T cell receptor clonotypes in skin lesions from patients with systemic lupus erythematosus

Immune repertoire: Revealing the "real-time" adaptive immune response in autoimmune diseases

The diversity of the immune repertoire (IR) enables the human immune system to distinguish multifarious antigens (Ags) that humans may encounter throughout life. At the same time, bias or abnormalities in the IR also pay a contribution to the pathogenesis of autoimmune diseases. Rapid advancements in high-throughput sequencing (HTS) technology have ushered in a new era of immune studies, revealing novel molecules and pathways that might result in autoimmunity. In the field of IR, HTS can monitor the immune response status and identify disease-specific immune repertoires. In this review, we summarize updated progress on the mechanisms of the IR and current related studies on four autoimmune diseases, particularly focusing on systemic lupus erythematosus (SLE). These autoimmune diseases can exhibit slightly or significantly skewed IRs and provide novel insights that inform our comprehending of disease pathogenesis and provide potential targets for diagnosis and treatment.

CD28 null CD4 T-cell expansions in autoimmune disease suggest a link with cytomegalovirus infection

Immunosenescence is thought to contribute to the increase of autoimmune diseases in older people. Immunosenescence is often associated with the presence of an expanded population of CD4 T cells lacking expression of CD28 (CD28 ^null). These highly cytotoxic CD4 T cells were isolated from disease-affected tissues in patients with rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, or other chronic inflammatory diseases and their numbers appeared to be linked to disease severity. However, we recently demonstrated that the common herpes virus, cytomegalovirus (CMV), not ageing, is the major driver of this subset of cytotoxic T cells. In this review, we discuss how CMV might potentiate and exacerbate autoimmune disease through the expansion of CD28 ^null CD4 T cells.

Case report for recurrent and new-onset SLE patients treated by high-dose glucocorticoid therapy: Characteristics of peripheral TCR beta chain CDR3 repertoires

RATIONALE

High-dose glucocorticoid therapy has been widely applied in clinical practice in systemic lupus erythematosus (SLE)patients, but less is known about the changes of T cells, especially the T cell receptor (TCR) repertoires, during the treatment. The aim of this paper is to describe the changes of TCR that recurrent and new-onset SLE patients treated by high-dose glucocorticoid therapy.

PATIENT CONCERNS

Drugs of clinical treatment of SLE mainly include glucocorticoid, immunosuppressive agents, nonsteroidal anti-inflammatory drugs and B cell targeted drugs, etc, but the clinical symptoms were in remission and recurrent of onset patients with SLE.

DIAGNOSES

Refer to the diagnostic criteria for SLE in 2011 by the American society of rheumatology.

INTERVENTIONS

All patients were treated with High-dose glucocorticoid therapy and surveyed the TCR repertoires at 3 monitoring moments (before treatment, one month after treatment, and 3 months after treatment) to analyze the relationship between the characteristics of TCR repertoire and the highdose glucocorticoid therapy.

OUTCOMES

We found that high-dose glucocorticoid therapy resulted in clinical symptom remission, as well as change of diversity, highly expanded clones (HEC), usage of TCR beta chain variable gene (TRBV)/TCR beta chain joining gene (TRBJ), and overlapped sequences of TCR beta chain complementarity determining region 3 (CDR3) repertoires. This suggests that the effect of high-dose glucocorticoids on TCR repertoires is closely related to individual autoimmune T cells.

LESSONS

In this study, we have shown that we could evaluate the effect of therapy, the pathogenesis, and the prognosis for the patients with SLE by monitoring the TCR CDR3 repertoires. It could afford a new method to find the therapeutic target of SLE.

Chronic graft-versus-host-disease in CD34(+)-humanized NSG mice is associated with human susceptibility HLA haplotypes for autoimmune disease

Chronic graft-versus-host disease (cGVHD) is a significant hurdle to long-term hematopoietic stem-cell transplantation success. Insights into the pathogenesis and mechanistical investigations of novel therapeutic strategies are limited as appropriate animal models are missing. The immunodeficient NSG mouse - when humanized with human bone marrow, fetal liver and thymus (BLT NSG) - is prone for cGVHD, yet mainly affects the skin. In contrast, the NSG mouse humanized exclusively with CD34(+)-selected, CD3(+)-depleted stem cells (CD34(+)NSG) has neither been described for acute nor chronic GVHD so far. This is the first report about the development of systemic autoimmune cGVHD ≥24 weeks post stem cell receipt involving lung, liver, skin, gingiva and intestine in two NSG cohorts humanized with CD34(+) grafts from different donors. Affected mice presented with sclerodermatous skin, fibrotic lung, severe hepatitis, and massive dental malformation/loss. CD4(+)-dominated, TH2-biased, bulky T-cell infiltrates featured highly skewed T cell receptor (TCR) repertoires, clonal expansions, and autoreactive TCRs. In affected tissues profibrotic IL-13 and -4 dominated over TH1 cytokines IFN-γ and TNF-α. Thus, the time point of manifestation and the phenotype match human systemic pleiotropic sclerodermatous GVHD. The CD34(+)NSG-model's intrinsic deficiency of thymus, thymus-derived regulatory T cells (nTreg) and B cells emphasizes the role of the genetic polymorphism and the cytokines in the pathogenesis of cGVHD. Importantly, the only factor discriminating diseased versus non-diseased CD34(+)NSG cohorts were two risk HLA haplotypes that in human mediate susceptibility for autoimmune disease (psoriasis). Thus, the CD34(+)NSG model may serve as a platform for addressing issues related to the pathophysiology and treatment of human autoimmunity and chronic GVHD.

Longitudinal analysis of peripheral blood T cell receptor diversity in patients with systemic lupus erythematosus by next-generation sequencing

INTRODUCTION

T cells play an important role in the pathogenesis of systemic lupus erythematosus (SLE). Clonal expansion of T cells correlating with disease activity has been observed in peripheral blood (PB) of SLE subjects. Recently, next-generation sequencing (NGS) of the T cell receptor (TCR) β loci has emerged as a sensitive way to measure the T cell repertoire. In this study, we utilized NGS to assess whether changes in T cell repertoire diversity in PB of SLE patients correlate with or predict changes in disease activity.

METHODS

Total RNA was isolated from the PB of 11 SLE patients. Each subject had three samples, collected at periods of clinical quiescence and at a flare. Twelve age-matched healthy controls (HC) were used for reference. NGS was used to profile the complementarity-determining region 3 (CDR3) of the rearranged TCR β loci.

RESULTS

Relative to the HC, SLE patients (at quiescence) demonstrated a 2.2-fold reduction in repertoire diversity in a given PB volume (P <0.0002), a more uneven distribution of the repertoire (Gini coefficient, HC vs SLE, P = 0.015), and a trend toward increased percentage of expanded clones in the repertoire (clone size >1.0%, HC vs SLE, P = 0.078). No significant correlation between the overall repertoire diversity and clinical disease activity was observed for most SLE patients with only two of eleven SLE patients showing a decreasing trend in repertoire diversity approaching the flare time point. We did not observe any overlap of CDR3 amino acid sequences or a preferential Vβ or Jβ gene usage among the top 100 expanded clones from all SLE patients. In both HC and SLE, the majority of the expanded clones were remarkably stable over time (HC = 5.5 ±0.5 months, SLE = 7.2 ±2.4 months).

CONCLUSIONS

A significant decrease in T cell repertoire diversity was observed in PB of SLE patients compared to HC. However, in most SLE patients, repertoire diversity did not change significantly with increases in disease activity to a flare. Thus, without a priori knowledge of disease-specific clones, monitoring TCR repertoire in PB from SLE patients is not likely to be useful to predict changes in disease activity.

Analysis of the interindividual conservation of T cell receptor alpha- and beta-chain variable regions gene in the peripheral blood of patients with systemic lupus erythematosus

The aim of this study was to find conserved motifs in specific T cell receptor (TCR) alpha- and beta-chains, and to analyse the association between complementarity determining region 3 (CDR3) spectratype and systemic lupus erythematosus (SLE) activity. TCR alpha-and beta-chain CDR3 spectratypes were analysed in 20 SLE patients. The CDR3 spectratypes of three patients were monitored over time, and the CDR3 regions of clonally expanded T cells were sequenced. CDR3 spectratype analysis showed prominent usage of TCR AV8, AV14, AV23, AV30, AV31, BV2, BV8, BV11, BV14, BV16, BV19 and BV24 families in SLE patients. The CDR3 spectratype showed dynamic change correlating with SLE activity. The sequence of the CDR3 region in clonally expanded T cells suggested a conserved GGX amino acid motif in both alpha- and beta-chains. The Ja34 and Jb2s1 region genes were found in high frequency. Both TCR Valpha and Vbeta gene usage is highly restricted in SLE, suggesting that the TCRs recognize a limited number of antigenic epitopes. The conserved motifs and limited use of joining region genes may indicate the recognition of similar antigenic epitopes in multiple individuals.

Photosensitivity in rheumatic diseases

There have been a number of recent advances in the genetic understanding of photosensitive rheumatic diseases, especially subacute cutaneous lupus erythematosus and dermatomyositis. These advances support the concept that increased numbers of ultraviolet light-induced apoptotic cells in skin lead to a supra-threshold concentration of antigenic peptides. The current genetic data suggest that increased keratinocyte apopotosis can result from increased amounts of TNF-alpha that induce apoptosis due to a ultraviolet light-sensitive TNF promoter polymorphism or to decreased clearance of apototic cells due to polymorphisms associated with decreased serum levels of collectins such as C1q and mannose-binding lectin. These diseases are frequently oligogenic, and other yet to be elucidated genes will, in individual patients, lead to increased numbers of apoptotic cells associated with these cutaneous autoimmune diseases. In the presence of specific MHC class I and II genes, antigen-presenting cells initiate a primary immune response that leads to cutaneous, and likely systemic, autoimmune disease.

Liposomal ursolic acid (merotaine) increases ceramides and collagen in human skin

Skin wrinkling and xerosis associated with aging result from decreases of dermal collagen and stratum corneum ceramide content. This study demonstrates that ursolic acid incorporated into liposomes (Merotaine) increases both the ceramide content of cultured normal human epidermal keratinocytes and the collagen content of cultured normal human dermal fibroblasts. In clinical tests, Merotaine increased the ceramide content in human skin over an 11-day period. Merotaine has effects on keratinocyte differentiation and dermal fibroblast collagen synthesis similar to retinoids. However, unlike retinoids, Merotaine increases ceramide content of human keratinocytes. Ursolic acid may bind to members of the glucocorticoid receptor family to initiate changes in keratinocyte gene transcription.

Selection of conserved TCR VDJ rearrangements in chronic psoriatic plaques indicates a common antigen in psoriasis vulgaris

Psoriasis vulgaris is a common HLA-associated inflammatory skin disease. Although its etiology is still unknown, it is thought to involve T cell-mediated inflammatory mechanisms. In examining the lesional psoriatic TCR beta chain (TCRB) usage in a pair of identical twins concordant for psoriasis, we observed repetitive TCR VDJ rearrangements which indicated antigen-specific oligoclonal T cell expansion. Several of these TCRB rearrangements were identical or highly homologous in the amino acid composition of the complementarity determining region 3 (CDR3), suggesting that T cells with these TCR might be important for disease manifestation. This conclusion was strengthened by TCR analysis of other psoriasis patients. Several repetitive lesional TCRB rearrangements were found that were similar to the conserved CDR3 seen in the twins. Since TCR antigen specificity is largely determined by the beta chain CDR3, selection of T cells with conserved TCRB CDR3 motifs could indicate the presence of a common antigen as a major target of the lesional psoriatic immune response.

T-cell mediated inflammatory pathway in osteoarthritis

Osteoarthritis (OA) is not caused by a simple consequence of aging and cartilage degradation. Based on the conventional paradigm, OA has been considered a degenerative joint disorder. However, the dominant clinical symptom has been characterized by a non-infectious chronic inflammatory condition with infiltration of inflammatory cells in the synovial tissue or synovial fluid, especially in the early stage of the disease. The inflammatory process appeared to develop degeneration of chondrocytes and/or formation of osteophytes. Immunohistochemical staining of synovial tissue with OA in the early stage, suggests the presence of T-cell infiltration in the perivascular area, some of which were CD4 positive T cells. Among the T cells, we identified the clonality of restricted TCR usage of Vbeta chain by single strand conformation polymorphism (SSCP) method on T-cell repertoire. Therefore we address the immune response in primary OA.