Membrane Proteome-Wide Screening of Autoantibodies in CIDP Using Human Cell Microarray Technology.

BACKGROUND AND OBJECTIVES: Autoantibody discovery in complex autoimmune diseases is challenging. Diverse successful antigen identification strategies are available, but, so far, have often been unsuccessful, especially in the discovery of protein antigens in which conformational and post-translational modification are critical. Our study assesses the utility of a human membrane and secreted protein microarray technology to detect autoantibodies in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). METHODS: A cell microarray consisting of human embryonic kidney-293 cells expressing >5,000 human proteins was used. First, a validation step was performed with 4 serum samples from patients with autoimmune nodopathy (AN) to assess the ability of this technology to detect circulating known autoantibodies. The ability of the cell microarray technology to discover novel IgG autoantibodies was assessed incubating the array with 8 CIDP serum samples. Identified autoantibodies were subsequently validated using cell-based assays (CBAs), ELISA, and/or tissue immunohistochemistry and analyzed in a cohort of CIDP and AN (n = 96) and control (n = 100) samples. RESULTS: Serum anti-contactin-1 and anti-neurofascin-155 were detected by the human cell microarray technology. Nine potentially relevant antigens were found in patients with CIDP without other detectable antibodies; confirmation was possible in six of them: ephrin type-A receptor 7 (EPHA7); potassium-transporting ATPase alpha chain 1 and subunit beta (ATP4A/4B); leukemia-inhibitory factor (LIF); and interferon lambda 1, 2, and 3 (IFNL1, IFNL2, IFNL3). Anti-ATP4A/4B and anti-EPHA7 antibodies were detected in patients and controls and considered unrelated to CIDP. Both anti-LIF and anti-IFNL antibodies were found in the same 2 patients and were not detected in any control. Both patients showed the same staining pattern against myelinating fibers of peripheral nerve tissue and of myelinating neuron-Schwann cell cocultures. Clinically relevant correlations could not be established for anti-LIF and anti-IFNL3 antibodies. DISCUSSION: Our work demonstrates the utility of human cell microarray technology to detect known and discover unknown autoantibodies in human serum samples. Despite potential CIDP-associated autoantibodies (anti-LIF and anti-IFNL3) being identified, their clinical and pathogenic relevance needs to be elucidated in bigger cohorts.

Excellent response to anti-CD38 therapy with daratumumab in a patient with severe refractory CANOMAD.

BACKGROUND: Intravenous immunoglobulin (IVIG) and rituximab are considered the first-line and second-line treatments for Chronic Ataxic Neuropathy and Ophthalmoplegia with IgM-paraprotein, cold Agglutinins, and anti-Disialosyl antibodies (CANOMAD), with an overall clinical response around 50%. New anti-CD38 daratumumab, targeting long-lived plasma cells, has been reported as a promising therapy for treatment-refractory antibody-mediated disorders. We report the first case of a severe refractory CANOMAD, successfully treated with daratumumab. METHODS: A patient in their 70s with severe relapsing CANOMAD, refractory to IVIG, steroids, rituximab and ibrutinib developed severe tetraparesis and respiratory failure. Plasma exchange (PE) improved motor and ventilatory function; however, after 6 weeks, patient remained PE dependent. Intravenous daratumumab was initiated at 16 mg/kg weekly for 3 weeks, every 2 weeks for the second and third month, and monthly afterwards. RESULTS: After 3 weeks of starting daratumumab, PE was discontinued and, since then, the patient evolved to complete recovery. Antidisialosyl antibody titres decreased after PE and remained stable during daratumumab. Serum neurofilament light-chain levels were elevated in the exacerbation phase and normalised after daratumumab. The patient remains in clinical remission under monthly daratumumab, 12 months after initiation. CONCLUSIONS: The first patient with aggressive treatment-refractory CANOMAD treated with daratumumab provides proof-of-principle evidence that daratumumab may be an effective treatment in IgM-related neuropathies.

Clinicopathological correlates in frontotemporal lobar degeneration: motor neuron disease spectrum.

Amyotrophic lateral sclerosis (ALS) is a devastating motor neuron disease (MND) that shares a common clinical, genetic and pathologic spectrum with frontotemporal dementia (FTD). It is highly heterogeneous in its presentation and features. Up to 50% of patients with MND develop cognitive-behavioural symptoms during the course of the disease, meeting criteria for FTD in 10-15% of cases. In the absence of a precise biomarker, neuropathology is still a valuable tool to understand disease nosology, reach a definite diagnostic confirmation and help define specific subgroups of patients with common phenotypic, genetic and biomarker profiles. However, few neuropathological series have been published, and the frequency of FTLD in MND is difficult to estimate. In this work we describe a large clinicopathologic series of MND, analysing the frequency of concurrent FTLD changes and trying to define specific subgroups of patients based on their clinical, genetic and pathological characteristics. We performed an observational, retrospective, multi-centre case study. We included all cases meeting neuropathological criteria for MND from the Neurological Tissue Bank of the FRCB-IDIBAPS-Hospital Clínic Barcelona Biobank between 1994 and 2022, regardless of their last clinical diagnosis. While brain donation is encouraged in all patients, it is performed in very few, and representativeness of the cohort might not be precise for all patients with MND. We retrospectively reviewed clinical and neuropathological data, and describe the main clinical, genetic and pathogenic features, comparing neuropathologic groups between MND with and without FTLD changes and aiming to define specific subgroups. We included brain samples from 124 patients, 44 of whom (35.5%) had FTLD neuropathologic features (i.e. FTLD-MND). Pathologic TDP-43 aggregates were present in 93.6% of the cohort and were more extensive (higher Brettschneider stage) in those with concurrent FTLD (p < 0.001). Motor symptom onset was more frequent in the bulbar region in FTLD-MND cases than in those with isolated MND (p = 0.023), with no differences in survival. We observed a better clinicopathological correlation in the MND group than in the FTLD-MND group (93.8% vs 61.4%; p < 0.001). Pathogenic genetic variants were more common in the FTLD-MND group, especially C9orf72. We describe a frequency of FTLD of 35.5% in our series of neuropathologically confirmed cases of MND. The FTLD-MND spectrum is highly heterogeneous in all aspects, especially in patients with FTLD, in whom it is particularly difficult to define specific subgroups. In the absence of definite biomarkers, neuropathology remains a valuable tool for a definite diagnosis, increasing our knowledge in disease nosology.

Clinical Classification of Variants in the Valosin-Containing Protein Gene Associated With Multisystem Proteinopathy.

Background and Objectives: Pathogenic variants in the valosin-containing protein (VCP) gene cause a phenotypically heterogeneous disorder that includes myopathy, motor neuron disease, Paget disease of the bone, frontotemporal dementia, and parkinsonism termed multisystem proteinopathy. This hallmark pleiotropy makes the classification of novel VCP variants challenging. This retrospective study describes and assesses the effect of 19 novel or nonpreviously clinically characterized VCP variants identified in 28 patients (26 unrelated families) in the retrospective VCP International Multicenter Study. Methods: A 6-item clinical score was developed to evaluate the phenotypic level of evidence to support the pathogenicity of the novel variants. Each item is allocated a value, a score ranging from 0.5 to 5.5 points. A receiver-operating characteristic curve was used to identify a cutoff value of 3 to consider a variant as high likelihood disease associated. The scoring system results were confronted with results of in vitro ATPase activity assays and with in silico analysis. Results: All variants were missense, except for one small deletion-insertion, 18 led to amino acid changes within the N and D1 domains, and 13 increased the enzymatic activity. The clinical score coincided with the functional studies in 17 of 19 variants and with the in silico analysis in 12 of 19. For 12 variants, the 3 predictive tools agreed, and for 7 variants, the predictive tools disagreed. The pooled data supported the pathogenicity of 13 of 19 novel VCP variants identified in the study. Discussion: This study provides data to support pathogenicity of 14 of 19 novel VCP variants and provides guidance for clinicians in the evaluation of novel variants in the VCP gene.

Immunogenicity and safety assessment of a SARS-CoV-2 recombinant spike RBD protein vaccine (Abdala) in paediatric ages 3-18 years old: a double-blinded, multicentre, randomised, phase 1/2 clinical trial (ISMAELILLO study).

Background: COVID-19 in paediatric ages could result in hospitalizations and death. In addition, excluding children from vaccination could turn them into reservoirs of the SARS-COV-2. Safe and effective COVID-19 vaccines are urgently needed for large-scale paediatric vaccination. ISMAELILLO study aimed to evaluate safety and immunogenicity of two strengths of a new recombinant receptor-binding domain (RBD) protein vaccine (Abdala) in paediatric population. Methods: A double-blinded, multicentre, randomised, phase 1/2 clinical trial was conducted in nine polyclinics in the province of Camagüey, Cuba. Healthy children and adolescents were stratified according to age (3-11 years old, or 12-18 years old) and they were randomly assigned (1:1; block size four) in two dosage level groups of vaccine to receive three intramuscular doses of 25 µg or 50 µg of RBD, 14 days apart. Main safety endpoint was analyzed as the percentage of serious adverse reactions during vaccination up to 28 days after the third dose (Day 56) in participants who received at least one dose vaccination. The primary immunogenicity endpoint assessed was seroconversion rate of anti-RBD IgG antibody at day 56. The immunogenicity outcomes were assessed in the per-protocol population. This trial is registered with Cuban Public Registry of Clinical Trials, RPCEC00000381. Findings: Between July 15, 2021, and August 16, 2021, 644 paediatric subjects were screened, of whom 592 were enrolled after verifying that they met the selection criteria: firstly 88 were included in Phase 1 of the study and 504 who completed Phase 2. The vaccine was well tolerated. Injection site pain was the most frequently reported local event (143 [8·4%] of 1707 total doses applied), taking place in 66/851 (7·8%) in the 25 µg group and in 77/856 (9·0%) in the 50 µg. The most common systemic adverse event (AE) was headache: 23/851 (2·7%) in the 25 µg group and 19/856 (2·2%) in the 50 µg. Reactogenicity was mild or moderate in severity, represented in 75% of cases by local symptoms, completely resolved in the first 24-48 h. Twenty-eight days after the third dose, seroconversion anti-RBD IgG were observed in 98·2% of the children and adolescents (231/234) for the 50 µg group and 98·7% (224/228) for the 25 µg group without differences between both strength. The specific IgG antibody geometric mean titres (GMT) showed higher titres between participants who received Abdala 50 µg (231·3; 95% CI 222·6-240·4) compared to those who received 25 µg (126·7; 95% CI 121·9-131·7). The mean ACE2 inhibition %, were 59·4% for 25 µg, and for 50 µg, 72·9% (p < 0·01). Both strength elicited neutralising activity against the SARS-CoV-2, specifically (18·3; 95% CI 14·7-22·78) for Abdala 25 µg and (36·4; 95% CI 30·26-43·8) for 50 µg to the selected sample analyzed. Interpretation: Abdala vaccine was safe and well tolerated at both antigenic strength levels tested in participants aged between 3 and 18 years. Regarding immunogenicity, Abdala Vaccine stimulated the production of specific IgG antibodies against the RBD of SARS-CoV-2 as well as the production of ACE2 inhibition titres and neutralising antibodies (Nab) in children and adolescents. Funding: Centre for Genetic Engineering and Biotechnology (CIGB), Havana, Cuba.

Endogenous Biological Drivers in Diabetic Lower Limb Wounds Recurrence: Hypothetical Reflections.

An impaired healing response underlies diabetic foot wound chronicity, frequently translating to amputation, disability, and mortality. Diabetics suffer from underappreciated episodes of post-epithelization ulcer recurrence. Recurrence epidemiological data are alarmingly high, so the ulcer is considered in "remission" and not healed from the time it remains epithelialized. Recurrence may result from the combined effects of behavioral and endogenous biological factors. Although the damaging role of behavioral, clinical predisposing factors is undebatable, it still remains elusive in the identification of endogenous biological culprits that may prime the residual scar tissue for recurrence. Furthermore, the event of ulcer recurrence still waits for the identification of a molecular predictor. We propose that ulcer recurrence is deeply impinged by chronic hyperglycemia and its downstream biological effectors, which originate epigenetic drivers that enforce abnormal pathologic phenotypes to dermal fibroblasts and keratinocytes as memory cells. Hyperglycemia-derived cytotoxic reactants accumulate and modify dermal proteins, reduce scar tissue mechanical tolerance, and disrupt fibroblast-secretory activity. Accordingly, the combination of epigenetic and local and systemic cytotoxic signalers induce the onset of "at-risk phenotypes" such as premature skin cell aging, dysmetabolism, inflammatory, pro-degradative, and oxidative programs that may ultimately converge to scar cell demise. Post-epithelialization recurrence rate data are missing in clinical studies of reputed ulcer healing therapies during follow-up periods. Intra-ulcer infiltration of epidermal growth factor exhibits the most consistent remission data with the lowest recurrences during 12-month follow-up. Recurrence data should be regarded as a valuable clinical endpoint during the investigational period for each emergent healing candidate.

A phase 3, randomised, double-blind, placebo-controlled clinical trial evaluation of the efficacy and safety of a SARS-CoV-2 recombinant spike RBD protein vaccine in adults (ABDALA-3 study).

Background: The pandemic of COVID-19 raised the urgent need for safe and efficacious vaccines against SARS-CoV-2. We evaluated the efficacy and safety of a new SARS-CoV-2 virus receptor-binding domain (RBD) vaccine. Methods: A phase 3, multicentre, randomised, double-blind, placebo-controlled trial was carried out at 18 clinical sites in three provinces of the south-eastern region of Cuba. Subjects (healthy or those with controlled chronic diseases) aged between 19 and 80 years, who gave written informed consent were eligible. Subjects were randomly assigned (1:1, in blocks) to two groups: placebo, and 50 µg RBD vaccine (Abdala). The product was administered intramuscularly, 0.5 mL in the deltoid region, in a three-dose immunization schedule at 0-14-28 days. The organoleptic characteristics and presentations of the vaccine and placebo were identical. All participants (subjects, clinical researchers, statisticians, laboratory technicians, and monitors) remained blinded during the study period. The main endpoint was to evaluate the efficacy of the Abdala vaccine in the prevention of symptomatic COVID-19. The trial is registered with the Cuban Public Registry of Clinical Trials, RPCEC00000359. Findings: Between March 22 to April 03, 2021, 48,290 subjects were included (24,144 and 24,146 in the placebo and Abdala groups, respectively) in the context of predominant D614G variant circulation. The evaluation of the main efficacy outcomes occurred during May-June 2021, starting at May 3rd, in the context of high circulation of mutant viruses, predominantly VOC Beta. The incidence of adverse reactions for individuals in the placebo and Abdala vaccine groups were 1227/24,144 (5.1%) and 1621/24,146 (6.7%), respectively. Adverse reactions were mostly mild, and from the injection site, which resolved in the first 24-48 h. No severe adverse events with demonstrated cause-effect relationship attributable to the vaccine were reported. Symptomatic COVID-19 disease was confirmed in 142 participants in the placebo group (78.44 incidence per 1000 person-years, 95% confidence interval [CI], 66.07-92.46) and in 11 participants in Abdala vaccine group (6.05 incidence per 1000 person years; 95% CI 3.02-10.82). The Abdala vaccine efficacy against symptomatic COVID-19 was 92.28% (95% CI 85.74-95.82). Moderate/serious forms of COVID-19 occurred in 30 participants (28 in the placebo group and only 2 in the Abdala vaccine group) for a vaccine efficacy of 92.88% (95% CI 70.12-98.31). There were five critical patients (of which four died), all in the placebo group. Interpretation: The Abdala vaccine was safe, well tolerated, and highly effective, fulfilling the WHO target product profile for COVID-19 vaccines. Those results, along with its immunization schedule and the advantage of easy storage and handling conditions at 2-8 °C, make this vaccine an option for the use in immunization strategies as a key tool for the control of the pandemic. Funding: Centre for Genetic Engineering and Biotechnology (CIGB), Havana, Cuba.

Antibodies against the flotillin-1/2 complex in patients with multiple sclerosis.

Multiple sclerosis is a tissue-specific autoimmune disease of the central nervous system in which the antigen(s) remains elusive. Antibodies targeting the flotillin-1/2 complex have been described in 1-2% of the patients in a recent study. Other candidate antigens as anoctamin-2 or neurofascin-155 have been previously described in multiple sclerosis patients, although their clinical relevance remains uncertain. Our study aims to analyse the frequency and clinical relevance of antibodies against neurofascin-155, anoctamin-2 and flotillin-1/2 complex in multiple sclerosis. Serum (n = 252) and CSF (n = 50) samples from 282 multiple sclerosis patients were included in the study. The control group was composed of 260 serum samples (71 healthy donors and 189 with other neuroinflammatory disorders). Anti-flotillin-1/2, anti-anoctamin-2 and anti-neurofascin-155 antibodies were tested by cell-based assays using transfected cells. We identified six multiple sclerosis patients with antibodies against the flotillin-1/2 complex (2.1%) and one multiple sclerosis patient with antibodies against anoctamin-2 (0.35%). All multiple sclerosis patients were negative for anti-neurofascin-155 antibodies. Three of the anti-flotillin-1/2 positive patients showed anti-flotillin-1/2 positivity in other serum samples extracted at different moments of their disease. Immunoglobulin G subclasses of anti-flotillin-1/2 antibodies were predominantly one and three. We confirm that antibodies targeting the flotillin-1/2 complex are present in a subgroup of patients with multiple sclerosis. Further studies are needed to understand the clinical and pathological relevance of anti-flotillin-1/2 autoantibodies in multiple sclerosis.

A new homozygous missense variant in LMOD3 gene causing mild nemaline myopathy with prominent facial weakness.

Nemaline myopathy (NEM) type 10, caused by biallelic mutations in LMOD3, is a severe congenital myopathy clinically characterized by generalized hypotonia and muscle weakness, respiratory insufficiency, joint contractures, and bulbar weakness. Here, we describe a family with two adult patients presenting mild nemaline myopathy due to a novel homozygous missense variant in LMOD3. Both patients presented mild delayed motor milestones, frequent falls during infancy, prominent facial weakness and mild muscle weakness in the four limbs. Muscle biopsy showed mild myopathic changes and small nemaline bodies in a few fibers. A neuromuscular gene panel revealed a homozygous missense variant in LMOD3 that co-segregated with the disease in the family (NM_198271.4: c.1030C>T; p.Arg344Trp). The patients described here provide evidence of the phenotype-genotype correlation, suggesting that non-truncating variants in LMOD3 lead to milder phenotypes of NEM type 10.

Isolation and characterization of new bacteriophages active against Clostridium tyrobutyricum and their role in preventing the late blowing defect of cheese.

Lytic bacteriophages (phages) offer a great potential as biocontrol agents for spoilage Clostridium tyrobutyricum, responsible for butyric acid fermentation in semi-hard and hard ripened cheeses, resulting in late gas blowing defect. With this aim, we have isolated, identified and characterized new lytic phages of C. tyrobutyricum, and have evaluated their efficacy to control cheese late blowing by adding them to manufacture milk. Silage, soil, milk and cheese from dairy farms were screened for anti-clostridial phages, obtaining 96 isolates active against C. tyrobutyricum. According to host range, source and plaque morphology, we obtained 20 phage profiles, 8 of them (represented by phages FA3, FA21, FA29, FA52, FA58, FA67, FA70 and FA88) showing a wider host range and high quality lysis, which were further characterized. Selected isolates showed a non-contractile tail, belonging to the Siphoviridae family, and were grouped into 3 restriction profiles. Viable phages were detected after storage in sodium-magnesium buffer (SM buffer), skim milk and acidified skim milk (pH 5) for 7 d at 4 °C, 12 °C and 37 °C, although a decline in infectivity was observed in some cases. Good phage survival was also detected during semi-hard cheese manufacture and ripening (60 d), and cheese lactococci counts, pH, dry matter values, and volatile compounds were not affected by phage addition. In semi-hard cheese, phage FA67 impaired the early germination of C. tyrobutyricum spores and caused a significant decrease in clostridial vegetative cells counts at 14 d of ripening, delaying by 2 weeks the consumption of lactic acid, formation of butyric acid and appearance of late blowing symptoms, compared to the spoilt control cheese without the phage. This is the first report on the application of phage to control C. tyrobutyricum in cheese.

Correction to "Cuban Abdala vaccine: Effectiveness in preventing severe disease and death from COVID-19 in Havana, Cuba; A cohort study" [The Lancet Regional Health - Americas 2022; 16: 100366] https://doi.org/10.1016/j.lana.2022.100366.

[This corrects the article DOI: 10.1016/j.lana.2022.100366.].

Leptospirosis-induced acute acquired inflammatory neuropathy.

Leptospirosis is a zoonotic infection that can present with neurological manifestations. Although uncommon, it may affect the peripheral nervous system in the form of polyradiculoneuropathy. We report the case of a 30-year-old male who developed flaccid tetraparesis and multiple cranial neuropathies on the fourteenth day of admission to the intensive care unit for fever and multi-organ failure. We also review the existing literature about peripheral nerve damage in leptospirosis and present our hypothesis on the possible pathogenic mechanisms. Electrophysiological findings were consistent with acute demyelinating polyradiculoneuropathy and extensive blood tests were positive for leptospiral IgM and IgG antibodies. Treatment with plasmapheresis was begun, followed by intravenous immunoglobulin (IVIg), and the patient improved slowly. Our work adds to the evidence of leptospirosis infection as a cause of acute demyelinating polyneuropathy. The possibility that leptospirosis-polyradiculoneuropathy may be caused by an immune pathogenesis emphasizes the importance of identifying this entity because immunomodulatory therapy could play a vital role in the recovery process.

Inhibitory activity of aromatic plant extracts against dairy-related Clostridium species and their use to prevent the late blowing defect of cheese.

The aim of the present work was the selection of aromatic plant essential oils (EOs) and/or ethanolic extracts (EEs) to prevent the late blowing defect (LBD) of cheese caused by Clostridium spp. EEs resulted more effective than EOs to inhibit dairy-borne Clostridium spp. in vitro. Savory, hyssop, lavender and tarragon EEs, which showed the lowest minimal inhibitory concentration against Clostridium tyrobutyricum, were selected to study the prevention of LBD caused by this bacterium in cheese. Addition of savory and lavender EEs to cheese milk delayed LBD by 2 weeks, but at the end of ripening these cheeses showed similar clostridial vegetative cells counts, spoilage symptoms and propionic, and butyric acids levels than blown control cheese. Tarragon EE, with the highest content in caffeic acid, also delayed LBD by 2 weeks, but it was more effective to inhibit Clostridium, since cheese with tarragon EE showed minor LBD symptoms, lower vegetative cells count and lower concentrations of propionic and butyric acids than the rest of cheeses made with EEs. This fact could be also attributable to the greater number of antimicrobial terpenes (1,8-cineole, 4-terpineol, α-terpineol, isoelemicin, methyl eugenol, and methyl trans-isoeugenol) detected in this cheese. This is the first report on the application of EEs to control C. tyrobutyricum in cheese.

Cuban Abdala vaccine: Effectiveness in preventing severe disease and death from COVID-19 in Havana, Cuba; A cohort study.

Background: COVID-19 vaccines have proven safe and efficacious in reducing severe illness and death. Cuban protein subunit vaccine Abdala has shown safety, tolerability and efficacy (92·3% [95% CI: 85·7‒95·8]) against SARS-CoV-2 in clinical trials. This study aimed to estimate Abdala's real-world vaccine effectiveness (VE). Methods: This retrospective cohort study in Havana analyzed Cuban Ministry of Public Health databases (May 12-August 31, 2021) to assess VE in preventing severe illness and death from COVID-19 (primary outcomes). Cox models accounting for time-varying vaccination status and adjusting by demographics were used to estimate hazard ratios. A subgroup analysis by age group and a sensitivity analysis including a subgroup of tested persons (qRT-PCR) were conducted. Daily cases and deaths were modelled accounting for different VE. Findings: The study included 1 355 638 persons (Mean age: 49·5 years [SD: 18·2]; 704 932 female [52·0%]; ethnicity data unavailable): 1 324 vaccinated (partially/fully) and 31 433 unvaccinated. Estimated VE against severe illness was 93·3% (95% CI: 92·1-94·3) in partially- vaccinated and 98·2% (95% CI: 97·9-98·5) in fully-vaccinated and against death was 94·1% (95% CI: 92·5-95·4) in partially-vaccinated and 98·7% (95% CI: 98·3-99·0) in fully-vaccinated. VE exceeded 92·0% in all age groups. Daily cases and deaths during the study period corresponded to a VE above 90%, as predicted by models. Interpretation: The Cuban Abdala protein subunit vaccine was highly effective in preventing severe illness and death from COVID-19 under real-life conditions. Funding: Cuban Ministry of Public Health. Genetic Engineering and Biotechnology Centre.

An engineered SARS-CoV-2 receptor-binding domain produced in Pichia pastoris as a candidate vaccine antigen.

Developing affordable and easily manufactured SARS-CoV-2 vaccines will be essential to achieve worldwide vaccine coverage and long-term control of the COVID-19 pandemic. Here the development is reported of a vaccine based on the SARS-CoV-2 receptor-binding domain (RBD), produced in the yeast Pichia pastoris. The RBD was modified by adding flexible N- and C-terminal amino acid extensions that modulate protein/protein interactions and facilitate protein purification. A fed-batch methanol fermentation with a yeast extract-based culture medium in a 50 L fermenter and an immobilized metal ion affinity chromatography-based downstream purification process yielded 30-40 mg/L of RBD. Correct folding of the purified protein was demonstrated by mass spectrometry, circular dichroism, and determinations of binding affinity to the angiotensin-converting enzyme 2 (ACE2) receptor. The RBD antigen also exhibited high reactivity with sera from convalescent individuals and Pfizer-BioNTech or Sputnik V vaccinees. Immunization of mice and non-human primates with 50 µg of the recombinant RBD adjuvanted with alum induced high levels of binding antibodies as assessed by ELISA with RBD produced in HEK293T cells, and which inhibited RBD binding to ACE2 and neutralized infection of VeroE6 cells by SARS-CoV-2. Additionally, the RBD protein stimulated IFNγ, IL-2, IL-6, IL-4 and TNFα secretion in splenocytes and lung CD3+-enriched cells of immunized mice. The data suggest that the RBD recombinant protein produced in yeast P. pastoris is suitable as a vaccine candidate against COVID-19.

Rituximab in myasthenia gravis: efficacy, associated infections and risk of induced hypogammaglobulinemia.

The aim of this study is to evaluate the long-term efficacy, safety, and impact on immunoglobulin G (IgG) levels of rituximab in patients with myasthenia gravis (MG). A retrospective, observational study of drug-refractory MG patients treated with rituximab was done. The MG Foundation of America postintervention status (MGFA-PIS) was used to evaluate clinical response. Serum IgG levels were determined at baseline and post-treatment. Hypogammaglobulinemia was defined as IgG<7g/L. Thirty patients were included, 12 with anti-MuSK and 18 with anti-AChR antibodies. Mean (SD) follow-up was 85.5 (48) months. All 12 MuSK+ patients but only six (33%) AChR+ patients achieved minimal manifestations or remission (p<0.01). Nine severe infections were observed in five patients (17%). One patient was diagnosed with progressive multifocal leukoencephalopathy. At baseline, two patients (2/24; 8%) had hypogammaglobulinemia. During follow-up, hypogammaglobulinemia was observed in 60% (3/5) of patients who developed an infection and in 33% (7/21) who did not. Two of these patients died of infection-related complications. This study supports the effectiveness of rituximab in patients with MG, especially those with anti-MuSK antibodies. Severe infections may appear after rituximab treatment and hypogammaglobulinemia might play a role on it. A standard protocol would be needed to closely monitor IgG levels in MG patients treated with rituximab.

Genotype-phenotype correlations in valosin-containing protein disease: a retrospective muticentre study.

BACKGROUND: Valosin-containing protein (VCP) disease, caused by mutations in the VCP gene, results in myopathy, Paget's disease of bone (PBD) and frontotemporal dementia (FTD). Natural history and genotype-phenotype correlation data are limited. This study characterises patients with mutations in VCP gene and investigates genotype-phenotype correlations. METHODS: Descriptive retrospective international study collecting clinical and genetic data of patients with mutations in the VCP gene. RESULTS: Two hundred and fifty-five patients (70.0% males) were included in the study. Mean age was 56.8±9.6 years and mean age of onset 45.6±9.3 years. Mean diagnostic delay was 7.7±6 years. Symmetric lower limb weakness was reported in 50% at onset progressing to generalised muscle weakness. Other common symptoms were ventilatory insufficiency 40.3%, PDB 28.2%, dysautonomia 21.4% and FTD 14.3%. Fifty-seven genetic variants were identified, 18 of these no previously reported. c.464G>A (p.Arg155His) was the most frequent variant, identified in the 28%. Full time wheelchair users accounted for 19.1% with a median time from disease onset to been wheelchair user of 8.5 years. Variant c.463C>T (p.Arg155Cys) showed an earlier onset (37.8±7.6 year) and a higher frequency of axial and upper limb weakness, scapular winging and cognitive impairment. Forced vital capacity (FVC) below 50% was as risk factor for being full-time wheelchair user, while FVC <70% and being a full-time wheelchair user were associated with death. CONCLUSION: This study expands the knowledge on the phenotypic presentation, natural history, genotype-phenotype correlations and risk factors for disease progression of VCP disease and is useful to improve the care provided to patient with this complex disease.

Immune Response and Safety of SARS-CoV-2 mRNA-1273 Vaccine in Patients With Myasthenia Gravis.

BACKGROUND AND OBJECTIVES: Evidence regarding the safety and efficacy of messenger RNA (mRNA) vaccines in patients with myasthenia gravis (MG) after immunosuppressive therapies is scarce. Our aim is to determine whether the mRNA-1273 vaccine is safe and able to induce humoral and cellular responses in patients with MG. METHODS: We performed an observational, longitudinal, prospective study including 100 patients with MG of a referral center for MG in our country, conducted from April 2021 to November 2021 during the vaccination campaign. The mRNA-1273 vaccine was scheduled for all participants. Blood samples were collected before vaccination and 3 months after a second dose. Clinical changes in MG were measured using the MG activities of daily life score at baseline and 1 week after the first and second doses. A surveillance of all symptoms of coronavirus disease 2019 (COVID-19) was conducted throughout the study. Humoral and cellular immune responses after vaccination were assessed using a spike-antibody ELISA and interferon gamma release assay in plasma. The primary outcomes were clinically significant changes in MG symptoms after vaccination, adverse events (AEs), and seroconversion and T-cell immune response rates. RESULTS: Ninety-nine patients completed the full vaccination schedule, and 98 had 2 blood samples taken. A statistically significant worsening of symptoms was identified after the first and second doses of the mRNA-1273 vaccine, but this was not clinically relevant. Mild AEs occurred in 14 patients after the first dose and in 21 patients after the second dose. Eighty-seven patients developed a humoral response and 72 patients showed a T-cell response after vaccination. A combined therapy with prednisone and other immunosuppressive drugs correlated with a lower seroconversion ratio (OR = 5.97, 95% CI 1.46-24.09, p = 0.015) and a lower T-cell response ratio (OR = 2.83, 95% CI 1.13-7.13, p = 0.024). DISCUSSION: Our findings indicate that the mRNA vaccination against COVID-19 is safe in patients with MG and show no negative impact on the disease course. Patients achieved high humoral and cellular immune response levels. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that patients with MG receiving the mRNA-1273 vaccine did not show clinical worsening after vaccination and that most of the patients achieved high cellular or immune response levels.

Safety, tolerability, and immunogenicity of a SARS-CoV-2 recombinant spike RBD protein vaccine: A randomised, double-blind, placebo-controlled, phase 1-2 clinical trial (ABDALA Study).

Background: Multiple vaccine candidates against COVID-19 are currently being evaluated. We evaluate the safety and immunogenicity protein of a novel SARS-CoV-2 virus receptor-binding domain (RBD) vaccine. Methods: A phase 1-2, randomised, double-blind, placebo-controlled trial was carried out in "Saturnino Lora" Hospital, Santiago de Cuba, Cuba. Subjects (healthy or those with controlled chronic diseases) aged between 19 and 80 years, who gave written informed consent were eligible. Subjects were randomly assigned (1:1:1, in blocks) to three groups: placebo, 25 µg and 50 µg RBD vaccine (Abdala). The product was administered intramuscularly, 0·5 mL in the deltoid region. During the first phase, two immunization schedules were studied: 0-14-28 days (short) and 0-28-56 days (long). In phase 2, only the short schedule was evaluated. The organoleptic characteristics and presentations of vaccine and placebo were identical. All participants (subjects, clinical researchers, statisticians, laboratory technicians, and monitors) remained masked during the study period. The main endpoints were safety and the proportion of subjects with seroconversion of anti-RBD IgG antibodies, analysed by intention to treat and per protocol, respectively. The trial is registered with the Cuban Public Registry of Clinical Trials, RPCEC00000346. Findings: Between Dec 7, 2020, and Feb 9, 2021, 792 subjects were included; 132 (66 in each vaccination schedule, divided into 22 for each group) in phase 1, and 660 (220 in each group plus 66 from the short scheme of phase 1) in phase 2. The product was well tolerated. No severe adverse events were reported. During phase 1, the incidence of adverse events in the 25 µg, 50 µg, and placebo arms for the short schedule were 6/22 (27·3%), 6/22 (27·3%), 3/22 (13·6%), respectively, and for the long schedule were 8/22 (36·4%), 9/22 (40·9%), 4/22 (18·2%), respectively. In phase 2, adverse reactions were reported by 53/242 (21·9%), 75/242 (31·0%) and 41/242 (16·9%) participants in the 25 µg, 50 µg, and placebo group, respectively. Adverse reactions were minimal, mostly mild, and from the injection site, which resolved in the first 24-48 hours. In phase 1, seroconversion at day 56 was seen in 95·2% of the participants (20/21) in the 50 µg group, 81% (17/21) in the 25 µg group, and none in the placebo group (0/22). For the long schedule, seroconversion at day 70 was seen in 100% of the participants (21/21) in the 50 µg group, 94·7% (18/19) in the 25 µg group, and none in the placebo group (0/22). In phase 2, seroconversion of anti-RBD IgG antibodies at day 56 was seen in 89·2% of the participants in the 50 µg group (214/240; 95% CI 84·5-92·82), 77·7% in the 25 µg group (185/238; 72·0-82·9) and 4·6% in the placebo group (11/239; 2·3-8·1). Compared with the placebo arm, the differences in the proportion of participants with seroconversion were 73·1% (95% CI 66·8-79·5) and 84·6% (79·4-89·7) in the 25 µg and 50 µg groups, respectively. The seroconversion rate in the 50 µg group was significantly higher than in the 25 µg group (p=0·0012). Interpretation: The Abdala vaccine was safe, well tolerated, and induced humoral immune responses against SARS-CoV-2. These results, in the context of the emergency COVID-19 pandemic, support the 50 µg dose, applied in a 0-14-28 days schedule, for further clinical trials to confirm vaccine efficacy. Funding: Centre for Genetic Engineering and Biotechnology (CIGB), Havana, Cuba.

Potential mechanisms involved on how systemic IgG antibodies specific to vascular endothelial growth factor (VEGF) and induced by active immunotherapy decrease platelet derived free-VEGF.

CIGB-247 is a vascular endothelial growth factor (VEGF)-based active immunotherapy and it is currently under investigation for cancer treatment. This specific active immunotherapy encompasses two vaccine candidates that use a human VEGF variant molecule as antigen, in combination with two clinically tested adjuvants: VSSP or aluminum phosphate. CIGB-247 has been evaluated in patients with advanced solid tumors, recruited in two phase I clinical trials, and it has been shown to be safe and immunogenic by activating both cellular and humoral immune responses against human VEGF. The immunization induces specific IgG antibodies, and also shows as effect, the reduction of free-VEGF levels within platelets (platelet-derived free VEGF). The production of systemic IgG antibodies and the presence of VEGF in another compartment, almost exclusively within platelets, have arisen some questions about this effect detected in the vaccinated-cancer patients. Based on some relevant published works about platelet endocytosis and VEGF pharmacodynamics during bevacizumab treatment as well as the phase I clinical data of CIGB-247, this investigation aims to hypothesize and analyze the potential mechanisms involved in the reduction of platelet-derived free VEGF as a result of vaccination with CIGB-247.Abbreviations: FcγR: Fc gamma receptors; IC: immune complexes; VEGF: vascular endothelial growth factor; VEGFR1: vascular endothelial growth factor receptor 1; VEGFR2: vascular endothelial growth factor receptor 2.