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2. Hachulla E, Launay D. Diagnosis and classification of systemic sclerosis. *Clin Rev Allergy Immunol* (2011) 40:78-83. doi: 10.1007/s12016-010-8198-y

3. Morell-Dubois S, Condette-Wojtasik G, Clerson P, Berezné A, Launay D, Lambert M, et al. [Complaints, needs of patients with systemic sclerosis: a better understanding for a better care]. *Rev Médecine Interne* (2011) 32:537-43. doi: 10.1016/j.revmed.2011.02.004

4. Lefèvre G, Dauchet L, Hachulla E, Montani D, Sobanski V, Lambert M, et al. Survival and prognostic factors in systemic sclerosis-associated pulmonary hypertension: A systematic review and meta-analysis: Survival and prognosis in SSc-associated pulmonary hypertension. *Arthritis Rheum* (2013) 65:2412-23. doi: 10.1002/art.38029

5. Launay D, Humbert M, Berezne A, Cottin V, Allanore Y, Couderc L-J, et al. Clinical characteristics and survival in systemic sclerosis-related pulmonary hypertension associated with interstitial lung disease. *Chest* (2011) 140:1016-24. doi: 10.1378/chest.10-2473

6. Dumoitier N, Lofek S, Mouthon L. Pathophysiology of systemic sclerosis: State of the art in 2014. *Presse Médicale* (2014) 43:e267-78. doi: 10.1016/j.lpm.2014.08.001

7. Sanges S, Guerrier T, Launay D, Lefèvre G, Labalette M, Forestier A, et al. Role of b cells in the pathogenesis of systemic sclerosis. *Rev Médecine Interne* (2017) 38:113-24. doi: 10.1016/j.revmed.2016.02.016

8. Kill A, Riemekasten G. Functional autoantibodies in systemic sclerosis pathogenesis. *Curr Rheumatol Rep* (2015) 17 34. doi: 10.1007/s11926-015-0505-4

9. Sanges S, Jendoubi M, Kavian N, Hauspie C, Speca S, Crave J-C, et al. B cell homeostasis and functional properties are altered in an hypochlorous acid-induced murine model of systemic sclerosis. *Front Immunol* (2017) 8:53. doi: 10.3389/fimmu.2017.00053

10. Forestier A, Guerrier T, Jouvray M, Giovannelli J, Lefèvre G, Sobanski V, et al. Altered b lymphocyte homeostasis and functions in systemic sclerosis. *Autoimmun Rev* (2018) 17:244-55. doi: 10.1016/j.autrev.2017.10.015

11. Du AX, Gniadecki R, Osman M. Biomarkers of b cell activation in autoimmune connective tissue diseases: More than markers of disease activity. *Clin Biochem* (2022) 100:1-12. doi: 10.1016/j.clinbiochem.2021.11.009

12. Salazar-Camarena DC, Ortiz-Lazareno PC, Cruz A, Oregon-Romero E, Machado-Contreras JR, Muñoz-Valle JF, et al. Association of BAFF, APRIL serum levels, BAFF-r, TACI and BCMA expression on peripheral b-cell subsets with clinical manifestations in systemic lupus erythematosus. *Lupus* (2016) 25:582-92. doi: 10.1177/0961203315608254

13. Laurent SA, Hoffmann FS, Kuhn P-H, Cheng Q, Chu Y, Schmidt-Supprian M, et al. γ-secretase directly sheds the survival receptor BCMA from plasma cells. *Nat Commun* (2015) 6:7333. doi: 10.1038/ncomms8333

14. Hoffmann FS, Kuhn P-H, Laurent SA, Hauck SM, Berer K, Wendlinger SA, et al. The immunoregulator soluble TACI is released by ADAM10 and reflects b cell activation in autoimmunity. *J Immunol* (2015) 194:542-52. doi: 10.4049/jimmunol.1402070

15. Hegazy M, Darwish H, Darweesh H, El-Shehaby A, Emad Y. Raised serum level of APRIL in patients with systemic lupus erythematosus: correlations with disease activity indices. *Clin Immunol Orlando Fla* (2010) 135:118-24. doi: 10.1016/j.clim.2009.12.012

16. Morel J, Roubille C, Panelles L, Rocha C, Fernandez L, Lukas C, et al. Serum levels of tumour necrosis factor family members a proliferation-inducing ligand (APRIL) and b lymphocyte stimulator (BLyS) are inversely correlated in systemic lupus erythematosus. *Ann Rheum Dis* (2009) 68:997-1002. doi: 10.1136/ard.2008.090928

17. Koyama T, Tsukamoto H, Miyagi Y, Himeji D, Otsuka J, Miyagawa H, et al. Raised serum APRIL levels in patients with systemic lupus erythematosus. *Ann Rheum Dis* (2005) 64:1065-7. doi: 10.1136/ard.2004.022491

18. Treamtrakpanon W, Tantivitayakul P, Benjachat T, Somparn P, Kittikowit W, Eiam-ong S, et al. APRIL, a proliferation-inducing ligand, as a potential marker of lupus nephritis. *Arthritis Res Ther* (2012) 14:R252. doi: 10.1186/ar4095

19. Breen EC, Hussain SK, Magpantay L, Jacobson LP, Detels R, Rabkin CS, et al. B-cell stimulatory cytokines and markers of immune activation are elevated several years prior to the diagnosis of systemic AIDS-associated non-Hodgkin b-cell lymphoma. *Cancer Epidemiol Biomarkers Prev* (2011) 20:1303-14. doi: 10.1158/1055-9965.EPI-11-0037

20. De Roos AJ, Mirick DK, Edlefsen KL, LaCroix AZ, Kopecky KJ, Madeleine MM, et al. Markers of b-cell activation in relation to risk of non-Hodgkin lymphoma. *Cancer Res* (2012) 72:4733-43. doi: 10.1158/0008-5472.CAN-12-1639

21. Monach PA, Warner RL, Tomasson G, Specks U, Stone JH, Ding L, et al. Serum proteins reflecting inflammation, injury and repair as biomarkers of disease activity in ANCA-associated vasculitis. *Ann Rheum Dis* (2013) 72:1342-50. doi: 10.1136/annrheumdis-2012-201981

22. Land J, Abdulahad WH, Sanders J-SF, Stegeman CA, Heeringa P, Rutgers A. Regulatory and effector b cell cytokine production in patients with relapsing granulomatosis with polyangiitis. *Arthritis Res Ther* (2016) 18:84. doi: 10.1186/s13075-016-0978-1

23. Nocturne G, Seror R, Fogel O, Belkhir R, Boudaoud S, Saraux A, et al. CXCL13 and CCL11 serum levels and lymphoma and disease activity in primary sjögren's syndrome. *Arthritis Rheumatol Hoboken NJ* (2015) 67:3226-33. doi: 10.1002/art.39315

24. Jones JD, Hamilton BJ, Challener GJ, de Brum-Fernandes AJ, Cossette P, Liang P, et al. Serum c-X-C motif chemokine 13 is elevated in early and established rheumatoid arthritis and correlates with rheumatoid factor levels. *Arthritis Res Ther* (2014) 16:R103. doi: 10.1186/ar4552

25. Hafez SS, Saad WES, Shedid NH. B-cell-attracting chemokine-1 (BCA-1/CXCL13) in systemic lupus erythematosus, its correlation to disease activity and renal involvement. *Egypt J Immunol* (2014) 21:23-32.

26. Greisen SR, Schelde KK, Rasmussen TK, Kragstrup TW, Stengaard-Pedersen K, Hetland ML, et al. CXCL13 predicts disease activity in early rheumatoid arthritis and could be an indicator of the therapeutic "window of opportunity." *Arthritis Res Ther* (2014) 16:434. doi: 10.1186/s13075-014-0434-z

27. Lanteri A, Sobanski V, Langlois C, Lefèvre G, Hauspie C, Sanges S, et al. Serum free light chains of immunoglobulins as biomarkers for systemic sclerosis characteristics, activity and severity. *Autoimmun Rev* (2014) 13:974-80. doi: 10.1016/j.autrev.2014.07.003

28. Bassyouni IH, Azab NA, El-Dakrony E-HM, Fawzi MMT, Ghanoum R, Bassyouni RH. Elevated serum levels of a proliferation-inducing ligand in patients with systemic sclerosis: Possible association with myositis? *Joint Bone Spine* (2011) 78:56-61. doi: 10.1016/j.jbspin.2010.05.004

29. Matsushita T, Fujimoto M, Hasegawa M, Tanaka C, Kumada S, Ogawa F, et al. Elevated serum APRIL levels in patients with systemic sclerosis: distinct profiles of systemic sclerosis categorized by APRIL and BAFF. *J Rheumatol* (2007) 34:2056-62.

30. Pagano L, Paletti S, Afa G, Marra R, Garcovich A, Bizzi B. Serum beta 2-microglobulin in systemic sclerosis. *Clin Rheumatol* (1985) 4:286-9. doi: 10.1007/BF02031609

31. Minh VN, Hau KT, Takashi M, Ha VN, Bao LH, Huyen ML, et al. Efficacy of BAFF in monitoring treatment response in early Vietnamese systemic sclerosis patients. *Open Access Maced J Med Sci* (2019) 7:264-8. doi: 10.3889/oamjms.2019.070

32. Bosello S, Basile U, De Lorenzis E, Gulli F, Canestrari G, Napodano C, et al. Free light chains of immunoglobulins in patients with systemic sclerosis: correlations with lung involvement and inflammatory milieu. *J Clin Pathol* (2018) 71:620-5. doi: 10.1136/jclinpath-2017-204656

33. Wutte N, Kovacs G, Berghold A, Reiter H, Aberer W, Aberer E. CXCL13 and b-cell activating factor as putative biomarkers in systemic sclerosis. *Br J Dermatol* (2013) 169:723-5. doi: 10.1111/bjd.12411

34. Abdo MS, Mohammed RHA, Raslan HM, Gaber SM. Serum b-cell activating factor assessment in a population of Egyptian patients with systemic sclerosis. *Int J Rheum Dis* (2013) 16:148-56. doi: 10.1111/1756-185x.12019

35. Fawzy SM, Gheita TA, El-Nabarawy E, El-Demellawy HH, Shaker OG. Serum BAFF level and its correlations with various disease parameters in patients with systemic sclerosis and systemic lupus erythematosus. *Egypt Rheumatol* (2011) 33:45-51. doi: 10.1016/j.ejr.2010.12.001

36. Matsushita T, Hasegawa M, Yanaba K, Kodera M, Takehara K, Sato S. Elevated serum BAFF levels in patients with systemic sclerosis: Enhanced BAFF signaling in systemic sclerosis b lymphocytes. *Arthritis Rheum* (2006) 54:192-201. doi: 10.1002/art.21526

37. Taniguchi T, Miyagawa T, Toyama S, Yamashita T, Nakamura K, Saigusa R, et al. CXCL13 produced by macrophages due to Fli1 deficiency may contribute to the development of tissue fibrosis, vasculopathy and immune activation in systemic sclerosis. *Exp Dermatol* (2018) 27:1030-7. doi: 10.1111/exd.13724

38. Zhang H, Li P, Wu D, Xu D, Hou Y, Wang Q, et al. Serum IgG subclasses in autoimmune diseases. *Med (Baltimore)* (2015) 94:e387. doi: 10.1097/MD.0000000000000387
References

1. Pokeerbux MR, Giovannelli J, Dauchet L, Mouthon L, Agard C, Lega JC, et al. Survival and prognosis factors in systemic sclerosis: data of a French multicenter cohort, systematic review, and meta-analysis of the literature. *Arthritis Res Ther* (2019) 21:86. doi: 10.1186/s13075-019-1867-1

2. Hachulla E, Launay D. Diagnosis and classification of systemic sclerosis. *Clin Rev Allergy Immunol* (2011) 40:78-83. doi: 10.1007/s12016-010-8198-y

3. Morell-Dubois S, Condette-Wojtasik G, Clerson P, Berezné A, Launay D, Lambert M, et al. [Complaints, needs of patients with systemic sclerosis: a better understanding for a better care]. *Rev Médecine Interne* (2011) 32:537-43. doi: 10.1016/j.revmed.2011.02.004

4. Lefèvre G, Dauchet L, Hachulla E, Montani D, Sobanski V, Lambert M, et al. Survival and prognostic factors in systemic sclerosis-associated pulmonary hypertension: A systematic review and meta-analysis: Survival and prognosis in SSc-associated pulmonary hypertension. *Arthritis Rheum* (2013) 65:2412-23. doi: 10.1002/art.38029

5. Launay D, Humbert M, Berezne A, Cottin V, Allanore Y, Couderc L-J, et al. Clinical characteristics and survival in systemic sclerosis-related pulmonary hypertension associated with interstitial lung disease. *Chest* (2011) 140:1016-24. doi: 10.1378/chest.10-2473

6. Dumoitier N, Lofek S, Mouthon L. Pathophysiology of systemic sclerosis: State of the art in 2014. *Presse Médicale* (2014) 43:e267-78. doi: 10.1016/j.lpm.2014.08.001

7. Sanges S, Guerrier T, Launay D, Lefèvre G, Labalette M, Forestier A, et al. Role of b cells in the pathogenesis of systemic sclerosis. *Rev Médecine Interne* (2017) 38:113-24. doi: 10.1016/j.revmed.2016.02.016

8. Kill A, Riemekasten G. Functional autoantibodies in systemic sclerosis pathogenesis. *Curr Rheumatol Rep* (2015) 17 34. doi: 10.1007/s11926-015-0505-4

9. Sanges S, Jendoubi M, Kavian N, Hauspie C, Speca S, Crave J-C, et al. B cell homeostasis and functional properties are altered in an hypochlorous acid-induced murine model of systemic sclerosis. *Front Immunol* (2017) 8:53. doi: 10.3389/fimmu.2017.00053

10. Forestier A, Guerrier T, Jouvray M, Giovannelli J, Lefèvre G, Sobanski V, et al. Altered b lymphocyte homeostasis and functions in systemic sclerosis. *Autoimmun Rev* (2018) 17:244-55. doi: 10.1016/j.autrev.2017.10.015

11. Du AX, Gniadecki R, Osman M. Biomarkers of b cell activation in autoimmune connective tissue diseases: More than markers of disease activity. *Clin Biochem* (2022) 100:1-12. doi: 10.1016/j.clinbiochem.2021.11.009

12. Salazar-Camarena DC, Ortiz-Lazareno PC, Cruz A, Oregon-Romero E, Machado-Contreras JR, Muñoz-Valle JF, et al. Association of BAFF, APRIL serum levels, BAFF-r, TACI and BCMA expression on peripheral b-cell subsets with clinical manifestations in systemic lupus erythematosus. *Lupus* (2016) 25:582-92. doi: 10.1177/0961203315608254

13. Laurent SA, Hoffmann FS, Kuhn P-H, Cheng Q, Chu Y, Schmidt-Supprian M, et al. γ-secretase directly sheds the survival receptor BCMA from plasma cells. *Nat Commun* (2015) 6:7333. doi: 10.1038/ncomms8333

14. Hoffmann FS, Kuhn P-H, Laurent SA, Hauck SM, Berer K, Wendlinger SA, et al. The immunoregulator soluble TACI is released by ADAM10 and reflects b cell activation in autoimmunity. *J Immunol* (2015) 194:542-52. doi: 10.4049/jimmunol.1402070

15. Hegazy M, Darwish H, Darweesh H, El-Shehaby A, Emad Y. Raised serum level of APRIL in patients with systemic lupus erythematosus: correlations with disease activity indices. *Clin Immunol Orlando Fla* (2010) 135:118-24. doi: 10.1016/j.clim.2009.12.012

16. Morel J, Roubille C, Panelles L, Rocha C, Fernandez L, Lukas C, et al. Serum levels of tumour necrosis factor family members a proliferation-inducing ligand (APRIL) and b lymphocyte stimulator (BLyS) are inversely correlated in systemic lupus erythematosus. *Ann Rheum Dis* (2009) 68:997-1002. doi: 10.1136/ard.2008.090928

17. Koyama T, Tsukamoto H, Miyagi Y, Himeji D, Otsuka J, Miyagawa H, et al. Raised serum APRIL levels in patients with systemic lupus erythematosus. *Ann Rheum Dis* (2005) 64:1065-7. doi: 10.1136/ard.2004.022491

18. Treamtrakapon W, Tantivitayakul P, Benjachat T, Somparn P, Kittikowit W, Eiam-ong S, et al. APRIL, a proliferation-inducing ligand, as a potential marker of lupus nephritis. *Arthritis Res Ther* (2012) 14:R252. doi: 10.1186/ar4095

19. Breen EC, Hussain SK, Magpantay L, Jacobson LP, Detels R, Rabkin CS, et al. B-cell stimulatory cytokines and markers of immune activation are elevated several years prior to the diagnosis of systemic AIDS-associated non-Hodgkin b-cell lymphoma. *Cancer Epidemiol Biomarkers Prev* (2011) 20:1303-14. doi: 10.1158/1055-9965.EPI-11-0037

20. De Roos AJ, Mirick DK, Edlefsen KL, LaCroix AZ, Kopecky KJ, Madeleine MM, et al. Markers of b-cell activation in relation to risk of non-Hodgkin lymphoma. *Cancer Res* (2012) 72:4733-43. doi: 10.1158/0008-5472.CAN-12-1639

21. Monach PA, Warner RL, Tomasson G, Specks U, Stone JH, Ding L, et al. Serum proteins reflecting inflammation, injury and repair as biomarkers of disease activity in ANCA-associated vasculitis. *Ann Rheum Dis* (2013) 72:1342-50. doi: 10.1136/annrheumdis-2012-201981

22. Land J, Abdulahad WH, Sanders J-SF, Stegeman CA, Heeringa P, Rutgers A. Regulatory and effector b cell cytokine production in patients with relapsing granulomatosis with polyangiitis. *Arthritis Res Ther* (2016) 18:84. doi: 10.1186/s13075-016-0978-1

23. Nocturne G, Seror R, Fogel O, Belkhir R, Boudaoud S, Saraux A, et al. CXCL13 and CCL11 serum levels and lymphoma and disease activity in primary sjögren's syndrome. *Arthritis Rheumatol Hoboken NJ* (2015) 67:3226-33. doi: 10.1002/art.39315

24. Jones JD, Hamilton BJ, Challener GJ, de Brum-Fernandes AJ, Cossette P, Liang P, et al. Serum c-X-C motif chemokine 13 is elevated in early and established rheumatoid arthritis and correlates with rheumatoid factor levels. *Arthritis Res Ther* (2014) 16:R103. doi: 10.1186/ar4552

25. Hafez SS, Saad WES, Shedid NH. B-cell-attracting chemokine-1 (BCA-1/CXCL13) in systemic lupus erythematosus, its correlation to disease activity and renal involvement. *Egypt J Immunol* (2014) 21:23-32.

26. Greisen SR, Schelde KK, Rasmussen TK, Kragstrup TW, Stengaard-Pedersen K, Hetland ML, et al. CXCL13 predicts disease activity in early rheumatoid arthritis and could be an indicator of the therapeutic "window of opportunity." *Arthritis Res Ther* (2014) 16:434. doi: 10.1186/s13075-014-0434-z

27. Lanteri A, Sobanski V, Langlois C, Lefèvre G, Hauspie C, Sanges S, et al. Serum free light chains of immunoglobulins as biomarkers for systemic sclerosis characteristics, activity and severity. *Autoimmun Rev* (2014) 13:974-80. doi: 10.1016/j.autrev.2014.07.003

28. Bassyouni IH, Azab NA, El-Dakrony E-HM, Fawzi MMT, Ghanoum R, Bassyouni RH. Elevated serum levels of a proliferation-inducing ligand in patients with systemic sclerosis: Possible association with myositis? *Joint Bone Spine* (2011) 78:56-61. doi: 10.1016/j.jbspin.2010.05.004

29. Matsushita T, Fujimoto M, Hasegawa M, Tanaka C, Kumada S, Ogawa F, et al. Elevated serum APRIL levels in patients with systemic sclerosis: distinct profiles of systemic sclerosis categorized by APRIL and BAFF. *J Rheumatol* (2007) 34:2056-62.

30. Pagano L, Paletti S, Afa G, Marra R, Garcovich A, Bizzi B. Serum beta 2-microglobulin in systemic sclerosis. *Clin Rheumatol* (1985) 4:286-9. doi: 10.1007/BF02031609

31. Minh VN, Hau KT, Takashi M, Ha VN, Bao LH, Huyen ML, et al. Efficacy of BAFF in monitoring treatment response in early Vietnamese systemic sclerosis patients. *Open Access Maced J Med Sci* (2019) 7:264-8. doi: 10.3889/oamjms.2019.070

32. Bosello S, Basile U, De Lorenzis E, Gulli F, Canestrari G, Napodano C, et al. Free light chains of immunoglobulins in patients with systemic sclerosis: correlations with lung involvement and inflammatory milieu. *J Clin Pathol* (2018) 71:620-5. doi: 10.1136/jclinpath-2017-204656

33. Wutte N, Kovacs G, Berghold A, Reiter H, Aberer W, Aberer E. CXCL13 and b-cell activating factor as putative biomarkers in systemic sclerosis. *Br J Dermatol* (2013) 169:723-5. doi: 10.1111/bjd.12411

34. Abdo MS, Mohammed RHA, Raslan HM, Gaber SM. Serum b-cell activating factor assessment in a population of Egyptian patients with systemic sclerosis. *Int J Rheum Dis* (2013) 16:148-56. doi: 10.1111/1756-185x.12019

35. Fawzy SM, Gheita TA, El-Nabarawy E, El-Demellawy HH, Shaker OG. Serum BAFF level and its correlations with various disease parameters in patients with systemic sclerosis and systemic lupus erythematosus. *Egypt Rheumatol* (2011) 33:45-51. doi: 10.1016/j.ejr.2010.12.001

36. Matsushita T, Hasegawa M, Yanaba K, Kodera M, Takehara K, Sato S. Elevated serum BAFF levels in patients with systemic sclerosis: Enhanced BAFF signaling in systemic sclerosis b lymphocytes. *Arthritis Rheum* (2006) 54:192-201. doi: 10.1002/art.21526

37. Taniguchi T, Miyagawa T, Toyama S, Yamashita T, Nakamura K, Saigusa R, et al. CXCL13 produced by macrophages due to Fli1 deficiency may contribute to the development of tissue fibrosis, vasculopathy and immune activation in systemic sclerosis. *Exp Dermatol* (2018) 27:1030-7. doi: 10.1111/exd.13724

38. Zhang H, Li P, Wu D, Xu D, Hou Y, Wang Q, et al. Serum IgG subclasses in autoimmune diseases. *Med (Baltimore)* (2015) 94:e387. doi: 10.1097/MD.0000000000000387
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66. Wielosz E, Majdan M, Dryglewska M, Targońska-Stepniak B. Overlap syndromes in systemic sclerosis. *Adv Dermatol Allergol* (2018) 35:246–50. doi: 10.5114/ada.2018.72662

67. Moinzadeh P, Aberer E, Ahmadi-Simab K, Blank N, Distler JHW, Fierlbeck G, et al. Disease progression in systemic sclerosis-overlap syndrome is significantly different from limited and diffuse cutaneous systemic sclerosis. *Ann Rheum Dis* (2015) 74:730–7. doi: 10.1136/annrheumdis-2013-204487

68. Balbir-Gurman A, Braun-Moscovici Y. Scleroderma overlap syndrome *Isr Med Assoc J* (2011) 13:14–20.

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70. Negi VS, Tripathy NK, Misra R, Nityanand S. Antiendothelial cell antibodies in scleroderma correlate with severe digital ischemia and pulmonary arterial hypertension. *J Rheumatol* (1998) 25:462–6.

71. Pignone A, Scaletti C, Matucci-Cerinic M, Vázquez-Abad D, Meroni PL, Del Papa N, et al. Anti-endothelial cell antibodies in systemic sclerosis: significant association with vascular involvement and alveo-lo-capillary impairment. *Clin Exp Rheumatol* (1998) 16:527–32. doi: 10.1128/cdli.6.2.156-160.1999

72. Ihn H, Sato S, Fujimoto M, Igarashi A, Yazawa N, Kubo M, et al. Characterization of autoantibodies to endothelial cells in systemic sclerosis (SSc): association with pulmonary fibrosis. *Clin Exp Immunol* (2000) 119:203–9. doi: 10.1046/j.1365-2249.2000.01115.x

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75. Riccieri V, Germano V, Alessandri C, Vasile M, Ceccarelli F, Sciarra I, et al. More severe nailfold capillaroscopy findings and anti-endothelial cell antibodies. are they useful tools for prognostic use in systemic sclerosis? *Clin Exp Rheumatol* (2008) 26:992–7.

76. Riemekasten G, Philippe A, Näther M, Slowinski T, Müller DN, Heidecke H, et al. Involvement of functional autoantibodies against vascular receptors in systemic sclerosis. *Ann Rheum Dis* (2011) 70:530–6. doi: 10.1136/ard.2010.135772

77. Becker MO, Kill A, Kutsche M, Guenther J, Rose A, Tabeling C, et al. Vascular receptor autoantibodies in pulmonary arterial hypertension associated with systemic sclerosis. *Am J Respir Crit Care Med* (2014) 190:808–17. doi: 10.1164/rccm.201403-0442OC

78. Günther J, Kill A, Becker MO, Heidecke H, Rademacher J, Siegert E, et al. Angiotensin receptor type 1 and endothelin receptor type a on immune cells mediate migration and the expression of IL-8 and CCL18 when stimulated by autoantibodies from systemic sclerosis patients. *Arthritis Res Ther* (2014) 16:R65. doi: 10.1186/ar4503

79. Kill A, Tabeling C, Undeutsch R, Kühl AA, Günther J, Radic M, et al. Autoantibodies to angiotensin and endothelin receptors in systemic sclerosis induce cellular and systemic events associated with disease pathogenesis. *Arthritis Res Ther* (2014) 16:R29. doi: 10.1186/ar4457

80. Avouac J, Riemekasten G, Meune C, Ruiz B, Kahan A, Allanore Y. Autoantibodies against endothelin 1 type a receptor are strong predictors of digital ulcers in systemic sclerosis. *J Rheumatol* (2015) 42:1801–7. doi: 10.3899/jrheum.150061

81. Jin R, Kaneko H, Suzuki H, Arai T, Teramoto T, Fukao T, et al. Age-related changes in BAFF and APRIL profiles and upregulation of BAFF and APRIL expression in patients with primary antibody deficiency. *Int J Mol Med* (2008) 21:233-238. doi: 10.3892/ijmm.21.2.233
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61. Valentini G, Rossa AD, Bombardieri S, Bencivelli W, Silman AJ, D'Angelo S, et al. European Multicentre study to define disease activity criteria for systemic sclerosis. *Ann Rheum Dis* (2001) 60:592-8. doi: 10.1136/ard.60.6.592

62. Medsger TA, Bombardieri S, Czirjak L, Scorza R, Rossa AD, Bencivelli W. Assessment of disease severity and prognosis in systemic sclerosis. *Clin Exp Rheumatol* (2003) 21:S42-6.

63. Georges C, Chassany O, Mouthon L, Tiev K, Toledano C, Meyer O, et al. Validation of French version of the scleroderma health assessment questionnaire (SSc HAQ). *Clin Rheumatol* (2005) 24:3-10. doi: 10.1007/s10067-004-0942-3

64. Cohen J. Eta-squared and partial eta-squared in fixed factor anova designs. *Educ Psychol Meas* (1973) 33:107-12. doi: 10.1177/001316447303300111

65. Scherlinger M, Lutz J, Galli G, Richez C, Gottenberg J-E, Sibilia J, et al. Systemic sclerosis overlap and non-overlap syndromes share clinical characteristics but differ in prognosis and treatments. *Semin Arthritis Rheum* (2021) 51:36-42. doi: 10.1016/j.searthrit.2020.10.009

66. Wielosz E, Majdan M, Dryglewska M, Targońska-Stepniak B. Overlap syndromes in systemic sclerosis. *Adv Dermatol Allergol* (2018) 35:246-50. doi: 10.5114/ada.2018.72662

67. Moinzadeh P, Aberer E, Ahmadi-Simab K, Blank N, Distler JHW, Fierlbeck G, et al. Disease progression in systemic sclerosis-overlap syndrome is significantly different from limited and diffuse cutaneous systemic sclerosis. *Ann Rheum Dis* (2015) 74:730-7. doi: 10.1136/annrheumdis-2013-204487

68. Balbir-Gurman A, Braun-Moscovici Y. Scleroderma overlap syndrome *Isr Med Assoc J* (2011) 13:14-20.

69. Hebbar M, Lassalle P, Delneste Y, Hatron PY, Devulder B, Tonnel AB, et al. Assessment of anti-endothelial cell antibodies in systemic sclerosis and sjögren's syndrome. *Ann Rheum Dis* (1997) 56:230-4. doi: 10.1136/ard.56.4.230

70. Negi VS, Tripathy NK, Misra R, Nityanand S. Antiendothelial cell antibodies in scleroderma correlate with severe digital ischemia and pulmonary arterial hypertension. *J Rheumatol* (1998) 25:462-6.

71. Pignone A, Scaletti C, Matucci-Cerinic M, Vázquez-Abad D, Meroni PL, Del Papa N, et al. Anti-endothelial cell antibodies in systemic sclerosis: significant association with vascular involvement and alveo-lo-capillary impairment. *Clin Exp Rheumatol* (1998) 16:527-32. doi: 10.1128/cdli.6.2.156-160.1999

72. Ihn H, Sato S, Fujimoto M, Igarashi A, Yazawa N, Kubo M, et al. Characterization of autoantibodies to endothelial cells in systemic sclerosis (SSc): association with pulmonary fibrosis. *Clin Exp Immunol* (2000) 119:203-9. doi: 10.1046/j.1365-2249.2000.01115.x

73. Wusirika R, Ferri C, Marin M, Knight DA, Waldman WJ, Ross P, et al. The assessment of anti-endothelial cell antibodies in scleroderma-associated pulmonary fibrosis. *Am J Clin Pathol* (2003) 120:596-606. doi: 10.1309/8HVMCMJMYNPUQBPD2

74. Tamby MC. Anti-endothelial cell antibodies in idiopathic and systemic sclerosis associated pulmonary arterial hypertension. *Thorax* (2005) 60:765-72. doi: 10.1136/thx.2004.029082

75. Riccieri V, Germano V, Alessandri C, Vasile M, Ceccarelli F, Sciarra I, et al. More severe nailfold capillaroscopy findings and anti-endothelial cell antibodies. are they useful tools for prognostic use in systemic sclerosis? *Clin Exp Rheumatol* (2008) 26:992-7.

76. Riemekasten G, Philippe A, Näther M, Slowinski T, Müller DN, Heidecke H, et al. Involvement of functional autoantibodies against vascular receptors in systemic sclerosis. *Ann Rheum Dis* (2011) 70:530-6. doi: 10.1136/ard.2010.135772

77. Becker MO, Kill A, Kutsche M, Guenther J, Rose A, Tabeling C, et al. Vascular receptor autoantibodies in pulmonary arterial hypertension associated with systemic sclerosis. *Am J Respir Crit Care Med* (2014) 190:808-17. doi: 10.1164/rccm.201403-0442OC

78. Günther J, Kill A, Becker MO, Heidecke H, Rademacher J, Siegert E, et al. Angiotensin receptor type 1 and endothelin receptor type a on immune cells mediate migration and the expression of IL-8 and CCL18 when stimulated by autoantibodies from systemic sclerosis patients. *Arthritis Res Ther* (2014) 16:R65. doi: 10.1186/ar4503

79. Kill A, Tabeling C, Undeutsch R, Kühl AA, Günther J, Radic M, et al. Autoantibodies to angiotensin and endothelin receptors in systemic sclerosis induce cellular and systemic events associated with disease pathogenesis. *Arthritis Res Ther* (2014) 16:R29. doi: 10.1186/ar4457

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81. Jin R, Kaneko H, Suzuki H, Arai T, Teramoto T, Fukao T, et al. Age-related changes in BAFF and APRIL profiles and upregulation of BAFF and APRIL expression in patients with primary antibody deficiency. *Int J Mol Med* (2008) 21:233-238. doi: 10.3892/ijmm.21.2.233
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© 2022 Sanges, Guerrier, Duhamel, Guilbert, Hauspie, Largy, Balden, Podevin, Lefèvre, Jendoubi, Speca, Hachulla, Sobanski, Dubucquoi and Launay. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author (s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
82. Zollars E, Bienkowska J, Czerkowicz J, Allaire N, Ranger AM, Magder L, et al. BAFF (B cell activating factor) transcript level in peripheral blood of patients with SLE is associated with same-day disease activity as well as global activity over the next year. *Lupus Sci Med* (2015) 2:e000063–e000063. doi: 10.1136/lupus-2014-000063

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