Molecular Vision 2012; 18:512-518 <>
Received 1 December 2011 | Accepted 22 February 2012 | Published 25 January 2012

Lack of association between IL10 polymorphisms and sarcoidosis in Japanese patients

Kenichi Sakuyama,1 Akira Meguro,1 Masao Ota,2 Mami Ishihara,1 Riyo Uemoto,1 Haruyasu Ito,1 Eiichi Okada,3 Kenichi Namba,4 Nobuyoshi Kitaichi,5 Shin-ichiro Morimoto,6 Toshikatsu Kaburaki,7 Yasutaka Ando,8, 9 Shinobu Takenaka,10 Takenosuke Yuasa,11 Shigeaki Ohno,12 Hidetoshi Inoko,13 Nobuhisa Mizuki1

1Department of Ophthalmology and Visual Science, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, Japan; 2Department of Legal Medicine, Shinshu University School of Medicine, Matsumoto, Nagano, Japan; 3Okada Eye Clinic, Yokohama, Kanagawa, Japan; 4Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan; 5Department of Ophthalmology, Health Sciences University of Hokkaido, Sapporo, Hokkaido, Japan; 6Division of Cardiology, Department of Internal Medicine, Fujita Health University School of Medicine, Toyoake, Aichi, Japan; 7Department of Ophthalmology, University of Tokyo School of Medicine, Bunkyo-ku, Tokyo, Japan; 8Department of Ophthalmology, Kitasato Institute Hospital, Minato-ku, Tokyo, Japan; 9Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan; 10Department of Respiratory Diseases, Kumamoto City Hospital, Kumamoto, Kumamoto, Japan; 11Yuasa Eye Clinic, Osaka, Japan; 12Department of Ocular Inflammation and Immunology, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan; 13Department of Molecular Life Science, Division of Molecular Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara, Kanagawa, Japan

Correspondence to: Kenichi Sakuyama, Department of Ophthalmology and Visual Science, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004, Japan; Phone: +81-45-787-2683; FAX: +81-45-781-9755; email: or


Purpose: To investigate whether interleukin 10 (IL10) gene polymorphisms are associated with the development of sarcoidosis in Japanese patients.

Methods: Two hundred and eighty-eight Japanese sarcoidosis patients and 310 Japanese healthy controls were recruited. We genotyped 9 single-nucleotide polymorphisms in IL10 and assessed the allelic diversity between cases and controls.

Results: No significant differences in the frequency of IL10 alleles, genotypes, and haplotypes in the sarcoidosis cases compared to the controls were detected.

Conclusions: Our results suggest that IL10 polymorphisms are not significantly related to the pathogenesis of sarcoidosis in the Japanese population.


Sarcoidosis is a systemic inflammatory disorder characterized by non-caseating granuloma formation in many organs, such as: lung, skin, eye, lymph nodes, central and peripheral nervous system, and heart [1-3].

In Japan, the reported incidence rate of the disease is 1.01 per 100,000 inhabitants [4]. On a global scale, this incidence rate is low. African Americans incidence rate of the disease is 35.5 per 100,000. That of Caucasian Americans is 10.9 per 100,000 [5]. Japanese patients have a higher likelihood of ocular involvement compared with other ethnic groups [4,6]. According to a recent epidemiological study of sarcoidosis in Japan, patients with ocular involvement was 54.8% of cases and impaired vision was the most frequent symptom (28.8%) [4]. In European patients, erythema nodosum of skin lesions is commonly seen. It is rare in Japanese patients [7]. This way, the frequency and course of sarcoidosis varies widely among racial groups. It supports the assumption that some predisposing genetic factors play roles in the development of the disease. There is also evidence supporting a possibility of association with genetic factors. Some familial sarcoidosis cases [8], and associations between the disease and human leukocyte antigen (HLA) systems were reported [9,10]. The exact cause of the disease remains undetermined, but it is currently thought that genetic factors may be the basis of disease susceptibility.

It is also thought that environmental factors associate with the disease progression. By using polymerase-chain-reaction (PCR) techniques, Mycobacterium tuberculosis and Propionibacterium acnes DNA have been detected in sarcoid lesions [11-14]. Recent studies have shown that serum samples from sarcoidosis patients contain antibodies against mycobacterium antigens [15].These studies suggest that immune responses to bacterial infections can affect the development of sarcoidosis.

The inflammatory response in sarcoidosis is characterized by the increased production of several inflammatory cytokines produced by type 1 helper T (Th1) cells and macrophages, such as interleukin-2 (IL-2), interferon-gamma (IFN-γ), and tumor necrosis factor alpha (TNF-α) [16-18]. These cytokines seem to play a roll leading to the formation of granuloma [3]. In some of sarcoidosis patients, the granulomatous response resolves, and the remaining patients have chronic disease include fibrosis. Interleukin-10 (IL-10) produced by type 2 helper T (Th2) cells is associated with the resolution [3]. IL-10 is a potent suppressor of these inflammatory cytokines [19]. Several studies reported that changes in cytokine production might have been caused by a genetic polymorphisms and some of them might be involved in disease susceptibility and progression. Recent studies have reported that IL10 polymorphisms were associated with several inflammatory diseases [20-22]. In the present study, we evaluated the association of multiple SNPs in IL10 in Japanese sarcoidosis patients.



Two hundred and eighty-eight unrelated patients with a diagnosis of sarcoidosis and 310 healthy controls were recruited from Yokohama City University, Hokkaido University, Fujita Health University, Tokyo University, Keio University, Kumamoto City hospital and Yuasa eye clinic. All patients and control participants were of Japanese ethnicity. Sarcoidosis patients were diagnosed according to the diagnostic criteria developed by the Japanese Society of Sarcoidosis and Other Granulomatous Disorders (JSSOG) previously described [23]. Uveitis with sarcoidosis was assessed based on the “Guidelines for Diagnosis of Ocular Lesions in Sarcoidosis” prepared by the JSSOG. The ocular features of sarcoidosis were defined as granulomatous uveitis plus two or more of the following: infiltration of the anterior chamber (mutton-fat keratic precipitates/iris nodules), trabecular meshwork nodules and/or tent-shaped peripheral anterior synechia, masses of vitreous opacities (snowball-like or string of pearls-like appearance), periphlebitis with perivascular nodules; multiple candle-wax type chorioretinal exudates and nodules, and/or laser photocoagulation spot-like chorioretinal atrophy. All subjects had a similar social background and resided in the same urban area. The research methods were in compliance with the guidelines of the Declaration of Helsinki. Details of the study were explained to all patients and controls, and valid consent for genetic screening was obtained.

IL10 genotyping

Peripheral blood lymphocytes were collected, and genomic DNA was extracted from peripheral blood cells using the QIAamp DNA Blood Maxi Kit (Qiagen, Tokyo, Japan). We selected IL10 SNPs which previously showed a significant association with Japanese Behcet’s disease [22]: rs1878672, rs1554286, rs1518111, rs3021094, rs3790622, rs3024490, rs1800872, rs1800871, and rs1800896 (Figure 1, Table 1). Genotyping of all SNPs was performed using the TaqMan 5′exonuclease assay using primers supplied by Applied Biosystems (Foster City, CA). Probe fluorescence signals were detected by TaqMan Assay for real-time PCR (7500 Real Time PCR System; Applied Biosystems) following the manufacturer’s instructions.

Statistical analysis

Hardy–Weinberg equilibrium was tested for each SNP among the controls. Differences in allele and genotype frequencies between cases and controls were assessed by the χ2 test. The Haploview 4.1 program was used to compute pair-wise linkage disequilibrium (LD) statistics [24]. Standardized disequilibrium D’ value and r2 value were plotted, and LD blocks were defined according to the criteria [25]. Haplotype frequencies were estimated with an accelerated expectation-maximization algorithm, similar to the partition-ligation-expectation-maximization method described previously [26]. P values <0.05 were considered statistically significant.


We genotyped nine common SNPs in IL10: rs1878672, rs1554286, rs1518111, rs3021094, rs3790622, rs3024490, rs1800872, rs1800871, and rs1800896. All SNPs were in Hardy–Weinberg equilibrium in the controls (data not shown). All 9 SNPs were located in 1 haplotype block, and the magnitude of LD between each SNP was extremely high, with pair-wise D’≥0.83 (Figure 1). The allele and genotype frequencies of the 9 SNPs in both the cases and controls are listed in Table 1 and Table2, respectively. No statistically significant association was observed for any of the SNPs between the cases and controls. Furthermore, there were no significant differences in the haplotype frequencies of all 9 SNPs between the cases and controls (Table 3). We analyzed clinical features according to 9 SNPs. In a stratified analysis according to lesion location, which included the eye, lungs, skin heart, and nerves, none of these clinical features were found to be significantly associated with 9 SNPs (data not shown).


The aim of the current study was to investigate whether IL10 polymorphisms affect the development of Japanese patients with sarcoidosis. Our results showed that all the IL10 polymorphisms were not significantly associated with any clinical subtype of sarcoidosis including ocular involvement in Japanese patients. Here we report a lack of association between IL10 variants and Japanese sarcoidosis patients, suggesting that the possibility of attributing the pathogenesis of sarcoidosis to IL10 genetic variations is low.

IL-10 poroduced by Th2 cells suppresses inflammatory cytokines produced by Th1 cells. Although the mechanism of IL-10 in sarcoidosis is unclear, it is thought to be associated with granuloma resolution [2,3]. Some studies have reported that serum levels of IL-10 were increased in several inflammatory diseases, such as; Crohn’s disease, diffuse cutaneous systemic sclerosis and active Behçet's disease [27-29]. In addition, increased serum levels of IL-10 in sarcoidosis patients have been reported [30,31].

Recent studies have also reported that IL10 gene polymorphisms were associated with several inflammatory diseases. Wang et al. [20] reported IL-10 concentration was significantly higher in Crohn’s disease patients than in the controls and IL10 polymorphisms were associated with increased patient serum IL-10 levels. Hudson et al. [21] reported that IL10 genotypes were associated with systemic sclerosis-related autoantibodies and contribute to the etiology of systemic sclerosis. Recently, Mizuki et al. [22] performed a genome-wide association study for Behect’s disease and identified IL10 as a disease susceptibility gene. Muraközy et al. [32] investigated an association of IL10 polymorphisms with sarcoidosis, however they could not find any significant differences. As with the previous report, we could not find any association between IL10 gene polymorphisms and sarcoidosis. On the other hand, Vasakova et al. [33] have recently shown that there are significant differences in the frequencies of IL10 polymorphisms between sarcoidosis and healthy controls in the Czech Caucasian population, whereas they suggested that their findings cannot be generalized since the sample size in the study was small.

In summary, the IL10 polymorphisms do not appear to be significantly relevant to Japanese sarcoidosis patients. However, further genetic studies in other ethnic populations are required to elucidate the association between IL10 polymorphisms and sarcoidosis.


We sincerely thank all the participants in this study. We thank Tomoko Shiota for technical assistance. We also thank all of the staff and doctors who contributed to blood sample collection from the subjects.


  1. Newman LS, Rose CS, Maier LA. Sarcoidosis. N Engl J Med. 1997; 336:1224-34. [PMID: 9110911]
  2. Baughman RP, Lower EE, du Bois RM. Sarcoidosis. Lancet. 2003; 361:1111-8. [PMID: 12672326]
  3. Iannuzzi MC, Rybicki BA, Teirstein AS. Sarcoidosis. N Engl J Med. 2007; 357:2153-65. [PMID: 18032765]
  4. Morimoto T, Azuma A, Abe S, Usuki J, Kudoh S, Sugisaki K, Oritsu M, Nukiwa T. Epidemiology of sarcoidosis in Japan. Eur Respir J. 2008; 31:372-9. [PMID: 17959635]
  5. Rybicki BA, Major M, Popovich J Jr, Maliarik MJ, Iannuzzi MC. Racial differences in sarcoidosis incidence: a 5-year study in a health maintenance organization. Am J Epidemiol. 1997; 145:234-41. [PMID: 9012596]
  6. ACCESS Research Group. Design of a case control etiologic study of sarcoidosis (ACCESS). J Clin Epidemiol. 1999; 52:1173-86. [PMID: 10580780]
  7. Statement on sarcoidosis. Joint Statement of the American Thoracic Society (ATS), the European Respiratory Society (ERS) and the World Association of Sarcoidosis and Other Granulomatous Disorders (WASOG) adopted by the ATS Board of Directors and by the ERS Executive Committee, February 1999. Am J Respir Crit Care Med. 1999; 160:736-55. [PMID: 10430755]
  8. Rybicki BA, Iannuzzi MC, Frederick MM, Thompson BW, Rossman MD, Bresnitz EA, Terrin ML, Moller DR, Barnard J, Baughman RP, DePalo L, Hunninghake G, Johns C, Judson MA, Knatterud GL, McLennan G, Newman LS, Rabin DL, Rose C, Teirstein AS, Weinberger SE, Yeager H, Cherniack R, ACCESS Research Group. Familial aggregation of sarcoidosis: A Case-Control Etiologic Study of Sarcoidosis (ACCESS). Am J Respir Crit Care Med. 2001; 164:2085-91. [PMID: 11739139]
  9. Kunikane H, Abe S, Tsuneta Y, Nakayama T, Tajima Y, Misonou J, Wakisaka A, Aizawa M, Kawakami Y. Role of HLA-DR antigens in Japanese patients with sarcoidosis. Am Rev Respir Dis. 1987; 135:688-91. [PMID: 3826893]
  10. Ishihara M, Ohno S, Ishida T, Kagiya M, Ando H, Inoko H. Analysis of susceptibility genes in sarcoidosis. Nihon Ganka Gakkai Zasshi. 1994; 98:80-5. [PMID: 8109450]
  11. Abe C, Iwai K, Mikami R, Hosoda Y. Frequent isolation of Propionibacterium acnes from sarcoidosis lymph nodes. Zentralbl Bakteriol Mikrobiol Hyg A. 1984; 256:541-7. [PMID: 6377763]
  12. Saboor SA, Johnson NM, McFadden J. Detection of mycobacterial DNA in sarcoidosis and tuberculosis with polymerase chain reaction. Lancet. 1992; 339:1012-5. [PMID: 1349051]
  13. Ishige I, Usui Y, Takemura T, Eishi Y. Quantitative PCR of mycobacterial and propionibacterial DNA in lymph nodes of Japanese patients with sarcoidosis. Lancet. 1999; 354:120-3. [PMID: 10408488]
  14. Eishi Y, Suga M, Ishige I, Kobayashi D, Yamada T, Takemura T, Takizawa T, Koike M, Kudoh S, Costabel U, Guzman J, Rizzato G, Gambacorta M, du Bois R, Nicholson AG, Sharma OP, Ando M. Quantitative analysis of mycobacterial and propionibacterial DNA in lymph nodes of Japanese and European patients with sarcoidosis. J Clin Microbiol. 2002; 40:198-204. [PMID: 11773116]
  15. Dubaniewicz A, Kämpfer S, Singh M. Serum anti-mycobacterial heat shock proteins antibodies in sarcoidosis and tuberculosis. Tuberculosis (Edinb). 2006; 86:60-7. [PMID: 16352470]
  16. Konishi K, Moller DR, Saltini C, Kirby M, Crystal RG. Spontaneous expression of the interleukin 2 receptor gene and presence of functional interleukin 2 receptors on T lymphocytes in the blood of individuals with active pulmonary sarcoidosis. J Clin Invest. 1988; 82:775-81. [PMID: 3138285]
  17. Robinson BW, McLemore TL, Crystal RG. Gamma interferon is spontaneously released by alveolar macrophages and lung T lymphocytes in patients with pulmonary sarcoidosis. J Clin Invest. 1985; 75:1488-95. [PMID: 3923038]
  18. Baughman RP, Strohofer SA, Buchsbaum J, Lower EE. Release of tumor necrosis factor by alveolar macrophages of patients with sarcoidosis. J Lab Clin Med. 1990; 115:36-42. [PMID: 2299255]
  19. Bingisser R, Speich R, Zollinger A, Russi E, Frei K. Interleukin-10 secretion by alveolar macrophages and monocytes in sarcoidosis. Respiration. 2000; 67:280-6. [PMID: 10867596]
  20. Wang AH, Lam WJ, Han DY, Ding Y, Hu R, Fraser AG, Ferguson LR, Morgan AR. The effect of IL-10 genetic variation and interleukin 10 serum levels on Crohn's disease susceptibility in a New Zealand population. Hum Immunol. 2011; 72:431-5. [PMID: 21354456]
  21. Hudson LL, Rocca KM, Kuwana M, Pandey JP. Interleukin-10 genotypes are associated with systemic sclerosis and influence disease-associated autoimmune responses. Genes Immun. 2005; 6:274-8. [PMID: 15772682]
  22. Mizuki N, Meguro A, Ota M, Ohno S, Shiota T, Kawagoe T, Ito N, Kera J, Okada E, Yatsu K, Song YW, Lee EB, Kitaichi N, Namba K, Horie Y, Takeno M, Sugita S, Mochizuki M, Bahram S, Ishigatsubo Y, Inoko H. Genome-wide association studies identify IL23R–IL12RB2 and IL10 as Behçet's disease susceptibility loci. Nat Genet. 2010; 42:703-6. [PMID: 20622879]
  23. Asukata Y, Ota M, Meguro A, Katsuyama Y, Ishihara M, Namba K, Kitaichi N, Morimoto S, Kaburaki T, Ando Y, Takenaka S, Inoko H, Ohno S, Mizuki N. Lack of association between toll-like receptor 4 gene polymorphisms and sarcoidosis-related uveitis in Japan. Mol Vis. 2009; 15:2673-82. [PMID: 20011079]
  24. Barrett JC, Fry B, Maller J, Daly MJ. Haploview: analysis and visualization of LD and haplotype maps. Bioinformatics. 2005; 21:263-5. [PMID: 15297300]
  25. Gabriel SB, Schaffner SF, Nguyen H, Moore JM, Roy J, Blumenstiel B, Higgins J, DeFelice M, Lochner A, Faggart M, Liu-Cordero SN, Rotimi C, Adeyemo A, Cooper R, Ward R, Lander ES, Daly MJ, Altshuler D. The structure of haplotype blocks in the human genome. Science. 2002; 296:2225-9. [PMID: 12029063]
  26. Qin ZS, Niu T, Liu J. Partition-ligation-expectation-maximization algorithm for haplotype inference with single-nucleotide polymorphisms. Am J Hum Genet. 2002; 71:1242-7. [PMID: 12452179]
  27. Kucharzik T, Stoll R, Lügering N, Domschke W. Circulating antiinflammatory cytokine IL-10 in patients with inflammatory bowel disease (IBD). Clin Exp Immunol. 1995; 100:452-6. [PMID: 7774055]
  28. Hasegawa M, Fujimoto M, Kikuchi K, Takehara K. Elevated serum levels of interleukin 4 (IL-4), IL-10, and IL-13 in patients with systemic sclerosis. J Rheumatol. 1997; 24:328-32. [PMID: 9034992]
  29. Hamzaoui K, Hamzaoui A, Guemira F, Bessioud M, Hamza M, Ayed K. Cytokine profile in Behçet's disease patients. Relationship with disease activity. Scand J Rheumatol. 2002; 31:205-10. [PMID: 12369651]
  30. Fuse K, Kodama M, Okura Y, Ito M, Aoki Y, Hirono S, Kato K, Hanawa H, Aizawa Y. Levels of serum interleukin-10 reflect disease activity in patients with cardiac sarcoidosis. Jpn Circ J. 2000; 64:755-9. [PMID: 11059615]
  31. Bansal AS, Bruce J, Hogan PG, Allen RK. An assessment of peripheral immunity in patients with sarcoidosis using measurements of serum vitamin D3, cytokines and soluble CD23. Clin Exp Immunol. 1997; 110:92-7. [PMID: 9353154]
  32. Muraközy G, Gaede KI, Zissel G, Schlaak M, Müller-Quernheim J. Analysis of gene polymorphisms in interleukin-10 and transforming growth factor-beta 1 in sarcoidosis. Sarcoidosis Vasc Diffuse Lung Dis. 2001; 18:165-9. [PMID: 11436536]
  33. Vasakova M, Sterclova M, Kolesar L, Slavcev A, Skibova J, Striz I. Cytokine gene polymorphisms in sarcoidosis. Sarcoidosis Vasc Diffuse Lung Dis. 2010; 27:70-5. [PMID: 21086908]