Safety of Repeated Administration of Xenogeneic Human Apoptotic State (Allocetra-OTS) in Sprague Dawley Rats.

Apoptotic cells possess immunomodulatory effects that can be utilized to treat imbalanced immune conditions. Information on the preclinical safety of such treatment is sparse. In this study, the safety of apoptotic cells (Allocetra-OTS) was assessed in a GLP toxicological study on Sprague Dawley rats. Three doses of Allocetra-OTS or vehicle were administered intravenously (IV) for 3 consecutive days. Animals in the main study were sacrificed on day 4, while animals from the recovery groups were kept for 14 or 28 days. Allocetra-OTS was well tolerated, and no adverse effects were observed in terms of body weight, clinical signs, food consumption, or ophthalmologic observation. Thus, the No Observed Adverse Effect Level (NOAEL) dose was determined as the highest dose administered. An observed elevation in immune cells was suspected to be due to Allocetra-OTS, similarly to other clinical chemistry parameters; however, it was resolved in the recovery phases. Splenomegaly and dose-related extramedullary hematopoiesis (EMH) in the red pulp were observed, with no adverse events, and were considered to be a normal and expected reaction following the IV administration of cell-based therapies. In conclusion, under the conditions of this study, Allocetra-OTS was concluded to be safe, further supporting its potential candidacy for clinical studies.

HLA binding-groove motifs are associated with myocarditis induction after Pfizer-BioNTech BNT162b2 vaccination.

BACKGROUND AND AIMS: We found a higher incidence of myocarditis in young males who had received at least two Pfizer-BioNTech BNT162b2 vaccinations. The human leukocyte antigens (HLA) are known to play an important role in infectious and autoinflammatory diseases. We hypothesized that certain HLA alleles might be associated with vaccination-induced myocarditis. METHODS: HLA typing was performed using next-generation sequencing technology with the Illumina Iseq100 platform. HLA class I and II loci were genotyped in 29 patients with post-vaccination myocarditis and compared with HLA data from 300 healthy controls. RESULTS: We demonstrate that the DRB1*14:01, DRB1*15:03 alleles and the motifs in HLA-A - Leu62 and Gln63, which are part of binding pocket B and HLA-DR Tyr47, His60, Arg70 and Glu74, which are part of binding pockets P4, P7 and P9, were significantly associated with disease susceptibility. CONCLUSIONS: Our findings suggest that immunogenetic fingerprints in HLA peptide-binding grooves may affect the presentation of peptides derived from the Pfizer-BioNTech BNT162b2 vaccination to T cells and induce an inflammatory process that results in myocarditis.

Complement-membrane regulatory proteins are absent from the nodes of Ranvier in the peripheral nervous system.

BACKGROUND: Homozygous CD59-deficient patients manifest with recurrent peripheral neuropathy resembling Guillain-Barré syndrome (GBS), hemolytic anemia and recurrent strokes. Variable mutations in CD59 leading to loss of function have been described and, overall, 17/18 of patients with any mutation presented with recurrent GBS. Here we determine the localization and possible role of membrane-bound complement regulators, including CD59, in the peripheral nervous systems (PNS) of mice and humans. METHODS: We examined the localization of membrane-bound complement regulators in the peripheral nerves of healthy humans and a CD59-deficient patient, as well as in wild-type (WT) and CD59a-deficient mice. Cross sections of teased sciatic nerves and myelinating dorsal root ganglia (DRG) neuron/Schwann cell cultures were examined by confocal and electron microscopy. RESULTS: We demonstrate that CD59a-deficient mice display normal peripheral nerve morphology but develop myelin abnormalities in older age. They normally express myelin protein zero (P0), ankyrin G (AnkG), Caspr, dystroglycan, and neurofascin. Immunolabeling of WT nerves using antibodies to CD59 and myelin basic protein (MBP), P0, and AnkG revealed that CD59 was localized along the internode but was absent from the nodes of Ranvier. CD59 was also detected in blood vessels within the nerve. Finally, we show that the nodes of Ranvier lack other complement-membrane regulatory proteins, including CD46, CD55, CD35, and CR1-related gene-y (Crry), rendering this area highly exposed to complement attack. CONCLUSION: The Nodes of Ranvier lack CD59 and are hence not protected from complement terminal attack. The myelin unit in human PNS is protected by CD59 and CD55, but not by CD46 or CD35. This renders the nodes and myelin in the PNS vulnerable to complement attack and demyelination in autoinflammatory Guillain-Barré syndrome, as seen in CD59 deficiency.

Apoptotic cells for treatment of acute respiratory distress syndrome associated with COVID-19.

Background: Hyper-inflammatory immune response, a hallmark of severe COVID-19, is associated with increased mortality. Acute respiratory distress syndrome (ARDS) is a common manifestation. We undertook two phase I/II studies in five and then 16 subjects with severe/critical COVID-19 to assess the safety and preliminary efficacy of apoptotic cells (Allocetra™-OTS, Enlivex Therapeutics), a cellular immunomodulatory therapy that reprograms macrophages to reduce hyper-inflammatory response severity. Methods: Eligible patients presenting to the Emergency Room with severe COVID-19 and respiratory dysfunction received one intravenous administration of Allocetra™-OTS and were monitored for adverse events (AEs) for 28 days. The primary aim was to determine the safety profile of treatment; secondary aims were recovery from ARDS, intensive care unit (ICU) and hospital length-of-stay, and mortality. Immune modulator markers were measured to elucidate the mechanism of action of Allocetra™-OTS. Results: 21 patients with severe-critical COVID-19 of Gamma, Alpha and Delta variants, were treated with a single dose of apoptotic cells. 19/21 patients had mild-to-severe ARDS at presentation. Median age was 53 years, 16/21 were males, 16/21 were overweight/obese. No serious related adverse events (SAEs) were reported. All 21 study subjects survived to day 28 (end of study); 19/21 recovered completely. Comparable mortality rates at the hospital were 3.8%-8.9% for age- and gender-matched patients, and 39%-55% for critical patients. Recovering patients exhibited rapid ARDS resolution and parallel resolution of inflammation markers and elevated cytokines/chemokines. Conclusion: In patients with severe/critical COVID-19 associated with ARDS, Allocetra™-OTS was safe, well-tolerated, and showed promising results for resolution of respiratory failure and inflammation. Trial registration: https://clinicaltrials.gov/ct2/show/study/NCT04513470, https://clinicaltrials.gov/ct2/show/study/NCT04590053, Identifiers NCT04513470, NCT04590053.

A deep look into the storm: Israeli multi-center experience of coronavirus disease 2019 (COVID-19) in patients with autoimmune inflammatory rheumatic diseases before and after vaccinations.

Objective: We aimed to characterize the course of COVID-19 in autoimmune inflammatory rheumatic disease (AIIRD) patients in Israel, taking into consideration several remarkable aspects, including the outcomes of the different outbreaks, the effect of vaccination campaigns, and AIIRD activity post-recovery. Methods: We established a national registry of AIIRD patients diagnosed with COVID-19, including demographic data, AIIRD diagnosis, duration and systemic involvement, comorbidities, date of COVID-19 diagnosis, clinical course, and dates of vaccinations. COVID-19 was diagnosed by a positive SARS-CoV-2 polymerase chain reaction. Results: Israel experienced 4 outbreaks of COVID-19 until 30.11.2021. The first three outbreaks (1.3.2020 - 30.4.2021) comprised 298 AIIRD patients. 64.9% had a mild disease and 24.2% had a severe course; 161 (53.3%) patients were hospitalized, 27 (8.9%) died. The 4th outbreak (delta variant), starting 6 months after the beginning of the vaccination campaign comprised 110 patients. Despite similar demographic and clinical characteristics, a smaller proportion of AIIRD patients had negative outcomes as compared to the first 3 outbreaks, with regards to severity (16 patients,14.5%), hospitalization (29 patients, 26.4%) and death (7 patients, 6.4%). COVID-19 did not seem to influence the AIIRD activity 1-3 months post-recovery. Conclusions: COVID-19 is more severe and has an increased mortality in active AIIRD patients with systemic involvement, older age and comorbidities. Vaccination with 3 doses of the mRNA vaccine against SARS-CoV-2 protected from severe COVID-19, hospitalization and death during the 4th outbreak. The pattern of spread of COVID-19 in AIIRD patients was similar to the general population.

Use of Colchicine for Pericardial Inflammation: Risks and Toxicities-A Cautionary Tale.

Colchicine is commonly used as part of the treatment of acute and recurrent pericarditis. Neuromyopathy is a well-known, but probably underreported, side effect of colchicine. Here we present a unique case of a 56-year-old woman with recurrent episodes of colchicine-induced neuromyopathy over many years. (Level of Difficulty: Beginner.).

Apoptotic Cells for Therapeutic Use in Cytokine Storm Associated With Sepsis- A Phase Ib Clinical Trial.

Background: Sepsis has no proven specific pharmacologic treatment and reported mortality ranges from 30%-45%. The primary aim of this phase IB study was to determine the safety profile of Allocetra™-OTS (early apoptotic cell) infusion in subjects presenting to the emergency room with sepsis. The secondary aims were to measure organ dysfunction, intensive care unit (ICU) and hospital stays, and mortality. Exploratory endpoints included measuring immune modulator agents to elucidate the mechanism of action. Methods: Ten patients presenting to the emergency room at the Hadassah Medical Center with sepsis were enrolled in this phase Ib clinical study. Enrolled patients were males and females aged 51-83 years, who had a Sequential Organ Failure Assessment (SOFA) score ≥2 above baseline and were septic due to presumed infection. Allocetra™-OTS was administered as a single dose (day +1) or in two doses of 140×106 cells/kg on (day +1 and +3), following initiation of standard-of-care (SOC) treatment for septic patients. Safety was evaluated by serious adverse events (SAEs) and adverse events (AEs). Organ dysfunction, ICU and hospital stays, and mortality, were compared to historical controls. Immune modulator agents were measured using Luminex® multiplex analysis. Results: All 10 patients had mild-to-moderate sepsis with SOFA scores ranging from 2-6 upon entering the study. No SAEs and no related AEs were reported. All 10 study subjects survived, while matched historical controls had a mortality rate of 27%. The study subjects exhibited rapid resolution of organ dysfunction and had significantly shorter ICU stays compared to matched historical controls (p<0.0001). All patients had both elevated pro- and anti-inflammatory cytokines, chemokines, and additional immune modulators that gradually decreased following treatment. Conclusion: Administration of apoptotic cells to patients with mild-to-moderate sepsis was safe and had a significant immuno-modulating effect, leading to early resolution of the cytokine storm. Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT03925857. (https://clinicaltrials.gov/ct2/show/study/NCT03925857).

Myocarditis after BNT162b2 mRNA Vaccine against Covid-19 in Israel.

BACKGROUND: Approximately 5.1 million Israelis had been fully immunized against coronavirus disease 2019 (Covid-19) after receiving two doses of the BNT162b2 messenger RNA vaccine (Pfizer-BioNTech) by May 31, 2021. After early reports of myocarditis during adverse events monitoring, the Israeli Ministry of Health initiated active surveillance. METHODS: We retrospectively reviewed data obtained from December 20, 2020, to May 31, 2021, regarding all cases of myocarditis and categorized the information using the Brighton Collaboration definition. We analyzed the occurrence of myocarditis by computing the risk difference for the comparison of the incidence after the first and second vaccine doses (21 days apart); by calculating the standardized incidence ratio of the observed-to-expected incidence within 21 days after the first dose and 30 days after the second dose, independent of certainty of diagnosis; and by calculating the rate ratio 30 days after the second dose as compared with unvaccinated persons. RESULTS: Among 304 persons with symptoms of myocarditis, 21 had received an alternative diagnosis. Of the remaining 283 cases, 142 occurred after receipt of the BNT162b2 vaccine; of these cases, 136 diagnoses were definitive or probable. The clinical presentation was judged to be mild in 129 recipients (95%); one fulminant case was fatal. The overall risk difference between the first and second doses was 1.76 per 100,000 persons (95% confidence interval [CI], 1.33 to 2.19), with the largest difference among male recipients between the ages of 16 and 19 years (difference, 13.73 per 100,000 persons; 95% CI, 8.11 to 19.46). As compared with the expected incidence based on historical data, the standardized incidence ratio was 5.34 (95% CI, 4.48 to 6.40) and was highest after the second dose in male recipients between the ages of 16 and 19 years (13.60; 95% CI, 9.30 to 19.20). The rate ratio 30 days after the second vaccine dose in fully vaccinated recipients, as compared with unvaccinated persons, was 2.35 (95% CI, 1.10 to 5.02); the rate ratio was again highest in male recipients between the ages of 16 and 19 years (8.96; 95% CI, 4.50 to 17.83), with a ratio of 1 in 6637. CONCLUSIONS: The incidence of myocarditis, although low, increased after the receipt of the BNT162b2 vaccine, particularly after the second dose among young male recipients. The clinical presentation of myocarditis after vaccination was usually mild.

A novel loss-of-function mutation in LACC1 underlies hereditary juvenile arthritis with extended intra-familial phenotypic heterogeneity.

OBJECTIVE: To investigate phenotypic and molecular characteristics of a consanguineous family with autosomal-recessive, polyarticular, juvenile isiopathic arthriris (JIA) with extra-articular manifestations, including renal amyloidosis and Crohn's disease, associated with a novel homozygous truncating variant in LACC1. METHODS: Whole exome sequencing (WES) or targeted Sanger verification were performed in 15 participants. LACC1 expression and cytokine array were analysed in patient-derived and CRISPR/Cas9-generated LACC1-knockout macrophages (Mϕ). RESULTS: A homozygous truncating variant (p.Glu348Ter) in LACC1 was identified in three affected and one asymptomatic family member, and predicted harmful by causing premature stop of the LACC1 protein sequences, and by absence from ethnically-matched controls and public variation databases. Expression studies in patient-derived macrophages (Mϕ) showed no endogenous p.Glu348Ter-LACC1 RNA transcription or protein expression, compatible with nonsense-mediated mRNA decay. WES analysis in the asymptomatic homozygous subject for p. Glu348Ter-LACC1 detected an exclusive heterozygous variant (p.Arg928Gln) in complement component C5. Further complement activity analysis suggested a protective role for the p.Arg928Gln-C5 variant as a phenotypic modifier of LACC1-associated disease. Finally, cytokine profile analysis indicated increased levels of pro-inflammatory cytokines in LACC1-disrupted as compared with wild-type Mϕ. CONCLUSIONS: Our findings reinforce the role of LACC1 disruption in autosomal-recessive JIA, extend the clinical spectrum and intra-familial heterogeneity of the disease-associated phenotype, indicate a modulatory effect of complement factor C5 on phenotypic severity, and suggest an inhibitory role for wild-type LACC1 on pro-inflammatory pathways.

Anti-RhD antibody therapy modulates human natural killer cell function.

Anti-RhD antibodies are widely used in clinical practice to prevent immunization against RhD, principally in hemolytic disease of the fetus and newborn. Intriguingly, this disease is induced by production of the very same antibodies when an RhD negative woman is pregnant with an RhD positive fetus. Despite over five decades of use, the mechanism of this treatment is, surprisingly, still unclear. Here we show that anti-RhD antibodies induce human natural killer (NK) cell degranulation. Mechanistically, we demonstrate that NK cell degranulation is mediated by binding of the Fc segment of anti-RhD antibodies to CD16, the main Fcγ receptor expressed on NK cells. We found that this CD16 activation is dependent upon glycosylation of the anti-RhD antibodies. Furthermore, we show that anti-RhD antibodies induce NK cell degranulation in vivo in patients who receive this treatment prophylactically. Finally, we demonstrate that the anti-RhD drug KamRho enhances the killing of dendritic cells. We suggest that this killing leads to reduced activation of adaptive immunity and may therefore affect the production of anti-RhD antibodies.

Immune imitation of tumor progression after anti-CD19 chimeric antigen receptor T cells treatment in aggressive B-cell lymphoma.

We present three patients with aggressive non-Hodgkin's B-cell lymphoma (NHL) who received anti-CD19 chimeric antigen receptor T (CAR T) cells therapy after failure of several lines of chemotherapy that developed pseudo-progression. One-week clinical and radiological findings were consistent with tumor progression. Positron emission tomography-computed tomography (PET-CT) at 1 month post CAR T cells administration was consistent with treatment response. The rapid tumor growth and subsequent resolution are suggestive of tumor pseudo-progression mediated secondary to infiltration and immune activation of CAR T cells. Overall, 56 adult patients with NHL were enrolled in a phase 1b/2 in house clinical study with CD19 CAR T cells. Out of them 22/56 patients progressed as per PET-CT the 1 month post CAR T cells. In 14 patients, signs of progression started 7-10 days after CAR T cells infusion. In 11/14 patients, it was true progression, while in 3 it was pseudo-progression. Additional studies are warranted to describe the extent of this phenomenon and evaluate correlation with the CAR T activity and long-term disease control.

Serological and hematological characteristics of Sjogren's syndrome and dry eye syndrome patients using a novel immune serology technique.

OBJECTIVES: To compare hematologic and serological parameters among patients with Sjogren's syndrome (SS), dry eye syndrome (DES) and controls, and validate a novel multiplex-serology method for identifying auto-antibodies in these populations. METHODS: In a clinic-based case-control study a total of 422 participants were recruited, including 91 with SS, 120 DES, and 211 controls (age and sex frequency-matched). We measured blood counts, anti-nuclear-antibodies (ANA), anti-SSA/SSB, anti-ribonucleoprotein (RNP), anti-double-stranded-DNA (DS-DNA), and rheumatoid factor (RF) using the "Immunodot" qualitative-ELISA assay. Immunoglobulins, C3 and C4 were measured by immune-fluorescence. Autoantibodies were also quantified with a newly-developed method using glutathione-S-transferase fusion proteins of SSA/Ro 52 and 60kD and SSB/La (multiplex-serology), measuring median fluorescence intensity (MFI). RESULTS: Among DES patients, only 2% (95%CI: 0.36-6.3) had positive immune serology. SS patients had lower lymphocyte, hemoglobin and C3 levels but higher prevalence of RF, ANA, anti-SSA/B and higher IgG and MFI levels, compared to DES and controls (P<0.001). Presence of anti-SSA/Ro-52kD was associated with SS [odds ratio (OR) = 2.05, 95% confidence interval (CI): 1.46-2.88]. Anti-SSB/La was inversely associated with DES (OR = 0.81, 95%CI: 0.65-1.00) compared to controls. Positivity to RF (adjusted for age, gender and ethnicity OR = 5.03, 95%CI: 1.78-14.21), ANA (OR = 14.75, 95%CI: 4.09-53.17), or combination of anti-SSA/B (OR = 20.97, 95%CI: 4.60-95.54) were more likely in SS compared to DES. The novel multiplex-serology method correctly identified anti-SSA/B autoantibodies by ELISA among SS, DES patients and controls (sensitivity = 1.0, negative-predictive-value = 1.0). CONCLUSIONS: Serologic parameters distinguish SS from DES patients and controls. A newly-developed multiplex-serology technique may be useful to detect autoantibodies in large epidemiologic studies.

Immune-Mediated Fetal Complete Atrioventricular Block: Can Dexamethasone Therapy Revert the Process?

BACKGROUND: Fetal complete atrioventricular block (CAVB) is usually autoimmune mediated. The risk of developing CAVB is 2% to 3% in anti-Ro/SS-A seropositive pregnancies and it increases 10 times after previous CAVB in siblings. Despite being a rare complication, CAVB carries a 20% mortality rate and substantial morbidity, as about 65% of newborns will eventually need life-long pacing. Once found, fetal CAVB is almost always irreversible, despite aggressive immunotherapy. This poor outcome prompted some research groups to address this situation. All groups followed anti-Ro/SS-A seropositive pregnancies on a weekly basis during the second trimester of pregnancy and tried to detect first degree atrioventricular block (AVB) using accurate echocardiographic tools, assuming they may characterize the initiation of the immune damage to the A-V conduction system, at which point the process might still be reversible. Some of the groups treated fetuses with first degree AVB with maternal oral fluorinated steroids. We summarized the results of all groups, including our group. We describe a case of a fetus that developed CAVB 6 days after normal sinus rhythm (NSR), who under aggressive dexamethasone therapy gradually reverted to NSR. This fetus had a previous sibling with CAVB. We assumed the immune damage to the conduction system in this small group of fetuses with a previous CAVB sibling may have occurred more quickly than usual. We therefore recommend a twice-weekly follow-up with these fetuses.

A Study of the Efficacy and Safety of Subcutaneous Injections of Tocilizumab in Adults with Rheumatoid Arthritis.

BACKGROUND: Tocilizumab is an interleukin 6 (IL-6) receptor antagonist used treat moderate to severe active rheumatoid arthritis (RA). Both intravenous (IV) and subcutaneous (SC) routes are approved for the treatment of adults with RA. OBJECTIVES: To evaluate SC tocilizumab in a real-life clinical setting. METHODS: Our study was a multi-center, open-label, single-arm study. Participants were adults with a diagnosis of active RA, previously treated with disease-modifying antirheumatic drugs (DMARDs), with or without biologic agents. Participants received a weekly SC injection of tocilizumab 162 mg as monotherapy or in combination with methotrexate or DMARDs for 24 weeks. Efficacy, safety, and immunogenicity were assessed. RESULTS: Treatment of 100 patients over 24 weeks resulted in improvement in all efficacy parameters assessed: Clinical Disease Activity Index, Disease Activity Score using 28 joint counts and erythrocyte sedimentation rate, American College of Rheumatology response scores, Simplified Disease Activity Index, tender and swollen joint counts, and patient-reported outcomes including fatigue, global assessment of disease activity, pain, and Health Assessment Quality of Life Disease Index. Improvement was achieved as early as the second week of treatment. There were 473 adverse events (AEs)/100 patient-years (PY) and 16.66 serious AEs/100 PY. The most common AEs were neutropenia (12%), leukopenia (11%), and increased hepatic enzymes (11%). Of a total of 42 PY, the rates of serious infections and AEs leading to discontinuation were 4.8, and 11.9 events/100 PY, respectively. CONCLUSIONS: The safety, tolerability, and efficacy profile of tocilizumab SC were comparable to those reported in other studies evaluating the IV and SC routes of administration.

Apoptotic cell therapy for cytokine storm associated with acute severe sepsis.

Sepsis has no proven pharmacologic treatment other than appropriate antibiotic agents, fluids, vasopressors as needed, and possibly corticosteroids. It is generally initiated mainly by the simultaneous recognition by various components of the innate immune system of either pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs). In the current study, we employed the murine cecal ligation and puncture (CLP) model for sepsis to evaluate the effect of post-CLP infusion of apoptotic cells (Allocetra-OTS) on a CLP severe sepsis model. Cardiovascular evaluation, acute kidney injury (AKI), acute liver injury (ALI), and hematological and metabolic function were evaluated. Cytokine and chemokine profiles were measured by Multiplex ELISA and mitochondrial function, and glycolysis by Seahorse. The Murine Sepsis Score (MSS) was used for disease severity definition. CLP mice had low blood pressure, poor cardiac output, and lung dysfunction, as well as AKI, ALI, and thrombocytopenia, which correlated with the MSS and corresponded to a cytokine/chemokine storm. Apoptotic cell administration markedly improved the cytokine and chemokine storm and restored the impaired mitochondrial and glycolytic function in white blood cells leading to increased survival, from 6 to 60% (P < 0.0001), together with a significant improvement in organ dysfunction. We conclude that the deleterious immune response in CLP-induced sepsis can be successfully modified by apoptotic cell infusion.