature non-AIDS events in this HIV-1 population, including atherosclerotic diseases and metabolic disorders. Antiretroviral treatment should be started as soon as possible in perinatally acquired HIV-1-infected children to prevent them from future long-life complications.

Modulation of Monocyte Activation and Function during Direct Antiviral Agent Treatment in Patients Coinfected with HIV and Hepatitis C Virus.

The activation phenotypes and functional changes in monocyte subsets during hepatitis C virus (HCV) elimination in HIV/HCV-coinfected patients were evaluated. Twenty-two HIV/HCV-coinfected patients on suppressive combination antiretroviral treatment (cART) achieving HCV elimination after direct-acting antiviral (DAA) therapy and 10 HIV-monoinfected patients were included. The activation phenotype (10 markers) and polyfunctionality (intracellular interleukin-1α [IL-1α], IL-1ß, IL-6, IL-8, tumor necrosis factor alpha [TNF-α], and IL-10 production) in three monocyte subsets (classical, intermediate, and nonclassical) were evaluated by flow cytometry before and at the end of treatment. Cell-associated HIV DNA levels were assayed by droplet digital PCR. After HCV clearance, there was a significant increase in classical monocyte and decreases in intermediate and nonclassical monocyte levels. The levels of the activation markers CD49d, CD40, and CX3CR1 were decreased after treatment in the monocyte subsets, reaching the levels in HIV-monoinfected patients. After lipopolysaccharide (LPS) stimulation, although polyfunctionality significantly decreased in intermediate and nonclassical monocytes, some combinations, such as the IL-1α- (IL-1α-negative) IL-1ß- IL-6+ (IL-6-producing) IL-8- TNF-α- IL-10- combination, were remarkably increased at the end of treatment compared to the control group. Cell-associated HIV DNA levels correlated with activation markers before but not after treatment. HCV clearance after DAA treatment in patients on cART exerts an anti-inflammatory profile on monocyte subsets, activation phenotypes, and polyfunctionality. However, there is not a complete normalization compared with HIV-monoinfected patients.

Proteomic Profile Associated With Loss of Spontaneous Human Immunodeficiency Virus Type 1 Elite Control.

BACKGROUND: Elite controllers (ECs) spontaneously control plasma human immunodeficiency virus type 1 (HIV-1) RNA without antiretroviral therapy. However, 25% lose virological control over time. The aim of this work was to study the proteomic profile that preceded this loss of virological control to identify potential biomarkers. METHODS: Plasma samples from ECs who spontaneously lost virological control (transient controllers [TCs]), at 2 years and 1 year before the loss of control, were compared with a control group of ECs who persistently maintained virological control during the same follow-up period (persistent controllers [PCs]). Comparative plasma shotgun proteomics was performed with tandem mass tag (TMT) isobaric tag labeling and nanoflow liquid chromatography coupled to Orbitrap mass spectrometry. RESULTS: Eighteen proteins exhibited differences comparing PC and preloss TC timepoints. These proteins were involved in proinflammatory mechanisms, and some of them play a role in HIV-1 replication and pathogenesis and interact with structural viral proteins. Coagulation factor XI, α-1-antichymotrypsin, ficolin-2, 14-3-3 protein, and galectin-3-binding protein were considered potential biomarkers. CONCLUSIONS: The proteomic signature associated with the spontaneous loss of virological control was characterized by higher levels of inflammation, transendothelial migration, and coagulation. Galectin-3 binding protein could be considered as potential biomarker for the prediction of virological progression and as therapeutic target in ECs.

Factors Leading to the Loss of Natural Elite Control of HIV-1 Infection.

HIV-1 elite controllers (EC) maintain undetectable viral loads (VL) in the absence of antiretroviral treatment. However, these subjects have heterogeneous clinical outcomes, including a proportion that loses HIV-1 control over time. In this work, we compared, in a longitudinal design, transient EC, analyzed before and after the loss of virological control, with persistent EC. The aim was to identify factors leading to the loss of natural virological control of HIV-1 infection with a longitudinal retrospective study design. Gag-specific T-cell responses were assessed by in vitro intracellular polycytokine production quantified by flow cytometry. Viral diversity determinations and sequence dating were performed in proviral DNA by PCR amplification at limiting dilution of env and gag genes. The expression profile of 70 serum cytokines and chemokines was assessed by multiplex immunoassays. We identified transient EC as subjects with low Gag-specific T-cell polyfunctionality, high viral diversity, and high proinflammatory cytokine levels before the loss of control. Gag-specific T-cell polyfunctionality was inversely associated with viral diversity in transient controllers before the loss of control (r = -0.8; P = 0.02). RANTES was a potential biomarker of transient control. This study identified virological and immunological factors, including inflammatory biomarkers associated with two different phenotypes within EC. These results may allow a more accurate definition of EC, which could help in better clinical management of these individuals and in the development of future curative approaches.IMPORTANCE There is a rare group of HIV-infected patients who have the extraordinary capacity to maintain undetectable viral load levels in the absence of antiretroviral treatment, the so-called HIV-1 elite controllers (EC). However, there is a proportion within these subjects that eventually loses this capability. In this work, we found differences in virological and immune factors, including soluble inflammatory biomarkers, between subjects with persistent control of viral replication and EC that will lose virological control. The identification of these factors could be a key point for a right medical care of those EC who are going to lose natural control of viral replication and for the design of future immunotherapeutic strategies using as a model the natural persistent control of HIV infection.

Association between a Suppressive Combined Antiretroviral Therapy Containing Maraviroc and the Hepatitis B Virus Vaccine Response.

The response to the HBV vaccine in HIV-infected patients is deficient. Our aim was to analyze whether a suppressive combined antiretroviral treatment (cART) containing maraviroc (MVC-cART) was associated with a better response to HBV vaccine. Fifty-seven patients on suppressor cART were administered the HBV vaccine. The final response, the early response, and the maintenance of the response were assessed. An anti-HBs titer of >10 mIU/ml was considered a positive response. A subgroup of subjects was simultaneously vaccinated against hepatitis A virus (HAV). Lineal regression analyses were performed to determine demographic, clinical, and immunological factors associated with the anti-HBs titer. Vaccine response was achieved in 90% of the subjects. After 1 year, 81% maintained protective titers. Only simultaneous HAV vaccination was independently associated with the magnitude of the response in anti-HBs titers, with a P value of 0.045 and a regression coefficient (B) [95% confident interval (CI)] of 236 [5 to 468]. In subjects ≤50 years old (n = 42), MVC-cART was independently associated with the magnitude of the response (P = 0.009; B [95% CI], 297 [79 to 516]) together with previous vaccination and simultaneous HAV vaccination. High rates of HBV vaccine response can be achieved by revaccination, simultaneous HAV vaccination, and administration of cARTs including MVC. MVC may be considered for future vaccination protocols in patients on suppressive cART.

Improved CD4 T cell profile in HIV-infected subjects on maraviroc-containing therapy is associated with better responsiveness to HBV vaccination.

BACKGROUND: Maraviroc-containing combined antiretroviral therapy (MVC-cART) improved the response to the hepatitis B virus (HBV) vaccine in HIV-infected subjects younger than 50 years old. We aimed here to explore the effect of this antiretroviral therapy on different immunological parameters that could account for this effect. METHODS: We analysed baseline samples of vaccinated subjects under 50 years old (n = 41). We characterized the maturational subsets and the expression of activation, senescence and prone-to-apoptosis markers on CD4 T-cells; we also quantified T-regulatory cells (Treg) and dendritic cell (DC) subsets. We used binary logistic regression to evaluate the immunological impact of MVC-cART, correlation with MVC exposure and linear regression for association with the magnitude of the HBV vaccine response. RESULTS: HIV-infected subjects on MVC-cART prior to vaccination showed increased recent thymic emigrants levels and reduced myeloid-DC levels. A longer exposure to MVC-cART was associated with lower frequencies of Tregs and activated and proliferating CD4 T-cells. Furthermore, the frequencies of activated and proliferating CD4 T-cells were inversely associated with the magnitude of the HBV vaccine response. CONCLUSION: The beneficial effect of MVC-cART in the HBV vaccine response in subjects below 50 years old could be partially mediated by its reducing effect on the frequencies of activated and proliferating CD4 T-cells prior to vaccination.

Coordinate-based co-localization-mediated analysis of arrestin clustering upon stimulation of the C-C chemokine receptor 5 with RANTES/CCL5 analogues.

G protein-coupled receptor activation and desensitization leads to recruitment of arrestin proteins from cytosolic pools to the cell membrane where they form clusters difficult to characterize due to their small size and further mediate receptor internalization. We quantitatively investigated clustering of arrestin 3 induced by potent anti-HIV analogues of the chemokine RANTES after stimulation of the C-C chemokine receptor 5 using single-molecule localization-based super-resolution microscopy. We determined arrestin 3 cluster sizes and relative fractions of arrestin 3 molecules in each cluster through image-based analysis of the localization data by adapting a method originally developed for co-localization analysis from molecular coordinates. We found that only classical agonists in the set of tested ligands were able to efficiently recruit arrestin 3 to clusters mostly larger than 150 nm in size and compare our results with existing data on arrestin 2 clustering induced by the same chemokine analogues.

Absolute and functional iron deficiency: Biomarkers, impact on immune system, and therapy.

Iron is essential for numerous physiological processes and its deficiency often leads to anemia. Iron deficiency (ID) is a global problem, primarily affecting reproductive-age women and children, especially in developing countries. Diagnosis uses classical biomarkers like ferritin or transferrin saturation. Recent advancements include using soluble transferrin receptor (sTfR) or hepcidin for improved detection and classification of absolute and functional iron deficiencies, though mostly used in research. ID without anemia may present symptoms like asthenia and fatigue, even without relevant clinical consequences. ID impacts not only red-blood cells but also immune system cells, highlighting its importance in global health and immune-related comorbidities. Managing ID, requires addressing its cause and selecting appropriate iron supplementation. Various improved oral and intravenous products are available, but further research is needed to refine treatment strategies. This review updates on absolute and functional iron deficiencies, their relationships with the immune system and advancements in diagnosis and therapies.

Torque teno virus: a potential marker of immune reconstitution in youths with vertically acquired HIV.

Torque teno virus (TTV) viral load (VL), a component of the human virome, increases during immune suppression or dysregulation. This study aimed to explore TTV VL in youths living with vertically acquired HIV (YWVH) and its potential as an immunovirological marker. We performed an observational, retrospective study involving YWVH under antiretroviral treatment (ART) from the Spanish Cohort of HIV-infected children, adolescents, and vertically HIV-infected patients transferred to Adult Units (CoRISpe-FARO), compared to HIV-negative healthy donors (HD). Plasma TTV VL was assessed by qPCR. T-cell phenotype was analysed on cryopreserved peripheral blood mononuclear cells by flow cytometry. Correlations with baseline CD4 and CD8 and long-term virological evolution were examined. A total of 57 YWVH were compared with 23 HD. YWVH had a median CD4 T-cells of 736 cells/mm3 [IQR: 574-906], a median of 17 years [IQR: 14-20.5] since ART initiation, and 65 months [IQR: 39-116] under HIV-RNA virological control. TTV VL was higher among YWVH and in males compared with females (p < 0.05). Among YWVH, TTV VL correlated with CD4 and CD8 counts and the CD4/CD8 ratio (p = 0.002; r = - 0.39, p = 0.037; r = 0.277, p = 0.005; r = - 0.37 respectively). TTV VL correlated with activation expression markers (HLA-DR+/CD38+) on CD4 (p = 0.007, r = 0.39) and the soluble proinflammatory cytokine IL-6 (p = 0.006, r = 0.38).

Quantitative morphological analysis of arrestin2 clustering upon G protein-coupled receptor stimulation by super-resolution microscopy.

Clustering of arrestins upon G protein-coupled receptor stimulation is a phenomenon that is well-known but difficult to describe quantitatively due to the size of the clusters close to the diffraction limit of visible light. We introduce a general method to quantitatively investigate the clustering of arrestin following stimulation of the C-C chemokine receptor 5 (CCR5) using single-molecule super-resolution imaging and coordinate and image-based cluster analysis. We investigated the effect of potent anti-HIV ligands of CCR5 with different pharmacological profiles on arrestin2 cluster formation and found that only the ligands capable of inducing CCR5 internalization induced arrestin2 recruitment and clustering. We further demonstrate that the fraction of arrestin2 molecules found in clusters larger than 100nm correlates with the magnitude of ligand-induced CCR5 internalization, but not with G protein activation, indicating that recruitment of arrestin2 to CCR5 is independent of G protein activation. Pre-treatment of the cells with the drug cytochalasin D, which blocks actin polymerization, led to the formation of larger clusters, whereas the inhibitor of microtubule polymerization nocodazole had little effect on arrestin2 recruitment, suggesting an active role of actin in the organization and dynamics of these aggregates.

Real-world experience of intravenous iron sucrose supplementation and dynamics of soluble transferrin receptor and hepcidin in a Spanish cohort of absolute iron deficient patients.

The study evaluated the safety and effectiveness of the generic intravenous (IV) iron treatment (Feriv®), in a Spanish cohort with absolute iron deficiency (ID) (serum ferritin <50 ng/ml, with or without anaemia) (n = 122; 91% women; median age of 44 years [IQR: 33.7-54]). Iron-related biomarkers were measured before treatment (baseline), 2 weeks after beginning the protocol (intermediate control, IC) and between 7 and 10 days after treatment completion (final time-point). Primary efficacy endpoints were ferritin levels ≥ 50 ng/ml, anaemia restoration or an increase in haemoglobin (Hb) of at least one point in patients without baseline anaemia. After treatment, iron-related biomarkers improved, including ferritin, Hb, sideremia, transferrin, transferrin saturation index, soluble transferrin receptor (sTfR), and hepcidin. Baseline ferritin concentration (13.5 ng/ml [IQR: 8-24.2]) increased at the IC and continued rising at the final time-point, reaching a median ferritin of 222 ng/ml and 97.3% of patients ≥ 50 ng/ml. At the final time-point, anaemia prevalence decreased from 26.2% to 5%, while the 34.1% without baseline anaemia showed an increase in Hb of at least one point. Headache was the only drug-adverse event recorded in 2.3% of patients. At a late time-point (27.5 median weeks after ending therapy [IQR: 22-40]), evaluated in a subgroup of 66 patients, 18% had ferritin levels < 50 ng/ml. Multivariate analysis showed that low baseline ferritin and high sTfR/hepcidin ratio tended to be independently associated with ID recurrence. Feriv® is a safe, effective first-line treatment for absolute ID, with improvement of serum ferritin and Hb. ID recurrence was associated with the baseline degree of iron stores depletion, indicated by serum ferritin, and sTfR/hepcidin ratio.

Caecum OX40+CD4 T-cell subset associates with mucosal damage and key markers of disease in treated HIV-infection.

BACKGROUND: Blood OX40-expressing CD4 T-cells from antiretroviral (ART)-treated people living with HIV (PWH) were found to be enriched for clonally-expanded HIV sequences, hence contributing to the HIV reservoir. OX40-OX40L is also a checkpoint regulator of inflammation in multiple diseases. We explored gut mucosal OX40+CD4+ T-cells and their potential significance in HIV disease. METHODS: Biopsies of caecum and terminal-ileum of ART-treated PWH (n = 32) were obtained and mucosal damage and HIV reservoir were assessed. Mucosal OX40+ and Ki67+ CD4 T-cell subsets, as well as several tissue T-cell subsets modulating mucosal integrity and homeostasis (Th17, Th22, Treg, Tc17, Tc22, IL17+TCRγδ, IL22+TCRγδ) were quantified. Inflammatory-related markers, T-cell activation and thymic output were also determined in blood samples. Correlations were explored using Spearman rank test and corrected for multiple comparisons by Benjamini-Hochberg. RESULTS: Compared to healthy controls, a high frequency of mucosal, mainly caecum, CD4 T-cells were OX40+ in PWH. Such frequency strongly correlated with nadir CD4 (r = -0.836; p < 0.0001), CD4/CD8 ratio (r = -0.630; p = 0.002), caecum mucosal damage (r = 0.606; p = 0.008), caecum Th22 (r = -0.635; p = 0.002), caecum Th17 (r = 0.474; p = 0.03) and thymic output (r = -0.686; p < 0.001). It also correlated with Neutrophil-to-Lymphocyte Ratio and blood CD4 T-cell activation and tended to with mucosal HIV reservoir. CONCLUSION: High frequencies of caecum OX40+CD4 T-cells are found in people with HIV (PWH) and successful viral control. Interestingly, this cellular subset reflects key markers of disease and peripheral T-cell activation, as well as HIV-driven mucosal damage. OX40+CD4 T-cells deserve further investigation since they could expand because of T-cell homeostatic proliferation and relate to the Th22/Th17 gut mucosal ratio.

Persistent Exhausted T-Cell Immunity after Severe COVID-19: 6-Month Evaluation in a Prospective Observational Study.

INTRODUCTION: Severe COVID-19 can result in a significant and irreversible impact on long-term recovery and subsequent immune protection. Understanding the complex immune reactions may be useful for establishing clinically relevant monitoring. METHODS: Hospitalized adults with SARS-CoV-2 between March/October 2020 (n = 64) were selected. Cryopreserved peripheral blood mononuclear cells (PBMCs) and plasma samples were obtained at hospitalization (baseline) and 6 months after recovery. Immunological components' phenotyping and SARS-CoV-2-specific T-cell response were studied in PBMCs by flow cytometry. Up to 25 plasma pro/anti-inflammatory cytokines/chemokines were assessed by LEGENDplex immunoassays. The SARS-CoV-2 group was compared to matched healthy donors. RESULTS: Biochemical altered parameters during infection were normalized at a follow-up time point in the SARS-CoV-2 group. Most of the cytokine/chemokine levels were increased at baseline in the SARS-CoV-2 group. This group showed increased Natural Killer cells (NK) activation and decreased CD16high NK subset, which normalized six months later. They also presented a higher intermediate and patrolling monocyte proportion at baseline. T cells showed an increased terminally differentiated (TemRA) and effector memory (EM) subsets distribution in the SARS-CoV-2 group at baseline and continued to increase six months later. Interestingly, T-cell activation (CD38) in this group decreased at the follow-up time point, contrary to exhaustion markers (TIM3/PD1). In addition, we observed the highest SARS-CoV-2-specific T-cell magnitude response in TemRA CD4 T-cell and EM CD8 T-cell subsets at the six-months time point. CONCLUSIONS: The immunological activation in the SARS-CoV-2 group during hospitalization is reversed at the follow-up time point. However, the marked exhaustion pattern remains over time. This dysregulation could constitute a risk factor for reinfection and the development of other pathologies. Additionally, high SARS-CoV-2-specific T-cells response levels appear to be associated with infection severity.

Transient Viral Rebound in Children with Perinatally Acquired HIV-1 Induces a Unique Soluble Immunometabolic Signature Associated with Decreased CD4/CD8 Ratio.

BACKGROUND: To determine by multi-omic analysis changes in metabolites, lipids, and proteins as a consequence of transient viral rebound (tVR) in children with perinatally acquired HIV-1 (PHIV). METHODS: Plasma samples from children with PHIV and with tVR (first episode of transient RNA-HIV viral load >20 copies/ml followed by suppression) on the time-point immediately before (pre-tVR) and after (post-tVR) the tVR were assessed. Multi-omic analyses were performed using nLC-Orbitrap, GC-qTOF-MS, and LC-qTOF-MS. RESULTS: Comparing pre- and post-tVR time-points, HIV-1 children with tVR (n = 5) showed a trend to a decrease in ratio CD4/CD8 (p = 0.08) but no significant differences were observed in plasma metabolites, lipids, or proteins. Post-tVR condition was compared with a reference group of children with PHIV with persistent viral control (n = 9), paired by sex, age, and time under antiretroviral treatment. A total of 10 proteins, 8 metabolites, and 2 lipids showed significant differences (p < 0.05): serotransferrin, clusterin, kininogen-1, succinic acid, threonine, 2-hydroxyisovaleric acid, methionine, 2-hydroxyglutaric, triacylglyceride 50:0 (TG50:0), and diacylglyceride 34:1 (DG34:1) were upregulated while alpha-2-macroglobulin, apolipoprotein A-II, carboxylic ester hydrolase, apolipoprotein D, coagulation factor IX, peptidase inhibitor 16, SAA2-SAA4 readthrough, oleic acid, palmitoleic acid, and D-sucrose downregulated on post-tVR time-point compared to the reference group. Ratio CD4/CD8 correlated with apolipoprotein A-II, DG34:1, and methionine (p = 0.004; ρ = 0.71, p = 0.016; ρ = -0.63; and p = 0.032; ρ = -0.57, respectively). Nadir CD4+ correlated inversely with kininogen-1 (p = 0.022; ρ = -0.60) and positively with D-sucrose (p = 0.001; ρ = 0.77). CONCLUSIONS: tVR followed by suppression implies changes in soluble proteins, lipids, and metabolites that correlate with immunological parameters, mainly ratio CD4/CD8, that decreased after tVR. These distinct soluble biomarkers could be considered potential biomarkers of immune progression.

Long-term evolution in liver disease markers and immune and lipid profiles in vertically HIV/HCV-coinfected youths with sustained viral response after direct-acting antivirals therapy.

This study aimed to analyse the long-term effect of direct-acting antivirals (DAAs) in vertically acquired HIV/HCV-coinfected youths. We performed a multicentre, longitudinal and observational study within the Spanish Cohort of HIV-infected children and adolescents and vertically HIV-infected patients transferred to Adult Units (CoRISpe-FARO). We included HIV/HCV-coinfected youths (n = 24) that received DAAs between 2015 and 2017 with successful sustained viral response (SVR) with a subsequent follow-up of at least three years. Long-term evolution in liver disease severity and haematologic markers, lipid and immune profiles after SVR were assessed. Study times were the start date of DAAs treatment (baseline, T0) and 1, 2, 3, 4 and 5 years after SVR (T1, T2, T3, T4 and T5, respectively). We observed global improvements in liver function data that persist over time and a favourable haematologic and immune outcome at the long-term including a constant augment in leucocytes, neutrophils, neutrophils to lymphocytes ratio (NLR) and CD4/CD8 ratio over-time. Regarding the lipid profile, we found a significant increase in total cholesterol T2, total cholesterol/high-density lipoprotein (HDL) ratio at T4, triglycerides at T5, low-density lipoprotein (LDL) over time, and a decrease in HDL in all patients but with marked higher levels in the subgroup receiving anti-HIV Protease Inhibitor (PI)-based regimens. Comparisons of vertically HIV/HCV-coinfected youths after SVR at 3-year follow-up and a control group of vertically HIV-monoinfected youths never infected by HCV showed no significant differences in most variables analysed, suggesting a possible normalization in all parameters.

Toll-like receptor agonists enhance HIV-specific T cell response mediated by plasmacytoid dendritic cells in diverse HIV-1 disease progression phenotypes.

BACKGROUND: Plasmacytoid dendritic cells (pDCs) sense viral and bacterial products through Toll-like receptor (TLR)-7 and -9 and translate this sensing into Interferon-α (IFN-α) production and T-cell activation. The understanding of the mechanisms involved in pDCs stimulation may contribute to HIV-cure immunotherapeutic strategies. The objective of the present study was to characterize the immunomodulatory effects of TLR agonist stimulations in several HIV-1 disease progression phenotypes and in non HIV-1 infected donors. METHODS: pDCs, CD4 and CD8 T-cells were isolated from 450 ml of whole blood from non HIV-1 infected donors, immune responders (IR), immune non responders (INR), viremic (VIR) and elite controller (EC) participants. pDCs were stimulated overnight with AT-2, CpG-A, CpG-C and GS-9620 or no stimuli. After that, pDCs were co-cultured with autologous CD4 or CD8 T-cells and with/without HIV-1 (Gag peptide pool) or SEB (Staphylococcal Enterotoxin B). Cytokine array, gene expression and deep immunophenotyping were assayed. FINDINGS: pDCs showed an increase of activation markers levels, interferon related genes, HIV-1 restriction factors and cytokines levels after TLR stimulation in the different HIV-disease progression phenotypes. This pDC activation was prominent with CpG-C and GS-9620 and induced an increase of HIV-specific T-cell response even in VIR and INR comparable with EC. This HIV-1 specific T-cell response was associated with the upregulation of HIV-1 restriction factors and IFN-α production by pDC. INTERPRETATION: These results shed light on the mechanisms associated with TLR-specific pDCs stimulation associated with the induction of a T-cell mediated antiviral response which is essential for HIV-1 eradication strategies. FUNDING: This work was supported by Gilead fellowship program, the Instituto de Salud Carlos III (Fondo Europeo de Desarrollo Regional, FEDER, "a way to make Europe") and the Red Temática de Investigación Cooperativa en SIDA and by the Spanish National Research Council (CSIC).