Low disease activity of microscopic polyangiitis in patients with anti-myosin light chain 6 antibody that disrupts actin rearrangement necessary for neutrophil extracellular trap formation

doi:10.21203/rs.3.rs-2083196/v1

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Research Article

Low disease activity of microscopic polyangiitis in patients with anti-myosin light chain 6 antibody that disrupts actin rearrangement necessary for neutrophil extracellular trap formation

https://doi.org/10.21203/rs.3.rs-2083196/v1

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Background

Neutrophil extracellular traps (NETs) are critically involved in microscopic polyangiitis (MPA) pathogenesis, and some patients with MPA possess anti-NET antibody (ANETA). Anti-myosin light chain 6 (MYL6) antibody is an ANETA that affects NETs. This study aimed to determine the significance of anti-MYL6 antibody in MPA.

Methods

The influence of anti-MYL6 antibody on NET formation and actin rearrangement necessary for NET formation was assessed by fluorescent staining. An enzyme-linked immunosorbent assay was established to detect serum anti-MYL6 antibody, and the prevalence of this antibody in MPA was determined. Furthermore, the disease activity and response to remission-induction therapy of MPA were compared between anti-MYL6 antibody-positive and -negative MPA patients.

Results

Anti-MYL6 antibody disrupted G-actin polymerization into F-actin, suppressing phorbol 12-myristate 13-acetate-induced NET formation. Serum anti-MYL6 antibody was detected in 7 of 59 patients with MPA. The Birmingham vasculitis activity score (BVAS) of anti-MYL6 antibody-positive MPA patients was significantly lower than anti-MYL6 antibody-negative MPA patients. Among the nine BVAS evaluation items, the cutaneous, cardiovascular, and nervous system scores of anti-MYL6 antibody-positive MPA patients were significantly lower than anti-MYL6 antibody-negative MPA patients, although other items, including renal and chest scores, were equivalent between the two groups. The proportion of patients with remission 6 months after initiation of remission-induction therapy in anti-MYL6 antibody-positive MPA patients was significantly higher than in anti-MYL6 antibody-negative MPA patients.

Conclusions

Collective findings suggested that anti-MYL6 antibody disrupted actin rearrangement necessary for NET formation and could reduce the disease activity of MPA.

MPA

NETs

ANETA

anti-MYL6 antibody

Microscopic polyangiitis (MPA) is an anti-neutrophil cytoplasmic antibody (ANCA)-associated small-vessel vasculitis [1]. This disease develops necrotizing and crescentic glomerulonephritis and pulmonary hemorrhage due to capillaritis typically with myeloperoxidase (MPO)-ANCA production in the serum [2, 3]. Previous studies have revealed that neutrophils excessively activated by MPO-ANCA are critically involved in MPA pathogenesis [4]. In addition to reactive oxygen species and proteolytic enzymes, neutrophil extracellular traps (NETs) released from activated neutrophils play an important role in tissue destruction in MPA [5].

NETs are extracellular web-like substances that consist of unraveled DNA coating with antimicrobial proteins released from activated neutrophils [6]. Although NETs play roles in capturing and killing microbes invading the hosts and are essential for innate immunity, an excessive NET formation has adverse aspects, such as cytotoxicity [7], thrombogenicity [8], and autoantigenicity [9]. Therefore, NETs are adequately degraded after accomplishing their roles [10].

Recent studies have demonstrated that some patients with MPA possess antibodies to NETs [anti-NET antibody (ANETA)] [11–13]. Currently, ANETA can be detected only by indirect immunofluorescence tests using NETs as substrates, which bind ANETA more strongly than neutrophils used as substrates. Some ANETA can affect NET generation and degradation [11–14]. More recently, myosin light chain 6 (MYL6) has been identified as an antigen of ANETA affecting NET formation [15].

Myosin is a hexameric ATPase cellular motor protein composed of two heavy chains, two nonphosphorylatable alkali light chains, and two phosphorylatable regulatory light chains [16]. MYL6 is one of the nonphosphorylatable alkali light chains. Myosin mediates the morphological alteration and movement of cells by interacting with F-actin. F-actin is a cytoskeletal filamentous protein formed by the polymerization of spherical G-actin as a monomer.

A morphological change in cells results from a rearrangement of the cytoskeleton. G-actin polymerization into F-actin is required for NET formation [17]. In contrast, F-actin degradation is essential for NET formation [18]. Although actin dynamics during NET formation has not been fully revealed, it can be assumed that anti-MYL6 antibody disturbs actin dynamics in which F-actin is involved and consequently affects NET formation.

This study first assessed the influence of anti-MYL6 antibody on NET formation and actin rearrangement in vitro. Next, an enzyme-linked immunosorbent assay (ELISA) was established to detect serum anti-MYL6 antibody, and the prevalence in patients with MPA was determined. Lastly, the association of anti-MYL6 antibody with the disease activity and response to remission-induction therapy of MPA was examined.

NET induction under the presence of anti-MYL6 antibody

After obtaining written informed consent, peripheral blood (10 mL) was drawn from healthy volunteers. Neutrophils extracted from blood using Polymorphprep (Axis-Shield, Dundee, Scotland) were suspended in RPMI 1640 medium containing 10% fetal bovine serum (1×10⁶/mL), seeded in chambers of four-well chamber slides (400 μL/well), and preincubated for 30 min at 37°C. Cells were exposed to 20 nM phorbol 12-myristate 13-acetate (PMA; Sigma-Aldrich, St. Louis, MO, USA) with 0.5 μg/mL anti-human MYL6 polyclonal antibody (rabbit IgG; Abcepta, San Diego, CA, USA) or rabbit IgG (Abcam, Cambridge, UK) as a control for 4 h at 37°C. After rinsing with phosphate-buffered saline (PBS), the samples were mounted with a mounting solution containing 4¢,6-diamidino-2-phenylindole (DAPI; Vector Laboratories, Burlingame, CA, USA).

Fluorescent staining for actin

NETs were induced in peripheral blood neutrophils by PMA with or without anti-MYL6 antibody as above. Before and 30 min, 1 h, and 3 h after incubation, the samples were fixed with 4% paraformaldehyde for 15 min and permeated with 0.5% Triton X-100 for 5 min at room temperature (RT). Thereafter, the samples were reacted with 1:100 dilution of anti-β-actin monoclonal antibody (mAb; mAbcam 8226, mouse IgG1; Abcam) or equivalent concentrations of isotype control mouse IgG1 (Abcam) at 4°C overnight. After rinsing with PBS, the samples were reacted with 4 μg/mL Alexa Fluor 488-conjugated goat anti-mouse IgG1 antibody (Abcam) and 100 nM Acti-stain 555 phalloidin (Cytoskeleton, Denver, CO, USA) for 1 h at RT in the dark. In cells, actin exists in two different forms: nonpolymerized granular form (G-actin) and polymerized filamentous form (F-actin). Anti-β-actin antibody recognizes G-actin [19], whereas phalloidin binds specifically to F-actin. The samples were finally mounted with the mounting solution containing DAPI.

Patients and healthy controls (HCs)

This study enrolled 59 patients with MPA in the RemIT-JAV-RPGN cohort [20-26]. Fifteen patients with granulomatosis with polyangiitis (GPA) and 18 patients with eosinophilic granulomatosis with polyangiitis (EGPA) in the same cohort were included as other ANCA-associated vasculitis (AAV) controls. Nine volunteers were enrolled as HCs.

Serum preparation

After acquiring written informed consent, peripheral blood (10 mL) was taken without anticoagulants, and blood was centrifuged at 1900 g for 15 min at RT for serum separation. Although patients in the RemIT-JAV-RPGN cohort received remission-induction and maintenance therapy based on the discretion of the site clinicians according to the Japanese Ministry of Health, Labour, and Welfare guidelines for AAV treatment [27], blood sampling was carried out before treatment initiation. The serum samples were stored at -20°C before use.

Clinical parameters

Regarding patients with AAV, the Birmingham vasculitis activity score (BVAS) [28] was accessed before treatment. BVAS comprises nine evaluation items, including general, cutaneous, mucous membranes/eyes, ENT (ear, nose, and throat), chest, cardiovascular, abdominal, renal, and nervous system scores. Antigen specificity of ANCA, blood nitrogen urea (BUN), creatinine (Cr), and C-reactive protein (CRP) was determined at the time of blood sampling. Remission 6 months after treatment initiation was defined as BVAS 0 on two occasions at least 1 month apart according to EULAR recommendations [29].

Establishment of ELISAplates for anti-MYL6 antibody detection

Recombinant human MYL6 (0.5 µg/mL; Novus Biologicals, Centennial, CO, USA) was applied to a 96-well plate (50 µL/well) overnight at 4℃ for immobilization. After washing with ELISA wash buffer (Cell Signaling Technology, Danvers, MA, USA), 1% skim milk was applied (150 µL/well) for 1 h at RT to avoid nonspecific binding of antibodies. As a primary antibody, rabbit anti-human MYL6 polyclonal antibody was applied at 0, 0.1, 0.2, 0.4, 0.8, and 1.6 µg/mL (50 µL/well), and the plate was allowed to settle for 1 h at RT. After washing with the buffer, 1:10,000 dilution of horseradish peroxidase (HRP)-conjugated goat anti-rabbit IgG antibody (Jackson ImmunoResearch, West Grove, PA, USA) was applied as a secondary antibody (50 µL/well), and the plate was allowed to settle for 1 h at RT. After washing with the buffer, 3,3',5,5'-tetramethylbenzidine solution (SeraCare Life Sciences, Milford, MA, USA) was applied (50 µL/well), and the plate was allowed to settle for 30 min at RT in the dark. Then, 1 M hydrochloric acid was applied (50 µL/well) to stop the reaction. Optical density (OD) was measured at the main wavelength of 450 nm and subwavelength of 620 nm.

Quantification of anti-MYL6 antibody in sera of patients with AAV

To detect anti-MYL6 antibody in human serum samples, MYL6-immobilized ELISA plates were employed. Human serum samples (1:100 dilution) and HRP-conjugated rabbit anti-human IgG antibody (1:10,000 dilution; GeneTex, Irvine, CA, USA) were used instead of primary and secondary antibodies, respectively. First, using nine sera of HCs, the cutoff OD value of this ELISA was determined as 0.482 [mean+1.5 standard deviation (SD)]. Next, the serum anti-MYL6 antibody titer of 92 patients with AAV, including 59 with MPA, 15 with GPA, and 18 with EGPA, was determined.

Comparison of clinical parameters between anti-MYL6 antibody-positive and -negative MPA patients

Clinical parameters, including BUN, Cr, CRP, and BVAS (total score and each evaluation item score), were compared between anti-MYL6 antibody-positive and -negative MPA patients. The proportion of patients with remission 6 months after initiation of remission-induction therapy was also compared between the two groups.

Statistics

The Student’s t-test or χ²test was applied to compare the clinical parameters between anti-MYL6 antibody-positive and -negative MPA patients. P<0.05 was considered statistically significant.

Effects of anti-MYL6 antibody on NET formation and actin rearrangement induced by PMA

To determine the effects of anti-MYL6 antibody on NET formation, peripheral blood neutrophils from healthy volunteers were stimulated by PMA with or without anti-MYL6 antibody, and NET formation was evaluated by DAPI staining 4 h after incubation. Although extracellular DNA release was observed when neutrophils were stimulated by PMA with the control rabbit IgG, it was evidently suppressed under the presence of anti-MYL6 antibody (Fig. 1a). Because PMA-induced extracellular DNA included the NET marker citrullinated histone H3 [30], NET formation was suppressed by anti-MYL6 antibody.

To follow the actin dynamics during NET formation, chronological double staining for G- and F-actin was performed on PMA-stimulated neutrophils. In Fig. S1, G-actin was detected in neutrophils before and 30 min after PMA stimulation, whereas F-actin was detected in neutrophils 30 min and 1 h after PMA stimulation. At 3 h after PMA stimulation, where NET formation was virtually completed, neither G- nor F-actin was detected in neutrophils. These findings suggested that G-actin polymerization into F-actin could occur in an early period during NET formation, followed by F-actin degradation, consistent with Stojkov et al. [17] and Metzler et al. [18].

Based on this finding, G- and F-actin distribution in neutrophils stimulated by PMA with or without anti-MYL6 antibody was examined 1 h after incubation. Although F-actin with swollen DNA was observed in a part of neutrophils stimulated by PMA with the control rabbit IgG, it was evidently suppressed, and G-actin remained in neutrophils under the presence of anti-MYL6 antibody (Fig. 1b).

These findings suggested that anti-MYL6 antibody could suppress NET formation by disrupting G-actin polymerization into F-actin essential for NET formation.

Prevalence Of Anti-myl6 Antibody In Mpa

A reasonably good calibration curve was obtained using MYL6-immobilized ELISA plates with the commercially available anti-MYL6 antibody (rabbit IgG) as a primary antibody and HRP-conjugated anti-rabbit IgG as a secondary antibody. Using MYL6-immobilized ELISA plates, the serum titer of anti-MYL6 antibody was quantified with the replacement of HRP-conjugated anti-human IgG as the secondary antibody. First, the cutoff OD value of this ELISA was determined as 0.482 (mean + 1.5 SD) using nine HC samples. Next, the serum titer of anti-MYL6 antibody in 59 patients with MPA in the RemIT-JAV-RPGN cohort was measured. As AAV controls other than MPA, the serum titer of anti-MYL6 antibody in 15 patients with GPA and 18 patients with EGPA was also measured. The comparison of clinical characteristics among three subtypes of AAV is summarized in Table 1. The number of anti-MYL6 antibody-positive patients was 7 in MPA (11.9%), whereas 6.7% (1/15) in GPA and 5.6% (1/18) in EGPA were positive for anti-MYL6 antibody (Fig. 2).

Table 1

RemIT-JAV-RPGN cohort patients enrolled in this study
	MPA (n = 59)	GPA (n = 15)	EGPA (n = 18)
Age	69.4 ± 13.0	63.8 ± 20.0	56.8 ± 15.9^a
Sex (F/M)	28/31	10/5	13/5
BUN (mg/dl)	40.7 ± 24.5	31.7 ± 24.8	13.0 ± 3.5^a
Cr (mg/dl)	3.19 ± 2.91	2.54 ± 2.46	0.68 ± 0.18^a
CRP (mg/dl)	6.90 ± 6.89	8.75 ± 6.46	4.85 ± 5.18
BVAS	16.9 ± 4.9^b	17.0 ± 8.0	18.9 ± 6.9
Remission (yes/no)	45/14	13/2	16/2*
^aP<0.01 vs. MPA, *Includes unknown outcome (n = 1).

Association Of Anti-myl6 Antibody And Clinical Parameters Of Mpa

Clinical parameters, including BUN, Cr, CRP, and BVAS, were compared between anti-MYL6 antibody-positive MPA patients (n = 7) and anti-MYL6 antibody-negative MPA patients (n = 52). Among them, the BVAS of anti-MYL6 antibody-positive MPA patients was significantly lower than anti-MYL6 antibody-negative MPA patients (14.4±1.8 vs. 17.2±5.1; p = 0.009; Fig. 3). Concerning the nine evaluation items of BVAS, the cutaneous, cardiovascular, and nervous system scores of anti-MYL6 antibody-positive MPA patients were significantly lower than anti-MYL6 antibody-negative MPA patients (p = 0.0128, p = 0.0148, and p < 0.001, respectively), although other items, including the renal and chest scores, were equivalent between the two groups (Fig. 4). Moreover, the proportion of patients with remission 6 months after initiation of remission-induction therapy in anti-MYL6 antibody-positive MPA patients was significantly higher than in anti-MYL6 antibody-negative MPA patients (p = 0.014; Table 2).

Table 2

Comparison of remission rate 6 months after treatment between anti-MYL6 antibody-positive and -negative MPA patients
MPA (n = 59)		Response to remission-induction therapy		Total
		Remission	No remission
Anti-MYL6	Positive	7*	0	7
	Negative	38	14	52
*P < 0.05.

ANCA induces NETs [31], and NET induction is enhanced in patients with AAV because semaphorin 4D expression on neutrophils, which mediates inhibitory signals for NET formation, is decreased [32]. In addition, reduction of serum activity of DNase I, a physiological degrader of NETs, and acquired resistance to DNase I of NETs contribute to NET accumulation in patients with AAV [11, 30]. In contrast, persistent NETs result in ANCA production [9]. Therefore, a vicious cycle of NETs and ANCA is considered to be involved in AAV pathogenesis [5].

Recent studies have demonstrated that some MPA patients possess ANETA [11–13]. A kind of ANETA induced NETs and was thought to be implicated in the relapse of MPA [12]. Others have a NET degradation inhibitory activity, potentially suspected of promoting NETs and ANCA vicious cycle in MPA [11, 13]. ANETA with NET degradation inhibitory activity has also been reported in antiphospholipid syndrome [14]. In this study, a unique property of ANETA that recognizes MYL6 has been demonstrated.

MYL6 is a component of hexameric ATPase cellular motor protein myosin that interacts with F-actin. The dynamics of myosin and F-actin mediates the morphological alteration of cells, including NET formation. Thus, it was speculated that anti-MYL6 antibody would interfere with the interaction between myosin and F-actin and consequently affect NET formation. When neutrophils were stimulated by PMA with anti-MYL6 antibody, NET formation was obviously suppressed. Meanwhile, G-actin did not polymerize into F-actin and remained in neutrophils.

Based on these findings, NET induction was suppressed by anti-MYL6 antibody via the disruption of actin rearrangement essential for NET formation [17], and myosin might be required for G-actin polymerization. Further studies need to determine why G-actin polymerization into F-actin is disrupted when the interaction between myosin and F-actin is interfered with anti-MYL6 antibody.

The adverse actions of NETs, including cytotoxicity [7], thrombogenicity [8], and autoantigenicity [9], are critically involved in AAV pathogenesis [5]. Therefore, whether anti-MYL6 antibody with NET formation inhibitory potential could reduce the disease activity of MPA was investigated. This study indicated that the BVAS, especially the cutaneous, cardiovascular, and nervous system evaluation items, of anti-MYL6 antibody-positive MPA patients was lower than anti-MYL6 antibody-negative MPA patients and that the proportion of patients with remission 6 months after initiation of remission-induction therapy in anti-MYL6 antibody-positive MPA patients was significantly higher than in anti-MYL6 antibody-negative MPA patients. These findings were consistent with reports of the involvement of NETs in cutaneous and nervous system lesions in AAV [33, 34] and cardiovascular diseases [35]. Collective findings suggested that anti-MYL6 antibody could be a disease-protective autoantibody. Another recent study has demonstrated that anti-serpin B13 autoantibody possesses the potential to prevent type 1 diabetes [36]. Disease-protective autoantibodies will be worthy of attention in upcoming studies.

The limitation of this study includes the small number of disease controls. Although the prevalence of anti-MYL6 antibody positivity seemed to be lower in GPA (6.7%) and EGPA (5.6%) than in MPA (11.9%), there was no statistical power. Further studies need to determine whether the disease activity of GPA and EGPA in patients with anti-MYL6 antibody is lower than in anti-MYL6 antibody-negative GPA/EGPA patients. To the authors’ knowledge, anti-MYL6 antibody has not yet been described in the literature. To determine that this autoantibody is specific to MPA or AAV, its production in patients with vasculitis other than AAV and other autoimmune diseases is required. In addition, whether anti-MYL6 antibody is produced after ANCA production or these autoantibodies are produced independently remains elusive.

Although further studies are needed, this study considers that anti-MYL6 antibody can disrupt actin rearrangement necessary for NET formation and possibly reduce the disease activity of MPA.

AAV

ANCA-associated vasculitis

ANCA

anti-neutrophil cytoplasmic antibody

ANETA

Anti-NET antibody

BUN

Blood nitrogen urea

BVAS

Birmingham vasculitis activity score

Creatinine

CRP

C-reactive protein

DAPI

4′,6-Diamidino-2-phenylindole

EGPA

Eosinophilic granulomatosis with polyangiitis

ELISA

Enzyme-linked immunosorbent assay

GPA

Granulomatosis with polyangiitis

Healthy control

HRP

Horseradish peroxidase

mAb

Monoclonal antibody

MPA

Microscopic polyangiitis

MPO

Myeloperoxidase

MYL6

Myosin light chain 6

NETs

Neutrophil extracellular traps

Optical density

PBS

Phosphate-buffered saline

PMA

Phorbol 12-myristate 13-acetate

room temperature

Standard deviation

Acknowledgments

This study was supported by grants from the Ministry of Health, Labour, and Welfare of Japan for the Japan Research Committee for Intractable Vasculitis (JPVAS; 20FC1044) and the Japan Agency for Medical Research and Development (ek0109360h0003).

Authors’ Contributions

A.I. designed the research. M.Y., Y.N., and S.M. performed the experiments. M.Y., Y.N., S.M., D.N., U.T., and A.I. analyzed the data. Y.A., K.A., Y.Y., KE.S., T.A., H.D., H.H., M.H., Y.T., M.S., S.M., and H.M. collected the serum samples. A.I. wrote the manuscript. All authors discussed the results and contributed to the preparation of the manuscript.

Availability of data and materials

The data used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Ethics approval

The use of human materials in this study was approved by the Ethical Committee of the Faculty of Health Sciences, Hokkaido University (permission nos. 18-34 and 18-68), and the experiments were performed in adherence with the Declaration of Helsinki.

Consent for publication

Not applicable.

Competing interests

T.A. received research grants, speaking fees, and/or consultancy fees from AbbVie Inc., Alexion Inc., Asahi-Kasei Co., Astellas Pharma Inc., AstraZeneca plc., Bayer Yakuhin, Bristol-Myers Squibb Co., Chugai Pharmaceutical Co., Ltd., Daiichi Sankyo Co., Ltd., Eisai Co. Ltd., Eli Lilly Japan K.K., Gilead Sciences K.K., GlaxoSmithKline K.K., Janssen Pharmaceutical K.K., Kyowa Kirin Co., Ltd., Novartis Pharma K.K., Nippon Boehringer Ingelheim Co., Ltd., Mitsubishi Tanabe Pharma Co., Ono Pharmaceutical Co. Ltd., Otsuka Pharmaceutical Co., Ltd. Pfizer Inc., Taiho Pharmaceutical Co., Ltd. Takeda Pharmaceutical Co., Ltd., Teijin Pharma Ltd., and UCB Japan Co. Ltd. KE.S. received a speaker’s fee from Glaxo Smith Kline K.K. and a research grant from Pfizer Inc. H.M. served on steering committees for AbbVie Inc., and Teijin Pharma Ltd. and advisory boards for Nippon Boehringer Ingelheim Co., Ltd. and Travere Therapeutics.

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Competing interest reported. T.A. received research grants, speaking fees, and/or consultancy fees from AbbVie Inc., Alexion Inc., Asahi-Kasei Co., Astellas Pharma Inc., AstraZeneca plc., Bayer Yakuhin, Bristol-Myers Squibb Co., Chugai Pharmaceutical Co., Ltd., Daiichi Sankyo Co., Ltd., Eisai Co. Ltd., Eli Lilly Japan K.K., Gilead Sciences K.K., GlaxoSmithKline K.K., Janssen Pharmaceutical K.K., Kyowa Kirin Co., Ltd., Novartis Pharma K.K., Nippon Boehringer Ingelheim Co., Ltd., Mitsubishi Tanabe Pharma Co., Ono Pharmaceutical Co. Ltd., Otsuka Pharmaceutical Co., Ltd. Pfizer Inc., Taiho Pharmaceutical Co., Ltd. Takeda Pharmaceutical Co., Ltd., Teijin Pharma Ltd., and UCB Japan Co. Ltd. KE.S. received a speaker’s fee from Glaxo Smith Kline K.K. and a research grant from Pfizer Inc. H.M. served on steering committees for AbbVie Inc., and Teijin Pharma Ltd. and advisory boards for Nippon Boehringer Ingelheim Co., Ltd. and Travere Therapeutics.

FigureS1.pdf
Figure S1. Chronological G- and F-actin distribution in neutrophils stimulated by PMA NETs were induced in peripheral blood neutrophils by 20 nM PMA. Before and 30 min, 1 h, and 3 h after incubation, the samples were fixed with 4% paraformaldehyde for 15 min and permeated with 0.5% Triton X-100 for 5 min at RT. Thereafter, the samples were reacted with 1:100 dilution of anti-β-actin mAb (mouse IgG1) at 4°C overnight. After rinsing with PBS, the samples were next reacted with 4 μg/mL Alexa Fluor 488-conjugated goat anti-mouse IgG1 antibody and 100 nM Acti-stain 555 phalloidin for 1 h at RT in the dark. The samples were finally mounted with the mounting solution containing DAPI. Anti-β-actin antibody recognizes G-actin, whereas phalloidin binds specifically to F-actin. Bar, 50 μm.

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Editorial decision: Major revision
28 Oct, 2022
Reviews received at journal
17 Oct, 2022
Reviewers agreed at journal
06 Oct, 2022
Reviewers invited by journal
03 Oct, 2022
Editor assigned by journal
21 Sep, 2022
Submission checks completed at journal
21 Sep, 2022
First submitted to journal
20 Sep, 2022

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Low disease activity of microscopic polyangiitis in patients with anti-myosin light chain 6 antibody that disrupts actin rearrangement necessary for neutrophil extracellular trap formation

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Version 1

Abstract

Background

Methods

Results

Conclusions

Figures

Background

Materials And Methods

Results

Effects of anti-MYL6 antibody on NET formation and actin rearrangement induced by PMA

Prevalence Of Anti-myl6 Antibody In Mpa

Association Of Anti-myl6 Antibody And Clinical Parameters Of Mpa

Discussion

Conclusions

Abbreviations

Declarations

References

Additional Declarations

Supplementary Files

Status:

Version 1