Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is the novel pathogen responsible for the coronavirus disease 19 (COVID-19) outbreak. Researchers and clinicians are exploring the ...pathogenetic mechanisms of the viral-induced damage and growing interest is focusing on the short-term and long-term immune-mediated consequences triggered by the infection. We will focus on post-SARS-CoV2 infection arthritis which may arise as a new pathological condition associated with COVID-19. In this article, we describe a case of acute oligoarthritis occurring 13 days after a SARS-CoV2 severe pneumonia in a middle-aged Caucasian man and we go over a brief review of the current available literature. We hypothesize that molecular mimicry might be the basic immunological mechanism responsible for the onset of COVID-19-related arthritis based on the current knowledge of SARS-CoV2 and on the known pathogenetic mechanism of viral-induced arthritis.
HIV-1 broadly neutralizing antibodies (bNAbs) are being explored as passively administered therapeutic and preventative agents. However, the extensively diversified HIV-1 envelope glycoproteins (Env) ...rapidly acquire mutations to evade individual bNAbs in monotherapy regimens. The use of a "single" agent to simultaneously target distinct Env epitopes is desirable to overcome viral diversity. Here, we report the use of tandem single-chain variable fragment (ScFv) domains of two bNAbs, specific for the CD4-binding site and V3 glycan patch, to form anti-HIV-1 bispecific ScFvs (Bi-ScFvs). The optimal Bi-ScFv crosslinks adjacent protomers within one HIV-1 Env spike and has greater neutralization breadth than its parental bNAbs. Furthermore, the combination of this Bi-ScFv with a third bNAb recognizing the Env membrane proximal external region (MPER) results in a trispecific bNAb, which has nearly pan-isolate neutralization breadth and high potency. Thus, multispecific antibodies combining functional moieties of bNAbs could achieve outstanding neutralization capacity with augmented avidity.
The recent outbreak of coronavirus disease (COVID 19), spreading from China all around the world in early 2020, has led scientists to investigate the immuno-mediated mechanisms underlying the Severe ...Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) infection. Depending on the amount of cytokines released as the result of the immunological activation induced by SARS-CoV2, three major clinical phenotypes can be identified: “mild”,symbolized as a “drizzle” of cytokines, severe as a “storm”, and critical as a “hurricane”. In patients with mild symptoms, the release of pro-inflammatory cytokines is balanced to obtain a defense response against the virus which is often self-limiting and overcomes without tissue damage. In severe phenotype, resembling a “cytokine-release syndrome”, SARS-CoV2 causes the lysis of the immune-mediators leading to a cytokine storm able to induce lung epithelium damage and acute respiratory distress syndrome. In critical patients, the immune response may become uncontrolled, thus the cytokine burst resembles a form of secondary hemophagocytic lymphohistiocytosis which may result in a multi organ failure. In addition to the standard of care, an immune-modulatory therapy tailored to each one of the different phenotypes should be used in order to prevent or reduce the release of cytokines responsible for organ damage and disease progression.
ObjectivesDevelop recommendations for women's health issues and family planning in systemic lupus erythematosus (SLE) and/or antiphospholipid syndrome (APS).MethodsSystematic review of evidence ...followed by modified Delphi method to compile questions, elicit expert opinions and reach consensus.ResultsFamily planning should be discussed as early as possible after diagnosis. Most women can have successful pregnancies and measures can be taken to reduce the risks of adverse maternal or fetal outcomes. Risk stratification includes disease activity, autoantibody profile, previous vascular and pregnancy morbidity, hypertension and the use of drugs (emphasis on benefits from hydroxychloroquine and antiplatelets/anticoagulants). Hormonal contraception and menopause replacement therapy can be used in patients with stable/inactive disease and low risk of thrombosis. Fertility preservation with gonadotropin-releasing hormone analogues should be considered prior to the use of alkylating agents. Assisted reproduction techniques can be safely used in patients with stable/inactive disease; patients with positive antiphospholipid antibodies/APS should receive anticoagulation and/or low-dose aspirin. Assessment of disease activity, renal function and serological markers is important for diagnosing disease flares and monitoring for obstetrical adverse outcomes. Fetal monitoring includes Doppler ultrasonography and fetal biometry, particularly in the third trimester, to screen for placental insufficiency and small for gestational age fetuses. Screening for gynaecological malignancies is similar to the general population, with increased vigilance for cervical premalignant lesions if exposed to immunosuppressive drugs. Human papillomavirus immunisation can be used in women with stable/inactive disease.ConclusionsRecommendations for women's health issues in SLE and/or APS were developed using an evidence-based approach followed by expert consensus.
In spite of the fact that the diagnosis of haemophilia is essentially clinical and laboratory‐based, imaging has become an important tool for the evaluation of complications, diagnostic confirmation ...and/or complementation and therapeutic follow‐up in haemophilic arthropathy. Radiography remains the workforce horse in the diagnosis and follow‐up of haemophilic arthropathy. The radiographical findings in arthropathy follow an expected sequence of events and are overall similar in different joints. Magnetic resonance imaging (MRI) has advantages over radiography based on its capability of visualizing soft tissue and cartilage changes in haemophilic joints. The recent development and standardization of MRI scoring systems for measuring soft tissue and cartilage abnormalities may enable the comparison of pathological joint findings in clinical trials conducted at different institutions across the world. The implementation of high‐frequency transducers and colour/power Doppler capabilities has provided new insights for clinical applications of ultrasonography (US) in haemophilic arthropathy. In spite of the imaging modality's technical challenges such as operator‐dependency, US has advantages over MRI. One of these advantages is its ability of differentiating synovium hypertrophy and hemosiderin deposition, which is not possible with MRI given the presence of susceptibility artefacts from extracellular hemosiderin on gradient‐echo MR images. In addition to the aforementioned conventional imaging modalities, novel imaging techniques (blood oxygen level dependent, ultrasmall superparamagnetic iron‐oxide contrast‐enhanced, and T1 and T2 mapping MRI, ultrasound biomicroscopy, microbubble contrast‐enhanced US and positron emission tomography, among others) hold promise for early assessment of haemophilic arthropathy in the future upon completion of their clinical validation.
Characterization of human monoclonal antibodies is providing considerable insight into mechanisms of broad HIV-1 neutralization. Here we report an HIV-1 gp41 membrane-proximal external region ...(MPER)-specific antibody, named 10E8, which neutralizes ∼98% of tested viruses. An analysis of sera from 78 healthy HIV-1-infected donors demonstrated that 27% contained MPER-specific antibodies and 8% contained 10E8-like specificities. In contrast to other neutralizing MPER antibodies, 10E8 did not bind phospholipids, was not autoreactive, and bound cell-surface envelope. The structure of 10E8 in complex with the complete MPER revealed a site of vulnerability comprising a narrow stretch of highly conserved gp41-hydrophobic residues and a critical arginine or lysine just before the transmembrane region. Analysis of resistant HIV-1 variants confirmed the importance of these residues for neutralization. The highly conserved MPER is a target of potent, non-self-reactive neutralizing antibodies, suggesting that HIV-1 vaccines should aim to induce antibodies to this region of HIV-1 envelope glycoprotein.
Objectives To develop recommendations for the diagnosis, prevention and treatment of neuropsychiatric systemic lupus erythematosus (NPSLE) manifestations. Methods The authors compiled questions on ...prevalence and risk factors, diagnosis and monitoring, therapy and prognosis of NPSLE. A systematic literature search was performed and evidence was categorised based on sample size and study design. Results Systemic lupus erythematosus (SLE) patients are at increased risk of several neuropsychiatric manifestations. Common (cumulative incidence >5%) manifestations include cerebrovascular disease (CVD) and seizures; relatively uncommon (1–5%) are severe cognitive dysfunction, major depression, acute confusional state (ACS), peripheral nervous disorders psychosis. Strong risk factors (at least fivefold increased risk) are previous or concurrent severe NPSLE (for cognitive dysfunction, seizures) and antiphospholipid antibodies (for CVD, seizures, chorea). The diagnostic work-up of suspected NPSLE is comparable to that in patients without SLE who present with the same manifestations, and aims to exclude causes unrelated to SLE. Investigations include cerebrospinal fluid analysis (to exclude central nervous system infection), EEG (to diagnose seizure disorder), neuropsychological tests (to assess cognitive dysfunction), nerve conduction studies (for peripheral neuropathy) and MRI (T1/T2, fluid-attenuating inversion recovery, diffusion-weighted imaging, enhanced T1 sequence). Glucocorticoids and immunosuppressive therapy are indicated when NPSLE is thought to reflect an inflammatory process (optic neuritis, transverse myelitis, peripheral neuropathy, refractory seizures, psychosis, ACS) and in the presence of generalised lupus activity. Antiplatelet/anticoagulation therapy is indicated when manifestations are related to antiphospholipid antibodies, particularly thrombotic CVD. Conclusions Neuropsychiatric manifestations in SLE patients should be first evaluated and treated as in patients without SLE, and secondarily attributed to SLE and treated accordingly.
Abstract As soon as autoinflammatory diseases (AIDs) emerged as new entities, they have been linked to the well known world of autoimmunity. In fact, AIDs and systemic autoimmune diseases (ADs), ...share some characteristics: they start with the prefix “auto” to define a pathological process directed against self; they are systemic diseases, frequently involving musculoskeletal system; both include monogenic and polygenic diseases. From the pathogenetic point of view, they are characterized by a chronic activation of immune system, which eventually leads to tissue inflammation in genetically predisposed individuals. Nevertheless, the specific effectors of the damage are different in the two groups of diseases: in AIDs the innate immune system directly causes tissue inflammation, whereas in ADs the innate immune system activates the adaptive immune system which, in turn, is responsible for the inflammatory process. Mutations in inflammasome-related proteins, particularly in NOD-like receptor (NLR) genes, have been strongly associated to the occurrence of AIDs, whereas the link between inflammasome and ADs is less clear. However, a role for this multiprotein-complex in some ADs can be postulated, since a wide spectrum of endogenous danger signals can activate NLRs and inflammasome products, including IL-1ß, can activate adaptive immunity. An association between single nucleotide polymorphisms (SNPs) localized in the inflammasome gene NLRP1 and systemic lupus erythematosus has recently been reported. AIDs and ADs are currently subdivided into two different groups, but looking at their similarities they might be considered as a single group of diseases with a large immune pathological and clinical spectrum which includes at one end pure ADs and at the other end pure AIDs.
Broadly neutralizing antibodies (bNAbs) against HIV-1 envelope (Env) inform vaccine design and are potential therapeutic agents. We identified SF12 and related bNAbs with up to 62% neutralization ...breadth from an HIV-infected donor. SF12 recognized a glycan-dominated epitope on Env’s silent face and was potent against clade AE viruses, which are poorly covered by V3-glycan bNAbs. A 3.3Å cryo-EM structure of a SF12-Env trimer complex showed additional contacts to Env protein residues by SF12 compared with VRC-PG05, the only other known donor-derived silentface antibody, explaining SF12's increased neutralization breadth, potency, and resistance to Env mutation routes. Asymmetric binding of SF12 was associated with distinct N-glycan conformations across Env protomers, demonstrating intra-Env glycan heterogeneity. Administrating SF12 to HIV-1-infected humanized mice suppressed viremia and selected for viruses lacking the N448gp120 glycan. Effective bNAbs can therefore be raised against HIV-1 Env’s silent face, suggesting their potential for HIV-1 prevention, therapy, and vaccine development.
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•Silentface (SF) bNAbs can reach substantial neutralization breadth and potency•Defined structure of a SF bNAb bound to an Env trimer•Binding of SF bNAb resulted in trimer asymmetry in the V3 region•SF antibodies have in vivo activity and potential for clinical use
VRC-PG05 was the only donor-derived antibody against the silentface (SF) of HIV-1 envelope described to date. Schoofs et al. identify the antibody SF12 and its relatives, which recognize the center of the SF with a different angle and more extensive protein recognition than VRC-PG05, thereby achieving substantial neutralizing ability and potential for clinical use.
Background/objectives: Tailored primary prophylaxis (TPP) is a reduced‐intensity treatment program for hemophiliacs with the goal of preventing arthropathy. Our primary aim was to evaluate the joint ...outcomes of treated subjects using magnetic resonance imaging (MRI) and physical examination as outcome measures. Methods: Ankles, elbows and knees (index joints) of 24 subjects (median range age at start of therapy, 1.6 1–2.5 years) with severe hemophilia A enrolled in the Canadian Hemophilia Primary Prophylaxis Study (CHPS) were examined by MRI at a median age of 8.8 years (range 6.2–11.5 years). Subjects were treated with TPP using a recombinant factor VIII concentrate, starting once weekly and escalating in frequency and dose according to frequency of bleeding. Results: Osteochondral changes (cartilage loss/subchondral bone damage) were detected in 9% (13/140) of the index joints and 50% (12/24) of study subjects. Osteochondral changes were restricted to joints with a history of clinically reported joint bleeding. Soft tissue changes were detected in 31% (20/65) of index joints with no history of clinically reported bleeding (ankles 75% (12/16); elbows 19% (6/32); and knees 12% (2/17)). In these apparently ‘bleed free’ index joints hemosiderin deposition was detected by MRI in 26% (17/65) of joints (ankles 63% (10/16); elbows 16% (5/32), and knees 12% (2/17)). Conclusion: TPP did not completely avoid the development of MRI‐detected structural joint changes in hemophilic boys in this prospective study. A longer period of follow‐up is required for assessment of the longitudinal course of these early changes in hemophilic arthropathy, detected using a sensitive imaging technique (MRI).
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