In Vivo Treatment with Insulin-like Growth Factor 1 Reduces CCR5 Expression on Vaccine-Induced Activated CD4+ T-Cells.

At the heart of the DNA/ALVAC/gp120/alum vaccine's efficacy in the absence of neutralizing antibodies is a delicate balance of pro- and anti-inflammatory immune responses that effectively decreases the risk of SIVmac251 acquisition in macaques. Vaccine efficacy is linked to antibodies recognizing the V2 helical conformation, DC-10 tolerogenic dendritic cells eliciting the clearance of apoptotic cells via efferocytosis, and CCR5 downregulation on vaccine-induced gut homing CD4+ cells. RAS activation is also linked to vaccine efficacy, which prompted the testing of IGF-1, a potent inducer of RAS activation with vaccination. We found that IGF-1 changed the hierarchy of V1/V2 epitope recognition and decreased both ADCC specific for helical V2 and efferocytosis. Remarkably, IGF-1 also reduced the expression of CCR5 on vaccine-induced CD4+ gut-homing T-cells, compensating for its negative effect on ADCC and efferocytosis and resulting in equivalent vaccine efficacy (71% with IGF-1 and 69% without).

Automated detection of hospital outbreaks of multi-drug resistant pathogens in one Italian region.

BACKGROUND: Automated tools for antimicrobial resistance surveillance are critical for improving detection of drug-resistant organisms and informing prevention and control interventions. In this study, the WHONET-SaTScan software was used at a multihospital level in Tuscany, Italy, to identify case clusters consistent with hospital outbreaks caused by drug-resistant pathogens. METHODS: Antimicrobial resistance surveillance data from all Tuscany hospitals between January 2018 and December 2020 were analyzed using WHONET. The SaTScan package was used to detect case clusters applying a simulated prospective approach and the space-time permutation algorithm. Clusters were identified using resistance profiles and two distinct spatial variables: single medical services ('service') or groups of related services ('metaservice'). RESULTS: Data from eight bacterial pathogens were provided from 49 hospitals for 312,779 isolates from 158,809 patients. Single service-based analysis detected 693 hospital clusters, while metaservice-based analysis identified 635. There was no evidence for a difference between the two methods in terms of cluster length, cluster size, recurrence intervals, number of alerts, distribution across years or hospitals. Among clusters involving multiple services identified by both analyses, metaservice-detected clusters were usually larger and more statistically significant. CONCLUSIONS: WHONET-SaTScan proved to be a valuable multi-facility cluster detection tool that can be implemented for real-time surveillance.

WHO guidance development on medical devices in response to the COVID-19 pandemic.

Not available. The manuscript is an editorial communication.

Use of Intravenous Immunoglobulin Therapy at Unconventional Doses in Refractory Fulminant Systemic Lupus Erythematosus.

The use of human intravenous immunoglobulins (IVIg) in systemic lupus erythematosus (SLE) currently relies on evidence from small case series and is mainly regarded as an off-label strategy in cases that are refractory to conventional therapies or poorly controlled with high doses of corticosteroids. Standard dosage regimens typically entail the administration of a total amount of 2 g/kg of IVIg divided into five consecutive days in order to minimize the risk of severe adverse events. We herein describe the case of a 28-year-old woman with a known history of antiphospholipid syndrome (APS) who was admitted to our hospital following fulminant onset of SLE in spite of ongoing immunosuppressive therapy. Acute renal insufficiency with nephrotic-range proteinuria, central nervous system involvement, severe thrombocytopenia, malar rash, pancreatic injury and moderate-severe aortic valve steno-insufficiency were the most prominent clinical manifestations, along with high titres of anti-dsDNA antibodies. Pulses of methyl-prednisolone followed by high-dose corticosteroids proved ineffective. Strikingly, IVIg therapy delivered at unconventional doses (1.2 g/kg) due to the presence of multiple risk factors for adverse events resulted in a significant, comprehensive clinical improvement. Although large-scale randomized double-blind studies are needed, the use of IVIg might constitute a valuable therapeutic modality as a last-resort strategy in cases of fulminant SLE. The total dose of immunoglobulins should be dictated by the clinical response as well as the presence of pre-existing risk factors for adverse events. LEARNING POINTS: The use of immunoglobulins in the treatment of systemic lupus erythematosus is mainly based on small prospective studies and case series.Their use as a rescue strategy in cases of systemic lupus erythematosus that are refractory to conventional immunosuppressive therapy may be a valid therapeutic alternative in selected patients.The short-term clinical response and the presence of risk factors for adverse effects should dictate the overall dose of immunoglobulins administered to the patient.

Pancytopenia in a Patient with Rendu-Osler-Weber Syndrome and Uncommon Vascular Abnormalities.

Rendu-Osler-Weber syndrome, or hereditary hemorrhagic teleangiectasia (HHT), is a rare autosomal dominant vascular disorder, characterized by multiple mucocutaneous teleangiectases with recurrent nasal and gastrointestinal bleedings and/or solid-organ arteriovenous shunts. We describe the first case to our knowledge of pancytopenia in a 53-year-old patient, with a known history of HHT and recurrent nasal and gastrointestinal bleedings, who was found to have a major splenic artery aneurysm and other uncommon vascular abnormalities. In the absence of other evident causes of pancytopenia, hypersplenism was diagnosed. The patient underwent coil embolization of the splenic artery aneurysm, followed by rapid and sustained increase of white blood cell and platelet count. Splenic artery aneurysms are extremely uncommon in HHT as only anecdotal cases have been reported to date. However, we believe that the aneurysm critically contributed to the progression of splenomegaly and the development of pancytopenia.

Adjuvant-dependent innate and adaptive immune signatures of risk of SIVmac251 acquisition.

A recombinant vaccine containing Aventis Pasteur's canarypox vector (ALVAC)-HIV and gp120 alum decreased the risk of HIV acquisition in the RV144 vaccine trial. The substitution of alum with the more immunogenic MF59 adjuvant is under consideration for the next efficacy human trial. We found here that an ALVAC-simian immunodeficiency virus (SIV) and gp120 alum (ALVAC-SIV + gp120) equivalent vaccine, but not an ALVAC-SIV + gp120 MF59 vaccine, was efficacious in delaying the onset of SIVmac251 in rhesus macaques, despite the higher immunogenicity of the latter adjuvant. Vaccine efficacy was associated with alum-induced, but not with MF59-induced, envelope (Env)-dependent mucosal innate lymphoid cells (ILCs) that produce interleukin (IL)-17, as well as with mucosal IgG to the gp120 variable region 2 (V2) and the expression of 12 genes, ten of which are part of the RAS pathway. The association between RAS activation and vaccine efficacy was also observed in an independent efficacious SIV-vaccine approach. Whether RAS activation, mucosal ILCs and antibodies to V2 are also important hallmarks of HIV-vaccine efficacy in humans will require further studies.

Regulatory and Helper Follicular T Cells and Antibody Avidity to Simian Immunodeficiency Virus Glycoprotein 120.

T follicular regulatory cells (TFR) are a suppressive CD4(+) T cell subset that migrates to germinal centers (GC) during Ag presentation by upregulating the chemokine receptor CXCR5. In the GC, TFR control T follicular helper cell (TFH) expansion and modulate the development of high-affinity Ag-specific responses. In this study, we identified and characterized TFR as CXCR5(+)CCR7(-) "follicular" T regulatory cells in lymphoid tissues of healthy rhesus macaques, and we studied their dynamics throughout infection in a well-defined animal model of HIV pathogenesis. TFR were infected by SIVmac251 and had comparable levels of SIV DNA to CXCR5(-)CCR7(+) "T zone" T regulatory cells and TFH. Contrary to the SIV-associated TFH expansion in the chronic phase of infection, we observed an apparent reduction of TFR frequency in cell suspension, as well as a decrease of CD3(+)Foxp3(+) cells in the GC of intact lymph nodes. TFR frequency was inversely associated with the percentage of TFH and, interestingly, with the avidity of the Abs that recognize the SIV gp120 envelope protein. Our findings show changes in the TFH/TFR ratio during chronic infection and suggest possible mechanisms for the unchecked expansion of TFH cells in HIV/SIV infection.

Oligohydramnios in a pregnant Pakistani woman with Plasmodium vivax malaria.

In the Western world, the diagnosis and management of Plasmodium vivax malaria in pregnant women can be challenging, and the pathogenesis of adverse outcomes for both the mother and the foetus is still poorly known. The authors describe the case of a 29-year-old Pakistani woman at the 29th week of her second pregnancy, who was admitted to the Hospital following the abrupt onset of fever. At the time of admission, she had been living in Italy without travelling to any malaria-endemic areas for eight months. She was diagnosed with vivax malaria after a thin blood smear revealed the presence of plasmodial trophozoites and gametocytes and treated accordingly. Due to the onset of oligohydramnios, she underwent caesarian section at the 31st week of pregnancy with no further complications. Histological examination of the placenta showed no evidence of plasmodial infection, but was inconclusive. It is unclear whether oligohydramnios is a complication of pregnancy-related Plasmodium vivax malaria. Given the long latency of hypnozoites, every febrile pregnant patient with a previous stay in an endemic area should be screened for malaria with a thick and a thin blood smear.

TRIM5α does not affect simian immunodeficiency virus SIV(mac251) replication in vaccinated or unvaccinated Indian rhesus macaques following intrarectal challenge exposure.

TRIM5α is a natural resistance factor that binds retroviral capsid proteins and restricts virus replication. The B30.2/SPRY domain of TRIM5α is polymorphic in rhesus macaques, and some alleles are associated with reduced simian immunodeficiency virus (SIV) SIV(mac251) and SIV(smE543) replication in vivo. We determined the distribution of TRIM5α alleles by PCR and sequence analysis of the B30.2/SPRY domain in a cohort of 82 macaques. Thirty-nine of these macaques were mock vaccinated, 43 were vaccinated with either DNA-SIV/ALVAC-SIV/gp120, ALVAC-SIV/gp120, or gp120 alone, and all were exposed intrarectally to SIV(mac251) at one of three doses. We assessed whether the TRIM5α genotype of the macaques affected the replication of challenge virus by studying the number of SIV variants transmitted, the number of exposures required, the SIV(mac251) viral level in plasma and tissue, and the CD4(+) T-cell counts. Our results demonstrated that TRIM5α alleles, previously identified as restrictive for SIV(mac251) replication in vivo following intravenous exposure, did not affect SIV(mac251) replication following mucosal exposure, regardless of prior vaccination, challenge dose, or the presence of the protective major histocompatibility complex alleles (MamuA01(+), MamuB08(+), or MamuB017(+)). The TRIM5α genotype had no apparent effect on the number of transmitted variants or the number of challenge exposures necessary to infect the animals. DNA sequencing of the SIV(mac251) Gag gene of the two stocks used in our study revealed SIV(mac239)-like sequences that are predicted to be resistant to TRIM5α restriction. Thus, the TRIM5α genotype does not confound results of mucosal infection of rhesus macaques with SIV(mac251).