Clinical and Immunologic Profiles in Incomplete Lupus Erythematosus and Improvement with Hydroxychloroquine Treatment

Objective. The study goals were to evaluate performance of SLE classification criteria, to define patients with incomplete lupus erythematosus (ILE), and to probe for features in these patients that might be useful as indicators of disease status and hydroxychloroquine response. Methods. Patients with ILE (N=70) and SLE (N=32) defined by the 1997 American College of Rheumatology criteria were reclassified using the 2012 Systemic Lupus International Collaborating Clinics criteria. Disease activity, patient reported outcomes, and levels of Type I interferon- (IFN-) inducible genes, autoantibodies, and cytokines were measured. Subgroups treated with hydroxychloroquine (HCQ) were compared to patients not on this drug. Results. The classification sets were correlated (R2=0.87). ILE patients were older (P=0.0043) with lower disease activity scores (P<0.001) and greater dissatisfaction with health status (P=0.034) than SLE patients. ILE was associated with lower levels of macrophage-derived cytokines and levels of expressed Type I IFN-inducible genes. Treatment of ILE with HCQ was associated with better self-reported health status scores and lower expression levels of Type I IFN-inducible genes than ILE patients not on HCQ. Conclusion. The 2012 SLICC SLE classification criteria will be useful to define ILE in trials. Patients with ILE have better health status and immune profiles when treated with HCQ

Neutrophil and lymphocyte counts are associated with different immunopathological mechanisms in systemic lupus erythematosus

Objective: Neutrophils contribute to the SLE pathogenesis. Neutrophil to lymphocyte ratio (NLR) is reported to correlate with disease activity in SLE. The aim of the study was to evaluate whether NLR reflects underlying immunopathogenic activity in SLE, as well as to determine the contribution of each component of NLR, neutrophil and lymphocyte count. Methods: Data were obtained from a cohort of patients with SLE (n=141) recruited at Lund University, Sweden. NLR levels were compared between patients with SLE and healthy controls (n=79). The relationship between NLR and clinical and immunological markers was examined using Mann-Whitney U test and logistic regression analysis. High NLR was defined as above the 90th percentile of healthy individuals. Results: Patients with SLE had elevated neutrophil count (p=0.04) and reduced lymphocyte count (p<0.0001), resulting in elevated NLR as compared with healthy controls (p<0.0001). Patients with high NLR had more active disease, and were more frequently on prednisone use and immunosuppressive medicines. High NLR was associated with immune complex (IC)-driven disease with presence of antidouble-stranded DNA antibodies (p=0.006), circulating ICs (p=0.02) and type I interferon (IFN) activity (p=0.009). Further, high NLR was associated with neutrophil abnormalities, including enrichment for low-density granulocytes (LDGs) (p=0.001), and increased levels of the serum neutrophil activation marker, calprotectin (p=0.02). Assessing the individual components within NLR, that is, neutrophil and lymphocyte count, high neutrophil count was associated with neutrophil activation markers (p<0.0001), whereas low lymphocyte count was associated with type I IFN activity and elevated numbers of LDGs (p=0.006 and p=0.001, respectively). Conclusions: NLR is elevated in patients with SLE as compared with healthy individuals, and is associated with key immunopathological events, including type I IFN activity and neutrophil activation. Neutrophil and lymphocyte count reflected different aspects of the pathogenesis of SLE. Further studies are needed to determine the causality of the associations

CD70-expressing CD4 T cells produce IFN-γ and IL-17 in rheumatoid arthritis

OBJECTIVE: CD70-expressing CD4 T cells are enriched in RA and promote autoimmunity via co-stimulatory CD70-CD27 interaction. This study aimed to explore the phenotype and cytokine production of CD70(+) CD4 T cells in RA. METHODS: Peripheral blood mononuclear cells from 32 RA patients were isolated and frequencies of CD70(+) cells within different CD4 T subsets were analysed using flow cytometry. IFN-γ and IL-17 production were compared between the CD70(+) and CD70(-) cells. Expression of master transcription factors T-bet, GATA3 and retinoic acid-related orphan receptor gamma t (RORγt) were examined by real-time PCR. Results are presented as mean (s.e.m.). RESULTS: CD4 T cells of healthy controls rarely expressed CD70 as compared with CD4 T cells of RA patients [mean 0.9% (s.e.m. 0.3%) vs 7.6 (0.6), P < 0.001]. In RA, CD70(+) cells were present within all CD4 T cell subsets, i.e. CD45RA(+)CCR7(+) naive, CD45RA(-)CCR7(+) central memory, CD45RA(-)CCR7(-) effector memory and CD45RA(+)CCR7(-) terminally differentiated effector memory T cells with a mean frequency of 3.9% (s.e.m. 1.1%), 4.0 (0.5), 4.2 (0.7) and 9.4 (4.3), respectively. As compared to CD70(-) CD4 T cells, CD70(+) CD4 T cells produced significantly more IFN-γ and IL-17 after short activation. CD70(+) CD4 T cells preferentially expressed transcription factor RORγt. CONCLUSION: CD70(+) CD4 T cells are enriched in RA and may directly contribute to RA pathogenesis by producing IFN-γ and IL-17. Targeting CD70(+) CD4 T cells might offer new therapeutic opportunities in RA

SLE peripheral blood B cell, T cell and myeloid cell transcriptomes display unique profiles and each subset contributes to the interferon signature.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that is characterized by defective immune tolerance combined with immune cell hyperactivity resulting in the production of pathogenic autoantibodies. Previous gene expression studies employing whole blood or peripheral blood mononuclear cells (PBMC) have demonstrated that a majority of patients with active disease have increased expression of type I interferon (IFN) inducible transcripts known as the IFN signature. The goal of the current study was to assess the gene expression profiles of isolated leukocyte subsets obtained from SLE patients. Subsets including CD19(+) B lymphocytes, CD3(+)CD4(+) T lymphocytes and CD33(+) myeloid cells were simultaneously sorted from PBMC. The SLE transcriptomes were assessed for differentially expressed genes as compared to healthy controls. SLE CD33(+) myeloid cells exhibited the greatest number of differentially expressed genes at 208 transcripts, SLE B cells expressed 174 transcripts and SLE CD3(+)CD4(+) T cells expressed 92 transcripts. Only 4.4% (21) of the 474 total transcripts, many associated with the IFN signature, were shared by all three subsets. Transcriptional profiles translated into increased protein expression for CD38, CD63, CD107a and CD169. Moreover, these studies demonstrated that both SLE lymphoid and myeloid subsets expressed elevated transcripts for cytosolic RNA and DNA sensors and downstream effectors mediating IFN and cytokine production. Prolonged upregulation of nucleic acid sensing pathways could modulate immune effector functions and initiate or contribute to the systemic inflammation observed in SLE

Confirmation of Myeloid Array Results by CD169 Protein Expression

<p>. The high expression of CD169 (<i>SIGLEC1</i>) by myeloid cells in the arrays was confirmed by analysis of CD33⁺CD14⁺ myeloid cells in a second cohort. (A) CD14⁺ myeloid cells were gated for CD16^dim and CD16^bright myeloid cells. (B) Histograms of CD169 expression on classical (CD14⁺CD16^dim) and nonclassical (CD14⁺CD16⁺) myeloid cells. (C) Frequency of CD169⁺ cells in the classical (CD14⁺CD16^dim) myeloid subset comparing HC to SLE patients. (D) Frequency of CD169⁺ cells in the nonclassical (CD14⁺CD16⁺) myeloid subset comparing HC to SLE patients.</p

SLE CD4+ T cell transcriptomes.

<p>Hierarchical cluster dendrogram of expressed genes that differed significantly between sorted peripheral blood CD4+ T cells isolated from SLE patients and healthy controls (HC) as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067003#pone-0067003-g001" target="_blank">figure 1</a>. Also indicated in the columns to the right are differentially expressed genes found in both B cell and T cell compartments of SLE (B FC). Select transcripts are identified for each cluster in boxes (right). For the entire list of transcripts ordered by clusters from the dendrogram see supplementary <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067003#pone.0067003.s008" target="_blank">Table S2</a>.</p

SLE Subsets Up-regulate Unique Transcriptional Profiles.

<p>A Venn diagram demonstrating shared and unique differentially expressed transcripts of SLE myeloid cells, B cells and T cells. Of the 474 combined transcripts only 4.4% (21) were shared by all three subsets, whereas 69% (329) of the transcripts were unique to a particular subset at the threshold set for the described primary analysis.</p