Skip to main content
NCBI home page
Clinical and Experimental Immunology logoLink to Clinical and Experimental Immunology
. 2015 Feb 16;179(3):520–528. doi: 10.1111/cei.12475

Quantitative T cell subsets profile in peripheral blood from patients with idiopathic inflammatory myopathies: tilting the balance towards proinflammatory and pro-apoptotic subsets

F Espinosa-Ortega 1,1, D Gómez-Martin 1,1, K Santana-De Anda 1, J Romo-Tena 1, P Villaseñor-Ovies 1, J Alcocer-Varela 1,✉
PMCID: PMC4337684  PMID: 25348796

Abstract

The role of T cells in idiopathic inflammatory myopathies (IIM) is not yet clear. Some alterations in certain subsets have been reported in inflamed muscle cells. However, a broad quantitative assessment of peripheral T cell subsets has not been evaluated. The aim of this study was to address the quantitative profile of potential pathogenic T cell subsets, namely follicular helper T cells (Tfh), T helper type 17 (Th17), CD28null and regulatory T cells (Tregs) in peripheral blood from IIM patients. Thirty IIM patients and 30 age- and gender-matched healthy donors were included. Peripheral blood mononuclear cells were isolated. T cell subsets were evaluated by flow cytometry, as follows: Tfh (CD4+CXCR5+) and its subsets Tfh1 (CXCR3+CCR6−), Tfh2 (CXCR3−CCR6−), Tfh17 (CXCR3−CCR6+), Th17 (CD4+IL17A+), CD28null (CD4+CD28−CD244+) and Tregs (CD4+CD25highforkhead box protein 3 (FoxP3+); CD8+CD25highFoxP3+). Percentage, absolute numbers and mean fluorescence intensity were analysed. We found increased numbers of total Tfh cells (28 ± 8·16 versus 6·64 ± 1·29, P = 0·031) in IIM patients when compared to healthy controls. Moreover, this increment was dependent upon Tfh2 and Tfh17 (Tfh2:9·49 ± 2·19 versus 1·66 ± 0·46, P = 0·005; Tfh17 9·48 ± 2·83 versus 1·18 ± 0·21, P = 0·014). Also, IIM patients showed higher numbers of Th17 cells (30·25 ± 6·49 versus 13·46 ± 2·95, P = 0·031) as well as decreased number of Tregs (5·98 ± 1·61 versus 30·82 ± 8·38, P = 0·009). We also found an expansion of CD28null cells (162·88 ± 32·29 versus 64 ± 17·35, P = 0·015). Our data suggest that IIM patients are characterized by an expansion of peripheral proinflammatory T cells, such as Tfh and Th17, as well as pro-apoptotic CD28 null cells and a deficiency of suppressor populations of Tregs (CD4+ and CD8+).

Keywords: CD28null cells, idiopathic inflammatory myopathies, regulatory T cells, Tfh cells, Th17 cells

Introduction

Adult idiopathic inflammatory myopathies (IIM) encompass a group of heterogeneous chronic autoimmune diseases that involve the muscle tissue 1. However, skin, lungs and other organs may also been affected. Among the different subtypes of IIM, dermatomyositis (DM) and polymyositis (PM) have the highest incidence rates 2.

Multiple clinical, serological and histopathological features have been described for each subtype and some of them have been proposed for diagnostic and prognostic purposes 3,4.

Histopathologically, muscle cells display cellular infiltrates of lymphocytes (B and T), dendritic cells and macrophages. Electron microscopy studies of inflamed tissue from myositis patients suggest that T cells are directly toxic to muscle tissue; however, the precise pathogenic mechanisms have not been addressed fully 5. Similar to other autoimmune diseases, a type I interferon (IFN) signature has been shown in peripheral blood as well as in muscle tissue from IIM patients 6.

Among the current pathogenic scheme, the role of B cells has been supported since acknowledgement of the association between myositis-specific autoantibodies (MSAs) and clinical features 7, as well as expansion of peripheral plasma cells 8.

As diverse T cell subsets play important roles in providing co-operation to B cells and are able to carry out potential pathogenic effector functions, such as synthesis of proinflammatory cytokines and cytotoxicity, they have been assessed, however, mainly in the involved muscle tissue. In this regard, interleukin (IL)-17 mRNA has been identified in muscle biopsies of patients with polymyositis and dermatomyositis 9. It also has been shown that this cytokine, in combination with IL-1, can induce expression of major histocompatibility (MHC) class I molecules and IL-6 in myoblasts 10. Beyond proinflammatory lymphocytes, regulatory T cells (Tregs), with either predominant suppressor (CD4+) or cytotoxic (CD8+) function, have also been implicated in autoimmune diseases 11. Forkhead box protein 3 (FoxP3+) Tregs have been found close to effector cells in muscle biopsies of IIM patients and related to the inflammatory score 12.

CD28null T cells are among the subpopulations that have been potentially implicated in the pathogenesis of IIM. Their development has been linked to chronic antigenic stimulation, and has been shown to be expanded in muscle infiltrates of IIM patients 13. More recently, follicular helper T cells (Tfh) have gained attention as a newly recognized subset that is able to promote isotype switching and co-operation to B cells in germinal centres 14. Human peripheral chemokine (C-X-C motif) receptor 5 (CXCR5+) CD4+ T cells are considered the equivalents of Tfh cells, and this subset has been found to be increased in juvenile dermatomyositis 15.

Hence, current evidence supports the potential pathogenic role of the aforementioned T cell subsets and the assessment in peripheral blood could be of particular clinical value.

The aim of this study was to address the quantitative profile of potential pathogenic T cell subsets, namely Tfh, Th17, CD28null and Tregs in peripheral blood from IIM patients.

Materials and methods

Patients and healthy controls

Thirty patients with IIM diagnosis according to Peter and Bohan criteria 16 were included in this study. From this group, 20 were diagnosed as dermatomyositis and 10 as polymyositis. Thirty age- and gender-matched healthy controls were included. The patients' mean age was 42 ± 9·8 years. Disease activity was evaluated by two physicians (F.E./K.S.) using the physician's global assessment 17. The study was approved by the Institutional Ethics Committee. All subjects signed informed consent prior to the inclusion in the study.

Flow cytometry

Peripheral blood mononuclear cells (PBMCs) were obtained from inflammatory myopathy patients and healthy controls (HCs) by density-gradient centrifugation (Fycoll-Hypaque). PBMCs were stained with combinations of the following antibodies: anti-CD3 allophycocyanin (APC), anti-CD4 phycoerythrin-cyanin 5 (PE-Cy5), anti-CD28 fluorescein isothiocyanate (FITC), anti-CD244-PE, anti-CD4 FITC, anti-CXCR5-PE-Cy5, anti-CXCR3-PE and anti-CCR6 APC, anti-CD4-FITC, anti-CD25-PE, anti-CD4-peridinin chlorophyll (PerCP) and anti-CD69-PerCP (BD Pharmingen, San Jose, CA, USA). Intracellular staining was performed in freshly isolated PBMCs. After fixation and permeabilization (Cytofix/Cytoperm Kit; BD Biosciences, San Jose, CA, USA), cells were stained with anti-IL-17A-PE (eBiosciences, San Diego, CA, USA) or anti-FoxP3-PE (BD Pharmingen, San Jose, CA, USA). Data were collected on a fluorescence activated cell; sorter (FACS)Canto flow cytometer (BD Biosciences) and analysed using FlowJo (TreeStar Inc., Ashland, OR, USA). The cut-off point for positive staining was set above the level of staining of unstained cells. T cell subsets were defined as follows: CD4 Treg (CD4+, CD25high, FoxP3+), CD8 Treg (CD8+, CD25high, FoxP3+), CD4 CD28null (CD4+, CD28−, CD244+), Th17 (CD4+, IL-17A+) and Thf (CD4+ CXCR5+; CCR6 and CXCR3).

For Th17 cell detection, PBMCs were stimulated with plate-bound anti-CD3 plus anti-CD28 for 1 h and treated with the transport inhibitor monesin, according to the manufacturer's instructions. Frequency (percentage), absolute numbers and mean fluorescence intensity (MFI) were analysed.

Absolute numbers were obtained by multiplying the number of lymphocytes (cells/μl of venous peripheral blood) by the percentage of CD4+ subsets as follows: CD4+CXCR5+ cells for Tfh, CD4+ and IL-17A+ for Th17, CD4+, CD28− and CD244+ for CD28null cells, CD4+ or CD8+CD25+ cells for Tregs.

Briefly, the gating strategies for the different T cell subsets assessed were as follows: (a) for Tfh, we first plotted a gate that included CD4+CXCR5+ cells, and from this gate, we plotted three different gates, based on the expression of CXCR3 and CCR6, as follows: (i) for Tfh1, CXCR3+/CCR6−; (ii) Tfh2: CXCR3−/CCR6−; and (iii) Tfh17: CXCR3−/CCR6+. (b) CD28null cells, we plotted a gate that included CD3+CD4+ cells, and from this gate we plotted another gate that included the CD244+CD28− cells. (c) For Tregs, a gate that included 2% of cells with the highest CD25 expression was set to define the CD25high cells.

Statistical analysis

Results are expressed as the mean ± standard deviation, unless noted otherwise. Differences between groups were analysed using independent-sample Student's t-test. P-values less than 0·05 were considered statistically significant. spss software version 21·0 (SPSS Inc., Chicago, IL, USA) was used for statistical analyses.

Results

Lymphopenia as a clinical feature of active disease in IIM patients

Demographic and clinical characteristics of the thirty IIM patients included in the study are summarized in Table 1. Eighteen patients (60%) had active disease and 12 patients had inactive disease at the time of the blood draw, according to the International Myositis Assessment and Clinical Studies group tools 18. Patients with active untreated IIM showed lower lymphocyte counts in comparison to inactive patients (528 versus 1677 cells/mm3; P = 0·011). No differences were found between disease subtype. Most (70%) of the inactive patients were under immunosuppressive treatment, mainly azathioprine and hydroxychloroquine.

Table 1.

Clinical and demographic features of dermatomyositis and polymiositis patients

Feature Median ± s.d. or proportion
Age (years) 42 ± 9·8
Diagnosis DM/PM 20/10
Time since diagnosis (years) 4·8 (1·2–9·7)
CPK at inclusion (mg/dl) 1222 ± 668
Leucocyte count (cells/mm3) 5402 ± 2330
Lymphocyte count (cels/mm3) 1467 ± 220
Treated/naive to treatment 23/7
Treatment strategies
Glucocorticoids (%) 75
Other immunosuppressive drugs (AZA, MTX, HCLQ) (%) 90
Open in a new tab

AZA = azathioprine; CPK = creatine phosphokinase; DM = dermatomyositis; HCLQ = hydroxychloroquine; MTX = methotrexate; PM = polymiositis; s.d. = standard deviation.

IIM patients show increased numbers of proinflammatory T cells and decreased regulatory T cells

We found increased absolute numbers of Th17 cells (30·25 ± 6·49 versus 13·46 ± 2·95, P = 0·031) in PBMC from IIM patients in comparison to healthy controls, as well as a higher percentage of this T cell subset (2·14 ± 0·41 versus 0·62 ± 0·15, P = 0·004) (see Fig. 1). It is noteworthy that decreased absolute numbers (5·98 ± 1·61 versus 30·82 ± 8·38, P = 0·009) as well as percentages (0·41 ± 0·08 versus 1·43 ± 0·39, P = 0·021) of CD4+ regulatory T cells were also found. As CD8+ Tregs have been shown to play a role, particularly in muscle tissue infiltration 19, we also assessed this subset, which was decreased significantly in terms of absolute numbers in patients with IIM (6·80 ± 2·09 versus 19·80 ± 4·31, P = 0·015), as displayed in Fig. 2.

Fig 1.

Fig 1

Open in a new tab

T helper type 17 (Th17) cells are expanded in peripheral blood from idiopathic inflammatory myopathies (IIM) patients. Peripheral blood mononuclear cells (PBMCs) from IIM patients and healthy controls were isolated and stained for CD4 and interleukin (IL)-17A. Afterwards, cells were stimulated with plate bound anti-CD3 plus anti-CD28 for 1 h and treated with the transport inhibitor monesin, and CD4+/IL-17A+ cells were quantified by flow cytometry. We observed (a) increased percentage of peripheral Th17 cells in IIM patients compared to healthy controls. A representative zebra-plot from one patient with IIM and one healthy control is shown. (b) Bars represent the pooled data (mean ± standard deviation) from absolute cell numbers from 30 IIM patients and 30 age- and sex-matched healthy volunteers. *P < 0·05.

Fig 2.

Fig 2

Open in a new tab

Idiopathic inflammatory myopathies (IIM) patients show decreased peripheral regulatory T cells (Tregs). Multi-parametric flow cytometry was performed on peripheral blood mononuclear cells (PBMCs) from IIM patients and healthy controls. CD4+ and CD8+Tregs were assessed as follows: CD4Tregs [CD4+, CD25high, forkhead box protein 3 (FoxP3+)], CD8Tregs (CD8+, CD25high, FoxP3+). (a) Decreased percentages of peripheral CD4+ and CD8+ Tregs were found in IIM patients in comparison to healthy controls. A representative zebra-plot from one patient with IIM and one healthy control is shown. (b) Bars represent the pooled data (mean ± standard deviation) from absolute cell numbers from 30 IIM patients and 30 age- and sex-matched healthy volunteers. *P < 0·05.

Hence, peripheral T cells from patients with IIM are characterized by a highly proinflammatory T cell subset, such as Th17 cells, and display deficient numbers of suppressive regulatory CD4+ and CD8+ Tregs.

No differences were found between disease subtype, activity or use of immunosuppressive treatment.

Follicular helper T cells are globally expanded in IIM: Tfh2 and Tfh17 phenotypes are highly represented

Total follicular helper T cells measured as absolute numbers (28 ± 8·16 versus 6·64 ± 1·29, P = 0·031) or percentages (1·74 ± 0·31 versus 0·27 ± 0·04, P = 0·001) were increased in IIM patients when compared to healthy controls (Fig. 3). Three different phenotypes have been validated previously 15 for Tfh in terms of phenotypical markers (Tfh1, Tfh2 and Tfh17), as well as effector functions. As their potential role has been suggested in a previous study in juvenile dermatomyositis, we decided to assess these subsets.

Fig 3.

Fig 3

Open in a new tab

Follicular helper T cell expansion characterizes idiopathic inflammatory myopathies (IIM) patients. Follicular helper T cell subsets were assessed by multi-parametric flow cytometry from peripheral blood of IIM patients and healthy controls. Briefly, the gating strategy was as follows: follicular helper T cells (Tfh): we plotted a gate that included CD4+CXCR5+ cells, and from this gate we plotted three different gates, based on the expression of CXCR3 and CCR6, as follows: (a) Tfh1: CXCR3+/CCR6−; (b) Tfh2: CXCR3−/CCR6−; (c) Tfh17: CXCR3−/CCR6+. A representative zebra-plot from one patient with IIM and one healthy control is depicted.

We found expansion of Tfh2 and Tfh17 subsets in IIM patients in comparison to healthy controls, evaluated as absolute numbers (Tfh2: 9·49 ± 2·19 versus 1·66 ± 0·46, P = 0·005; Tfh17: 9·48 ± 2·83 versus 1·18 ± 0·21, P = 0·014) (Fig. 4) and percentages (Tfh2: 37·69 ± 2·44 versus 23·73 ± 2·97, P = 0·001; and Tfh17: 32·65 ± 1·79 versus 18·8 ± 1·04, P < 0·001), respectively (See Fig. 3). We found decreased percentages of Tfh1 cells in IIM patients in comparison to healthy controls (Tfh1: 20·06 ± 1·39 versus 34·46 ± 2·23, P < 0·001). Furthermore, no differences were found in terms of absolute numbers in this subset (Tfh1: 5·83 ± 1·96 versus 2·45 ± 1·56, P = 0·142). We were not able to find significant differences between disease subtype, activity or use of immunosuppressive treatment.

Fig 4.

Fig 4

Open in a new tab

Follicular helper T cell expansion is skewed towards follicular helper 2 T cells (Tfh2) and Tfh17 phenotypes. Follicular helper T cell subsets were assessed by multi-parametric flow cytometry from peripheral blood of idiopathic inflammatory myopathies (IIM) patients and healthy controls. Tfh subsets were defined as follows: we found increased absolute numbers of Tfh2 and Tfh17 subsets in IIM patients in comparison to healthy controls. Briefly, the gating strategy was as follows: (a) Tfh1: CXCR3+/CCR6−; (b) Tfh2: CXCR3−/CCR6−; (c) Tfh17: CXCR3−/CCR6+. Bars represent the pooled data (mean ± standard deviation) from absolute cell numbers from 30 IIM patients and 30 age- and sex-matched healthy volunteers. *P < 0·05.

Pro-apoptotic T cells are increased in peripheral blood from patients with IIM

CD28null T cells have been widely recognized as a T cell subset characterized by its pro-apoptotic ability 20 and its role in myotoxicity 13. Hence, we hypothesized that the frequency of this subset might be altered in the peripheral blood of IIM patients. According to our hypothesis, we found an impressive enhancement in absolute numbers (162·88 ± 32·29 versus 64 ± 17·35, P = 0·015) and percentages (11·38 ± 1·25 versus 2·81 ± 0·65, P = 0·001) of CD28null T cells in IIM in comparison to healthy controls (Fig. 5).

Fig 5.

Fig 5

Open in a new tab

Peripheral blood CD28null T cells are expanded in patients with idiopathic inflammatory myopathies (IIM). CD4+CD28null T cells were assessed by multi-parametric flow cytometry as follows: CD4+, CD28−, CD244+. (a) Increased percentages of peripheral CD4+CD28null cells were found in IIM patients in comparison to healthy controls. (a) A representative zebra-plot from one patient with IIM and one healthy control is shown. (b) Bars represent the pooled data (mean ± standard deviation) from absolute cell numbers from 30 IIM patients and 30 age- and sex-matched healthy volunteers. *P < 0·05.

Discussion

Multiple abnormalities in T cell subsets that infiltrate muscle in patients with IIM and some murine models have been reported 21,22. However, the profile in peripheral blood has not been addressed fully. Our data suggest that IIM patients are characterized by the presence of lymphopenia, an expansion of peripheral proinflammatory T cells, such as Tfh and Th17, as well as pro-apoptotic CD28null cells and a deficiency of suppressor populations of regulatory T cells (CD4+ and CD8+).

In the present study, we found a high frequency of lymphopenia in IIM, which is in agreement with previous reports. In one retrospective study, Viguier et al. 23 found that dermatomyositis patients showed lower peripheral lymphocyte count compared to healthy donors. Moreover, lymphopenia correlated with disease activity and was reversed upon glucocorticoid treatment. Our data suggest that IIM patients with lymphopenia were characterized by a deficiency in Tregs as well as increased numbers of Th17 cells. Lymphopenia has been associated with diverse abnormalities in T cell subsets in autoimmune diseases, such as SLE. In particular, lymphopenia related to disease activity has been associated with increased numbers of activated CD4+ T cells, as well as Th17 cells and decreased numbers of CD4+ Tregs, which is in agreement with our findings 24. In this context, lymphopenia has been related to specific autoantibodies and suppressive cell turnover in bone marrow, among others 25. However, these mechanisms have not been explored in IIM.

Th17 cells are one of the main players in the orchestration of a proinflammatory microenvironment in muscle tissue 22. IL-17 has been detected in the inflamed muscle tissue in IIM patients in comparison to healthy muscle 10. IL-17 has been shown to induce the production of IL-6 and CCL20 26 and is able to regulate survival and differentiation of antibody-producing B lymphocytes. Moreover, IL-17 is able to activate the integrin-linked/RhoGTPase pathway, which drives inflammatory migration and invasion by regulating cytoskeletal rearrangement 27. Accordingly, in myoblasts, IL-17 induced the expression of human leucocyte antigen (HLA) class I, c-fos, c-jun and nuclear factor kappa B (NF-κB), which further corroborates the proinflammatory role of Th17 cells in IIM. Moreover, IL-17 induced activation of NF-κB inhibits myocyte migration and differentiation, mainly by inducing the expression of TNF-like weak inducer of apoptosis (TWEAK), which highlights the role of Th17 cells in impairing muscle regeneration and repair 28. IL-23, IL-17 and IL-12 mRNA are also over-expressed in muscle tissue from IIM patients 9, which suggest activation of the IL-17/IL-23 pathway. Hence, IL-17 plays a pivotal role in the inflammatory environment in inflamed muscle tissue, as well as on the induction of autoantibodies and impairment of muscle regeneration, which could further enhance the autoimmune pathogenic response. Our work is in agreement with previous data regarding increased frequency of Th17 cells in PM and DM PBMCs 29,30. However, it is still a matter of controversy regarding whether Th17 cell differentiation takes place before the migration to muscle or if it develops in situ.

The balance between proinflammatory T cell subsets and regulatory T cells has been shown to be a key element in the maintenance of peripheral tolerance. In the present work we found increased Th17 numbers and decreased Treg numbers (CD4 and CD8). Our findings regarding lower Treg numbers in peripheral blood from IIM patients are in agreement with previous data, such as the work by Antiga et al. 21 and Banica et al. 31. Even though we did not address the suppressor activity of this subset, it has been shown previously that Tregs inhibit the lytic capacity of cytotoxic cells towards myoblasts 12. Moreover, in an autoimmune myositis murine model, depletion of Tregs was related to increased disease activity as well as higher production of anti-synthetase antibodies, and transfer of expanded Tregs correlated with decreased inflamed muscle tissue 32, highlighting the role of Tregs in IIM pathogenesis. It is feasible that decreased Tregs numbers are accompanied by lower suppressor activity and a more permissive environment for cytotoxicity.

It has been argued that FoxP3+ T cells could represent a dormant reservoir with the potential to become regulatory cells after homeostatic expansion 33. The lower numbers of CD4 and CD8 Tregs in myositis patients could be related to increased recruitment of this subset to the affected muscle, which could be enhanced by the induction of chemokines by Th17 cells. Hence, our results suggest that the imbalance between peripheral proinflammatory T cells and Tregs might play a role in the maintenance of IIM.

CXCR5+CD4+ T cells are considered to be the circulating memory compartment of Tfh. Moreover, distinct phenotypes have been acknowledged for this subset, such as Tfh1, Tfh2 and Tfh17 15. The expansion of circulating Tfh cells has been implicated in the breach of peripheral tolerance and the development and maintenance of autoimmune diseases, such as SLE 34. Data regarding this T cell subset in IIM are quite scant; the only previous work is that published by Morita et al. 15, in which they found expansion of Tfh2 and Tfh17 cells in juvenile dermatomyositis patients. The expansion of total Tfh cells as well as the skewing towards Tfh2 and Tfh17 phenotypes were related to disease activity assessed by the presence of skin rash and muscular weakness. We were not able to find any differences between active and inactive patients; however, we had a more heterogeneous group (DM and PM), a more detailed tool for disease activity assessment was used and our sample size was lower, which could account for the different findings. Regarding immunosuppressive treatment [corticosteroids, methotrexate, azathioprine, hydroxychloroquine (HCLQ)], we were not able to find any differences, which is in agreement to that reported by Morita et al. 15. Previous work on Tfh expansion on SLE has also shown no relationship to immunosuppressive treatment 34. To our knowledge, the present work is the first addressing Tfh cells in adult IIM patients. In agreement with the aforementioned work, we found expansion of Tfh2 and Tfh17 cells in all IIM study groups. Tfh2 and Tfh17 are associated with increased numbers of circulating plasmablasts and induce naive B cells to produce immunoglobulins through IL-21. Moreover, they differentially induced isotype-switching, Tfh2 promotes immunoglobulin (Ig)G and IgE secretion and Tfh17 was related to IgG and IgA production 14,15,35. Hence, the skewing towards Tfh2 and Tfh17 cells seems to play a role in the abnormal humoral responses in IIM patients.

In order to fully address potential pathogenic T cell subsets, we also evaluated CD28null cells. In agreement with previous studies, we found an increased percentage of CD28null cells in PBMCs from patients with IIM. Fasth et al. 13 showed that CD28null cells from IIM patients produce high amounts of proinflammatory cytokines, such as TNF and IFN-γ as well as perforin. Also, CD28null cells are able to promote Fas-mediated apoptosis of myocytes, dependent upon the expression of caspases 3 and 8 9. These cells are able to induce myotoxicity and are present in muscle infiltrates from IIM samples. As well as myositis, this cell subset has been shown to be expanded in other autoimmune diseases and during ageing 36,37. None the less, the molecular mechanisms related to the expansion of this subset have not been addressed fully. However, it has been suggested that these cells are related to NK lineage and are induced by increasing levels of IFN-α 38, which has also been related to telomere erosion 39. History of viral infections has also been related to expansion of CD28null cells, particularly cytomegalovirus (CMV) 40. The expansion of this highly inflammatory, cytotoxic and pro-apoptotic T cell subset might play a key role in the induction and maintenance of autoimmune myositis.

In summary, IIM patients are characterized by expansion of peripheral proinflammatory T cells, such as Tfh and Th17, as well as pro-apoptotic CD28null cells and a deficiency of suppressor populations of Tregs (CD4+ and CD8+), which might be related to the physiopathogenic scheme of the disease.

Acknowledgments

This work was supported by a grant from CONACYT (166033, to D. G. M.).

Author contributions

All authors were involved in drafting the paper or revising it critically for important intellectual content, and all authors approved the final version. J. A.-V. had full access to the data and takes responsibility for the integrity of the data. For study conception and design: D. G.-M., F. E.-O. and J. A.-V.; for acquisition of the data: D. G.-M., E. E.-O., K. S.-de A., J. R.-T. and P. V.-O.; and for analysis and interpretation of the data: D. G.-M., F. E-O., K. S-de A., J. R.-T., P. V.-O. and J. A.-V.

Disclosure

The authors declare they have no competing financial interests.

References

  1. Brandao M, Marinho A. Idiopathic inflammatory myopathies: definition and management of refractory disease. Autoimmun Rev. 2011;10:720–724. doi: 10.1016/j.autrev.2011.05.021. [DOI] [PubMed] [Google Scholar]
  2. Furst DE, Amato AA, Iorga SR, Gajria K, Fernandes AW. Epidemiology of adult idiopathic inflammatory myopathies in a U.S. managed care plan. Muscle Nerve. 2012;45:676–683. doi: 10.1002/mus.23302. [DOI] [PubMed] [Google Scholar]
  3. Fernandez C, Bardin N, De Paula AM, et al. Correlation of clinicoserologic and pathologic classifications of inflammatory myopathies: study of 178 cases and guidelines for diagnosis. Medicine (Balt) 2013;92:15–24. doi: 10.1097/MD.0b013e31827ebba1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Linklater H, Pipitone N, Rose MR, et al. Classifying idiopathic inflammatory myopathies: comparing the performance of six existing criteria. Clin Exp Rheumatol. 2013;31:767–769. [PubMed] [Google Scholar]
  5. Venalis P, Lundberg IE. Immune mechanisms in polymyositis and dermatomyositis and potential targets for therapy. Rheumatology. 2014;53:397–405. doi: 10.1093/rheumatology/ket279. [DOI] [PubMed] [Google Scholar]
  6. Walsh RJ, Kong SW, Yao Y, et al. Type I interferon-inducible gene expression in blood is present and reflects disease activity in dermatomyositis and polymyositis. Arthritis Rheum. 2007;56:3784–3792. doi: 10.1002/art.22928. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Selva-O'Callaghan A, Labrador-Horrillo M, Solans-Laque R, Simeon-Aznar CP, Martinez-Gomez X, Vilardell-Tarres M. Myositis-specific and myositis-associated antibodies in a series of eighty-eight Mediterranean patients with idiopathic inflammatory myopathy. Arthritis Rheum. 2006;55:791–798. doi: 10.1002/art.22237. [DOI] [PubMed] [Google Scholar]
  8. Greenberg SA, Bradshaw EM, Pinkus JL, et al. Plasma cells in muscle in inclusion body myositis and polymyositis. Neurology. 2005;65:1782–1787. doi: 10.1212/01.wnl.0000187124.92826.20. [DOI] [PubMed] [Google Scholar]
  9. Kondo M, Murakawa Y, Harashima N, Kobayashi S, Yamaguchi S, Harada M. Roles of proinflammatory cytokines and the Fas/Fas ligand interaction in the pathogenesis of inflammatory myopathies. Immunology. 2009;128:e589–599. doi: 10.1111/j.1365-2567.2008.03039.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Chevrel G, Page G, Granet C, Streichenberger N, Varennes A, Miossec P. Interleukin-17 increases the effects of IL-1 beta on muscle cells: arguments for the role of T cells in the pathogenesis of myositis. J Neuroimmunol. 2003;137:125–133. doi: 10.1016/s0165-5728(03)00032-8. [DOI] [PubMed] [Google Scholar]
  11. Wing K, Sakaguchi S. Regulatory T cells exert checks and balances on self tolerance and autoimmunity. Nat Immunol. 2010;11:7–13. doi: 10.1038/ni.1818. [DOI] [PubMed] [Google Scholar]
  12. Waschbisch A, Schwab N, Ruck T, Stenner MP, Wiendl H. FOXP3+ T regulatory cells in idiopathic inflammatory myopathies. J Neuroimmunol. 2010;225:137–142. doi: 10.1016/j.jneuroim.2010.03.013. [DOI] [PubMed] [Google Scholar]
  13. Fasth AE, Dastmalchi M, Rahbar A, et al. T cell infiltrates in the muscles of patients with dermatomyositis and polymyositis are dominated by CD28null T cells. J Immunol. 2009;183:4792–4799. doi: 10.4049/jimmunol.0803688. [DOI] [PubMed] [Google Scholar]
  14. Linterman MA, Rigby RJ, Wong RK, et al. Follicular helper T cells are required for systemic autoimmunity. J Exp Med. 2009;206:561–576. doi: 10.1084/jem.20081886. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Morita R, Schmitt N, Bentebibel SE, et al. Human blood CXCR5(+)CD4(+) T cells are counterparts of T follicular cells and contain specific subsets that differentially support antibody secretion. Immunity. 2011;34:108–121. doi: 10.1016/j.immuni.2010.12.012. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Bohan A, Peter JB. Polymyositis and dermatomyositis (first of two parts) N Engl J Med. 1975;292:344–347. doi: 10.1056/NEJM197502132920706. [DOI] [PubMed] [Google Scholar]
  17. Hoogendijk JE, Amato AA, Lecky BR, et al. 119th ENMC international workshop: trial design in adult idiopathic inflammatory myopathies, with the exception of inclusion body myositis, 10–12 October 2003, Naarden, The Netherlands. Neuromuscul Disord. 2004;14:337–345. doi: 10.1016/j.nmd.2004.02.006. [DOI] [PubMed] [Google Scholar]
  18. Isenberg DA, Allen E, Farewell V, et al. International consensus outcome measures for patients with idiopathic inflammatory myopathies. Development and initial validation of myositis activity and damage indices in patients with adult onset disease. Rheumatology. 2004;43:49–54. doi: 10.1093/rheumatology/keg427. [DOI] [PubMed] [Google Scholar]
  19. Okiyama N, Sugihara T, Oida T, et al. T lymphocytes and muscle condition act like seeds and soil in a murine polymyositis model. Arthritis Rheum. 2012;64:3741–3749. doi: 10.1002/art.34629. [DOI] [PubMed] [Google Scholar]
  20. Posnett DN, Edinger JW, Manavalan JS, Irwin C, Marodon G. Differentiation of human CD8 T cells: implications for in vivo persistence of CD8+ CD28− cytotoxic effector clones. Int Immunol. 1999;11:229–241. doi: 10.1093/intimm/11.2.229. [DOI] [PubMed] [Google Scholar]
  21. Antiga E, Kretz CC, Klembt R, et al. Characterization of regulatory T cells in patients with dermatomyositis. J Autoimmun. 2010;35:342–350. doi: 10.1016/j.jaut.2010.07.006. [DOI] [PubMed] [Google Scholar]
  22. Chevrel G, Page G, Miossec P. Novel aspects on the contribution of T cells and dendritic cells in the pathogenesis of myositis. Autoimmunity. 2006;39:171–176. doi: 10.1080/08916930600622173. [DOI] [PubMed] [Google Scholar]
  23. Viguier M, Fouere S, de la Salmoniere P, et al. Peripheral blood lymphocyte subset counts in patients with dermatomyositis: clinical correlations and changes following therapy. Medicine (Balt) 2003;82:82–86. doi: 10.1097/00005792-200303000-00002. [DOI] [PubMed] [Google Scholar]
  24. Gomez-Martin D, Diaz-Zamudio M, Vanoye G, Crispin JC, Alcocer-Varela J. Quantitative and functional profiles of CD4+ lymphocyte subsets in systemic lupus erythematosus patients with lymphopenia. Clin Exp Immunol. 2011;164:17–25. doi: 10.1111/j.1365-2249.2010.04309.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Amasaki Y, Kobayashi S, Takeda T, et al. Up-regulated expression of Fas antigen (CD95) by peripheral naive and memory T cell subsets in patients with systemic lupus erythematosus (SLE): a possible mechanism for lymphopenia. Clin Exp Immunol. 1995;99:245–250. doi: 10.1111/j.1365-2249.1995.tb05540.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Tournadre A, Lenief V, Miossec P. Expression of Toll-like receptor 3 and Toll-like receptor 7 in muscle is characteristic of inflammatory myopathy and is differentially regulated by Th1 and Th17 cytokines. Arthritis Rheum. 2010;62:2144–2151. doi: 10.1002/art.27465. [DOI] [PubMed] [Google Scholar]
  27. Moran EM, Mastaglia FL. The role of interleukin-17 in immune-mediated inflammatory myopathies and possible therapeutic implications. Neuromuscul Disord. 2014 doi: 10.1016/j.nmd.2014.06.432. Jun 20. pii: S0960-8966(14)00583-5. doi: 10.1016/j.nmd.2014.06.432. [Epub ahead of print] [DOI] [PubMed] [Google Scholar]
  28. Moran EM, Mastaglia FL. Cytokines in immune-mediated inflammatory myopathies: cellular sources, multiple actions and therapeutic implications. Clin Exp Immunol. 2014;178:405–415. doi: 10.1111/cei.12445. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Tang X, Tian X, Zhang Y, et al. Correlation between the frequency of Th17 cell and the expression of microRNA-206 in patients with dermatomyositis. Clin Dev Immunol. 2013;2013:1–7. doi: 10.1155/2013/345347. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Tournadre A, Porcherot M, Cherin P, Marie I, Hachulla E, Miossec P. Th1 and Th17 balance in inflammatory myopathies: interaction with dendritic cells and possible link with response to high-dose immunoglobulins. Cytokine. 2009;46:297–301. doi: 10.1016/j.cyto.2009.02.013. [DOI] [PubMed] [Google Scholar]
  31. Banica L, Besliu A, Pistol G, et al. Quantification and molecular characterization of regulatory T cells in connective tissue diseases. Autoimmunity. 2009;42:41–49. doi: 10.1080/08916930802282651. [DOI] [PubMed] [Google Scholar]
  32. Allenbach Y, Solly S, Gregoire S, et al. Role of regulatory T cells in a new mouse model of experimental autoimmune myositis. Am J Pathol. 2009;174:989–998. doi: 10.2353/ajpath.2009.080422. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Zelenay S, Lopes-Carvalho T, Caramalho I, Moraes-Fontes MF, Rebelo M, Demengeot J. Foxp3+ CD25− CD4 T cells constitute a reservoir of committed regulatory cells that regain CD25 expression upon homeostatic expansion. Proc Natl Acad Sci USA. 2005;102:4091–4096. doi: 10.1073/pnas.0408679102. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Simpson N, Gatenby PA, Wilson A, et al. Expansion of circulating T cells resembling follicular helper T cells is a fixed phenotype that identifies a subset of severe systemic lupus erythematosus. Arthritis Rheum. 2010;62:234–244. doi: 10.1002/art.25032. [DOI] [PubMed] [Google Scholar]
  35. King IL, Mohrs M. IL-4-producing CD4+ T cells in reactive lymph nodes during helminth infection are T follicular helper cells. J Exp Med. 2009;206:1001–1007. doi: 10.1084/jem.20090313. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Fasth AE, Snir O, Johansson AA, et al. Skewed distribution of proinflammatory CD4+CD28null T cells in rheumatoid arthritis. Arthritis Res Ther. 2007;9:R87. doi: 10.1186/ar2286. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Markovic-Plese S, Cortese I, Wandinger KP, McFarland HF, Martin R. CD4+CD28− costimulation-independent T cells in multiple sclerosis. J Clin Invest. 2001;108:1185–1194. doi: 10.1172/JCI12516. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Eloranta ML, Barbasso Helmers S, Ulfgren AK, Ronnblom L, Alm GV, Lundberg IE. A possible mechanism for endogenous activation of the type I interferon system in myositis patients with anti-Jo-1 or anti-Ro 52/anti-Ro 60 autoantibodies. Arthritis Rheum. 2007;56:3112–3124. doi: 10.1002/art.22860. [DOI] [PubMed] [Google Scholar]
  39. Reed JR, Vukmanovic-Stejic M, Fletcher JM, et al. Telomere erosion in memory T cells induced by telomerase inhibition at the site of antigenic challenge in vivo. J Exp Med. 2004;199:1433–1443. doi: 10.1084/jem.20040178. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Appay V, Dunbar PR, Callan M, et al. Memory CD8+ T cells vary in differentiation phenotype in different persistent virus infections. Nat Med. 2002;8:379–385. doi: 10.1038/nm0402-379. [DOI] [PubMed] [Google Scholar]

Articles from Clinical and Experimental Immunology are provided here courtesy of British Society for Immunology

RESOURCES