POS1214 COVID-19 VACCINATION RATE AND SAFETY PROFILE IN PATIENTS AFFECTED BY MIXED CRYOGLOBULINEMIC VASCULITIS

Background

Mixed cryoglobulinaemic vasculitis (MCV) is an immune-complex-mediated systemic vasculitis characterized by heterogeneous clinical manifestations mainly involving skin, kidney and peripheral nervous system.

Despite reassuring safety data from EULAR Coronavirus Vaccine (COVAX) physician-reported registry, a significant proportion of patients with autoimmune diseases reported unwillingness to get vaccinated against SARS-CoV-2 infection in the preliminary results of the COVAD study, due to concerns about the lack of long-term safety data, and fear of associated side effects and disease flare.

Objectives

Aims of this multicentre Italian study were to investigate the prevalence of vaccination against SARS-CoV-2 in Italian population of MCV patients, to explore the reason for the missed vaccination, and to investigate short and long-term side effects of the vaccine, including vasculitis flare.

Methods

All MCV patients referring to 12 Italian centres were investigated about vaccination and possible both short- (within 48 hours) and long-term (within 30 days) adverse events (AE), classified according to FDA Toxicity Grading Scale for preventive vaccine clinical trials, and possible disease flares. Patients with MCV related to lymphoproliferative disorders or connective tissue diseases were excluded from the study.

The baseline variables were expressed as percentages or mean±standard deviation. The differences between continuous variables were analysed using the Mann–Whitney nonparametric test. The chi-squared test, or Fischer’s exact when appropriate, were used for categorical variables (absolute numbers and percentages) regarding baseline characteristics.

Results

A total of 416 patients, 69.2% females and 30.8% males, with a mean age of 70.4±11.7 years, were included in the study.

Only 7.7% of patients were not vaccinated, mainly for fear of adverse events (50%) or for medical decision (18.8%). Corminaty was the vaccine most frequently used (80.5%). Interestingly, 6 patients (1.44%) were with a heterologous vaccination (usually AstraZeneca-Corminaty).

Considering ongoing treatment, not vaccinated subjects were more frequently treated with chronic glucocorticoid therapy and/or Rituximab (p=0.049 and p=0.043 respectively).

AE were recorded in 31.7% of cases, mainly mild and self-limiting (grade 1). More severe adverse events, such as flare of vasculitis, were observed in 5.3% of cases.

AE were not associated with the kind of vaccine used and with the clinical manifestations of vasculitis. Patients with active MCV showed a lower frequency of short-term (within 48 hours) adverse events, but patients affected by peripheral neuropathies or skin vasculitis frequently showed a flare of their symptoms, recorded in 40% and 25% of cases, respectively. Finally, patients under glucocorticoid treatment were more prone to develop a vasculitis flare within a month after vaccination.

Conclusion

Vaccination in MCV patients has been performed in a high percentage of patients showing a good safety. Other than patients’ fear, treatments with rituximab and glucocorticoids are the main reasons for delaying vaccination, and it should be considered by the physician before starting therapy. Vasculitis flares were observed in about 5% of cases, in line with that observed in other autoimmune diseases. Specific attention should be reserved to people with purpura or peripheral neuropathy, for the increased risk of exacerbation of their symptoms.

References

[1]Visentini M et al Flares of mixed cryoglobulinaemia vasculitis after vaccination against SARS-CoV-2 2021

[2]Machado PM et al Safety of vaccination against SARS-CoV-2 in people with rheumatic and musculoskeletal diseases: results from the EULAR Coronavirus Vaccine COVAX physician-reported registry 2021

[3]Sen P et al COVAD Study Group. COVID-19 vaccination in autoimmune disease COVAD survey protocol 2022

[4]Scarpato S et al Italian Group for the Study of Cryoglobulinaemia GISC. Provisional recommendations for SARS-CoV-2 vaccination in patients with cryoglobulinaemic vasculitis 2021

Disclosure of Interests

None declared

AB1169 IMMUNOMODULATORY EFFECTS OF SARS-CoV-2 VACCINATION: INCREASE OF REGULATORY T CELLS AFTER mRNA VACCINE

Background

Besides the ability to induce antigen-specific responses, vaccines can be endowed with immunomodulatory properties including the capacity to induce or downregulate regulatory T cells (Treg) that suppress adaptative and autoreactive immune responses (1).

Objectives

We asked if an anti-SARS-CoV-2 mRNA vaccine could also induce an accumulation of Treg cells in patients with mixed cryoglobulinemia vasculitis (MCV), who have a deficiency of Treg cells (2) and in healthy individuals. We also investigated immunologic variables possibly associated with a low immunogenicity of SARS-CoV-2 mRNA vaccine in patients with MCV (3).

Methods

We analyzed peripheral blood lymphocyte subpopulations and anti-SARS-CoV-2 serological response in 24 patients with MCV and 9 Healthy donors (HD) before and after 2 weeks after the second dose of the Pfizer/BioNTech vaccine.

Results

Among MCV patients we found 15 serological responders and 9 non-responders. All 5 seronegative patients treated recently with rituximab had <5 B cells/µL, whereas the absolute B cell count was increased in 2 of 4 untreated patients due to monoclonal B cell lymphocytosis, with monoclonal cells representing more than 90% of B cells, associated with non-Hodgkin lymphoma. The percentage of pathologic CD21low B cells was significantly increased in seronegative patients.

Before receiving the Pfizer/BioNTech vaccine, patients with MCV had a significantly reduced frequency of Treg cells among CD4+ T cells compared to HD. After the second dose of the vaccine, there was in MCV patients a significant increase in the percent and absolute count of Treg among CD4+ T cells

Concerning the pre-vaccination distribution of T cells subpopulations, including the percentages and absolute counts of total CD3+, CD4+, CD8+, HLA-DR+ activated, Treg or CD56+ natural killer T cells, we could not reveal any pattern significantly associated with lack of serological response to vaccine.

Conclusion

Our findings show that lack of immunoreactivity in patients with MCV may be associated with expansion of pathologic B cells and that anti-SARS-CoV2 mRNA vaccine may induce an increase of Treg cells.

References

[1]Krienke C. et al. A noninflammatory mRNA vaccine for treatment of experimental autoimmune encephalomyelitis. Science. 2021 Jan 8;371(6525):145-153.

[2]Boyer O. et al. CD4+CD25+ regulatory T-cell deficiency in patients with hepatitis C-mixed cryoglobulinemia vasculitis. Blood. 2004 May 1;103(9):3428-30.

[3]Visentini M. et al. Flares of mixed cryoglobulinaemia vasculitis after vaccination against SARS-CoV-2. Ann Rheum Dis. 2021 Nov 24:annrheumdis-2021-221248.

Disclosure of Interests

None declared

Serum immunoglobulin free light chain levels in systemic autoimmune rheumatic diseases

Several reports have highlighted the abnormal increments of serum immunoglobulin free light chains (FLCs) in the course of systemic autoimmune rheumatic diseases (SARD), but a comparative analysis among different conditions is still lacking. A strong association between elevated FLC and hepatitis C virus (HCV)-related mixed cryoglobulinaemia (HCVMC) has been well established. Here, we aimed to analyse serum FLC levels in patients with four different SARD in comparison with HCVMC. Using a turbidimetric assay, free κ and λ chains were quantified in sera from 198 SARD patients (37 rheumatoid arthritis, RA; 47 systemic lupus erythematosus, SLE; 52 anti-phospholipid syndrome, APS; 62 primary Sjogren's syndrome, pSS), 62 HCVMC and 50 healthy blood donors (HD). All patient groups showed increased κ levels when compared to HD: 33·5 ± 2·6 mg/l in HCVMC, 26·7 ± 2·3 mg/l in RA, 29·7 ± 1·9 mg/l in SLE, 23·8 ± 1·1 mg/l in APS, 24·2 ± 1·1 mg/l in pSS; 10·1 ± 0·6 mg/l in HD. Free λ levels displayed a significant increase only for HCVMC (20·4 ± 1·4 mg/l) and SLE (18·4 ± 1·0 mg/l) compared to HD (13·6 ± 0·9 mg/l). The increase of κ compared to λ takes into account a κ /λ ratio of 1·6 for all groups. Our results substantially analyse and strengthen the association between FLC and SARD focusing the questions regarding their role in the pathogenesis and diagnosis of human diseases. Unfortunately, the biochemical differences distinguishing normal from pathological FLC have not been identified. Production of different isotypes is probably connected to still-unknown pathways.

Hepatitis B virus-related cryogobulinemic vasculitis. The role of antiviral nucleot(s)ide analogues: a review

Cryoglobulinemic vasculitis (CV) can develop in 1.2-4% of hepatitis B virus (HBV)-infected patients. HBV infection affects about 350 million people worldwide. It can progress from acute or fulminant hepatitis to chronic hepatitis, cirrhosis or hepatocellular carcinoma. Twenty per cent of HBV patients may develop extra-hepatic manifestations, such as polyarteritis nodosa, glomerulonephritis, dermatitis, polyarthralgias and arthritis, lung disease, aplastic anaemia. Our review focuses on the role of antiviral agent nucleot(s)ide analogues (NAs) in treatment of HBV-related CV. The studies in literature have demonstrated that NAs therapy in HBV-related CV yields high virological and satisfying clinical responses in most patients with mild-and-moderate CV, but a low response in severe CV. Overall, NAs represent a promising therapeutic option for HBV-related CV. Obtaining early suppression of HBV viral load should be the main virological and clinical goal in order to prevent organ complications and lymphoproliferative disorders.

Targeting of ADAMTS5's ancillary domain with the recombinant mAb CRB0017 ameliorates disease progression in a spontaneous murine model of osteoarthritis

OBJECTIVE

ADAMTS5 (aggrecanase-2) has been demonstrated to be crucial in the development of osteoarthritis (OA), by use of several mouse mutants carrying either truncated, catalytically inactive enzymes or aggrecanase-resistant mutant aggrecan. We have selected recombinant monoclonal antibodies directed against ADAMTS5, by using Intracellular Antibody Capture Technology (IACT). CRB0017 revealed very high affinity for the enzyme in Biacore analyses and very good specificity in a panel of binding assays. Therefore, we tested CRB0017 in a relevant spontaneous OA model, the STR/ort mouse.

DESIGN

STR/ort male mice were recruited at 5 months of age, and treated intra-articularly in each knee with CRB0017 1.2 μg, CRB0017 12 μg, or vehicle. After 6 weeks, the intra-articular administration of CRB0017 was repeated with the same doses. After 3 months from recruitment, the animals were sacrificed and the femorotibial joints processed for histology and scored in a blind fashion according to both Mankin's and the OARSI methods.

RESULTS AND CONCLUSIONS

All histological scores were significantly decreased in the CRB0017 12 μg/knee group compared to vehicle, while administration of CRB0017 1.2 μg was associated with a trend to a decrease in the same parameters. Therefore, CRB0017 administered twice in 3 months could modify the course of OA in the STR/ort mouse, by delaying cartilage breakdown as assessed histologically. The procedure of blind scoring of the histological samples clearly showed that knee intra-articular administration of CRB0017, an anti-ADAMTS5 antibody, dose-dependently improved disease progression in a relevant animal model of OA.

A simultaneous occurrence of Tolosa-Hunt syndrome and fibrillary glomerulonephritis: a case report

Fibrillary glomerulonephritis (FibGN) is a rare cause of progressive renal dysfunction, often leading to dialysis within a few years. A 60-year-old woman presented with a 2 month history of right-sided retro-orbital pain and recent diplopia. Laboratory testing revealed an altered renal function with increased serum creatinine and mild proteinuria. MRI of the brain revealed the presence of a soft tissue mass on the right cavernous sinus compatible with the diagnosis of Tolosa-Hunt syndrome (THS). Renal biopsy showed a pattern compatible with fibrillary glomerulonephritis. For this reason steroid therapy was initiated at a dose of 1 mg/kg/day and adjusted according to the clinical course. Neurological symptoms regressed shortly after the beginning of therapy and renal function and proteinuria remained stable for the 3 years following the withdrawal of steroid therapy. Percutaneous renal biopsy was again performed and confirmed the previous diagnosis of FibGN in association with other glomerular-lesion-like mesangial widening, thickening of capillary walls and severe arterio-arteriolosclerosis. This case report describes what is believed to first report of the association of FibGN and THS, which both responded to steroid therapy.

MicroRNA gene expression during retinoic acid-induced differentiation of human acute promyelocytic leukemia

MicroRNAs (miRNAs) are small non-coding RNAs of 19-25 nucleotides that are involved in the regulation of critical cell processes such as apoptosis, cell proliferation and differentiation. However, little is known about the role of miRNAs in granulopoiesis. Here, we report the expression of miRNAs in acute promyelocytic leukemia patients and cell lines during all-trans-retinoic acid (ATRA) treatment by using a miRNA microarrays platform and quantitative real time-polymerase chain reaction (qRT-PCR). We found upregulation of miR-15a, miR-15b, miR-16-1, let-7a-3, let-7c, let-7d, miR-223, miR-342 and miR-107, whereas miR-181b was downregulated. Among the upregulated miRNAs, miR-107 is predicted to target NFI-A, a gene that has been involved in a regulatory loop involving miR-223 and C/EBPa during granulocytic differentiation. Indeed, we have confirmed that miR-107 targets NF1-A. To get insights about ATRA regulation of miRNAs, we searched for ATRA-modulated transcription factors binding sites in the upstream genomic region of the let-7a-3/let-7b cluster and identified several putative nuclear factor-kappa B (NF-kappaB) consensus elements. The use of reporter gene assays, chromatin immunoprecipitation and site-directed mutagenesis revealed that one proximal NF-kappaB binding site is essential for the transactivation of the let-7a-3/let-7b cluster. Finally, we show that ATRA downregulation of RAS and Bcl2 correlate with the activation of known miRNA regulators of those proteins, let-7a and miR-15a/miR-16-1, respectively.