Household transmission of SARS-CoV-2 infection in the Paris/Ile-de-France area.

This st udy aims to evaluate the prevalence of SARS-CoV-2 antibodies in locked-down family households to determine viral dynamics and immunity acquisition. COVID-19 individuals and their households in lockdown under the same roof during early spring 2020 were interviewed and tested using rapid immunochromatographic lateral flow antibodies assays (LFA) between July and September 2020. Outcomes were secondary infection rate (SIR) among contacts, household infection rate, and predictors of transmission. We enrolled 87 households including 87 COVID-19 index cases (female 78.2%; median age: 47.0 years, IQR: 42.0-51.5) and 255 contacts (males: 52.9%; median age: 19.0 years, IQR: 11.0-43.5) consisting of their children (42%) or spouses/partners (28.2%). A total of 95/255 contacts were SARS-CoV-2 antibody positive leading to a SIR of 37.3% (95% confidence interval (CI): 31.3-43.5%). Viral transmission was observed in 54 households (62%). SARS-CoV-2 infection was asymptomatic in 33/95 (34.7%) of SARS-CoV-2-positive contacts. Independent predictors of virus transmission from index to contacts were housing surface area < 60 m2 (OR: 5.6 [1.1; 28.2] and a four-member family compared to five (OR: 3.6 [1.2; 10.3]). Households represent a high-risk setting for SARS-CoV-2 transmission through close contact within the family amplified by the number of family members and the housing surface area.

Once-daily etravirine/raltegravir (400/800 mg q24h) dual therapy maintains viral suppression over 48 weeks in HIV-infected patients switching from a twice-daily etravirine/raltegravir (200/400 mg q12h) regimen.

BACKGROUND: Etravirine/raltegravir dual therapy has been shown to be highly effective as a twice-daily (q12h) regimen in suppressed HIV-infected patients enrolled in the ANRS-163 study. OBJECTIVES: As a once-daily (q24h) regimen is easier for daily life, we aimed to evaluate the capacity of etravirine/raltegravir (400/800 mg) q24h to maintain viral suppression in patients on etravirine/raltegravir q12h. METHODS: Patients on a suppressive etravirine/raltegravir q12h regimen for at least 96 weeks were switched to etravirine/raltegravir q24h in this prospective, multicentre, open-label, single-arm study. Primary outcome was the rate of virological failure (VF: confirmed pVL >50 copies/mL, single pVL >400 copies/mL or single pVL >50 copies/mL with ART change) at Week 48 (W48). Secondary outcomes included treatment strategy success rate (no VF and no treatment discontinuation), regimen tolerability, plasma drug concentrations and resistance profile in the case of VF. RESULTS: A total of 111 patients were enrolled, with a median (IQR) age of 57 years (52-62), CD4 count of 710 cells/mm3 (501-919) and viral suppression for 7.9 years (5.9-10.7). Two patients experienced viral rebound at W24 and W48, leading to a VF rate of 2.0% (95% CI 0.5-7.8) at W48, associated with INSTI resistance in one case. Both had past NNRTI mutations. Ten patients discontinued treatment for adverse events (n = 2), investigator or patient decisions (n = 3), lost to follow-up (n = 3), death (n = 1) or pregnancy (n = 1). Overall, the strategy success rate was 89% (95% CI 81.5-93.6) at W48. In a subgroup of 64 patients, median (IQR) plasma C24h concentrations were 401 ng/mL (280-603) for etravirine and 62 ng/mL (31-140) for raltegravir. CONCLUSIONS: Switching patients virally suppressed on etravirine/raltegravir q12h to the same regimen but given q24h was highly effective in maintaining virological suppression in HIV-infected patients.

HIV therapeutic vaccine enhances non-exhausted CD4+ T cells in a randomised phase 2 trial.

VAC-3S is a therapeutic vaccine comprising a highly conserved HIV-gp41 motif coupled with the CRM197 carrier protein. High levels of anti-3S antibodies (Abs) have been associated with improved protection of CD4+ T-cell survival. A previous phase 1 study demonstrated the safety of VAC-3S. This multicentre, randomised, double-blind, placebo-controlled phase 2 clinical trial enroled between January 2014 and March 2015 HIV-1-infected patients under ART with plasma HIV RNA levels below 50 copies/mL and CD4 counts between 200 and 500 cells/µL. Participants were immunised with 16, 32, or 64 µg of VAC-3S, and compared to placebo. The primary outcome was immunogenicity assessed by changes from baseline of anti-3S Abs levels at week 12. Secondary outcomes included adverse events and the course of plasma HIV RNA level, CD4 count, CD4/CD8 ratio, inflammation and immune checkpoints from week 0 to week 48. Vaccination was well tolerated with no serious adverse events and induced a significant increase in anti-3S Ab response in vaccinated patients (p < 0.0001), compared to placebo. In high responders, the robust increased of CD4 count was associated with a significant and sustained reduction of PD-1 expression on CD4+ T cells through week 48 (variance p = 0.0017). PD-1 expression was correlated with level of anti-3S Abs (p = 0.0092, r = -0.68) and expression of NKp44L (p < 0.0001; r = 0.54) in CD4+ T cells. Our findings regarding the increase of non-exhausted CD4+ T cells have potentially important application in personalised HIV vaccination for HIV-infected patients with high level of PD-1 to improve their T-cell immune function.

Treatment interruption in chronically HIV-infected patients with an ultralow HIV reservoir.

OBJECTIVES: To investigate the potential for combination antiretroviral therapy (cART)-free remission following analytic treatment interruption (ATI) in chronically HIV-infected patients with ultralow cell-associated DNA. METHODS: Pilot study of patients (pts) with plasma viral load (pVL) less than 50 copies/ml for more than 2 years on cART, CD4 above 500 cells/µl, CD4/CD8 above 0.9, CD4 nadir above 300 cells/µl and HIV-DNA below 100 copies/10 peripheral blood mononuclear cells (PBMCs), undergoing treatment interruption. Ultrasensitive pVL, CD4 cell count, triplicate HIV-DNA were measured at D0, W2, W4, and every 4 weeks off-ART until W48 and at W4, W12 and W24 after ART resumption (RxR). RxR occurred in case of pVL rebound above 400 copies/ml or CD4 above 400 cells or HIV-related clinical event. The primary endpoint was the percentage of patients who did not reach RxR criteria at W24. Individuals were to be enrolled in three cohorts of five. Enrolment in cohort 2 began if at least one of five patients from cohort 1 remained in success at W8. Cohort 3 did not start. RESULTS: Ten patients were enrolled, with median (range) CD4 1118 cells/µl (608-1494), CD4/CD8 2.1 (1.4-2.6), HIV-DNA 66 copies/10 PBMC (<66-66) at screening, viral suppression of 4.9 years (2.9-8.3), CD4 nadir 495 cells/µl (330-739). One patient remained off-ART up to W48. Viral rebound occurred in nine of 10 patients at W2 (2 patients), W4 (6 patients) and W12 (one patient). pVL was resuppressed on cART at W4 (8 patients) and W12 (one patient). HIV DNA returned to baseline values within a median of 12 weeks following RxR. CONCLUSION: In a highly selected population of 10 patients with chronic HIV infection, an excellent immune status, durable virological suppression and ultralow reservoir, the success rate of ATI was 10% (95% confidence interval 0.3-44.5%) and nine of 10 patients had prompt rebound of plasma viremia. Resumption of ART led to return to baseline cell-associated total DNA.

Vitamin D supplementation is associated with reduced immune activation levels in HIV-1-infected patients on suppressive antiretroviral therapy.

BACKGROUND: A majority of HIV-1-infected patients present a severe deficit in vitamin D, which predicts short-term mortality. Vitamin D is a naturally synthesized hormone, with important immunomodulatory functions. In the general population, its deficit has been associated with increased markers of inflammation. Vitamin D deficit may therefore play a role in the establishment of elevated systemic immune activation, which persists despite suppressive antiretroviral therapy (ART) in HIV-infected patients, and is predictive of disease progression; and vitamin D supplementation may be beneficial in this context. METHODS: We performed both a cross-sectional study (vitamin D deficit versus normal level) and a longitudinal study (upon vitamin D supplementation for 6 to 12 months) of HIV-1-infected patients receiving suppressive ART. The primary outcome measure was the percentage of activated memory CD8(+) T cells in blood, which is a robust marker associated with disease progression. Secondary outcomes included general T-lymphocyte and B-lymphocyte phenotype. RESULTS: Although vitamin D deficiency had no influence on T-cell and B-cell subset distribution, we found an association between vitamin D and immune activation levels in HIV-1-infected patients. Vitamin D supplementation in vitamin D-deficient patients resulted in reduced immune activation levels. CONCLUSION: The present data support the rationale of vitamin D supplementation in the routine clinical management of HIV-1-infected patients, in order to decrease immune activation levels and possibly improve long-term survival.

Neutrophils in antiretroviral therapy-controlled HIV demonstrate hyperactivation associated with a specific IL-17/IL-22 environment.

BACKGROUND: Despite control of HIV infection under antiretroviral therapy (ART), immune T-cell activation persists in patients with controlled HIV infection, who are at higher risk of inflammatory diseases than the general population. PMNs play a key role in host defenses against invading microorganisms but also potentiate inflammatory reactions in cases of excessive or misdirected responses. OBJECTIVE: The aim of our study was to analyze PMN functions in 60 ART-treated and controlled HIV-infected patients (viral load, <20 RNA copies/mL; CD4 count, ≥ 350 cells/mm(3)) with (HIV[I] group) and without (HIV[NI] group) diseases related to an inflammatory process and to compare them with 22 healthy control subjects. METHODS: Flow cytometry was used to evaluate PMN functions in whole-blood conditions. We studied in parallel the activation markers of T lymphocytes and monocytes and the proinflammatory cytokine environment. RESULTS: Blood samples from HIV-infected patients revealed basal PMN hyperactivation associated with deregulation of the apoptosis/necrosis equilibrium. Interestingly, this hyperactivation was greater in HIV(I) than HIV(NI) patients and contrasted with a lack of monocyte activation in both groups. The percentage of circulating cells producing IL-17 was also significantly higher in HIV-infected patients than in control subjects and was positively correlated with markers of basal PMN activation. In addition, the detection of IL-22 overproduction in HIV(NI) patients suggests that it might contribute to counteracting chronic inflammatory processes during HIV infection. CONCLUSIONS: This study thus demonstrates the presence of highly activated PMNs in HIV-infected patients receiving effective ART and the association of these cells with a specific IL-17/IL-22 environment.

Protective effect of IgM against colonization of the respiratory tract by nontypeable Haemophilus influenzae in patients with hypogammaglobulinemia.

BACKGROUND: Primary immunoglobulin deficiencies lead to recurrent bacterial infections of the respiratory tract and bronchiectasis, even with adequate immunoglobulin replacement therapy. It is not known whether patients able to secrete IgM (eg, those with hyper-IgM [HIgM] syndrome) are as susceptible to these infections as patients who lack IgM production (eg, those with panhypogammaglobulinemia [PHG]). OBJECTIVE: This study is aimed at identifying specific microbiological and clinical (infections) characteristics that distinguish immunoglobulin-substituted patients with PHG from patients with HIgM syndrome. METHODS: A cohort of patients with HIgM syndrome (n = 25) and a cohort of patients with PHG (n = 86) were monitored prospectively for 2 years while receiving similar polyvalent immunoglobulin replacement therapies. Regular bacterial analyses of nasal swabs and sputum were performed, and clinical events were recorded. In parallel, serum and saliva IgM antibody concentrations were measured. RESULTS: When compared with patients with PHG, patients with HIgM syndrome were found to have a significantly lower risk of nontypeable Haemophilus influenzae carriage in particular (relative risk, 0.39; 95% CI, 0.21-0.63). Moreover, patients with HIgM syndrome (including those unable to generate somatic hypermutations of immunoglobulin genes) displayed anti-nontypeable H influenzae IgM antibodies in their serum and saliva. Also, patients with HIgM syndrome had a lower incidence of acute respiratory tract infections. CONCLUSIONS: IgM antibodies appear to be microbiologically and clinically protective and might thus attenuate the infectious consequences of a lack of production of other immunoglobulin isotypes in patients with HIgM syndrome. Polyvalent IgG replacement therapy might not fully compensate for IgM deficiency. It might thus be worth adapting long-term antimicrobial prophylactic regimens according to the underlying B-cell immunodeficiency phenotype.

A natural CCL5/RANTES variant antagonist for CCR1 and CCR3.

The N-terminal domain of the chemokine CCL5/regulated upon activation normal T cell expressed and secreted (RANTES) has been shown to be critical for its biological activity on leukocytes. Several N-terminus-modified CCL5/RANTES derivatives, such as N-Terminal truncated CCL5/RANTES, Met-RANTES, and amino-oxypentane (AOP)-RANTES exhibited antagonist or partial agonist functions when investigated on the properties of their receptors CCR1, CCR3, and CCR5. Studying 95 African samples from Cameroon, we found a naturally occurring variant of CCL5/RANTES containing a missense mutation located in the first amino acid of the secreted form (S24F). S24F binds CCR1, CCR3, and CCR5 and triggers receptor down-modulation comparable to CCL5/RANTES. Moreover, in CCR5 positive cells, S24F elicits cellular calcium mobilization equivalent to that obtained with CCL5/RANTES. By contrast, S24F does not provoke any response in CCR1 and CCR3 positive cells. As CCL5/RANTES is able to attract different subtypes of leukocytes into inflamed tissue and intervenes in a wide range of allergic and autoimmune diseases, the discovery of this natural N-terminus-modified CCL5/RANTES analogue exhibiting differential effects on CCL5/RANTES receptors, opens up additional perspectives for therapeutic intervention.

Influence of the R22H variant of macrophage inflammatory protein 1beta/Lag-1 in HIV-1 survival.

The chemokine macrophage inflammatory protein 1beta/CCL4, ligand of the major HIV co-receptor CCR5, is encoded by two genes, Act-2 and Lag-1. Our work focused on R22H, a variant of Lag-1 located near the N-loop, in the 310 turn, a domain essential for interacting with CCR5. We observed that HIV-1-infected patients from the SEROCO cohort, bearing the R22H variant either at the homozygous or heterozygous state, exhibit a worse global survival compared with wild-type homozygous individuals.

Biochemical and HIV-1 coreceptor properties of K26R, a new CCR5 Variant in China's Sichuan population.

Despite multiple exposures to HIV-1, some individuals remain uninfected. This resistance to HIV infection has been associated with homozygosity for a 32-basepair deletion in the CCR5 receptor gene. This variant is frequent in caucasians but extremely rare in Asians and Africans. Identifying variations in the CCR5 gene that affect susceptibility to HIV infection in non-caucasians is therefore of great interest. In this report, we identify 5 CCR5 coding region variants in a Chinese population. The K26R mutation is an undescribed gene variant, whereas 228delK was already found in caucasians and G106R, C178R, and R223Q were previously described in Asian populations and functionally analyzed. As the function of K26R was still unknown, we focused our work on studying its chemokine receptor activity and HIV coreceptor properties compared with wild-type CCR5 and G106R, an already analyzed mutant taken as another control. We observed that K26R displayed alteration in MIP1-beta/CCL4 and RANTES/CCL5 ligand binding and exhibited a slightly decrease for HIV coreceptor properties.

New CCR5 variants associated with reduced HIV coreceptor function in southeast Asia.

BACKGROUND: Despite multiple exposure to HIV-1, some individuals remain uninfected. This resistance has been associated with homozygosity for a 32 base pair deletion in the gene for the CCR5 receptor. This variant occurs frequently in Caucasians but is extremely rare in Asians or Africans. OBJECTIVE: To identify variations in CCR5 receptor gene that affect susceptibility to HIV infection in non-Caucasians. METHODS: CCR5 coding region polymorphisms were screened in three groups of Vietnamese subjects: 47 HIV-1 infected intravascular drug users, 50 highly HIV-1-exposed but seronegative intravascular drug users and 37 HIV-1-unexposed seronegative individuals. DNA was analysed by denaturing high performance liquid chromatography; this was followed by examination of the biochemical and HIV coreceptor properties of the coding regions. RESULTS: Five CCR5 coding region variants were identified in this Vietnamese population. The S185R, I254T and C269F mutations have not been previously described; G106R and R223Q have already been found in other Asian populations, but the functional properties of G106R is not known. These variants differed in biochemical and HIV coreceptor properties. S185R and I254T variants had receptor and coreceptor activities comparable to that of the wild type, whereas C269F and G106R behaved differently. This latter pair are poorly expressed at the cell surface, weakly bind macrophage inflammatory protein 1beta (CCL4) and RANTES (CCL5), and display reduced HIV-1 coreceptor efficiency. CONCLUSIONS: Among the five CCR5 variants found in this Vietnamese population, G106R and C269F displayed significant modifications of their receptor and coreceptor properties, which may contribute to susceptibility to HIV-1 infection and/or disease progression within this population.

A triple-mutated allele of granzyme B incapable of inducing apoptosis.

Granzyme B (GzmB) is a serine protease involved in many pathologies, including viral infections, autoimmunity, transplant rejection, and antitumor immunity. To measure the extent of genetic variation in GzmB, we screened the GzmB gene for polymorphisms and defined a frequently represented triple-mutated GzmB allele. In this variant, three amino acids of the mature protein Q(48)P(88)Y(245) are mutated to R(48)A(88)H(245). In CD8(+) cytotoxic T lymphocytes, GzmB was expressed at similar levels in QPY homozygous, QPY/RAH heterozygous, and RAH homozygous individuals, demonstrating that RAH GzmB is a stable protein. Active RAH GzmB expressed in glioblastoma cell lines displayed proteolytic activity, but in contrast to QPY GzmB, it did not accumulate in the nucleus and was unable to induce Bid cleavage, cytochrome c release, or apoptosis. Molecular modeling showed that the three amino acid substitutions clustered near the C-terminal alpha-helix of the protein, indicating that this region of the protein may be involved in the intracellular targeting of GzmB. The triple-mutated GzmB allele that we describe appears to be incapable of inducing apoptosis in tumor cell lines, and its presence could, therefore, influence both the prognosis of cancer patients and the success rates of antitumor cellular immunotherapy.