Increased synovial galectin-3 induce inflammatory fibroblast activation and osteoclastogenesis in patients with rheumatoid arthritis

OBJECTIVE

Galectin-3 (Gal-3) has been suggested as a proinflammatory mediator in rheumatoid arthritis (RA). We aimed to study clinical and pathogenic aspects of Gal-3 in RA.

METHOD

Plasma samples from healthy controls (n = 48) and patients with newly diagnosed, early RA were assayed for soluble Gal-3. In patients with chronic RA (n = 18), Gal-3 was measured in both plasma and synovial fluid. Synovial fluid mononuclear cells were used to purify fibroblast-like synoviocytes (FLSs) and osteoclasts. Monocultures of FLSs and autologous co-cultures of FLSs and peripheral blood mononuclear cells were established and co-incubated with a Gal-3 inhibitor.

RESULTS

Patients with early and chronic RA had persistently increased plasma levels of Gal-3 compared with controls. However, changes in plasma Gal-3 at the level of individuals were associated with long-term disease activity. In seropositive early RA patients, all patients with decreasing plasma Gal-3 from 0 to 3 months had low disease activity after 2 years (p < 0.05). Gal-3 levels in synovial fluid were markedly elevated. In vitro, co-incubation with a Gal-3 inhibitor (GB1107, 10 µM) led to a significant reduction in both interleukin-1β and tumour necrosis factor-α secretion from FLS monocultures (both p < 0.05) and decreased monocyte-derived osteoclastogenesis compared with controls (both p < 0.05).

CONCLUSIONS

Our findings underscore the role of Gal-3 regarding disease activity and tissue destruction in RA. An initial decrease in plasma Gal-3 levels predicted decreased long-term disease activity. Correspondingly, a Gal-3 inhibitor decreased the activity of inflammatory FLSs and osteoclastogenesis in patients with RA.

POS0060 MEASUREMENTS OF COMPLEMENT ACTIVITY SPECIFICALLY THOUGH THE LECTIN -OR THE CLASSICAL PATHWAY IN PATIENTS WITH SLE

Background

In systemic lupus erythematosus (SLE), the complement system (CS) is activated and thought to occur primarily through the classical pathway (CP) [1]. Traditionally, when diagnosing SLE or assessing disease activity, measurement of low C3 or C4 are used as proxies for complement activation [2]. However, measurement of C3 and C4 does not differentiate which complement pathway initiated the activation (i.e., the lectin pathway (LP), the CP, or the alternative pathway) [1, 3].

C1-esterase inhibitor (C1inh) is one of the key regulators of the CS. C1inh is the exclusive inhibitor of the active CP enzymes C1r and C1s [4], and the major inhibitor of active LP enzymes MASP-1 and MASP-2 [5]. A possible way of assessing complement activation through a specific pathway, is by measuring activated enzymes complexed with C1inh in plasma, as these complexes only exist after complement enzyme activation.

Objectives

Our aim was to investigate and unravel LP and CP complement activation in SLE, by measuring the protein complexes MASP1/C1inh (LP specific activation) and C1r/C1inh (CP specific activation). Furthermore, we aimed to investigate whether there is an association between complement activity, disease activity (SLEDAI) and disease manifestations (lupus nephritis (LN)).

Methods

A cross sectional cohort of 150 patients with SLE fulfilling the 1997 ACR classification criteria for SLE were included from the out-patient clinic at the department of Rheumatology, Aarhus University Hospital (AUH), Denmark. Disease manifestations and disease activity using SLEDAI score was assessed at inclusion. Fifty healthy individuals included at the Blood Bank, AUH, were used as controls. Both C1s/C1inh and MASP1/C1inh complexes were measured in all samples using two newly developed sandwich ELISAs (C1s/C1inh: cat# HK399; MASP1/C1inh: Cat#3001, Hycult Biotech, Uden, The Netherlands). EDTA-samples from both SLE patients and controls were measured in duplicates.

Results

When comparing SLE patients to controls, we observed a difference in complement activation through the LP, where a lower mean MASP1/C1inh plasma concentration was observed (p<0.01).

C1s/C1inh concentrations were significantly increased in active SLE patients (SLEDAI >6) when compared to SLE patients with low disease activity (SLEDAI <6, p<0.01) and correlated with SLEDAI score (r=0.285, p<0.01). C1s/C1inh concentrations were increased in SLE patients with active LN compared to non-active LN, however this not statistically significant (p=0.09).

No differences in MASP1/C1inh plasma concentrations were observed between active SLE patients and patients with low disease activity (p=0.11), nor did we observe a significant correlation with disease activity (r=0.12, p=0.13). In active LN, plasma concentrations of MASP1/C1inh were significantly elevated compared to non-active LN (p=0.02).

Conclusion

Our data suggest that the CP and the LP is activated in SLE. CS is generally activated in active SLE disease, whereas activation of the LP might be more specific to particular disease manifestations like LN.

Our findings warrant further research into activation of the specific complement pathways in relation to specific disease manifestations in SLE.

References

[1]Troldborg, A., et al., J Rheumatol, 2018.

[2]Weinstein, A., et al., Curr Rheumatol Rep, 2021.

[3]Atkinson, J.P., Clin Exp Rheumatol, 1989.

[4]Sim, R.B., et al., FEBS Lett, 1979.

[5]Paréj, K., et al., Mol Immunol, 2013.

Figure 1.

Measurements of plasma concentrations of C1r in complex with C1-inhibitor (C1r/C1inh) (a1-a4) and MASP1 in complex with C1-inhibitor (MASP1/C1inh) (b1-b4) in Systemic Lupus Erythematosus (SLE) patients and controls. A1 and b1 show measurements of SLE patients versus controls. A2 and b2 show measurements in SLE patients with active disease (SLEDAI >6) versus low disease activity (SLEDAI<6). A3 and b3 show correlation analysis between measurements and SLEDAI score in SLE patients. A4 and b4 show measurements in SLE patients with active lupus nephritis (LN) versus non-active LN.

Disclosure of Interests

Mads Christian Lamm Larsen: None declared, Anne Troldborg: None declared, Erik Toonen Employee of: ET is an employee of Hycult Biotech, Lisa Hurler: None declared, Zoltán Prohászka: None declared, László Cervenak: None declared, Annette G Hansen: None declared, Steffen Thiel: None declared

POS1348 PATIENTS WITH VEXAS DIAGNOSED IN A DANISH TERTIARY RHEUMATOLOGY SETTING HAVE HIGHLY ELEVATED INFLAMMATORY MARKERS, MACROCYTIC ANEMIA, AND NEGATIVE AUTOIMMUNE BIOMARKERS

Background

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome was described in 2020 with overlapping features of rheumatology and hematology. VEXAS is an autoinflammatory condition caused by somatic mutations in the UBA1 gene at methionine-41.

As patients present with highly variable clinical symptoms [1], their path in the clinical system is often complicated, and characterized by many strenuous examinations and biopsies. It is pivotal, that we familiarize with the VEXAS phenotype and advance identification of patients with VEXAS.

Objectives

We aimed to characterize patients diagnosed with VEXAS in a tertiary rheumatology referral center since December 2020 when the syndrome was described [2].

Methods

All patients were identified and diagnosed at the department of Rheumatology, Aarhus University Hospital (AUH), Denmark. Patients underwent testing for the UBA1 somatic mutations using sanger sequencing at the department of Clinical Immunology, AUH. Sequencing analyzed for somatic variants in/at exon 3 (NM_003334.4: c.118-1G>C, c.121A>C/G, c.122T>C og c.167C>T). Clinical and biochemical data were retrieved from the hospital electronic patient chart.

Continuous variables are presented as median with interquartile range (IQR) and categorical variables as percentages.

Results

A total of 11 male patients with clinical suspicion of VEXAS underwent sequencing. Five men were identified in the period December 2020 to December 2021 with UBA1 somatic mutations. Median age at diagnosis was 84 (75-87). Symptoms debuted on average 22 months (IQR 20-40) before diagnosis. All patients had significantly elevated markers of inflammation: median CRP 297 (196-386), IL-2-receptor, and ferritin and presented with macrocytic anemia. None of the patients were positive for autoimmune biomarkers like ANA, ACPA, MPO-, or PR3-ANCA.

Conclusion

This is, to the best of our knowledge, the first report of Danish patients with the VEXAS syndrome. Patients are males with persistent inflammation, constitutional symptoms, and heterogeneous clinical presentations.

Common features for all patients in this study were highly elevated inflammatory markers, macrocytic anemia, and negative autoimmune biomarkers.

References

[1]Georgin-Lavialle et al. Br J Dermaol. 2021 Oct 1. Online ahead of print

[2]Beck et al. N Engl J Med. 2020 Dec 31;383(27):2628-2638.

Table 1.

Clinical, biochemical characteristics at diagnosis and treatment of Danish VEXAS patients.

Patient 1Patient 2Patient 3Patient 4Patient 5Total n(%) or median (IQR)Clinical characteristicsAge at diagnosis738977848584 (75-87)Time from symptom onset till diagnosis (months)182147302222 (20-40)UBA1 variantc.122 T>C p.Met41Thrc.122 T>Cp.Met41Thrc.122 T>Cp.Met41Thrc.121 A>Cp.Met41Leuc.118-1 G>Cp.(splice)Macrocytic anemia+++++5 (100%)CRP(max, mg/ml)+(335)+(436)+(220)+(172)+ (297)5 (100%) (297 (196-386))Constitutional symptoms*+++++5 (100%)Vasculitis+++-+4 (80%)Chondritis--+-+2 (40%)Ocular inflammation--+--1 (20%)Arthritis+-++-3 (60%)Lung involvement-++++4 (80%)Proteinuria-++-+3 (60%)Thrombosis+--+-2 (40%)BM vacuoles-++NA-2/4 (50%)Biochemical characteristicsANA-----0 (0%)ACPANA---NA0 (0%)PR3 or MPO-ANCA-----0 (0%)

IQR: inter quartile range, BM: bone marrow, ANA: anti-nuclear antibodies, ACPA: anti-citrullinated protein antibody, PR3-ANCA: proteinase-3 anti-cytoplasmatic antibody, MPO: myeloperoxidase, NR: within normal range, NA: not available.*Constitutional symptoms (fever, night sweats, weight loss).

Disclosure of Interests

Mads Nyhuus Bendix Rasch Speakers bureau: Speakers fee in context of alignment meeting in autoinflammatory diseases by Sobi, Fruzsina Szabados: None declared, Jens Magnus Bernth Jensen: None declared, Kirstine Overgaard Nielsen: None declared, Ellen-Margrethe Hauge Speakers bureau: Has received fees for speaking and/or consulting from AbbVie, Sanofi, Sobi, MSD, UCB, Consultant of: Has received fees for speaking and/or consulting from AbbVie, Sanofi, Sobi, MSD, UCB, Grant/research support from: Research funding to Aarhus University Hospital from Novo Nordic Foundation, Danish Rheumatism Association, Danish Regions Medicine Grants, Roche, Novartis;, Anne Troldborg: None declared

POS0261 TIME SINCE LAST RITUXIMAB TREATMENT IS ESSENTIAL FOR DEVELOPING A HUMORAL RESPONSE TO THE COVID-19 MRNA VACCINE IN PATIENTS WITH RHEUMATIC DISEASES

Background

Concerns about Rituximab (RTX) treatment and potentially inadequate vaccine response were aired early in the pandemic, and initial data seem to support this concern (1). So far, studies regarding rheumatic patients and the COVID-19 vaccines have included a relatively small number of patients receiving rituximab.

Objectives

We aimed to investigate if patients with rheumatic diseases treated with RTX raise a serological response towards the COVID-19 mRNA vaccines and to elucidate the influence of time since the last dose RTX before vaccination on this response.

Methods

We included 201 patients followed at the Department of Rheumatology, Aarhus University Hospital. All had been treated with RTX in the period 2017-2021, and had finished a two-dose COVID-19 mRNA vaccination. All patients and 44 blood donors had total antibodies against SARS-CoV2 spike protein measured. Univariate and multivariate logistic regression were used.

Results

Patients were predominantly female (67%) with a median age of 62 years. The most frequent diagnosis was ANCA-associated vasculitis (32%), rheumatoid arthritis (31%), and myositis (14%), and 97% had the Pfizer/Biontic vaccine. Median number of RTX infusions were 5 (IQR 2-8), with a cumulative dose of 4g (2-8), and 72% had received RTX within the last 15 months. Prednisone was used by 43%, followed by methotrexate (25%), hydroxychloroquine (11%) and azathioprine (10%).

We observed a time-dependent increase in antibody response as the interval from the last RTX treatment to vaccination increased (Table 1). Only 17.3% of patients developed a detectable antibody response after receiving their vaccination 6 months or less after their previous RTX treatment (Figure 1). Positive antibody response increased to 66.7% in patients who had RTX 9-12 months before vaccination. Neither cumulative treatment time nor cumulative RTX dose seemed to influence the serological response to the vaccine (Table 1). Thus, even in patients who have received RTX for a substantial time, expanding time-since-last-RTX treatment could prove beneficial for increasing the chance of a serological response. We further found that “months between last Rtx and vaccination”, prednisone and azathioprine treatment were alle negatively associated with antibody response in a multivariate logistic regression analysis(Table 1). All blood donors (100%) had detectable antibodies after vaccination.

Table 1.

Logistic regression analysis with precense of SARS-CoV-2 antibodies after mRNA vaccination as dependent varaible.

UnivariateOR95% CIP-valueSex, female = ref.0.910.50 - 1.670.77Age, years0.980.96 - 1.000.09Diagnosis1.050.99 – 1.130.08Months between last RTX and vaccination1.061.03 - 1.09<0.001Total number of RTX infusions0.960.92 - 1.010.10Total dose of RTX, mg0.970.92 - 1.020.18Time from first to last RTX treatment1.001.00 - 1.000.57No DMARD treatment0.940.50 - 1.780.85Prednisone, dose in mg0.910.85 - 0.990.02Methotrexate1.710.90 - 3.250.10Hydroxychloroquine0.870.35 - 2.190.77Azathioprine0.230.06 - 0.800.02Multivariate modelMonths between last Rtx and vaccination1.081.04 - 1.11<0.001Prednisone treatment, mg0.910.84 - 0.990.03Azathioprine treatment0.100.02 - 0.440.002

All significant variables in the univariate analysis were included in the multivariate model.

Conclusion

In conclusion, patients with rheumatic diseases treated with RTX have a severely impaired serological response towards the COVID-19 mRNA vaccine. This is especially true if the interval between RTX treatment and vaccination is less than 9 months. For the majority of RTX treated patients, the recommended six months since last RTX is insufficient to develop a humoral response to COVID-19 mRNA vaccines. Our data suggest that the current recommendations of a 6 months interval should be revised.

References

[1]Ammitzbøll C, et al. Impaired antibody response to the BNT162b2 mRNA COVID-19 vaccine in patients with Systemic Lupus Erythematosus and Rheumatoid Arthritis. ACR Open Rheumatol. 2021;

Disclosure of Interests

None declared

POS0761 TIME-DEPENDENT ANALYSES OF CLINICAL MANIFESTATIONS OF SYSTEMIC LUPUS ERYTHEMATOSUS IDENTIFY PATIENTS AT HIGH RISK OF INCIDENT PROTEINURIA

Background

Nephritis (LN) in systemic lupus erythematosus (SLE) is still a major determinant of poor prognosis[1].

The vast majority of LN occurs in proximity to the SLE diagnosis[2]. Identification of individuals at high risk, especially early onset SLE, is therefore warranted. Inclusion of risk factors prior to the SLE diagnosis may thus be of importance to enable sufficient risk factor profiling. SLE-patients seem to cluster according to clinical and serological phenotypes suggesting distinct disease trajectories[3-5].

Objectives

To determine if incident proteinuria associated with the debut age of non-renal SLE characteristics.

Methods

Data of SLE patients from six Danish centers were obtained from the Danbio-database from 2017 – 2020. The occurrence and timing of proteinuria was compared with first time onset of any non-renal manifestations as defined by the 1997 American College of Rheumatology Classification Criteria. Cox-regression models were used to identify risk factors for incident proteinuria. Time from first occurring non-renal manifestation to incident proteinuria or censoring defined time at risk. Covariates were eliminated if p >0.01 in a ‘backwards’ manner. After the model reduction process p-values <0.05 were considered statistically significant.

Results

586 SLE patients, mainly white (94%) women (88%), mean age at inclusion of 34.6 years (standard deviation, SD = 0.6 years) and observed for a mean of 14.9 years (SD =0.5 years), were recruited. The cumulative prevalence of proteinuria was 40%. Male gender hazard ratio, HR = 1.35 (range 0.77-2.35), p=0.009, lymphopenia HR = 1.77 (range 1.24-2.52), p=0.005 were associated with incident proteinuria. In contrast, patients with discoid rash had lower risk of incident proteinuria HR 0.42 (range 0.21-0.83), p=0.01. Male patients with lymphopenia had the highest risk of proteinuria with a one-, 5- and 10-year risk of proteinuria ranging from 9-27%, 34-75% and 51-89 %, depending on the age at presentation (debut at 20, 30, 40 or 50 years). The corresponding risk-profiles for women with lymphopenia were 3-9%, 8-34% and 12-58%, respectively, as illustrated in Figure 1.

Conclusion

The occurrences of lymphopenia and discoid rash were oppositely associated with risk of incident proteinuria and the risk effects varied according to gender and patient age at onset of these manifestations. Thus, the risk of proteinuria may not be constant but could vary according to presentation of non-renal manifestations that may call for a differentiated clinical follow-up. Based on these findings, we suggest that the debut age of known prognostic factors, even prior to the SLE diagnosis should be considered when designing prognostic statistical models.

References

[1]Faurschou, M., et al., Prognostic factors in lupus nephritis: diagnostic and therapeutic delay increases the risk of terminal renal failure. J Rheumatol, 2006. 33(8): p. 1563-9.

[2]Hanly, J.G., et al., The frequency and outcome of lupus nephritis: results from an international inception cohort study. Rheumatology (Oxford), 2016. 55(2): p. 252-62.

[3]Diaz-Gallo, L.M., et al., Four Systemic Lupus Erythematosus Subgroups, Defined by Autoantibodies Status, Differ Regarding HLA-DRB1 Genotype Associations and Immunological and Clinical Manifestations. ACR Open Rheumatol, 2022. 4(1): p. 27-39.

[4]Jacobsen, S., et al., A multicentre study of 513 Danish patients with systemic lupus erythematosus. II. Disease mortality and clinical factors of prognostic value. Clin Rheumatol, 1998. 17(6): p. 478-84.

[5]Leffers, H.C.B., et al., Smoking associates with distinct clinical phenotypes in patients with systemic lupus erythematosus: a nationwide Danish cross-sectional study. Lupus Sci Med, 2021. 8(1).

Disclosure of Interests

Martin Andersen Employee of: Novo Nordisk A/S: 2010-2014, Anders Stockmarr: None declared, Henrik Leffers: None declared, Anne Troldborg: None declared, Anne Voss: None declared, Salome Kristensen: None declared, Bent Deleuran: None declared, Lene Dreyer Speakers bureau: Speakers bureau: Eli Lilly, Galderma and Janssen, Grant/research support from: Grant from BMS outside the present work, Laura Johnsen: None declared, Ada Colic: None declared, Søren Jacobsen: None declared

POS0263 RE-VACCINATION COMPARED TO BOOSTER COVID-19 mRNA VACCINATION SIGNIFICANTLY INCREASES THE SEROLOGICAL RESPONSE IN RITUXIMAB-TREATED PATIENTS WITH INFLAMMATORY RHEUMATIC DISEASES WITHOUT A PRIMARY DETECTABLE SEROLOGICAL COVID-19 VACCINE RESPONSE

Background

Reports of an impaired humoral response after COVID-19 vaccination in patients treated with rituximab (RTX) have raised particular concern for patients with inflammatory rheumatic diseases (IRD) receiving RTX (1). This calls for strategies to enhance a humoral response in RTX-treated patients. At present, there is no data on whether it is best to increase the humoral response with a third vaccine dose (a booster) or with a third and fourth dose (re-vaccination).

Objectives

In IRD patients treated with RTX, without a detectable humoral response after the first vaccination course (two shots), we aimed to investigate the difference of either a booster vaccine (dose 3) or a new re-vaccination course (dose 3 + 4) on the serological response of the COVID-19 mRNA vaccines.

Methods

We included 84 patients with IRD treated with RTX, all without measurable total SARS-CoV-2 antibodies after a full primary COVID-19 vaccination course (2 doses three weeks apart). All patients were offered a new re-vaccination course with the mRNA vaccine not used primarily (Pfizer/Biontec or Moderna). A small number of patients declined the revaccination, and recieved a booster with the mRNA vaccine used initially. Serum total antibodies were measured before and six weeks after the last dose against recombinant SARS-CoV-2 spike S1 protein (VITROS). In addition, CD19+ B-cells were measured at inclussion.

Results

Patient characteristics are in Table 1. The median age was 64 years; 68% were female with a disease duration of 5 years. Sixty-nine out of 84 were re-vaccinated (3 + 4 dose). Details previous exposure to RTX are given in Table 1. CD19+ B-cells were measurable in 12/81 at inclusion.

Table 1.

Patient Characteristics

Booster, n=15Revaccination, n=69Age, years median (IQR)60 (45 - 69)65 (54 - 70)Female47%72%Disease duration, years (IQR)5 (2-8)6(2 - 13) ANCA-vasculitis47 %45 % Rheumatoid Arthritis47 %17 % Poly- Dermatomyositis6 %19 % SLE, Scleroderma, other diagnoses-19 %No DMARD treatment27 %35 %Prednisone33 %46 %Methotrexate40 %16 %Azathioprine7 %12 %Mycophenolate7 %7 %Other20 %9 %Rituximab treatment, (IQR) Months from last RTX to vaccination3.9 (1.3 - 9.3)5.4 (4.2 - 7.3) Number of infusions6 (4 - 8)7 (5 - 12) Cummulativ total dose, gram4 (2.5 - 7.5)6 (3.5 - 10) Total treatment time with RTX, months15 (9 - 54)27 (13 - 63)Patients with measurable CD19+ B-cells in peripheral blood at the time of booster or re-vaccination (positive/total)3/149/67

We found a combined seroconversion rate of 33% six weeks after the last shot. There was no statistical difference between the booster (38,5%) and the re-vaccination group (32,3%), p=0.67 (Pearson’s chi-squared). IRD patients with a humoral response in the re-vaccination group had significantly higher levels of total SARS-CoV-2 antibodies (median(IQR) 306(49-464) AU/ml) compared to the booster group (14(4-15) AU/ml) p=0.02, Figure 1A. In multiple logistic regression model, we found that levels of CD19+ B-cells were the only variable able to predict a humoral response, Figure 1B. However, only 39% of the patients with a humoral response to vaccination had measurable CD19+ B-cells before vaccination. We found no effect of age, sex, diagnosis, treatment, and RTX exposure on the chance of seroconversion in multiple logistic regression models when corrected for CD19+ B-cells.

Figure 1.

Conclusion

We found that re-vaccination (dose 3 + 4) with COVID-19 mRNA vaccines favored a high humoral response in patients with IRD treated with RTX, who did not have a detectable humoral response after the first two vaccine doses, compared to a booster shot (dose 3). A detectable humoral response after re-vaccination was seen in more than half of the patients with no measurable CD19+ B-cells before vaccination. Presence of circulating CD19+ B-cells are a significant predictor of humoral response to mRNA COVID-19 vaccination.

References

[1]Ammitzbøll et al. ACR Open Rheum. 2021 Sep;3(9):622-628. doi: 10.1002/acr2.11299.

Acknowledgements

The Danish Rheumatism Association - Gigtforeningen for funding the study.

Disclosure of Interests

None declared

POS1198 VACCINATION AGAINST COVID-19 SHOULD BE ENCOURAGED IN PATIENTS WITH RHEUMATIC DISEASE, AS MOST PATIENTS DEVELOP A SEROLOGICAL RESPONSE AGAINST THE VACCINE AND VACCINATION REDUCES SELF-IMPOSED ISOLATION AND SHIELDING BEHAVIOR

Background

Vaccine trials of the SARS-CoV-2 mRNA vaccines were encouraging but excluded most patients with rheumatic diseases (RD) and patients treated with immunosuppressive therapy. However, reports of a more severe COVID-19 disease course in patients with RDs prompted strategies for expediting vaccination of RD patients in most countries.

In addition to the impact experienced by most people of the pandemic, patients with RDs were adversely impacted by the potential risk of severe COVID-19 due to their disease and immunosuppressive treatment. Fear of COVID-19 led to disproportionate anxiety, self-isolation, and shielding behavior for many RD patients at the beginning of the pandemic.

Objectives

We investigated antibody levels in serum against SARS-CoV-2 after a two-dose vaccination with an mRNA vaccine in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Further, we examined the association between reactogenicity and immunogenicity and how vaccination influenced patient behavior concerning fear of COVID-19 and shielding.

Methods

Patients with SLE or RA from the COPANARD (Corona PANdemic Autoimmune Rheumatic Disease)1 cohort received two doses of an mRNA vaccine between January and August 2021 and had total antibodies against SARS-CoV-2 measured before vaccination and 2 and 9 weeks after the second vaccination. In addition, patients answered an electronic questionnaire before and eight weeks after vaccination concerning behavior, anxiety, and symptoms of depression (PHQ-9).

Results

Three-hundred-and-three patients and 44 blood donors (healthy controls) were included. Significantly fewer patients (90%) had measurable antibodies against SARS-CoV-2 compared to blood donors (100%) after the second vaccination (p<0.001) (Figure 1). Treatment with Rituximab was the strongest predictor of unfavorable vaccine response, as only 27% were seropositive after vaccination. We found a negative effect of prednisone and methotrexate but no effect of age, comorbidity, or pausing medication on seroconversion. Patients experienced significant improvement after vaccination in 10 out of 12 questions regarding behavior and fear of COVID-19, but no change was observed in symptoms of depression (p=0.62) or anxiety (p=0.46).

Figure 1.

Total antibody response against SARS-CoV-2 after two mRNA vaccines. Antibody response against mRNA COVID-19 vaccine pre-vaccination, 1 and 9 weeks after in patients with rheumatic diseases and 5-6 weeks after vaccination in blood donors. (A) Percentage with measurable SARS-CoV-2 antibody results after vaccination. (B) Levels of SARS-CoV-2 antibodies in serum.

Conclusion

The majority of patients with SLE or RA had a measurable serological response to the COVID-19 mRNA vaccine after two doses. Treatment with Rituximab was the strongest predictor of no seroconversion.

Our findings warrant encouragement of vaccination against COVID-19 for patients with RD, as most patients benefits with both a serological immune response and reduced isolation and shielding behavior.

References

[1]Ammitzbøll C, Andersen JB, Vils SR, Mistegaard CE, Mikkelsen S, Erikstrup C, Thomsen MK, Hauge EM, Troldborg A. Arthritis Care Res (Hoboken). 2021 May 31:10.1002/acr.24716. doi: 10.1002/acr.24716. Online ahead of print.

Disclosure of Interests

None declared

AB0457 IMPROVED PREGNANCY OUTCOMES IN WOMEN WITH SYSTEMIC LUPUS ERYTHEMATOSUS: A RETROSPECTIVE STUDY OF PREGNANCIES FROM A SINGLE CENTER IN DENMARK FROM 2010-2020 COMPARED WITH THE PERIOD 1990-2010

Background

Over the past decades, the approach to follow and treat pregnant SLE patients has changed. Today it is recommended that pregnant patients are monitored closely in a multi-professional team throughout pregnancy (1). The importance of low disease activity before pregnancy and continued treatment during pregnancy has been established (2). Even though many improvements in the management of SLE pregnancies has been made, there is still a high risk of adverse pregnancy outcome (APO).

Objectives

We aimed to evaluate APO in a Danish SLE cohort followed from 2010-2020 and compare the results with a previous study cohort from the same referral area followed from 1990-2010 (3).

Methods

This retrospective cohort study used the local patient registry to identify pregnancies in SLE patients followed at the Department of Rheumatology, Aarhus University Hospital, Denmark from January 2010 to October 2020. All patients were followed regularly and fulfilled at least four of the 1997 American College of Rheumatology (ACR) criteria for SLE classification. Data included demographic, clinical, and laboratory data. Demographics included ethnicity, smoking habits, body mass index (BMI), and concomitant APS (recognized before pregnancy). Data were compared with data from a previous study (1990-2010) from the same department.

Results

In total, 66 pregnancies were registered in 41 women. APO occurred in 65 % of pregnancies. Forty-seven pregnancies resulted in a live birth, while 15 ended in miscarriage. Compared to the 1990-2010 cohort, a reduction in preterm deliveries (7.58 % vs. 17.9 %), acute caesarean (6.1 % vs. 15.5 %), and higher average birth weight (3045 g vs. 2870 g) were found (Table 1). Further, we observed more pregnancies and live births per year (Figure 1). A change in the approach to treatment was found, i.e., significantly more patients were treated with hydroxychloroquine (73 %) compared to the 1990-2010 cohort (6 %).

Figure 1.

Pregnancy outcome. Average number of pregnancies and live birth per year in the Aarhus SLE cohort in the period 1990-2010 compared with 2010-2020

Table 1.

Maternal and fetal/neonatal adverse pregnancy outcomes in our study population (2010-2020) compared with previous study at Aarhus University Hospital (1990-2010).

1990-2010 n=842010-2020 n=66p-valuePre-eclampsia/eclampsia, n (%)7 (8.3)8 (12.1)0.59HELLP syndrome, n (%)4 (4.8)0-Gestational hypertension, n (%)20 (23.8)9 (13.6)0.05Preterm deliveries (<37th gestational week), n (%)15 (17.9)5 (7.58)0.07Acute caesarean delivery, n (%)13 (15.5)4 (6.1)0.07Elective caesarean delivery, n (%)11 (13.1)8 (12.1)-Total caesarean delivery, n (%)24 (28.6)12 (18.2)-Total fetal loss, n (%)22 (26.2)19 (28.8)0.72Spontaneous abortion <22 weeks, n (%)18 (21.4)15 (22.7)0.85Therapeutic abortion3 (3.6)4 (6.1)0.47Still birth1 (1.2)0-Fetal death after birth2 (2.4)0-Birth weight, mean ± SD g2870 (SD,NA)3045 ± 611-IUGR10 (11.9)NA-SGANA12 (18.18)-Congenital heart block, n (%)1 (1.2)0-Neonatal Lupus Syndrome, n (%)2 (2.4)0-

Conclusion

Improvements in the frequency of APO were found in 2010-2020 compared with 1990-2010. However, even though a specialized multi-professional team closely follows pregnant women with SLE, pregnancy in SLE still carries a high risk of APO.

References

[1]Andreoli L et al. EULAR recommendations for women’s health and the management of family planning, assisted reproduction, pregnancy and menopause in patients with systemic lupus erythematosus and/or antiphospholipid syndrome. Ann Rheum Dis. 2017;76(3):476–85.

[2]Lateef A, Petri M. Management of pregnancy in systemic lupus erythematosus. Vol. 8, Nature Reviews Rheumatology. Nature Publishing Group; 2012. p. 710–8.

[3]Jakobsen IM et al. Maternal and foetal outcomes in pregnant systemic lupus erythematosus patients: an incident cohort from a stable referral population followed during 1990-2010. Scand J Rheumatol. 2015;44(5):377–84.

Disclosure of Interests

None declared

AB0006 ESTABLISHED RISK LOCI FOR SYSTEMIC LUPUS ERYTHEMATOSUS AT NCF2, STAT4, TNPO3, IRF5 AND ITGAM ASSOCIATE WITH DISTINCT CLINICAL MANIFESTATIONS: A DANISH GENOME-WIDE ASSOCIATION STUDY

Background

Systemic lupus erythematosus (SLE) has been associated with more than 100 genetic loci. This parallels positively to the clinical diversity that is reflected by the classification of SLE.

Objectives

We aimed to investigate associations between disease manifestations of SLE and risk gene variants relevant to Danish subjects of European ancestry.

Methods

We included 427 SLE patients of European ancestry similar to previous reports.[1] We also included 89,699 controls from the Danish Blood Donor Study Genomic Cohort. SLE risk loci in this population were identified by genome-wide association methodology and hereafter correlated to cumulative occurrence of SLE classification items.

Results

Fourteen variants mapped to the following genes: NCF2, STAT4, TNPO3/TPI1P2, IRF5, and ITGAM, were significantly associated (p<5E-8) with SLE.

The five lead variants were associated (p<0.05) with the following manifestations; NCF2: proteinuria and anti-phospholipid antibodies, STAT4: arthritis, serositis, neurologic disorder, lymphopenia, and anti-Smith antibodies, IRF5: seizures and proteinuria, TNPO3: proteinuria, and ITGAM: photosensitivity (Table 2).

Conclusion

Our findings support the future use of select, relevant genetic markers in predicting various SLE phenotypes.

References

[1]Leffers HCB, Troldborg A, Voss A, et al. Smoking associates with distinct clinical phenotypes in patients with systemic lupus erythematosus: a nationwide Danish cross-sectional study. Lupus Sci Med 2021;8(1).

Table 1.

Associations between five SLE risk loci and specific disease manifestations in 427 Danish patients with SLE*.

NCF2STAT4IRF5TNPO3ITGAMrs17849502_Trs7574865_Trs4728142_Ars13239597_Ars11860650_TN (%)Malar rash233 (55%)1.28 (0.84-1.96)0.83 (0.62-1.11)1.01 (0.74-1.38)1.44 (0.97-2.12)1.14 (0.80-1.61)Discoid rash46 (11%)1.49 (0.81-2.73)0.90 (0.56-1.45)1.01 (0.62-1.66)1.16 (0.63-2.12)0.76 (0.42-1.41)Photosensitivity219 (51%)0.96 (0.63-1.46)1.09 (0.81-1.47)0.98 (0.71-1.34)0.84 (0.57-1.25)0.67 (0.47-0.97)Oral ulcers132 (31%)0.96 (0.61-1.50)0.90 (0.65-1.23)0.83 (0.60-1.16)1.30 (0.87-1.96)1.43 (0.99-2.05)Non-erosive Arthritis342 (80%)0.84 (0.52-1.37)1.49 (1.02-2.18)0.93 (0.63-1.36)1.04 (0.64-1.68)1.16 (0.74-1.80)Serositis-Pleuritis124 (29%)0.63 (0.38-1.05)1.38 (1.01-1.89)1.22 (0.87-1.72)0.85 (0.56-1.29)0.84 (0.57-1.24)-Pericarditis72 (17%)0.75 (0.41-1.40)1.35 (0.93-1.96)1.05 (0.70-1.58)1.15 (0.70-1.89)1.09 (0.70-1.72)Persistent proteinuria158 (37%)1.63 (1.07-2.49)1.08 (0.80-1.46)0.68 (0.49-0.94)1.74 (1.16-2.61)1.09 (0.76-1.57)Neurologic disorder-Seizures23 (5%)1.58 (0.75-3.35)1.49 (0.80-2.76)2.10 (1.04-4.25)0.61 (0.26-1.44)0.93 (0.42-2.06)-Psychosis8 (2%)0.76 (0.097-5.87)2.77 (0.94-8.15)0.35 (0.10-1.23)0 (0)2.96 (0.85-10.3)Haematologic disorder-Haemolytic anaemia38 (9%)0.78 (0.34-1.76)1.37 (0.85-2.22)0.75 (0.44-1.29)1.11 (0.57-2.19)1.24 (0.70-2.20)-Leukopenia130 (30%)1.04 (0.67-1.61)1.19 (0.87-1.63)1.00 (0.72-1.39)0.90 (0.60-1.37)0.94 (0.64-1.37)-Lymphopenia228 (53%)0.95 (0.63-1.44)1.35 (1.01-1.81)0.95 (0.70-1.29)1.16 (0.79-1.70)1.09 (0.77-1.54)-Thrombocytopenia102 (24%)1.42 (0.91-2.22)0.84 (0.60-1.18)0.83 (0.58-1.18)1.35 (0.86-2.11)0.91 (0.60-1.37)Immunologic disorder-anti-DNA ab.330 (77%)0.69 (0.44-1.09)1.02 (0.72-1.44)0.94 (0.65-1.35)0.97 (0.62-1.53)1.08 (0.71-1.65)-anti-Smith ab.44 (10%)1.44 (0.79-2.64)1.58 (1.00-2.49)1.23 (0.73-2.07)1.47 (0.80-2.69)1.07 (0.61-1.84)-anti-phospholipid ab.183 (43%)1.63 (1.07-2.49)1.05 (0.79-1.41)0.84 (0.61-1.14)1.14 (0.77-1.68)1.14 (0.80-1.62)

* Logistic regression models for each manifestation included all five lead variants (multivariate) and were adjusted for age and sex

Disclosure of Interests

Henrik Leffers: None declared, David Westergaard: None declared, Saedis Saevarsdottir: None declared, Ingileif Jonsdottir: None declared, Ole Birger Pedersen: None declared, Anne Troldborg: None declared, Anne Voss: None declared, Salome Kristensen: None declared, Jesper Lindhardsen: None declared, Prabhat Kumar: None declared, Asta Linauskas: None declared, Lars Juul: None declared, Niels Steen Krogh: None declared, Bent Deleuran: None declared, Lene Dreyer Speakers bureau: Speakers bureau: Eli Lilly, Galderma and Janssen, Grant/research support from: from BMS outside the present work, Michael Schwinn: None declared, Lise wegner Thørner: None declared, Lotte Hindhede: None declared, Christian Erikstrup: None declared, Henrik Ullum: None declared, Søren Brunak Shareholder of: SB has ownerships in Intomics A/S, Hoba Therapeutics Aps, Novo Nordisk A/S, Lundbeck A/S, Kari Stefansson: None declared, Karina Banasik: None declared, Søren Jacobsen: None declared

POS0059 COMPLEMENT PROTEINS ARE ELEVATED IN PATIENTS WITH axSpA COMPARED WITH RELEVANT CONTROLS OF PATIENTS WITH LOW BACK PAIN AND SpA-FEATURES WITHOUT AXSPA

Background

Axial spondyloarthritis (axSpA) is associated with a certain genetic predisposition, i.e., with the presence of human leukocyte antigen (HLA)-B27. However, the pathogenesis remains largely unexplained. Animal models of ankylosing spondylitis have shown inhibition of complement to be beneficial in terms of limiting structural damage (1). The lectin pathway of complement activation serves as a key component of the innate immune system and plays a pivotal role in both homeostasis and development. The influence of complement in axSpA is mainly unexplored. We have, however, previously reported elevated plasma levels of the lectin pathway proteins L-ficolin and H-ficolin in patients with axSpA compared with blood donors (2).

Objectives

Our aim was to investigate plasma levels of lectin pathway proteins in a clinical cohort of patients with axSpA and compare them to relevant controls that we often experience significant challenges in differentiating from axSpA.

Methods

Plasma samples were obtained from individuals in a cohort of patients suffering from low back pain (LBP) including: 1) 23 patients with axSpA, 2) 55 patients without axSpA experiencing SpA-features/symptoms, and 3) 64 patients with nonspecific LBP without SpA-features or MRI findings suggestive of axSpA. Diagnosis of axSpA was based on multidisciplinary team conference consensus after 3.5 years of follow-up (3). Plasma levels of 10 lectin pathway proteins (MBL, CL-L1, H-ficolin, L-ficolin, M-ficolin, MASP-1, MASP-2, MASP-3, MAp44, and MAp19) were measured by immunoassays developed in-house.

Results

Patient characteristics are shown in Table 1. Plasma levels of lectin pathway proteins L-ficolin, M-ficolin and CL-L1 differed significantly in the patient groups (p ≤ 0.03). L-ficolin and M-ficolin were elevated in axSpA-patients compared with patients with SpA-features without axSpA and nonspecific LBP patients (Figure 1). CL-L1 was elevated in axSpA-patients and patients with SpA-features without axSpA compared with nonspecific LBP patients (Figure 1). No significant differences were observed for MBL, H-ficolin, MASP-1, MASP-2, MASP-3, MAp44, and MAp19. L-ficolin levels correlated with CRP in axSpA-patients (Spearman’s rho=0.58 p=0.004). M-ficolin levels correlated weakly with CRP in nonspecific LBP patients (Spearman’s rho=0.36 p=0.003). Lectin pathway protein levels did not correlate with disease activity (ASDAS).

Table 1.

Patient characteristics

axSpA (n=23)Not axSpA (n=55)Non-specific low back pain (n=64)p-valueMedian age, years (range)32 (19-40)33 (19-41)32 (18-39)0.75aMales, n (%)10 (43)37 (67)26 (41)0.01bHLA-B27 positive, n (%)17 (74)11 (20)5 (8)0.00bInflammatory back pain, n (%)18 (78)28 (51)0.03cGood response to NSAID14 (61)17 (31)0.01cSacroiliitiis on MRI acc. ASAS, n (%)22 (96)45 (82)0.11cElevated CRP, n (%)3 (13)7 (13)0.97ASDAS (range)2.5 (1.2-3.7)2.3 (0.8-3.8)0.52d

a compared by Kruskal-Wallis test.

b all three groups compared by Chi2 test.

c compared by Chi2 test.

d compared by Mann Whitney U test.

Figure 1.

Plasma levels of L-ficolin, M-ficolin and CL-L1.

Conclusion

L-ficolin and M-ficolin are increased in patients with axSpA when compared with relevant control cohorts of patients with LBP or with SpA-features without axSpA. Our findings support a potential pathogenic role for complement in axSpA, however, further studies are needed to elucidate the diagnostic potential of the specific complement proteins.

References

[1]Yang, C. et al. Inhibition of complement retards ankylosing spondylitis progression. Sci. Rep. (2016) doi:10.1038/srep34643.

[2]Troldborg, A. et al. Plasma levels of H- and L-ficolin are increased in axial spondyloarthritis: improvement of disease identification. Clin. Exp. Immunol. (2020) doi:10.1111/cei.13374.

[3]Kiil, R. M. et al. Diagnosing axSpA by multidiciplinary team conference at 3.5 years’ follow-up in a cohort of patients with disease features according to the ASAS criteria. Scand. J. Rheumatol. (2021) doi:10.1080/03009742.2021.1933584.

Disclosure of Interests

None declared

POS1171 THE COVID-19 PANDEMIC PROMPTS ISOLATION AND BEHAVIORAL CHANGES IN PATIENTS WITH CHRONIC RHEUMATIC DISEASES LEADING TO REDUCED PHYSICAL ACTIVITY, INCREASED PAIN, DISEASE ACTIVITY, AND LOW SEROPREVALENCE OF SARS-CoV2 ANTIBODIES

Background:

The coronavirus disease 2019 (COVID-19) pandemic has complicated the management of chronic rheumatic diseases (CRD). Patients with CRDs are immunocompromised and generally prone to infection. The fear of COVID-19 and the degree of the self-imposed shielding strategy implemented by many patients introduced new challenges for the patients. Although recommendations have been developed to manage patients with CRDs by, i.e., EULAR, strong evidence is still lacking to guide treatment decisions.

Objectives:

This study aimed to assess the seroprevalence of SARS-CoV-2 antibodies in patients with CRDs and healthy controls during the first wave of the pandemic. We further evaluated the effect of the pandemic on patient behavior regarding medication, exercise, pain, and experienced disease activity. Finally, we investigated the self-perceived consequences of the pandemic and lock-down on anxiety and depression in patients with CRDs compared with healthy controls.

Methods:

More than 900 participants were included in the study: 405 patients with rheumatoid arthritis or systemic lupus erythematosus and 513 blood donors. All participants had SARS-CoV-2 antibodies measured (Wantai SARS-CoV-2 total antibody ELISA; sensitivity 96.7%, specificity 99.5%) and answered a questionnaire concerning behavior, anxiety, and symptoms of depression (PHQ-9). The participants with CRD were further asked about physical activity, adherence to medication, and disease-related symptoms.

Results:

CRD patients had a sixfold lower seroprevalence of SARS-CoV-2 antibodies compared to controls (p=0.03) (Figure 1). Almost 60% of patients were unable to exercise as usual, leading to increased pain in 34%, and experience of increased disease activity in 27%. Approximately 10% of patients reduced or discontinued their immunosuppressive treatments at their own initiative. Symptoms of moderate depression were present in 19% of patients compared to 6,8% of controls (p<0.001).

Figure 1.

Presence of SARS-CoV-19 antibodies in chronic rheumatic disease patients (1/365, 0.3%) and controls (blood donors (10/513, 1.9%), *(p=0.03).

Conclusion:

Low seroprevalence in patients with CRDs indicates successful mitigation of exposure to SARS-CoV-2. However, this appears to occur at the expense of physical activity and adherence to immunosuppressive treatment. Our results raise an important concern regarding the consequences of isolation for patients with CRDs. The result of physical isolation is a risk of severe mental health issues, physical inactivity, self-medication, increased pain, and increased disease activity. The long-term consequences of recommendations for patients with CRDs should be taken into account when tackling the continuing pandemic.

Table 1.Patient characteristicsCRD cohortBlood donorsPatients included, n405 (206 SLE, 199 RA)513Disease duration, years (IQR)12.9(7.0-23.0)Age, years (IQR)56.9(43.6-66.9)47(33-57)BMI, kg/m2 (IQR)25.0(22.1-28.6)25.5(23.1-28.4)Charlson Comorbidity Index, score (IQR)2(1-4)Behavioral and mental changes due to the risk of COVID-19CRD cohortBlood donorsp-valueWashes hands more often (%)91.691.40.92Coughing or sneezing in the elbow (%)83.084.00.67Wearing face mask (%)5.02.40.001Restricts the use of public transport (%)47.432.9<0.001Avoid places where many people are gathered (%)80.770.0<0.001Stay at home (%)51.635.3<0.001Symptoms of moderate depression, PHQ-9 >=10, (%)19.016.75<0.001Pandemic effect on training, pain and disease activityCRD cohortHave you been able to exercise as usually, yes (%)41.4Have you been less physically active due to COVID-19, yes (%)44.7Has the degree of physical activity increased the pain from your rheumatological disease? yes(%)33.9Have you experienced increased disease activity during COVID-19? yes(%)26.9

Interquartile range (IQR), Patient Health Questionnaire-9 (PHQ-9),

Acknowledgements:

This study was funded by the Danish Rheumatism Association. We are thankful for the help with creation of the questionnaire by patient research partners Lene Mandrup Thomsen, Nanna Bacci Hartz, Lene Lau og Jeanette Andersen.

Disclosure of Interests:

Christian Ammitzbøll: None declared, Jakob Bøgh Andersen: None declared, Signe Risbøl Vils: None declared, Clara Mistegaard Jørgensen: None declared, Ellen-Margrethe Hauge Speakers bureau: AbbVie, Sanofi, Sobi, MSD, UCB, Grant/research support from: Roche, Norvartis, Christian Erikstrup: None declared, Susan Mikkelsen: None declared, Marianne Kragh Thomsen: None declared, Anne Troldborg: None declared.

Plasma levels of H- and L-ficolin are increased in axial spondyloarthritis: improvement of disease identification

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that primarily affects the axial skeleton. A predominance of innate versus adaptive immune responses have been reported in axSpA, indicating a prominent autoinflammatory component of the disease. Little is known about the lectin pathway proteins (LPPs) of the complement system in relation to axSpA. We have investigated LPPs in patients with axSpA and control individuals. Plasma samples were obtained from a cross-sectional cohort of 120 patients with a clinical diagnosis of axSpA and from 144 age- and gender-matched controls. The plasma concentrations of 11 LPPs were measured, using sandwich-type time-resolved immunofluorometric assays in patients and controls, and related to clinical diagnosis and disease activity. Three LPPs [H-ficolin (ficolin-3), L-ficolin (ficolin-2) and collectin liver 1 (CL-L1)] were significantly higher in axSpA patients than in controls (P < 0·0001) and one LPP, collectin kidney 1 (CL-K1), was significantly lower (P < 0·0001). Further, combining H- or L-ficolin concentrations above the 75th percentile of the respective H- or L-ficolin concentration measured in controls with human leucocyte antigen (HLA)-B27 positivity yielded axSpA diagnostic specificities of 99/99% and positive likelihood ratios of 68/62, respectively. H-ficolin and L-ficolin plasma concentrations were found to be elevated in axSpA patients regardless of time since diagnosis. H-ficolin and L-ficolin may represent diagnostic biomarkers for patients with axSpA and should be further evaluated. Our results showed no association between disease activity and the measured LPP concentrations. This result might be due to the cross-sectional design, and should be further investigated.

Changes in the Lectin Pathway Following Intracerebral or Spontaneous Subarachnoid Hemorrhage

Previous research indicates that the complement system is activated after occurrence of intracerebral hemorrhage (ICH) and spontaneous subarachnoid hemorrhage (SAH). The role of the lectin pathway (LP) of the complement system in this activation has only scarcely been investigated. The aim of this study was to determine the plasma concentration of the LP proteins in patients with ICH or SAH at admission compared to healthy individuals. Secondly, ICH and SAH patients were followed during the initial 24 h of disease, to investigate changes in LP protein concentrations during the critical acute phase. This prospective, observational study included 30 ICH and 33 SAH patients. EDTA plasma samples were collected at admission, 6 and 24 h after symptom onset. Time-resolved immuno-flourometric assays (TRIFMA) were used to measure all proteins of the LP in patient samples and in samples from age- and gender-matched healthy individuals. Compared to healthy individuals, ICH and SAH patients had increased levels of H-ficolin (p = 0.04, p = 0.03), M-ficolin (both p < 0.0001), and MAp44 (both p = 0.01) at admission. M-ficolin, H-ficolin, CL-L1, MASP-1, MASP-3, and MAp44 decreased significantly in both ICH and SAH patients during the initial 24 h after symptom onset. In conclusion, we observed significant differences in lectin pathway protein concentrations between patients with ICH or SAH and healthy individuals. Significant dynamics in lectin pathway protein levels were demonstrated during the initial 24 h after symptom onset. This indicates a potential role of the LP proteins during the acute phase of SAH and ICH.

The complement lectin pathway after cardiac arrest

The lectin pathway (LP) of the complement system may initiate inflammatory reactions when body tissue is altered. We aimed to investigate the levels of the LP proteins in out-of-hospital cardiac arrest patients, and to compare these with healthy individuals. Furthermore, we aimed to clarify whether the duration of targeted temperature management influenced LP protein levels, and we further examined whether LP proteins were associated with 30-day mortality. We included 82 patients resuscitated from out-of-hospital cardiac arrest. The patients were randomly assigned to 24 or 48 hours of targeted temperature management at 33 ± 1°C. Blood samples were obtained 22, 46 and 70 hours after target temperature was reached. Levels of the LP proteins (mannan-binding lectin [MBL], M-ficolin, H-ficolin, collectin liver 1 [CL-L1], MBL-associated serine protease 1 [MASP-1], MASP-2, MASP-3 and MBL-associated protein of 44 kDa [MAp44]) were measured using time-resolved immunofluorometric assays. Data from 82 gender matched healthy individuals were used for comparison. Levels of CL-L1, MASP-1, MASP-2 and MAp44 were significantly higher, whereas M-ficolin levels were significantly lower in cardiac arrest patients compared with healthy individuals. MASP-2, MASP-3 and M-ficolin levels changed significantly when comparing 24 and 48 hours of targeted temperature management. The LP protein levels were not different between 30-day survivors and non-survivors after cardiac arrest. The differences in LP protein levels between patients and healthy individuals may indicate that cardiac arrest patients have an activated LP. Overall, the LP protein levels were not influenced by the duration of targeted temperature management, and the levels were not associated with 30-day mortality.

Collectin liver 1 and collectin kidney 1 and other complement-associated pattern recognition molecules in systemic lupus erythematosus

The objective of this study was to explore the involvement of collectin liver 1 (CL-L1) and collectin kidney 1 (CL-K1) and other pattern recognition molecules (PRMs) of the lectin pathway of the complement system in a cross-sectional cohort of systemic lupus erythematosus (SLE) patients. Concentrations in plasma of CL-L1, CL-K1, mannan-binding lectin (MBL), M-ficolin, H-ficolin and L-ficolin were determined in 58 patients with SLE and 65 healthy controls using time-resolved immunoflourometric assays. The SLE patients' demographic, diagnostic, clinical and biochemical data and collection of plasma samples were performed prospectively during 4 months. CL-L1, CL-K1 and M-ficolin plasma concentrations were lower in SLE patients than healthy controls (P-values < 0.001, 0.033 and < 0.001, respectively). H-ficolin concentration was higher in SLE patients (P < 0.0001). CL-L1 and CL-K1 plasma concentrations in the individuals correlated in both patients and controls. Patients with low complement component 3 (C3) demonstrated a negative correlation between C3 and CL-L1 and CL-K1 (P = 0.022 and 0.031, respectively). Patients positive for anti-dsDNA antibodies had lower levels of MBL in plasma than patients negative for anti-dsDNA antibodies (P = 0.02). In a cross-sectional cohort of SLE patients, we found differences in the plasma concentrations of CL-L1, CL-K1, M-ficolin and H-ficolin compared to a group of healthy controls. Alterations in plasma concentrations of the PRMs of the lectin pathway in SLE patients and associations to key elements of the disease support the hypothesis that the lectin pathway plays a role in the pathogenesis of SLE.