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The association of anti-annexin1 antibodies with the occurrence of skin lesions in systemic lupus erythematosus Z Meng, Z-R Shi, G-Z Tan, J Yin, J Wu, X-B Mi and L Wang Lupus 2014 23: 183 originally published online 3 December 2013 DOI: 10.1177/0961203313513820 The online version of this article can be found at: http://lup.sagepub.com/content/23/2/183
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The association of anti-annexin1 antibodies with the occurrence of skin lesions in systemic lupus erythematosus Z Meng1, Z-R Shi1, G-Z Tan1, J Yin2, J Wu3, X-B Mi4 and L Wang1 1
Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, China; 2Department of Internal Medicine Oncology, Affiliated Hospital of Shandong Academy of Medical Science, China; 3Guangdong Provincial Institute of Geriatrics, Guangdong General Hospital and Guangdong Academy of Medical Science, China; and 4Department of Dermatology, Zhujiang Hospital, Southern Medical University, China
Anti-annexin1 antibodies are associated with the subtypes of cutaneous lupus and are elevated in systemic lupus erythematosus (SLE) patients. In this study, we investigated the correlation of this antibody with the incidence of SLE skin lesions. The presence of anti-annexin1-IgG andIgM determined by Western blot was no different among healthy controls and SLE patients with and without skin lesions. Serum levels of anti-annexin1-IgG and -IgM measured by enzyme-linked immunosorbent assay were comparable between patients with and without skin lesions, whereas anti-annexin1-IgM was lower in SLE patients than in healthy controls. Annexin1 was abundantly detected in each epidermal layer in lupus lesional skin. Additionally, anti-annexin1-IgG was higher in SLE patients with arthritis and negatively correlated with white blood cells (WBC). Anti-annexin1-IgM was higher in patients with antinuclear antibody (ANA)-positive sera, and was positively related to hemoglobin and total serum IgM. Collectively, anti-annexin1 antibodies are not related to the incidence of skin lesions in SLE, and annexin1 abundantly distributes in epidermis in lesional skin. Lupus (2014) 23, 183–187. Key words: Systemic lupus erythematosus; cutaneous lesion; annexin1; anti-annexin1 antibodies
Introduction Annexin1 is an important member of the phospholipid-binding proteins named annexins.1 It is expressed in all kinds of cells, and is especially high in hematopoietic cells including neutrophils, monocytes and macrophages.2 Functionally, annexin1 is an endogenous anti-inflammatory protein and plays a critical role in diverse cellular functions, such as membrane aggregation, phagocytosis, proliferation and apoptosis.3 Recent research has suggested that annexin1 was involved in certain autoimmune disorders such as experimental allergic encephalomyelitis (EAE), multiple sclerosis (MS) and systemic lupus erythematosus (SLE).4–6 Anti-annexin1-immunoglobulin (Ig)G and -IgM antibodies were higher in SLE patients than in healthy controls, with anti-annexin1-IgM even higher in active SLE. The elevation was not related to corticosteroid dosage, antinuclear
antibodies (ANA), anti-double-stranded DNA (anti-dsDNA), anticardiolipin levels, or immune precipitins to extractable nuclear antigens.6 Interestingly, recent research demonstrated that anti-annexin1 antibodies were higher in discoid lupus erythematosus (DLE) than in subacute cutaneous lupus erythematosus (SCLE) and lupus erythematosus tumidus (LET), and suggested that anti-annexin1 antibodies could be a marker of different types of cutaneous lupus.7 In this study, we involved two groups of SLE patients with and without cutaneous lesions that were comparable in SLE Disease Activity Index (SLEDAI) score, to investigate whether antiannexin1-IgG/IgM were related to the occurrence of skin lesions.
Methods Patients
Correspondence to: Liangchun Wang, 107 Yanjiang Rd W, Guangzhou, 510120 China. Email: [email protected] Received 5 August 2013; accepted 29 October 2013
All patients were diagnosed as having SLE according to the American College of Rheumatology’s revised criteria.8 Disease activity was evaluated
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10.1177/0961203313513820
The association of anti-annexin1 antibodies with the occurrence of skin lesions in SLE Z Meng et al.
184
with SLEDAI.9 Eighteen SLE patients without skin lesions, 19 with skin lesions and 20 healthy controls were involved in this study. Serum was collected and stored at 80 C. Five-millimeter biopsy samples from lupus skin lesions were obtained and rapidly frozen at 40 C in isopentane (SigmaAldrich). Normal skin control was the residue of a healthy skin graft from the ear-nose-throat (ENT) department. The study was approved by the research ethics board of Sun Yat-sen Memorial Hospital and informed consent of blood donors was obtained. Western blot to examine anti-annexin1-IgG, -IgM in SLE serum Briefly, recombinant human annexin1 (Abcam, USA) was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), transferred onto polyvinylidene difluoride (PVDF) membranes (Millpore, USA). The membranes were sequentially incubated with patient serum diluted 1:30 and the secondary antibody of horseradish peroxidase (HRP)-conjugated anti-human-IgG or anti-human-IgM antibodies (Sigma-Aldrich, USA). The bound antibodies were visualized by enhanced chemiluminescent (ECL) kit (Boster, China). Enzyme-linked immunosorbent assay (ELISA) to quantify serum anti-annexin1-IgG, -IgM ELISA to detect serum anti-annexin1 antibodies was based on Goulding et al.6 Briefly, 96-well plates were coated with annexin1 at 1 mg/ml, and sequentially incubated with serum samples diluted 1:500–1000 and HRP-conjugated anti-human-IgG or -IgM antibodies (Sigma-Aldrich, USA). The color was developed with 3,3’,5,5’-tetramethylbenzidine dihydrochloride (TMB) and measured in a plate reader at 450 nm (SpectraMax M5, Molecular Devices, USA). Antibody titers were expressed as absorbance units (AU). Immunohistochemical staining of annexin1 protein in cutaneous lupus lesions Frozen samples were cut into 6-mm sections, collected on poly-L-lysine-coated slides, and fixed in acetone. The sections were blocked with 3% H2O2, and sequentially incubated with anti-annexin1 antibodies (Abcam, USA) and HRP-conjugated antimouse antibodies (Zhong shan, China), followed by developing color with 3,30 -diaminobenzidine tetrahydrochloride (DAB) kit (Zhong shan, China). The slides were counterstained with Mayer’s
hematoxylin and mounted using neutral gum. Images were captured with a microscope (Nikon, Japan). Statistical analysis The measurement data were analyzed by MannWhitney test between two groups and by one-way analysis of variance (ANOVA) followed by Dunn’s test among three groups. Pearson Chi-square test was used for all enumeration data. The correlation analyses were performed by Spearman’s rank correlation test. Values of p < 0.05 were considered statistically significant.
Results Patients SLE patients were divided into two groups according to the presence and the absence of skin lesions. The age, the gender constitution and the duration of disease were comparable between the two groups. There were no differences between the two groups in respect to proportion of patients with arthritis, renal and neurological disorders, nor in the blood cell counts and the immunologic parameters including antinuclear antibodies (ANA), anti-Sm, anti-dsDNA, serum C3, C4, Igs and erythrocyte sedimentation rate (ESR). SLEDAI was 14.7 1.8 and 17.3 1.6 in patients without and with skin lesions (p ¼ 0.29), respectively. The measurement of serum anti-annexin1-IgG and -IgM and the expression of annexin1 in SLE skin lesions To determine whether serum anti-annexin1 antibodies were related to skin injuries in SLE patients, we examined the positivity and the serum levels of antiannexin1-IgG and -IgM in healthy controls and SLE patients using Western blot and ELISA, respectively. No serum anti-annexin1-IgG was detected by Western blot from any healthy controls and SLE patients regardless of skin lesion (Figure 1(a), upper panel). Conversely, anti-annexin1-IgM was detected from all three groups (Figure 1(a), lower panel), whereas the detected rates identified no differences (Figure 1(b)). The average AU of anti-annexin1-IgG determined by ELISA was 1.84 0.18, 1.58 0.21 and 1.71 0.19 in healthy controls, patients with and without skin lesions, respectively, comparable among the three groups (Figure 1(c,d)). Anti-annnexin1-IgM was
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The association of anti-annexin1 antibodies with the occurrence of skin lesions in SLE Z Meng et al.
185
Figure 1 Serum anti-annexin1-IgG and -IgM antibodies detected by Western blot and ELISA assay. Recombinant human annexin1 was used as detective antigen. The existence of serum anti-annexin-IgG and -IgM antibodies was first detected by Western blot, and the monoclonal antibody (mAb) serves as positive control. (a) Representative data (upper panel, IgG; low panel, IgM). (b) Comparison of the detective rates of anti-annexin1-IgM in healthy controls and SLE patients without and with skin lesions. Serum level of anti-annexin1-IgG (c,d) and -IgM (e,f) were detected by ELISA. The black bar in each column indicates mean. Data are representative of three independent experiments. b: Fisher’s exact test; c,e: Mann-Whitney test; d, f: oneway ANOVA followed by Dunn’s Multiple Comparison Test. *p 12, whereas other studies included patients with inactive disease. The proportion of patients with arthritis and WBC disorders may also contribute to the discrepancy because both factors were demonstrated to be related to the anti-annexin1-IgG level in this study. In agreement with previous research,11 our study showed anti-annexin1 antibody titers were not associated with age, disease duration and SLEDAI. Back to the objective of this study, our data indicate that the prevalence and serum titers of anti-annexin1-IgG and -IgM have no association with the incidence of skin lesions in SLE patients. Annexin1 expression in normal skin varied among studies and was likely related to biopsy sites and patient age.12 Thus, to fairly compare annexin1 expression in skin, we took biopsies from the equal sites of age-matched lupus patients and healthy controls. We indicated that annexin1 was mainly distributed in basal, superbasal and superficial epidermis in healthy skin, whereas it was observed in each layer in the epidermis in lupus lesional skin. To our knowledge, this is the first study of annexin1 expression in lupus lesional skin. Previous research observed that the distribution of annexin1 varied with the disease phase of EAE in the central nervous system and was different from healthy animals.13 This also could be true for interpreting annexin1 distribution in lupus lesional skin. Taken together, our study demonstrates that anti-annexin1-IgG and -IgM antibodies are not related to the occurrence of skin lesions, and that annexin1 abundantly distributes in each epidermal layer, different from its expression in healthy skin.
Funding This study was supported by the National Natural Science Foundation of China (81101196, 81201233), the Natural Science Foundation of
Guangdong Province, China (S2011010003664) and the Fundamental Research Funds for the Central Universities. L.W. is the recipient of the Hundred Outstanding New Investigators of Sun Yat-sen University, and the New Century Outstanding Investigator Award, the Chinese Ministry of Education.
Conflict of interest The authors have no conflicts of interest to declare.
Acknowledgment The authors would like to thank Boyou Li for preparing all of the skin sections.
References 1 Flower RJ, Rothwell NJ. Lipocortin-1: Cellular mechanisms and clinical relevance. Trends Pharmacol Sci 1994; 15: 71–76. 2 D’Acquisto F, Perretti M, Flower RJ. Annexin-A1: A pivotal regulator of the innate and adaptive immune systems. Br J Pharmacol 2008; 155: 152–169. 3 Lim LH, Pervaiz S. Annexin 1: The new face of an old molecule. Faseb J 2007; 21: 968–975. 4 Huitinga I, Bauer J, Strijbos PJ, Rothwell NJ, Dijkstra CD, Tilders FJ. Effect of annexin-1 on experimental autoimmune encephalomyelitis (EAE) in the rat. Clin Exp Immunol 1998; 111: 198–204. 5 Probst-Cousin S, Kowolik D, Kuchelmeister K, Kayser C, Neundorfer B, Heuss D. Expression of annexin-1 in multiple sclerosis plaques. Neuropathol Appl Neurobiol 2002; 28: 292–300. 6 Goulding NJ, Podgorski MR, Hall ND, et al. Autoantibodies to recombinant lipocortin-1 in rheumatoid arthritis and systemic lupus erythematosus. Ann Rheum Dis 1989; 48: 843–850. 7 Kretz CC, Norpo M, Abeler-Dorner L, et al. Anti-annexin 1 antibodies: A new diagnostic marker in the serum of patients with discoid lupus erythematosus. Exp Dermatol 2010; 19: 919–921. 8 Tan EM, Cohen AS, Fries JF, et al. The 1982 revised criteria for the classification of systemic lupus erythematosus. Arthritis Rheum 1982; 25: 1271–1277. 9 Duffy KN, Duffy CM, Gladman DD. Infection and disease activity in systemic lupus erythematosus: A review of hospitalized patients. J Rheumatol 1991; 18: 1180–1184. 10 Arur S, Uche UE, Rezaul K, et al. Annexin I is an endogenous ligand that mediates apoptotic cell engulfment. Dev Cell 2003; 4: 587–598. 11 Pruzanski W, Goulding NJ, Flower RJ, et al. Circulating group II phospholipase A2 activity and antilipocortin antibodies in systemic lupus erythematosus. Correlative study with disease activity. J Rheumatol 1994; 21: 252–257. 12 Fava RA, Nanney LB, Wilson D, King LE Jr. Annexin-1 localization in human skin: Possible association with cytoskeletal elements in keratinocytes of the stratum spinosum. J Invest Dermatol 1993; 101: 732–737. 13 Elderfield AJ, Bolton C, Flower RJ. Lipocortin 1 (annexin 1) immunoreactivity in the cervical spinal cord of Lewis rats with acute experimental allergic encephalomyelitis. J Neurol Sci 1993; 119: 146–153.
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The association of anti-annexin1 antibodies with the occurrence of skin lesions in systemic lupus erythematosus Z Meng, Z-R Shi, G-Z Tan, J Yin, J Wu, X-B Mi and L Wang Lupus 2014 23: 183 originally published online 3 December 2013 DOI: 10.1177/0961203313513820 The online version of this article can be found at: http://lup.sagepub.com/content/23/2/183
Published by: http://www.sagepublications.com
Additional services and information for Lupus can be found at: Email Alerts: http://lup.sagepub.com/cgi/alerts Subscriptions: http://lup.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav
>> Version of Record - Jan 13, 2014 OnlineFirst Version of Record - Dec 3, 2013 What is This?
Downloaded from lup.sagepub.com at UNIV OF PITTSBURGH on November 3, 2014
Lupus (2014) 23, 183–187 http://lup.sagepub.com
CONCISE REPORT
The association of anti-annexin1 antibodies with the occurrence of skin lesions in systemic lupus erythematosus Z Meng1, Z-R Shi1, G-Z Tan1, J Yin2, J Wu3, X-B Mi4 and L Wang1 1
Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, China; 2Department of Internal Medicine Oncology, Affiliated Hospital of Shandong Academy of Medical Science, China; 3Guangdong Provincial Institute of Geriatrics, Guangdong General Hospital and Guangdong Academy of Medical Science, China; and 4Department of Dermatology, Zhujiang Hospital, Southern Medical University, China
Anti-annexin1 antibodies are associated with the subtypes of cutaneous lupus and are elevated in systemic lupus erythematosus (SLE) patients. In this study, we investigated the correlation of this antibody with the incidence of SLE skin lesions. The presence of anti-annexin1-IgG andIgM determined by Western blot was no different among healthy controls and SLE patients with and without skin lesions. Serum levels of anti-annexin1-IgG and -IgM measured by enzyme-linked immunosorbent assay were comparable between patients with and without skin lesions, whereas anti-annexin1-IgM was lower in SLE patients than in healthy controls. Annexin1 was abundantly detected in each epidermal layer in lupus lesional skin. Additionally, anti-annexin1-IgG was higher in SLE patients with arthritis and negatively correlated with white blood cells (WBC). Anti-annexin1-IgM was higher in patients with antinuclear antibody (ANA)-positive sera, and was positively related to hemoglobin and total serum IgM. Collectively, anti-annexin1 antibodies are not related to the incidence of skin lesions in SLE, and annexin1 abundantly distributes in epidermis in lesional skin. Lupus (2014) 23, 183–187. Key words: Systemic lupus erythematosus; cutaneous lesion; annexin1; anti-annexin1 antibodies
Introduction Annexin1 is an important member of the phospholipid-binding proteins named annexins.1 It is expressed in all kinds of cells, and is especially high in hematopoietic cells including neutrophils, monocytes and macrophages.2 Functionally, annexin1 is an endogenous anti-inflammatory protein and plays a critical role in diverse cellular functions, such as membrane aggregation, phagocytosis, proliferation and apoptosis.3 Recent research has suggested that annexin1 was involved in certain autoimmune disorders such as experimental allergic encephalomyelitis (EAE), multiple sclerosis (MS) and systemic lupus erythematosus (SLE).4–6 Anti-annexin1-immunoglobulin (Ig)G and -IgM antibodies were higher in SLE patients than in healthy controls, with anti-annexin1-IgM even higher in active SLE. The elevation was not related to corticosteroid dosage, antinuclear
antibodies (ANA), anti-double-stranded DNA (anti-dsDNA), anticardiolipin levels, or immune precipitins to extractable nuclear antigens.6 Interestingly, recent research demonstrated that anti-annexin1 antibodies were higher in discoid lupus erythematosus (DLE) than in subacute cutaneous lupus erythematosus (SCLE) and lupus erythematosus tumidus (LET), and suggested that anti-annexin1 antibodies could be a marker of different types of cutaneous lupus.7 In this study, we involved two groups of SLE patients with and without cutaneous lesions that were comparable in SLE Disease Activity Index (SLEDAI) score, to investigate whether antiannexin1-IgG/IgM were related to the occurrence of skin lesions.
Methods Patients
Correspondence to: Liangchun Wang, 107 Yanjiang Rd W, Guangzhou, 510120 China. Email: [email protected] Received 5 August 2013; accepted 29 October 2013
All patients were diagnosed as having SLE according to the American College of Rheumatology’s revised criteria.8 Disease activity was evaluated
! The Author(s), 2013. Reprints and permissions: http://www.sagepub.co.uk/journalsPermissions.nav
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10.1177/0961203313513820
The association of anti-annexin1 antibodies with the occurrence of skin lesions in SLE Z Meng et al.
184
with SLEDAI.9 Eighteen SLE patients without skin lesions, 19 with skin lesions and 20 healthy controls were involved in this study. Serum was collected and stored at 80 C. Five-millimeter biopsy samples from lupus skin lesions were obtained and rapidly frozen at 40 C in isopentane (SigmaAldrich). Normal skin control was the residue of a healthy skin graft from the ear-nose-throat (ENT) department. The study was approved by the research ethics board of Sun Yat-sen Memorial Hospital and informed consent of blood donors was obtained. Western blot to examine anti-annexin1-IgG, -IgM in SLE serum Briefly, recombinant human annexin1 (Abcam, USA) was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), transferred onto polyvinylidene difluoride (PVDF) membranes (Millpore, USA). The membranes were sequentially incubated with patient serum diluted 1:30 and the secondary antibody of horseradish peroxidase (HRP)-conjugated anti-human-IgG or anti-human-IgM antibodies (Sigma-Aldrich, USA). The bound antibodies were visualized by enhanced chemiluminescent (ECL) kit (Boster, China). Enzyme-linked immunosorbent assay (ELISA) to quantify serum anti-annexin1-IgG, -IgM ELISA to detect serum anti-annexin1 antibodies was based on Goulding et al.6 Briefly, 96-well plates were coated with annexin1 at 1 mg/ml, and sequentially incubated with serum samples diluted 1:500–1000 and HRP-conjugated anti-human-IgG or -IgM antibodies (Sigma-Aldrich, USA). The color was developed with 3,3’,5,5’-tetramethylbenzidine dihydrochloride (TMB) and measured in a plate reader at 450 nm (SpectraMax M5, Molecular Devices, USA). Antibody titers were expressed as absorbance units (AU). Immunohistochemical staining of annexin1 protein in cutaneous lupus lesions Frozen samples were cut into 6-mm sections, collected on poly-L-lysine-coated slides, and fixed in acetone. The sections were blocked with 3% H2O2, and sequentially incubated with anti-annexin1 antibodies (Abcam, USA) and HRP-conjugated antimouse antibodies (Zhong shan, China), followed by developing color with 3,30 -diaminobenzidine tetrahydrochloride (DAB) kit (Zhong shan, China). The slides were counterstained with Mayer’s
hematoxylin and mounted using neutral gum. Images were captured with a microscope (Nikon, Japan). Statistical analysis The measurement data were analyzed by MannWhitney test between two groups and by one-way analysis of variance (ANOVA) followed by Dunn’s test among three groups. Pearson Chi-square test was used for all enumeration data. The correlation analyses were performed by Spearman’s rank correlation test. Values of p < 0.05 were considered statistically significant.
Results Patients SLE patients were divided into two groups according to the presence and the absence of skin lesions. The age, the gender constitution and the duration of disease were comparable between the two groups. There were no differences between the two groups in respect to proportion of patients with arthritis, renal and neurological disorders, nor in the blood cell counts and the immunologic parameters including antinuclear antibodies (ANA), anti-Sm, anti-dsDNA, serum C3, C4, Igs and erythrocyte sedimentation rate (ESR). SLEDAI was 14.7 1.8 and 17.3 1.6 in patients without and with skin lesions (p ¼ 0.29), respectively. The measurement of serum anti-annexin1-IgG and -IgM and the expression of annexin1 in SLE skin lesions To determine whether serum anti-annexin1 antibodies were related to skin injuries in SLE patients, we examined the positivity and the serum levels of antiannexin1-IgG and -IgM in healthy controls and SLE patients using Western blot and ELISA, respectively. No serum anti-annexin1-IgG was detected by Western blot from any healthy controls and SLE patients regardless of skin lesion (Figure 1(a), upper panel). Conversely, anti-annexin1-IgM was detected from all three groups (Figure 1(a), lower panel), whereas the detected rates identified no differences (Figure 1(b)). The average AU of anti-annexin1-IgG determined by ELISA was 1.84 0.18, 1.58 0.21 and 1.71 0.19 in healthy controls, patients with and without skin lesions, respectively, comparable among the three groups (Figure 1(c,d)). Anti-annnexin1-IgM was
Lupus Downloaded from lup.sagepub.com at UNIV OF PITTSBURGH on November 3, 2014
The association of anti-annexin1 antibodies with the occurrence of skin lesions in SLE Z Meng et al.
185
Figure 1 Serum anti-annexin1-IgG and -IgM antibodies detected by Western blot and ELISA assay. Recombinant human annexin1 was used as detective antigen. The existence of serum anti-annexin-IgG and -IgM antibodies was first detected by Western blot, and the monoclonal antibody (mAb) serves as positive control. (a) Representative data (upper panel, IgG; low panel, IgM). (b) Comparison of the detective rates of anti-annexin1-IgM in healthy controls and SLE patients without and with skin lesions. Serum level of anti-annexin1-IgG (c,d) and -IgM (e,f) were detected by ELISA. The black bar in each column indicates mean. Data are representative of three independent experiments. b: Fisher’s exact test; c,e: Mann-Whitney test; d, f: oneway ANOVA followed by Dunn’s Multiple Comparison Test. *p 12, whereas other studies included patients with inactive disease. The proportion of patients with arthritis and WBC disorders may also contribute to the discrepancy because both factors were demonstrated to be related to the anti-annexin1-IgG level in this study. In agreement with previous research,11 our study showed anti-annexin1 antibody titers were not associated with age, disease duration and SLEDAI. Back to the objective of this study, our data indicate that the prevalence and serum titers of anti-annexin1-IgG and -IgM have no association with the incidence of skin lesions in SLE patients. Annexin1 expression in normal skin varied among studies and was likely related to biopsy sites and patient age.12 Thus, to fairly compare annexin1 expression in skin, we took biopsies from the equal sites of age-matched lupus patients and healthy controls. We indicated that annexin1 was mainly distributed in basal, superbasal and superficial epidermis in healthy skin, whereas it was observed in each layer in the epidermis in lupus lesional skin. To our knowledge, this is the first study of annexin1 expression in lupus lesional skin. Previous research observed that the distribution of annexin1 varied with the disease phase of EAE in the central nervous system and was different from healthy animals.13 This also could be true for interpreting annexin1 distribution in lupus lesional skin. Taken together, our study demonstrates that anti-annexin1-IgG and -IgM antibodies are not related to the occurrence of skin lesions, and that annexin1 abundantly distributes in each epidermal layer, different from its expression in healthy skin.
Funding This study was supported by the National Natural Science Foundation of China (81101196, 81201233), the Natural Science Foundation of
Guangdong Province, China (S2011010003664) and the Fundamental Research Funds for the Central Universities. L.W. is the recipient of the Hundred Outstanding New Investigators of Sun Yat-sen University, and the New Century Outstanding Investigator Award, the Chinese Ministry of Education.
Conflict of interest The authors have no conflicts of interest to declare.
Acknowledgment The authors would like to thank Boyou Li for preparing all of the skin sections.
References 1 Flower RJ, Rothwell NJ. Lipocortin-1: Cellular mechanisms and clinical relevance. Trends Pharmacol Sci 1994; 15: 71–76. 2 D’Acquisto F, Perretti M, Flower RJ. Annexin-A1: A pivotal regulator of the innate and adaptive immune systems. Br J Pharmacol 2008; 155: 152–169. 3 Lim LH, Pervaiz S. Annexin 1: The new face of an old molecule. Faseb J 2007; 21: 968–975. 4 Huitinga I, Bauer J, Strijbos PJ, Rothwell NJ, Dijkstra CD, Tilders FJ. Effect of annexin-1 on experimental autoimmune encephalomyelitis (EAE) in the rat. Clin Exp Immunol 1998; 111: 198–204. 5 Probst-Cousin S, Kowolik D, Kuchelmeister K, Kayser C, Neundorfer B, Heuss D. Expression of annexin-1 in multiple sclerosis plaques. Neuropathol Appl Neurobiol 2002; 28: 292–300. 6 Goulding NJ, Podgorski MR, Hall ND, et al. Autoantibodies to recombinant lipocortin-1 in rheumatoid arthritis and systemic lupus erythematosus. Ann Rheum Dis 1989; 48: 843–850. 7 Kretz CC, Norpo M, Abeler-Dorner L, et al. Anti-annexin 1 antibodies: A new diagnostic marker in the serum of patients with discoid lupus erythematosus. Exp Dermatol 2010; 19: 919–921. 8 Tan EM, Cohen AS, Fries JF, et al. The 1982 revised criteria for the classification of systemic lupus erythematosus. Arthritis Rheum 1982; 25: 1271–1277. 9 Duffy KN, Duffy CM, Gladman DD. Infection and disease activity in systemic lupus erythematosus: A review of hospitalized patients. J Rheumatol 1991; 18: 1180–1184. 10 Arur S, Uche UE, Rezaul K, et al. Annexin I is an endogenous ligand that mediates apoptotic cell engulfment. Dev Cell 2003; 4: 587–598. 11 Pruzanski W, Goulding NJ, Flower RJ, et al. Circulating group II phospholipase A2 activity and antilipocortin antibodies in systemic lupus erythematosus. Correlative study with disease activity. J Rheumatol 1994; 21: 252–257. 12 Fava RA, Nanney LB, Wilson D, King LE Jr. Annexin-1 localization in human skin: Possible association with cytoskeletal elements in keratinocytes of the stratum spinosum. J Invest Dermatol 1993; 101: 732–737. 13 Elderfield AJ, Bolton C, Flower RJ. Lipocortin 1 (annexin 1) immunoreactivity in the cervical spinal cord of Lewis rats with acute experimental allergic encephalomyelitis. J Neurol Sci 1993; 119: 146–153.
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