Heterogeneity of Latency Establishment in the Different Human CD4+ T Cell Subsets Stimulated with IL-15.

HIV integrates into the host genome, creating a viral reservoir of latently infected cells that persists despite effective antiretroviral treatment. CD4-positive (CD4+) T cells are the main contributors to the HIV reservoir. CD4+ T cells are a heterogeneous population, and the mechanisms of latency establishment in the different subsets, as well as their contribution to the reservoir, are still unclear. In this study, we analyzed HIV latency establishment in different CD4+ T cell subsets stimulated with interleukin 15 (IL-15), a cytokine that increases both susceptibility to infection and reactivation from latency. Using a dual-reporter virus that allows discrimination between latent and productive infection at the single-cell level, we found that IL-15-treated primary human CD4+ T naive and CD4+ T stem cell memory (TSCM) cells are less susceptible to HIV infection than CD4+ central memory (TCM), effector memory (TEM), and transitional memory (TTM) cells but are also more likely to harbor transcriptionally silent provirus. The propensity of these subsets to harbor latent provirus compared to the more differentiated memory subsets was independent of differential expression of pTEFb components. Microscopy analysis of NF-κB suggested that CD4+ T naive cells express smaller amounts of nuclear NF-κB than the other subsets, partially explaining the inefficient long terminal repeat (LTR)-driven transcription. On the other hand, CD4+ TSCM cells display similar levels of nuclear NF-κB to CD4+ TCM, CD4+ TEM, and CD4+ TTM cells, indicating the availability of transcription initiation and elongation factors is not solely responsible for the inefficient HIV gene expression in the CD4+ TSCM subset. IMPORTANCE The formation of a latent reservoir is the main barrier to HIV cure. Here, we investigated how HIV latency is established in different CD4+ T cell subsets in the presence of IL-15, a cytokine that has been shown to efficiently induce latency reversal. We observed that, even in the presence of IL-15, the less differentiated subsets display lower levels of productive HIV infection than the more differentiated subsets. These differences were not related to different expression of pTEFb, and modest differences in NF-κB were observed for CD4+ T naive cells only, implying the involvement of other mechanisms. Understanding the molecular basis of latency establishment in different CD4+ T cell subsets might be important for tailoring specific strategies to reactivate HIV transcription in all the CD4+ T subsets that compose the latent reservoir.

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.

Anakinra combined with methylprednisolone in patients with severe COVID-19 pneumonia and hyperinflammation: An observational cohort study.

BACKGROUND: Immunomodulants have been proposed to mitigate severe acute respiratory syndrome coronavirus 2-induced cytokine storm, which drives acute respiratory distress syndrome in coronavirus disease 2019 (COVID-19). OBJECTIVE: We sought to determine efficacy and safety of the association of IL-1 receptor antagonist anakinra plus methylprednisolone in severe COVID-19 pneumonia with hyperinflammation. METHODS: A secondary analysis of prospective observational cohort studies was carried out at an Italian tertiary health care facility. COVID-19 patients consecutively hospitalized (February 25, 2020, to March 30, 2020) with hyperinflammation (ferritin ≥1000 ng/mL and/or C-reactive protein >10 mg/dL) and respiratory failure (oxygen therapy from 0.4 FiO2 Venturi mask to invasive mechanical ventilation) were evaluated to investigate the effect of high-dose anakinra plus methylprednisolone on survival. Patients were followed from study inclusion to day 28 or death. Crude and adjusted (sex, age, baseline PaO2:FiO2 ratio, Charlson index, baseline mechanical ventilation, hospitalization to inclusion lapse) risks were calculated (Cox proportional regression model). RESULTS: A total of 120 COVID-19 patients with hyperinflammation (median age, 62 years; 80.0% males; median PaO2:FiO2 ratio, 151; 32.5% on mechanical ventilation) were evaluated. Of these, 65 were treated with anakinra and methylprednisolone and 55 were untreated historical controls. At 28 days, mortality was 13.9% in treated patients and 35.6% in controls (Kaplan-Meier plots, P = .005). Unadjusted and adjusted risk of death was significantly lower for treated patients compared with controls (hazard ratio, 0.33, 95% CI, 0.15-0.74, P = .007, and HR, 0.18, 95% CI, 0.07-0.50, P = .001, respectively). No significant differences in bloodstream infections or laboratory alterations were registered. CONCLUSIONS: Treatment with anakinra plus methylprednisolone may be a valid therapeutic option in COVID-19 patients with hyperinflammation and respiratory failure, also on mechanical ventilation. Randomized controlled trials including the use of either agent alone are needed to confirm these results.

Contribution of transgender sex workers to the complexity of the HIV-1 epidemic in the metropolitan area of Milan.

OBJECTIVES: Transgender people are disproportionately affected by the HIV-1 epidemic. We evaluated the origin of HIV-1 variants carried by South American transgenders living in Milan by combining accurate phylogenetic methods and epidemiological data. METHODS: We collected 156 HIV-1 pol sequences obtained from transgender patients engaged in sex work (TSWs) followed between 1999 and 2015 at L. Sacco Hospital, Milan, Italy. Phylogenetic analyses were conducted by HIV-TRACE, MrBayes, MacClade and Beast programs. Reference sequences were retrieved from Los Alamos and local databases. Last negative testing or proxy data from clinical records of infected individuals were used to investigate the country of infection. RESULTS: Among South American TSWs, the most represented HIV-1 subtypes were B (70.5%), F1 (12.8%) and C (4.4%). Gene flow migrations of B subtype indicated significant fluxes from TSWs to Italians (21.3%) belonging to all risk groups (26.4% to heterosexuals (HEs), 18.9% to men who have sex with men (MSM), 15.1% to injecting drug users). The largest proportion of bidirectional fluxes were observed between Italians and TSWs (24.6%). For F1 subtype, bidirectional viral fluxes involved TSWs and Italians (7.1% and 14.3%), and a similar proportion of fluxes linked TSWs and Italian HEs or MSM (both 15.8%). Significant fluxes were detected from Italians to TSWs for subtype C involving both MSM (30%) and HEs (40%). Country of HIV-1 acquisition was identified for 72 subjects; overall, the largest proportion of patients with B subtype (73.5%) acquired HIV-1 infection in South America. CONCLUSIONS: Our results indicated that South American transgenders largely contribute to the heterogeneity of HIV-1 variants in our country. The high number of clusters based on all subtypes indicated numerous transmission chains in which TSWs were constantly intermixed with HEs and MSM. Our results strongly advocate interventions to facilitate prevention, diagnosis and HIV-1 care continuum among transgender people.

COVID-19 multidisciplinary high dependency unit: the Milan model.

COVID-19 is a complex and heterogeneous disease. The pathogenesis and the complications of the disease are not fully elucidated, and increasing evidence shows that SARS-CoV-2 causes a systemic inflammatory disease rather than a pulmonary disease. The management of hospitalized patients in COVID-19 dedicated units is advisable for segregation purpose as well as for infection control. In this article we present the standard operating procedures of our COVID-19 high dependency unit of the Policlinico Hospital, in Milan. Our high dependency unit is based on a multidisciplinary approach. We think that the multidisciplinary involvement of several figures can better identify treatable traits of COVID-19 disease, early identify patients who can quickly deteriorate, particularly patients with multiple comorbidities, and better manage complications related to off-label treatments. Although no generalizable to other hospitals and different healthcare settings, we think that our experience and our point of view can be helpful for countries and hospitals that are now starting to face the COVID-19 outbreak.

Multidrug-Resistant Gram-Negative Bacteria Decolonization in Immunocompromised Patients: A Focus on Fecal Microbiota Transplantation.

Antimicrobial resistance is an important issue for global health; in immunocompromised patients, such as solid organ and hematological transplant recipients, it poses an even bigger threat. Colonization by multidrug-resistant (MDR) bacteria was acknowledged as a strong risk factor to subsequent infections, especially in individuals with a compromised immune system. A growing pile of studies has linked the imbalance caused by the dominance of certain taxa populating the gut, also known as intestinal microbiota dysbiosis, to an increased risk of MDR bacteria colonization. Several attempts were proposed to modulate the gut microbiota. Particularly, fecal microbiota transplantation (FMT) was successfully applied to treat conditions like Clostridioides difficile infection and other diseases linked to gut microbiota dysbiosis. In this review we aimed to provide a look at the data gathered so far on FMT, focusing on its possible role in treating MDR colonization in the setting of immunocompromised patients and analyzing its efficacy and safety.

Local and global spatio-temporal dynamics of HIV-1 subtype F1.

Previous studies have attempted to explore the origin of the F1 subtype, but the precise origin of the Romanian and South American F1 variants remains controversial. As the F1 subtype is the most frequent non-B variant among Europeans residing in Italy, the aim of this study was to estimate its phylogeography in order to reconstruct its origin and route of dispersion. The phylogeographical analyses, which were made using the Bayesian Markov Chain Monte Carlo approach and BEAST software, revealed two significant clades: the first included all of the Romanian strains together with a few Italian and four African isolates; the second encompassed all of the South American sequences and the large majority of Italian variants. By putting the African reference sequences into two discrete groups based on specific countries, phylogeographic analysis indicated that the F1 epidemic originated in Cameroon/Democratic Republic of Congo in the early 1940s, and was exported to South America 10 years later. Subsequently, the F1 virus spread to Angola and, from there, was exported to Romania in the early 1960s. It reached Italy in the 1970s from South America and Romania. The South American and Romanian variants of F1 have different African countries of origin and different temporal spreads. The South American variant seems to be characterized by multiple introduction events, whereas the Romanian strain probably spread as a result of a single entry. Two different pathways from South America and Romania led the F1 variant to Italy in the 1970s.

Phylogenetic analysis provides evidence of interactions between Italian heterosexual and South American homosexual males as the main source of national HIV-1 subtype C epidemics.

The HIV-1 clade C is prevalent worldwide and spread from Africa to South East Asia and South America early in the course of the epidemic. As a consequence of migration waves about 13% of the Italian HIV-1 epidemic is sustained by this clade. Two hundred fifty-four C pol sequences from the Italian ARCA database collected during 1997-2011 were analyzed. Epidemiological networks and geographical fluxes were identified through phylogeny using Bayesian approaches. Patients' country of origin was Italy, Africa, South America, and South East Asia for 44.9%, 23.6%, 4.7%, and 1.6%, respectively. Heterosexuals and men having sex with men accounted for 83.2% and 16.8%, respectively. Modality of infection was distributed differently: heterosexuals were largely prevalent among Italians (84.1%) and Africans (95.3%), while men having sex with men predominated among South Americans (66.7%). Eight significant clusters encompassing 111 patients (43.7%) were identified. Comparison between clustering and non-clustering patients indicated significant differences in country of origin, modality of infection and gender. Men having sex with men were associated to a higher probability to be included in networks (70% for men having sex with men vs. 30.3% for heterosexuals). Phylogeography highlighted two significant groups. One contained Indian strains and the second encompassed South Americans and almost all Italian strains. Phylogeography indicated that the spread of C subtype among Italians is related to South American variant. Although Italian patients mainly reported themselves as heterosexuals, homo-bisexual contacts were likely their source of infection. Phylogenetic monitoring is warranted to guide public health interventions aimed at controlling HIV infection.

Impact of COVID-19 pandemic on retention in care of native and migrant people with HIV in the ICONA cohort.

BACKGROUND: COVID-19 pandemic challenged the UNAIDS 90-90-90 targets. How the COVID-19 pandemic affected HIV retention in care and whether it has disproportionally affected migrant people with HIV (PWH) remained to be investigated. METHODS: PWH in ICONA Cohort in follow-up in each of the study periods were included: 01/09/2019-29/02/2020 (pandemic period) and 01/03/2018-31/08/2018 (historical period, as a control). Risk of temporary loss to follow-up (LTFU, defined as no data recorded for a person for one year) was analyzed by logistic regression, with migrant status as the main exposure variable. Difference in difference (DID) analysis was applied to evaluate the effect of COVID-19 pandemic in the different risk of LTFU between natives and migrants. RESULTS: 8864 (17.1% migrants) and 8071 (16.8% migrants) PWH constituted the pandemic and the historical period population, respectively. Proportion of PWH defined as LTFU in the pandemic period was 10.5% in native and 19.6% in migrant PWH. After controlling for age, sex and geographical location of enrolling site, risk of temporary LTFU was higher for migrants than native PWH [adjusted odds ratio 1.85 (95%CI 1.54-2.22)] in pandemic period. In PWH contributing to both periods, LTFU was 9.0% (95% CI 8.3-9.8) in natives vs 17.0% (95% CI 14.7-19.4) in migrants during the pandemic. Instead, LTFU was 1.2% (95%CI 0.9, 1.5) in natives vs 2.2% (95% CI 1.3-3.1) in migrants during the historical period, with a resulting DID of 7.0% (95% CI 4.4-9.6). CONCLUSIONS: A greater proportion of LTFU in migrant PWH was observed in both periods, which remained unaltered over time. Interventions to reduce LTFU of migrants are necessary.

Preventing HIV mother-to-child transmission in a vertically infected pregnant woman with multiclass drug resistance, role of bis-in-die dolutegravir and neonatal AZT prophylaxis: A case report.

A suppressive antiretroviral therapy (ART) is necessary to prevent mother-to-child transmission (MTCT) of HIV during pregnancy. During this period, it is recommended to continue an ongoing safe and suppressive regimen, but history of multiclass drug-resistance (MDR) might need tailored, uncommon approaches posing tolerability and toxicity issues. This is the case of a 33 years of age, vertically infected woman with MDR HIV infection suppressed on a darunavir/cobicistat + atazanavir regimen switched during pregnancy to lamivudine + darunavir/ritonavir + dolutegravir 50 mg bis-in-die, maintaining complete viral suppression and delivering via caesarian section and without zidovudine (AZT) intrapartum prophylaxis a healthy HIV-negative newborn who received AZT post-exposure prophylaxis and showed regular growth patterns up to 2 years. Our case shows how archived MDR might complicate the preservation of HIV RNA suppression and highlights the importance of a tailored, multidisciplinary approach for pregnant women with MDR HIV and their newborns.

Retrospective analysis of bacteraemia due to extended-spectrum beta-lactamase-producing Enterobacterales: the challenge of healthcare-associated infections.

Objectives: Healthcare-associated bacteraemia is defined as bacteraemia diagnosed ≤48 h after hospital admission in patients recently exposed to healthcare procedures or settings. It differs from hospital-acquired bacteraemia, which is diagnosed >48 h after hospital admission. Healthcare-associated bacteraemia is reported increasingly, often due to resistant pathogens including extended-spectrum beta-lactamase (ESBL) producers, representing a challenge to empirical treatment. This study aimed to assess the appropriateness of empirical treatment for ESBL bacteraemia at the authors' centre, to perform a descriptive analysis according to the mode of infection acquisition (community-acquired, healthcare-associated, hospital-acquired), and to assess the risk factors for mortality. Methods: A retrospective study on patients with ESBL bacteraemia was undertaken. Results: In total, 129 consecutive cases of bacteraemia due to ESBL producers were included in this study. Compared with community- and hospital-acquired bacteraemia, healthcare-associated bacteraemia affected older patients (P=0.001) and patients with higher Charlson Comorbidity Index scores (P=0.007), and was more frequently associated with piperacillin-tazobactam resistance (P=0.025) and multi-drug resistance (P=0.026). Overall, ineffective empirical treatment was common (42%). Factors associated with 30-day mortality were septic shock [odds ratio (OR) 7.096, 95% confidence interval (CI) 2.58-24.58], high Pitt score (OR 6.636, 95% CI 1.71-23.62) and unknown source of bacteraemia (OR 19.28, 95% CI 2.80-30.70). Conclusions: Antimicrobial stewardship interventions focusing on both in-hospital and community settings are advocated to better manage healthcare-associated infections due to ESBL producers.

High burden of transmitted HIV-1 drug resistance in Italian patients carrying F1 subtype.

BACKGROUND: Transmitted drug resistance (TDR) is mainly restricted to individuals carrying B subtype, with low prevalence among non-B subtypes when grouped together. Subtype F1 is the most frequent non-B variant found in subjects living in Italy, allowing a specific assessment of TDR associated with this clade. METHODS: We analysed pol sequences of HIV-1-positive individuals carrying the F1 variant included in the Antiretroviral Resistance Cohort Analysis database in the 1998-2009 period. Mutations were analysed with the Surveillance Drug Resistance Mutation and the International AIDS Society lists for naive and treated patients, respectively. RESULTS: Among 343 HIV-1-infected patients carrying an F1 subtype, resistance was evaluated in a subset of 221 patients whose treatment status was known (169 drug naive and 52 drug experienced). The prevalence of TDR was 15.4% (11.8% for nucleoside/nucleotide reverse transcriptase inhibitors, 6.5% for non-nucleoside reverse transcriptase inhibitors and 7.1% for protease inhibitors). Among the 169 naive patients, 75.1%, 10.1% and 7.1% were Italians, South Americans and Romanians, respectively. Heterosexuals were prevalent among Italians and Romanians, while men who have sex with men were predominant among South Americans. The overall frequency of TDR declined from 21.4% to 7.1% in the 1998-2009 period. Although no statistical difference was detected, the frequency of TDR was higher in South Americans (23.5%) compared with Italian and Romanian naive patients (15% and 8.3%, respectively). DISCUSSION: Our study shows a remarkable frequency of TDR in the F1 subtype-infected population. The high prevalence of TDR detected in South American subjects is linked to the homosexual route of infection. However, TDR was considerably high also in Italian subjects harbouring the F1 subtype, deserving careful monitoring.

Nocardia Infections in the Immunocompromised Host: A Case Series and Literature Review.

Nocardia is primarily considered an opportunistic pathogen and affects patients with impaired immune systems, solid-organ transplant recipients (SOTRs), and patients with haematologic malignancies. We present the cases of six patients diagnosed with nocardiosis at our center in the last two years, describing the various predisposing conditions alongside the clinical manifestation, the diagnostic workup, and the treatment course. Moreover, we propose a brief literature review on Nocardia infections in the immunocompromised host, focusing on SOTRs and haematopoietic stem cell transplantation recipients and highlighting risk factors, clinical presentations, the diagnostic tools available, and current treatment and prophylaxis guidelines.

Infectious events in patients treated with immune checkpoint inhibitors, chimeric antigen receptor T cells, and bispecific T-cell engagers: a review of registration studies.

BACKGROUND: Immunological treatments (immune checkpoint inhibitors [ICIs], chimeric antigen receptor T [CAR-T] cells, bispecific T-cell engagers [BiTEs]) have deeply changed the treatment of several cancers. However, the impact of these treatments on the risk of developing infections has not been completely ascertained yet. METHODS: We reviewed all the registration studies of currently approved ICIs, CAR-T cells, and BiTEs to collect all the reported infections. For each drug, we have generated a report with the infections occurring in at least 10% of the patients enrolled. RESULTS: The most frequently reported infections involving patients treated with ICIs involved the respiratory tract, including nasopharyngitis, upper respiratory tract infections, and pneumonia and the urinary tract. Those treated with CAR-T cells frequently reported the incidence of unspecified infections and infestations, bacterial infections, and viral infections. In patients treated with BiTEs, nasopharyngitis, pneumonia, and device-related infections were the most frequently reported conditions. CONCLUSIONS: A wide range of infections are reported in registration studies and clinical trials of ICIs, CAR-T cells, and BiTEs.

Pneumocystis jirovecii pneumonia in HIV-negative patients, a frequently overlooked problem. A case series from a large Italian center.

BACKGROUND AND OBJECTIVES: Pneumocystis jirovecii pneumonia (PCP) still has substantial morbidity and mortality. For non-HIV patients, the course of infection is severe, and management guidelines are relatively recent. We collected all PCP cases (European Organization for Research and Treatment of Cancer criteria) diagnosed in HIV-negative adult inpatients in 2019-2020 at our center in northern Italy. RESULTS: Of 20 cases, nine had microbiologic evidence of probable (real-time polymerase chain reaction, RT-PCR) and 11 proven (immunofluorescence) PCP on respiratory specimens. Half were female; the median age was 71.5 years; 14 of 20 patients had hematologic malignancies, five had autoimmune/hyperinflammatory disorders, and one had a solid tumor. RT-PCR cycle threshold (Ct) was 24-37 for bronchoalveolar lavage (BAL) and 32-39 for sputum; Ct was 24-33 on BAL proven cases. Of 20 cases, four received additional diagnoses on BAL. At PCP diagnosis, all patients were not on anti-pneumocystis prophylaxis. We retrospectively assessed prophylaxis indications: 9/20 patients had a main indication, 5/9 because of prednisone treatment ≥ 20 mg (or equivalents) for ≥4 weeks. All patients underwent antimicrobial treatment according to guidelines; 18/20 with concomitant corticosteroids. A total of 4/20 patients died within 28 days from diagnosis. CONCLUSION: Despite appropriate treatment, PCP is still associated to high mortality (20%) among non-HIV patients. Strict adherence to prophylaxis guidelines, awareness of gray areas, and prompt diagnosis can help manage this frequently overlooked infection.

Anti-spike antibodies and neutralising antibody activity in people living with HIV vaccinated with COVID-19 mRNA-1273 vaccine: a prospective single-centre cohort study.

BACKGROUND: Vaccines against COVID-19 are a powerful tool to control the current SARS-CoV-2 pandemic. A thorough description of their immunogenicity among people living with HIV (PLWHIV) is necessary. We aimed to assess the immunogenicity of the mRNA-1273 vaccine among PLWHIV. METHODS: In this prospective cohort, adult PLWHIV outpatients were enrolled during the Italian vaccination campaign. Enrolment was allowed irrespective of ongoing combination antiretroviral therapy (ART), plasma HIV viral load and CD4+ T cell count. A two-dose regimen of mRNA-1273, with administrations performed 28 days apart, was employed. The primary outcomes were anti-spike (anti-S) antibody titres and neutralising antibody activity, assessed 28 days after completing the vaccination schedule. A convenient sample of individuals not affected by HIV was also collected to serve as control (referred as healthy-donors, HDs). FINDINGS: We enrolled 71 PLWHIV, mostly male (84·5%), with a mean age of 47 years, a median CD4+ T cell count of 747·0 cells per µL and a median HIV viral load <50 copies/mL. COVID-19-experienced PLWHIV displayed higher anti-S antibody titres (p=0·0007) and neutralising antibody activity in sera (p=0·0007) than COVID-19-naïve PLWHIV. When stratified according to CD4+ T cell count (<350 cells/µL, 350-500 cells/µL, >500 cells/µL), anti-S antibody titres (6/71, median 2173 U/mL [IQR 987-4109]; 7/71, 5763 IU/mL [IQR 4801->12500]; 58/71, 2449 U/mL [IQR 1524-5704]) were not lower to those observed among HDs (10, median 1425 U/mL [IQR 599-6131]). In addition, neutralising antibody activity, stratified according to the CD4+ T cell count (6/71, median 1314 [IQR 606-2477]; 7/71, 3329 IU/mL [IQR 1905-10508]; 58/71, 1227 U/mL [IQR 761-3032]), was like those displayed by HDs (10, median 2112 U/mL [IQR 719-8889]). INTERPRETATION: In our cohort of PLWHIV with well-controlled ART, stable viral suppression and robust CD4+ T cell count, inoculation with mRNA-1273 vaccine given 4 weeks apart produced detectable humoral immune response, similar to individuals without HIV infection, supporting vaccination in PLWHIV. FUNDING: This study was partially supported by Italian Ministry of Health Ricerca Corrente 2021, by Intesa San Paolo COVID-19 emergency 2020 funds, and by Fondazione Cariplo Grant (INNATE-CoV).

Mini Review Immunological Consequences of Immunization With COVID-19 mRNA Vaccines: Preliminary Results.

Background: BNT162b2 and mRNA-1273 are the two recently approved mRNA-based vaccines against COVID-19 which has shown excellent safety and efficacy. Preliminary data about specific and neutralizing antibodies is available covering the first 100 days after vaccination. Methods: We reviewed all the publications regarding the immunologic consequences of BNT162b2 and mRNA-1273 vaccination. A summary of specific antibodies concentration and neutralizing antibodies titers elicited by each vaccine is provided. Results: BNT162b2 and mRNA-1273 displayed a reassuring safety and efficacy profile, with the latter above 94%. They can elicit specific antibodies titers and neutralizing antibodies concentrations that are far superior from those observed among COVID-19 human convalescent serum, across a wide span of age, for at least 100 days after vaccination. Moreover, the vaccine-induced T cellular response is oriented toward a TH1 response and no evidence of vaccine-enhanced disease have been reported. Discussion: BNT162b2 and mRNA-1273 can elicit specific antibodies titers and neutralizing antibodies concentrations above those observed among COVID-19 human convalescent serum in the first 100 days after vaccination. Data about vaccine efficacy in those with previous COVID-19 or immunocompromised is still limited.

Immune Checkpoint Inhibitors in People Living with HIV/AIDS: Facts and Controversies.

Immune checkpoint inhibitors (ICIs) are reshaping the landscape of cancer treatment, redefining the prognosis of several tumors. They act by restoring the cytotoxic activity of tumor-specific T lymphocytes that are in a condition of immune exhaustion. The same condition has been widely described in chronic HIV infection. In this review, we dissect the role of ICIs in people living with HIV/AIDS (PLWHIV). First, we provide an overview of the immunologic scenario. Second, we discuss the possible use of ICIs as adjuvant treatment of HIV to achieve elimination of the viral reservoir. Third, we examine the influence of HIV infection on ICI safety and effectiveness. Finally, we describe how the administration of ICIs impacts opportunistic infections.

The COVID-19 pandemic preparedness ... or lack thereof: from China to Italy.

COVID-19, that emerged in December 2019 in the city of Wuhan, China and is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly evolved into a pandemic. Italy has become one of the largest epicentres outside Asia, accounting now for at least 80,539 infections (cumulative incidence of 95.9/100,000) and 8,165 deaths (case fatality rate 10.1%). It has seriously affected people above the age of 60 years. The International Health Regulations (IHR) revised in 2005 bind governments to disclose vital information regarding the identification and detection of new disease outbreaks regardless of its causative agent. In contrast to the previous SARS epidemic, China timely informed the world about the onset of a new outbreak. It also soon disclosed the clinical characteristics of patients with COVID-19. Unfortunately, despite the fast recognition of the Chinese epidemic, the application of the 2005 IHR was not followed by an effective response in every country and most health authorities failed to rapidly perceive the threat posed by COVID-19. To further complicate matters, IHR implementation, which relies primarily on self-reporting data rather than on an external review mechanism, was limited in speed and further hindered by high costs. The response in Italy suffered from several limitations within the health system and services. The action against this threat must instead be quick, firm and at the highest trans-national level. The solution lies in further strengthening countries' preparedness through a clear political commitment, mobilization of proper resources and implementation of a strict surveillance and monitoring process.