Vaccination with an HIV T-cell immunogen induces alterations in the mouse gut microbiota

The gut microbiota is emerging as a crucial factor modulating vaccine responses; however, few studies have investigated if vaccines, in turn, can alter the microbiota and to what extent such changes may improve vaccine efficacy. To understand the effect of T-cell vaccination on the gut microbiome, we administered an HIV-1 T-cell immunogen (HTI arm) or PBS (control, Mock arm) to C57Bl/6 mice following a heterologous prime-boost scheme. The longitudinal dynamics of the mice gut microbiota was characterized by 16 S ribosomal RNA sequencing in fecal samples collected from cages, as well as from three gut sections (cecum, small and large intestine). Serum and spleen cells were obtained at the last time point of the study to assess immune correlates using IFNγ ELISPOT and cytokine Luminex ® assays. Compared with Mock, HTI-vaccinated mice were enriched in Clostridiales genera (Eubacterium xylanophilum group, Roseburia and Ruminococcus) known as primary contributors of anti-inflammatory metabolites, such as short-chain fatty acids. Such shift was observed after the first HTI dose and remained throughout the study follow-up (18 weeks). However, the enriched Clostridiales genera were different between feces and gut sections. The abundance of bacteria enriched in vaccinated animals positively correlated with HTI-specific T-cell responses and a set of pro-inflammatory cytokines, such as IL-6. This longitudinal analysis indicates that, in mice, T-cell vaccination may promote an increase in gut bacteria known to produce anti-inflammatory molecules, which in turn correlate with proinflammatory cytokines, suggesting an adaptation of the gut microbial milieu to T-cell-induced systemic inflammation

Sudden spleen rupture in a Plasmodium vivax-infected patient undergoing malaria treatment

BACKGROUND: Splenomegaly is one of the most common features of malaria. However, spontaneous splenic rupture, although unusual, represents a severe complication often leading to death. It is mostly seen in acute infection and primary attack, and it is most commonly associated with Plasmodium vivax. Here, a case of spontaneous splenic rupture diagnosed with a portable ultrasound apparatus shortly after starting treatment and with recurrent parasitaemia after splenectomy, is reported. CASE DESCRIPTION: In November 2015, a 45-year-old Brazilian man presented to the hospital in Manaus with fever, headache and myalgia. He was diagnosed with P. vivax malaria and, after a normal G6PD test, he started treatment with chloroquine and primaquine and was discharged. Two days later, he went back to the hospital with abdominal pain, dyspnea, dry cough, pallor, oliguria and fever. Using a portable ultrasound, he was diagnosed of rupture of the spleen, which was removed by emergency surgery. After this episode, he suffered two more malaria episodes with high parasitaemia at approximately 2-month intervals. DNA from different portions of the spleen was extracted and a qualitative PCR was performed to detect P. vivax. CONCLUSIONS: The splenic rupture suffered by this patient occurred 2 days after starting the treatment. Having a portable ultrasound apparatus may have saved the patient's life, as it revealed a haemorrhage needing an urgent surgery. Parasites were detected by PCR in the extracted spleen. This patient suffered two more vivax malaria diagnosed episodes in spite of receiving and completing treatment with chloroquine and primaquine for each clinical attack. Splenic rupture during acute malaria is uncommon, but it is likely underdiagnosed and underreported, because the lack of means and equipment hinders diagnostic confirmation, especially in endemic areas

Spleen-Dependent Immune Protection Elicited by CpG Adjuvanted Reticulocyte-Derived Exosomes from Malaria Infection Is Associated with Changes in T cell Subsets' Distribution

Added corrigendum published in 2017-01-17 https://doi.org/10.3389/fcell.2016.00153Reticulocyte-derived exosomes (rex) are 30-100 nm membrane vesicles of endocytic origin released during the maturation of reticulocytes to erythrocytes upon fusion of multivesicular bodies with the plasma membrane. Combination of CpG-ODN with rex obtained from BALB/c mice infected with the reticulocyte-prone non-lethal P. yoelii 17X malaria strain (rexPy), had been shown to induce survival and long lasting protection. Here, we show that splenectomized mice are not protected upon rexPy+CpG inmunizations and that protection is restored upon passive transfer of splenocytes obtained from animals immunized with rexPy+CpG. Notably, rexPy immunization of mice induced changes in PD1- memory T cells with effector phenotype. Proteomics analysis of rexPy confirmed their reticulocyte origin and demonstrated the presence of parasite antigens. Our studies thus prove, for what we believe is the first time, that rex from reticulocyte-prone malarial infections are associated with splenic long-lasting memory responses. To try extrapolating these data to human infections, in vitro experiments with spleen cells of human transplantation donors were performed. Plasma-derived exosomes from vivax malaria patients (exPv) were actively uptaken by human splenocytes and stimulated spleen cells leading to changes in T cell subsets

Probiotic effects on immunity and microbiome in HIV-1 discordant patients

Some HIV-1 infected patients are unable to completely recover normal CD4+ T-cell (CD4+) counts after achieving HIV-1 suppression with combined Antiretroviral Therapy (cART), hence being classified as immuno-discordant. The human microbiome plays a crucial role in maintaining immune homeostasis and is a potential target towards immune reconstitution. RECOVER (NCT03542786) was a double-blind placebo-controlled clinical trial designed to evaluate if the novel probiotic i3.1 (AB-Biotics, Sant Cugat del Vallès, Spain) was able to improve immune reconstitution in HIV-1 infected immuno-discordant patients with stable cART and CD4+ counts <500 cells/mm3. The mixture consisted of two strains of L. plantarum and one of P. acidilactici, given with or without a fiber-based prebiotic. 71 patients were randomized 1:2:2 to Placebo, Probiotic or probiotic + prebiotic (Synbiotic), and were followed over 6 months + 3-month washout period, in which changes on systemic immune status and gut microbiome were evaluated. Primary endpoints were safety and tolerability of the investigational product. Secondary endpoints were changes on CD4+ and CD8+ T-cell (CD8+) counts, inflammation markers and faecal microbiome structure, defined by alpha diversity (Gene Richness), beta diversity (Bray-Curtis) and functional profile. Comparisons across/within groups were performed using standard/paired Wilcoxon test, respectively. Adverse event (AE) incidence was similar among groups (53%, 33%, and 55% in the Placebo, Probiotic and Synbiotic groups, respectively, the most common being grade 1 digestive AEs: flatulence, bloating and diarrhoea. Two grade 3 AEs were reported, all in the Synbiotic group: abdominal distension (possibly related) and malignant lung neoplasm (unrelated), and 1 grade 4 AE in the Placebo: hepatocarcinoma (unrelated). Synbiotic exposure was associated with a higher increase in CD4+/CD8+ T-cell (CD4/CD8) ratio at 6 months vs baseline (median=0.76(IQR=0.51) vs 0.72(0. 45), median change= 0.04(IQR=0.19), p = 0.03). At month 9, the Synbiotic group had a significant increase in CD4/CD8 ratio (0.827(0.55) vs 0.825(0.53), median change = 0.04(IQR=0.15), p= 0.02) relative to baseline, and higher CD4+ counts (447 (157) vs. 342(73) counts/ml, p = 0.03), and lower sCD14 values (2.16(0.67) vs 3.18(0.8), p = 0.008) than Placebo. No effect in immune parameters was observed in the Probiotic arm. None of the two interventions modified microbial gene richness (alpha diversity). However, intervention as categorical variable was associated with slight but significant effect on Bray-Curtis distance variance (Adonis R2 = 0.02, p = 0.005). Additionally, at month 6, Synbiotic intervention was associated with lower pathway abundances vs Placebo of Assimilatory Sulphate Reduction (8.79·10 -6 (1.25·10 -5) vs. 1.61·10 -5 (2.77·10 -5), p = 0.03) and biosynthesis of methionine (2.3·10 -5 (3.17·10 -5) vs. 4·10 -5 (5.66·10 -5), p = 0.03) and cysteine (1.83·10 -5 (2.56·10 -5) vs. 3.3·10 -5 (4.62·10 -5), p = 0.03). At month 6, probiotic detection in faeces was associated with significant decreases in C Reactive Protein (CRP) vs baseline (11.1(22) vs. 19.2(66), median change= -2.7 (13.2) ug/ml, p = 0.04) and lower IL-6 values (0.58(1.13) vs. 1.17(1.59) ug/ml, p = 0.02) when compared with samples with no detectable probiotic. No detection of the probiotic was associated with higher CD4/CD8 ratio at month 6 vs baseline (0.718(0.57) vs. 0.58(0.4), median change = 0.4(0.2), p = 0.02). After washout, probiotic non-detection was also associated with a significant increase in CD4+ counts (457(153) vs. 416(142), median change = 45(75), counts/ml, p = 0.005) and CD4/CD8 ratio (0.67(0.5) vs 0.59(0.49), median change = 0.04 (0.18), p = 0.02). A synbiotic intervention with L. plantarum and P. acidilactici was safe and led to small increases in CD4/CD8 ratio and minor reductions in sCD14 of uncertain clinical significance. A probiotic with the same composition was also safe but did not achieve any impact on immune parameters or faecal microbiome composition

Probiotic effects on immunity and microbiome in HIV-1 discordant patients

BackgroundSome HIV-1 infected patients are unable to completely recover normal CD4+ T-cell (CD4+) counts after achieving HIV-1 suppression with combined Antiretroviral Therapy (cART), hence being classified as immuno-discordant. The human microbiome plays a crucial role in maintaining immune homeostasis and is a potential target towards immune reconstitution.SettingRECOVER (NCT03542786) was a double-blind placebo-controlled clinical trial designed to evaluate if the novel probiotic i3.1 (AB-Biotics, Sant Cugat del Vallès, Spain) was able to improve immune reconstitution in HIV-1 infected immuno-discordant patients with stable cART and CD4+ counts &lt;500 cells/mm3. The mixture consisted of two strains of L. plantarum and one of P. acidilactici, given with or without a fiber-based prebiotic.Methods71 patients were randomized 1:2:2 to Placebo, Probiotic or probiotic + prebiotic (Synbiotic), and were followed over 6 months + 3-month washout period, in which changes on systemic immune status and gut microbiome were evaluated. Primary endpoints were safety and tolerability of the investigational product. Secondary endpoints were changes on CD4+ and CD8+ T-cell (CD8+) counts, inflammation markers and faecal microbiome structure, defined by alpha diversity (Gene Richness), beta diversity (Bray-Curtis) and functional profile. Comparisons across/within groups were performed using standard/paired Wilcoxon test, respectively.ResultsAdverse event (AE) incidence was similar among groups (53%, 33%, and 55% in the Placebo, Probiotic and Synbiotic groups, respectively, the most common being grade 1 digestive AEs: flatulence, bloating and diarrhoea. Two grade 3 AEs were reported, all in the Synbiotic group: abdominal distension (possibly related) and malignant lung neoplasm (unrelated), and 1 grade 4 AE in the Placebo: hepatocarcinoma (unrelated). Synbiotic exposure was associated with a higher increase in CD4+/CD8+ T-cell (CD4/CD8) ratio at 6 months vs baseline (median=0.76(IQR=0.51) vs 0.72(0. 45), median change= 0.04(IQR=0.19), p = 0.03). At month 9, the Synbiotic group had a significant increase in CD4/CD8 ratio (0.827(0.55) vs 0.825(0.53), median change = 0.04(IQR=0.15), p= 0.02) relative to baseline, and higher CD4+ counts (447 (157) vs. 342(73) counts/ml, p = 0.03), and lower sCD14 values (2.16(0.67) vs 3.18(0.8), p = 0.008) than Placebo. No effect in immune parameters was observed in the Probiotic arm. None of the two interventions modified microbial gene richness (alpha diversity). However, intervention as categorical variable was associated with slight but significant effect on Bray-Curtis distance variance (Adonis R2 = 0.02, p = 0.005). Additionally, at month 6, Synbiotic intervention was associated with lower pathway abundances vs Placebo of Assimilatory Sulphate Reduction (8.79·10-6 (1.25·10-5) vs. 1.61·10-5 (2.77·10-5), p = 0.03) and biosynthesis of methionine (2.3·10-5 (3.17·10-5) vs. 4·10-5 (5.66·10-5), p = 0.03) and cysteine (1.83·10-5 (2.56·10-5) vs. 3.3·10-5 (4.62·10-5), p = 0.03). At month 6, probiotic detection in faeces was associated with significant decreases in C Reactive Protein (CRP) vs baseline (11.1(22) vs. 19.2(66), median change= -2.7 (13.2) ug/ml, p = 0.04) and lower IL-6 values (0.58(1.13) vs. 1.17(1.59) ug/ml, p = 0.02) when compared with samples with no detectable probiotic. No detection of the probiotic was associated with higher CD4/CD8 ratio at month 6 vs baseline (0.718(0.57) vs. 0.58(0.4), median change = 0.4(0.2), p = 0.02). After washout, probiotic non-detection was also associated with a significant increase in CD4+ counts (457(153) vs. 416(142), median change = 45(75), counts/ml, p = 0.005) and CD4/CD8 ratio (0.67(0.5) vs 0.59(0.49), median change = 0.04 (0.18), p = 0.02).ConclusionA synbiotic intervention with L. plantarum and P. acidilactici was safe and led to small increases in CD4/CD8 ratio and minor reductions in sCD14 of uncertain clinical significance. A probiotic with the same composition was also safe but did not achieve any impact on immune parameters or faecal microbiome composition

A cluster-randomized trial of hydroxychloroquine for prevention of Covid-19

Background: current strategies for preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are limited to nonpharmacologic interventions. Hydroxychloroquine has been proposed as a postexposure therapy to prevent coronavirus disease 2019 (Covid-19), but definitive evidence is lacking. Methods: we conducted an open-label, cluster-randomized trial involving asymptomatic contacts of patients with polymerase-chain-reaction (PCR)-confirmed Covid-19 in Catalonia, Spain. We randomly assigned clusters of contacts to the hydroxychloroquine group (which received the drug at a dose of 800 mg once, followed by 400 mg daily for 6 days) or to the usual-care group (which received no specific therapy). The primary outcome was PCR-confirmed, symptomatic Covid-19 within 14 days. The secondary outcome was SARS-CoV-2 infection, defined by symptoms compatible with Covid-19 or a positive PCR test regardless of symptoms. Adverse events were assessed for up to 28 days. Results: the analysis included 2314 healthy contacts of 672 index case patients with Covid-19 who were identified between March 17 and April 28, 2020. A total of 1116 contacts were randomly assigned to receive hydroxychloroquine and 1198 to receive usual care. Results were similar in the hydroxychloroquine and usual-care groups with respect to the incidence of PCR-confirmed, symptomatic Covid-19 (5.7% and 6.2%, respectively; risk ratio, 0.86 [95% confidence interval, 0.52 to 1.42]). In addition, hydroxychloroquine was not associated with a lower incidence of SARS-CoV-2 transmission than usual care (18.7% and 17.8%, respectively). The incidence of adverse events was higher in the hydroxychloroquine group than in the usual-care group (56.1% vs. 5.9%), but no treatment-related serious adverse events were reported. Conclusions: postexposure therapy with hydroxychloroquine did not prevent SARS-CoV-2 infection or symptomatic Covid-19 in healthy persons exposed to a PCR-positive case patient. (Funded by the crowdfunding campaign YoMeCorono and others; BCN-PEP-CoV2 ClinicalTrials.gov number, NCT04304053.)

Hydroxychloroquine for Early Treatment of Adults With Mild Coronavirus Disease 2019: A Randomized, Controlled Trial

No effective treatments for coronavirus disease 2019 (COVID-19) exist. We aimed to determine whether early treatment with hydroxychloroquine (HCQ) would be efficacious for outpatients with COVID-19.The authors thank Gerard Carot-Sans, PhD, for providing medical writing support during the revisions of the subsequent drafts of the manuscript; the personnel from the Fights Aids and Infectious Diseases Foundation for their support in administration, human resources and supply chain management; Eric Ubals (Pierce AB) and Òscar Palao (Opentic) for website and database management; Óscar Camps and OpenArms nongovernmental organization for nursing home operations; and Anna Valentí and the Hospital Germans Trias i Pujol Human Resources Department for telephone monitoring. We thank Consorci Sanitari del Maresme, Centre Sociosanitari El Carme, l'Hospital General de Granollers and occupational hazards department of Hospital Germans Trias i Pujol for their contribution with patient enrollment. We are very grateful to Marc Clotet and Natalia Sánchez who coordinated the JoEmCorono crowd-funding campaign. We thank the Hospital Germans Trias Pujol Institutional Review Board and the Spanish Agency of Medicines and Medical Devices for their prompt action for consideration and approvals to the protocol. Financial support. This work was mainly supported by the crowd-funding campaign JoEmCorono (https://www.yomecorono.com/) with contributions from more than 72 000 citizens and corporations. The study also received financial support from Laboratorios Rubió, Laboratorios Gebro Pharma, Zurich Seguros, SYNLAB Barcelona, and Generalitat de Catalunya. Laboratorios Rubió also contributed to the study with the required doses of hydroxychloroquine (Dolquine®). Foundation Dorneur partly funded lab equipment at Irsi-Caixa.Peer reviewe

Lamivudine, a reverse transcriptase inhibitor, rescues cognitive deficits in a mouse model of down syndrome

An elevated activity of retrotransposons is increasingly recognized to be implicated in a wide range of neurodegenerative and neurodevelopmental diseases. Down syndrome (DS) is the most common genetic disorder associated with intellectual disability and a genetic form of Alzheimer's disease. For this reason, we hypothesized that treatment with reverse transcriptase inhibitors could ameliorate DS phenotypes. In this proof of concept study, we treated trisomic (Ts65Dn) mice, a model of DS, with lamivudine, a reverse transcriptase inhibitor. We detected a significant improvement of neurobehavioural phenotypes, and a complete rescue of the hippocampal-dependent recognition memory upon treatment with lamivudine. Despite clinical studies in patients with DS are warranted, this study lays the groundwork for a novel and actionable therapeutic approach.Agencia Estatal de Investigación. Grant Number: PID2019-110755RB-I00/AEI/10.13039/501100011033. Horizon 2020 Framework Programme. Grant Number: 84807

Sudden spleen rupture in a Plasmodium vivax-infected patient undergoing malaria treatment

BACKGROUND: Splenomegaly is one of the most common features of malaria. However, spontaneous splenic rupture, although unusual, represents a severe complication often leading to death. It is mostly seen in acute infection and primary attack, and it is most commonly associated with Plasmodium vivax. Here, a case of spontaneous splenic rupture diagnosed with a portable ultrasound apparatus shortly after starting treatment and with recurrent parasitaemia after splenectomy, is reported. CASE DESCRIPTION: In November 2015, a 45-year-old Brazilian man presented to the hospital in Manaus with fever, headache and myalgia. He was diagnosed with P. vivax malaria and, after a normal G6PD test, he started treatment with chloroquine and primaquine and was discharged. Two days later, he went back to the hospital with abdominal pain, dyspnea, dry cough, pallor, oliguria and fever. Using a portable ultrasound, he was diagnosed of rupture of the spleen, which was removed by emergency surgery. After this episode, he suffered two more malaria episodes with high parasitaemia at approximately 2-month intervals. DNA from different portions of the spleen was extracted and a qualitative PCR was performed to detect P. vivax. CONCLUSIONS: The splenic rupture suffered by this patient occurred 2 days after starting the treatment. Having a portable ultrasound apparatus may have saved the patient's life, as it revealed a haemorrhage needing an urgent surgery. Parasites were detected by PCR in the extracted spleen. This patient suffered two more vivax malaria diagnosed episodes in spite of receiving and completing treatment with chloroquine and primaquine for each clinical attack. Splenic rupture during acute malaria is uncommon, but it is likely underdiagnosed and underreported, because the lack of means and equipment hinders diagnostic confirmation, especially in endemic areas