CD4+CD57+ senescent T cells as promoters of systemic lupus erythematosus pathogenesis and the therapeutic potential of senolytic BCL-2 inhibitor.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by persistent activation of immune cells and overproduction of autoantibodies. The accumulation of senescent T and B cells has been observed in SLE and other immune-mediated diseases. However, the exact mechanistic pathways contributing to this process in SLE remain incompletely understood. In this study, we found that in SLE patients: (1) the frequency of CD4+CD57+ senescent T cells was significantly elevated and positively correlated with disease activity; (2) the expression levels of B-lymphoma-2 (BCL-2) family and interferon-induced genes (ISGs) were significantly upregulated; and (3) in vitro, the cytokine IL-15 stimulation increased the frequency of senescent CD4+ T cells and upregulated the expression of BCL-2 family and ISGs. Further, treatment with ABT-263 (a senolytic BCL-2 inhibitor) in MRL/lpr mice resulted in decreased: (1) frequency of CD4+CD44hiCD62L-PD-1+CD153+ senescent CD4+ T cells; (2) frequency of CD19+CD11c+T-bet+ age-related B cells; (3) level of serum antinuclear antibody; (4) proteinuria; (5) frequency of Tfh cells; and (6) renal histopathological abnormalities. Collectively, these results indicated a dominant role for CD4+CD57+ senescent CD4+ T cells in the pathogenesis of SLE and senolytic BCL-2 inhibitor ABT-263 may be the potential treatment in ameliorating lupus phenotypes.

Bach2 in CD4+ T cells from SLE patients modulates B-cell differentiation and IgG production.

T and B cells participate in the development of systemic lupus erythematosus (SLE). BTB and CNC homology 2 (Bach2) is an irreplaceable regulator in the T and B lineages that helps to maintain immune homeostasis. However, the function of Bach2 in the pathogenesis of SLE has not been studied in depth. Flow cytometry and qRT-PCR were used to assess Bach2 levels, bisulfite sequencing PCR was used to measure the methylation level, and silencing by electroporation and stimulation with a cytokine concentration gradient were used to investigate the effect of Bach2 on T cells. Bach2 expression was elevated in the helper T-cell subsets (T follicular helper, Th1, Th2, Th17, and Treg cells) of SLE patients and negatively correlated with disease severity and autoantibody levels. CD4+ T cells from SLE patients had decreased methylation levels in the Bach2 promoter region. Silencing Bach2 in CD4+ T cells induced increases in the CD19+ B-cell count, plasmablasts, and secretion of IgG by prompting the secretion of cytokines. The activation signals CD3/CD28, IL-6, and IL-21 upregulated Bach2 expression in CD4+ T cells. The regulation of Bach2 by cytokines and T-cell activation signals in CD4+ T cells was shown to act on B cells and play a protective role against SLE.

Interferon-α regulates abnormally increased expression of RSAD2 in Th17 and Tfh cells in systemic lupus erythematosus patients.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that often involves abnormal activation of regulatory IFN genes and regulation of B cells by CD4+ T cells. Radical S-adenosyl methionine domain containing 2 (RSAD2) is a viral suppressor protein regulated by type I IFN, and it has been proven to play an important regulatory role in SLE. However, the mechanism by which RSAD2 participates in the pathogenesis of SLE is unclear. In this study, we observed higher expression levels of RSAD2 in CD4+ T-cell subsets from the peripheral blood of SLE patients than in those from healthy controls by bioinformatics analysis and validation experiments. We analyzed the expression of RSAD2 in CD4+ T cells of patients with SLE and other autoimmune diseases. In addition, we found that the expression of RSAD2 in CD4+ T cells might be regulated by IFN-α, and RSAD2 significantly affected the differentiation of Th17 cells and T follicular helper (Tfh) cells. Our findings underlined that RSAD2 may promote B-cell activation by promoting the differentiation of Th17 and Tfh cells in SLE patients, a process that is regulated by IFN-α.

Multi-omics study reveals different pathogenesis of the generation of skin lesions in SLE and IDLE patients.

Lupus erythematosus (LE) is a heterogeneous, antibody-mediated autoimmune disease. Isolate discoid LE (IDLE) and systematic LE (SLE) are traditionally regarded as the two ends of the spectrum, ranging from skin-limited damage to life-threatening multi-organ involvement. Both belong to LE, but IDLE and SLE differ in appearance of skin lesions, autoantibody panels, pathological changes, treatments, and immunopathogenesis. Is discoid lupus truly a form of LE or is it a completely separate entity? This question has not been fully elucidated. We compared the clinical data of IDLE and SLE from our center, applied multi-omics technology, such as immune repertoire sequencing, high-resolution HLA alleles sequencing and multi-spectrum pathological system to explore cellular and molecular phenotypes in skin and peripheral blood from LE patients. Based on the data from 136 LE patients from 8 hospitals in China, we observed higher damage scores and fewer LE specific autoantibodies in IDLE than SLE patients, more uCDR3 sharing between PBMCs and skin lesion from SLE than IDLE patients, elevated diversity of V-J recombination in IDLE skin lesion and SLE PBMCs, increased SHM frequency and class switch ratio in IDLE skin lesion, decreased SHM frequency but increased class switch ratio in SLE PBMCs, HLA-DRB1*03:01:01:01, HLA-B*58:01:01:01, HLA-C*03:02:02:01, and HLA-DQB1*02:01:01:01 positively associated with SLE patients, and expanded Tfh-like cells with ectopic germinal center structures in IDLE skin lesions. These findings suggest a significant difference in the immunopathogenesis of skin lesions between SLE and IDLE patients. SLE is a B cell-predominate systemic immune disorder, while IDLE appears limited to the skin. Our findings provide novel insights into the pathogenesis of IDLE and other types of LE, which may direct more accurate diagnosis and novel therapeutic strategies.

Image-based remote evaluation of PASI scores with psoriasis by the YOLO-v4 algorithm.

As a chronic relapsing disease, psoriasis is characterized by widespread skin lesions. The Psoriasis Area and Severity Index (PASI) is the most frequently utilized tool for evaluating the severity of psoriasis in clinical practice. Nevertheless, long-term monitoring and precise evaluation pose difficulties for dermatologists and patients, which is time-consuming, subjective and prone to evaluation bias. To develop a deep learning system with high accuracy and speed to assist PASI evaluation, we collected 2657 high-quality images from 1486 psoriasis patients, and images were segmented and annotated. Then, we utilized the YOLO-v4 algorithm to establish the model via four modules, we also conducted a human-computer comparison through quadratic weighted Kappa (QWK) coefficients and intra-class correlation coefficients (ICC). The YOLO-v4 algorithm was selected for model training and optimization compared with the YOLOv3, RetinaNet, EfficientDet and Faster_rcnn. The model evaluation results of mean average precision (mAP) for various lesion features were as follows: erythema, mAP = 0.903; scale, mAP = 0.908; and induration, mAP = 0.882. In addition, the results of human-computer comparison also showed a median consistency for the skin lesion severity and an excellent consistency for the area and PASI score. Finally, an intelligent PASI app was established for remote disease assessment and course management, with a pleasurable agreement with dermatologists. Taken together, we proposed an intelligent PASI app based on the image YOLO-v4 algorithm that can assist dermatologists in long-term and objective PASI scoring, shedding light on similar clinical assessments that can be assisted by computers in a time-saving and objective manner.

Overexpressed CD44 is associated with B-cell activation via the HA-CD44-AIM2 pathway in lupus B cells.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by aberrant development of B cells and excess production of autoantibodies. Our team previously reported that absent in melanoma 2 (AIM2) regulates B-cell differentiation via the Bcl-6-Blimp-1 axis. Notably, in keyhole limpet hemocyanin (KLH)-immunized CD19creAim2f/f mice, the frequency of CD19+CD44+ B cells was decreased, accompanied by a weakened KLH response, indicating that AIM2 deficiency suppressed the antigen-induced B-cell immune response by downregulating the expression of CD44. CD44, a surface marker of T-cell activation and memory, was overexpressed in T cells of SLE patients, but its roles and mechanism in B cells have not been elucidated. In the current work, we revealed that CD44 expression was upregulated in the B cells of SLE patients and MRL/lpr mice, accompanied by elevated AIM2 expression in CD19+CD44+ B-cell subsets, and that its ligand hyaluronan (HA) was also abnormally increased in the serum of SLE patients. Notably, the extrafollicular (EF) region serves as an important site of B-cell activation and differentiation separate from the germinal center, while CD44 expression is concentrated in EF B cells. In addition, in vitro experiments demonstrated that the HA-CD44 interaction stimulated B-cell activation and upregulated the expression of AIM2 and the transcription factor STAT3. Either blocking CD44, knocking down AIM2 expression or suppressing the activity of STAT3 in B cells suppressed B-cell activation and proliferation. Moreover, blocking CD44 downregulated the expression of STAT3 and AIM2, while suppressing the activity of STAT3 decreased the expression of CD44 and AIM2. In summary, overexpressed CD44 in B cells might participate in B-cell activation and proliferation in the EF region via the HA-CD44-AIM2 pathway, providing potential targets for SLE therapy.

Systemic lupus erythematosus patients contain B-cell receptor repertoires sensitive to immunosuppressive drugs.

Immune repertoire (IR) during treatment may be a surrogate biomarker for disease response. Changes of the IR in systemic lupus erythematosus patients in response to immunosuppressive drugs were identified in ten SLE patients. Patients provided peripheral blood mononuclear cells at two time points for sequencing. They were divided into sensitive and nonsensitive groups by their clinical responses to immunosuppressive drugs. After treatment, the BCR expression significantly decreased in patients from the sensitive group while there was no change in patients from the nonsensitive group. IgM comprised a dominant portion of the BCR repertoire and increased slightly in all patients in the sensitive group but decreased in the nonsensitive group. IgA also exhibited opposing changes between the two groups. Shorter CDR3 of TRB and TRG chains occurred in the sensitive group. CDR3 length of IGK decreased significantly in the sensitive group. CDR3 of TCR δ/γ changed distinctly between time points in the sensitive group. Six immune-related genes showed differential expression levels in sensitive and nonsensitive groups. Our study shows that it is BCR repertoire sensitivity to immunosuppressive drugs in SLE patients and sheds light on personalized therapy for SLE.

Immune repertoire sequencing reveals an abnormal adaptive immune system in COVID-19 survivors.

Accumulating evidence suggests that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impairs the adaptive immune system during acute infection. Still, it remains largely unclear whether the frequency and functions of T and B cells return to normal after the recovery of Coronavirus Disease 2019 (COVID-19). Here, we analyzed immune repertoires and SARS-CoV-2-specific neutralization antibodies in a prospective cohort of 40 COVID-19 survivors with a 6-month follow-up after hospital discharge. Immune repertoire sequencing revealed abnormal T- and B-cell expression and function with large T cell receptor/B cell receptor clones, decreased diversity, abnormal class-switch recombination, and somatic hypermutation. A decreased number of B cells but an increased proportion of CD19+ CD138+ B cells were found in COVID-19 survivors. The proportion of CD4+ T cells, especially circulating follicular helper T (cTfh) cells, was increased, whereas the frequency of CD3+ CD4- T cells was decreased. SARS-CoV-2-specific neutralization IgG and IgM antibodies were identified in all survivors, especially those recorded with severe COVID-19 who showed a higher inhibition rate of neutralization antibodies. All severe cases complained of more than one COVID-19 sequelae after 6 months of recovery. Overall, our findings indicate that SARS-CoV-2-specific antibodies remain detectable even after 6 months of recovery. Because of their abnormal adaptive immune system with a low number of CD3+ CD4- T cells and high susceptibility to infections, COVID-19 patients might need more time and medical care to fully recover from immune abnormalities and tissue damage.

Sirtuin 1 overexpression contributes to the expansion of follicular helper T cells in Systemic lupus erythematosus and serves as an easy-to-intervene therapeutic target.

OBJECTIVE: SIRT1, an NAD+-dependent deacetylase, is up-regulated in CD4+ T cells from SLE patients and MRL/lpr lupus-like mice. This study aimed to explore the role of SIRT1 in Tfh cell expansion and its potential value as a therapeutic target for SLE. METHODS: Frequencies of CD4+CXCR5+PD-1+ Tfh cells in peripheral blood from SLE patients and their expression of SIRT1 and BCL-6 were determined with flow cytometry. Naïve CD4+ T cells were transfected with SIRT1-expressing lentivirus and small interfering RNA (siRNA) targeting SIRT1, respectively, and then cultured in a Tfh-polarizing condition to study the impact of SIRT1 on Tfh cell differentiation. This impact was also evaluated in both CD4+ T cells and naïve CD4+ T cells by treatment with SIRT1 inhibitors (EX527 and nicotinamide) in vitro. MRL/lpr mice and pristane-induced lupus mice were treated with continuous daily intake of nicotinamide, and their lupus phenotypes including skin rash, arthritis, proteinuria and serum anti-dsDNA autoantibodies were compared with controls. RESULTS: Expression of SIRT1 was elevated in Tfh cells from SLE patients and positively correlated with Tfh cell frequencies. SIRT1 expression gradually increased during Tfh cell differentiation. Overexpression of SIRT1 by lentiviral vectors significantly promoted Tfh cell differentiation/proliferation. Reciprocally, suppressing expression of SIRT1 by siRNA and inhibiting SIRT1 activity by EX-527 or nicotinamide hindered Tfh cell expansion. Continuous daily intake of nicotinamide alleviated lupus-like phenotypes and decreased serum CXCL13 in the two mouse models. CONCLUSION: SIRT1 overexpression contributes to the expansion of Tfh cells in SLE and may serve as a potential target for treatment.

A 2-week time-restricted feeding attenuates psoriasis-like lesions with reduced inflammatory cytokines and immunosenescence in mice.

Psoriasis, a well-established T-cell mediated dermatosis, exhibits a robust correlation with obesity and systemic inflammation, manifesting psoriasis skin lesions and premature immunosenescence within the peripheral blood and lesion. Intermittent fasting (IF) has exhibited various beneficial effects in reducing inflammation, resisting oxidative stress and slowing ageing, as well as losing weight. A form of IF known as time-restricted feeding (TRF) restricts daily caloric intake within 4-8 h. Nonetheless, the advantageous impacts of TRF on psoriasis still require further verification. We measured the acanthosis in Imiquimod (IMQ)-induced psoriasis mice and evaluated their pathological phenotypes. Our study examined the effects of a 2-week TRF on body weight and metabolic parameters. The subsets of T cells in spleens and skin lesions were accessed by flow cytometry. Cytokines and senescence-associated genes were evaluated by immunofluorescence and RT-qPCR. RNA sequencing was conducted on skin lesions. According to our findings, a 2-week TRF attenuates psoriasis-like lesions in mice with reduced inflammatory cytokines and mitigated immunosenescence. TRF increased the counts of CD4+ Treg cells in skin lesions while reducing the counts of Th2 and Th17 cells in spleens. Furthermore, the administration of TRF resulted in a decrease in the population of CD4+ senescent T cells in both the dermis and spleens, concomitant with the expression of senescence-associated genes in spleen CD4+ T cells. The outcomes mentioned above provide valuable evidence in support of TRF for the management of psoriasis.

Dynamic hippocampal functional connectivity responses to varying working memory loads following total sleep deprivation.

Sleep loss with work overload can impact human cognitive performance. However, the brain's response to an increased working memory load following total sleep deprivation (TSD) remains unclear. In the present study, we focussed on the dynamic response of the hippocampus to increased working memory load before and after total sleep deprivation of 36 h. A total of 16 male participants completed a verbal working memory task under functional magnetic resonance imaging. After whole-brain activation analysis and region of interest analysis of the hippocampus, the generalised form of context-dependent psychophysiological interactions (gPPI) was used to analyse the hippocampal functional connectivity with the whole brain. The results revealed that as the working memory load increased within a small range, from 0-back to 1-back task, the left hippocampal functional connectivity decreased with the left supplementary motor area, left pars opercularis, left rolandic operculum, right superior frontal gyrus, bilateral precentral gyrus, and left middle cingulate cortex following total sleep deprivation compared with that observed in resting wakefulness. When the working memory load further increased from 1-back to 2-back task, the connectivity increased between the left hippocampus and the left superior parietal lobule as well as between the left hippocampus and right lingual gyrus after total sleep deprivation compared with that observed in resting wakefulness. Moreover, the left hippocampus gPPI effect on the left middle cingulate cortex and left superior parietal lobule could predict the behavioural test accuracy in 1-back and 2-back task, respectively, following total sleep deprivation. These findings indicated that increased working memory load after total sleep deprivation disrupts working memory processes. The brain reacts to these disruptions in a dynamic and flexible manner, involving not only brain activation but also hippocampus-related functional network connections.

Locoregional therapy for oligometastatic cervical cancer: a single-center retrospective study.

BACKGROUND: Oligometastases are limited in number and extent, and therefore, are amenable to locoregional therapy. OBJECTIVE: To analyze recurrence patterns, survival outcomes, and prognostic factors in patients with cervical cancer receiving locoregional therapy for oligometastases. METHODS: The included patients had 1-3 extracranial oligometastases and received definitive radiotherapy, surgery, or ablation at a single institution between January 2007 and May 2022. Outcomes were evaluated using the Kaplan-Meier method. Prognostic factors were examined using the Cox proportional hazards model, and tumor growth rates were predicted by non-linear regression. RESULTS: We identified 56 patients who presented with an oligometastatic disease to the supraclavicular fossa (n=19), lung (n=33), or other sites (n=4). Totals of 30 (53.6%), 41 (73.2%), 47 (83.9%), and 52 (92.9%) patients were diagnosed 1, 2, 3, and 4 years after cervical cancer diagnosis, respectively. Seven patients were simultaneously treated for para-aortic or pelvic recurrences. After a median follow-up of 24 months (range 1-86), the 3-year local recurrence-free rate in patients with supraclavicular versus non-supraclavicular oligometastases was 100% vs 93.5%. The 3-year overall survival rate was 40.1% vs 55.2% (p=0.04). Ten (17.9%) patients experienced new oligometastatic progression in a median of 8 months (range 4-14). Multivariate analysis showed that tumor size was the only prognostic factor for overall survival, with a 3-year overall survival rate of 91.7% vs 21.6% (≤15 mm vs >15 mm, p<0.001). Nineteen (86.4%) of 22 lesions diagnosed within 6 months of the last negative CT scan had a maximum diameter of ≤15 mm, and the predicted interval of tumor growth to 15 mm was 5.8 months. CONCLUSION: Locoregional therapy for cervical cancer oligometastases can achieve long-term survival, especially in patients with small lesions (≤15 mm). Better follow-up mode after cervical cancer treatment and system therapy for oligometastases should be further explored.

Skin CD4+ Trm cells distinguish acute cutaneous lupus erythematosus from localized discoid lupus erythematosus/subacute cutaneous lupus erythematosus and other skin diseases.

BACKGROUND: Although the contribution of aberrant CD4+ T cell signaling to systemic lupus erythematosus (SLE) is well established, its role in cutaneous lupus erythematosus (CLE) skin is largely unknown. Because the rate of systemic manifestations varies in each subtype, resident memory CD4+ T cells in lesions that are responsible for only skin-associated tissue responses may vary in each subtype. However, the role of CD4+ tissue-resident memory T (CD4+ Trm) cells in each CLE subtype remains unclear. OBJECTIVES: To analyze and compare CD4+ Trm cells and absent in melanoma 2 (AIM2) identified by smart RNA sequencing (Smart-seq) in CD4+ Trm cells from patients with acute CLE (ACLE), subacute CLE (SCLE), and localized discoid lupus erythematosus (localized DLE) lesions. METHODS: We performed Smart-seq to investigate differences in dermal CD4+ Trm cells between patients with ACLE and normal controls (NCs). Multicolor immunohistochemistry was utilized to measure the levels of AIM2 in CD4+ Trm cells present in the skin of 134 clinical patients, which included patients with localized DLE (n = 19), ACLE (n = 19), SCLE (n = 16), psoriasis (n = 12), rosacea (n = 17), lichen planus (n = 18), and annular granuloma (n = 15), as well as NCs (n = 18). RESULTS: The Smart-seq data showed higher AIM2 expression in skin CD4+ Trm cells from ACLE lesions than NCs (fold change >10, adjusted P < 0.05). AIM2 expression in CD4+ Trm cells did not vary according to age or sex. AIM2 expression in CD4+ Trm cells was significantly lower in patients with ACLE (6.38 ± 5.22) than localized DLE (179.41 ± 160.98, P < 0.0001) and SCLE (63.43 ± 62.27, P < 0.05). In an overall comparison of ACLE with localized DLE and SCLE, the receiver operating characteristic curve for AIM2 expression in CD4+ Trm cells had a sensitivity of 100.00% and a specificity of 82.86% at a cutoff value of 18.26. In a comparison of ACLE with localized DLE, the sensitivity was 89.47%, and the specificity was 100.00% at a cutoff value of 12.26. In a comparison of ACLE with SCLE, the sensitivity was 100.00%, and the specificity was 75.00% at a cutoff value of 18.26. CONCLUSIONS: The number of CD4+ Trm cells is increased in lesions of SCLE and localized DLE compared to ACLE, suggesting that CD4+ Trm cells may have a more crucial role in persistent lesions of SCLE and localized DLE. In addition, AIM2 expression in CD4+ Trm cells discriminates patients with ACLE from those with localized DLE and SCLE.

Safety and efficacy of fecal microbiota transplantation for treatment of systemic lupus erythematosus: An EXPLORER trial.

Gut microbiota dysbiosis is involved in the development of systemic lupus erythematosus (SLE). The safety and efficacy of fecal microbiota transplantation (FMT) for the treatment of SLE patients has not been explored. In this 12-week, single-arm pilot clinical trial of oral encapsulated fecal microbiome from healthy donors to patients with active SLE, we aimed to evaluate the safety and efficacy of FMT in patients with SLE (ChiCTR2000036352). 20 SLE patients with SLEDAI ≥6 were recruited. FMT was administered once a week for three consecutive weeks along with standard treatment and the patients were followed for 12 weeks. Safety was evaluated throughout the trial. The primary endpoint was the SLE Responder Index-4 (SRI-4) at week 12. Microbiome composition, levels of short chain fatty acids (SCFAs) in the gut and of cytokines in the sera were measured along with lymphocyte phenotyping. No serious adverse events were observed after FMT. At week 12, the SRI-4 response rate was 42.12%, and significant reductions in the SLEDAI-2K scores and the level of serum anti-dsDNA antibody were observed compared to baseline. Significant enrichment of SCFAs-producing bacterial taxa and reduction of inflammation-related bacterial taxa were observed, along with increased production of SCFAs in the gut and reduced levels of IL-6 and CD4+ memory/naïve ratio in the peripheral blood. Furthermore, SRI-4 responding patients displayed specific microbiota signatures both before and after FMT. The first clinical trial of FMT in active SLE patients provide supportive evidence that FMT might be a feasible, safe, and potentially effective therapy in SLE patients by modifying the gut microbiome and its metabolic profile.

Tight correlation of 5-hydroxymethylcytosine expression with the scarring damage of discoid lupus erythematosus.

OBJECTIVE: Cutaneous lupus erythematosus (CLE) is a heterogenous skin disease. The two most common subtypes are discoid LE (DLE) characterized by scarring skin damage and acute CLE (ACLE) presenting with transiently reversible skin lesions. It remains unknown what causes the difference of skin lesions. Studies have shown the existence of tissue-specific 5-Hydroxymethylcytosine (5 hmC)-modified regions in human tissues, which may affect the tissue-related diseases. Here, we aim to assess the expression of 5 hmc in DLE and ACLE lesions and explore the relationship of 5 hmc with scarring damage in DLE. METHODS: 84 CLE samples were included in the study. We evaluated the skin damage score and reviewed the histopathologic sections. Immunohistochemical staining was performed to detect the expression of 5 hmc in the appendage and periappendageal inflammatory cells. The 5 hmc expression in periappendageal lymphocytic cells was investigated by multi-spectrum immunohistochemistry staining. RESULTS: Scarring/atrophy was the most significant damage in differentiating the DLE from ACLE. Perifollicular inflammatory infiltration was present in all patients with DLE scarring alopecia (DLESA). The 5 hmc expression in the appendage and periappendageal inflammatory cells was significantxly increased in DLESA than ACLE. Similar expression pattern was seen in the staining of IFN-alpha/beta Receptor (IFNAR). The expression of 5 hmc in the appendage was positively correlated with that in the periappendageal inflammatory cells. There was an increased 5 hmc expression in lymphocytes cluster around hair follicle consisting of CD4+ cells, CD8+ cells, and CD19+ cells in DLESA lesions. CONCLUSION: These data demonstrate a close association of the expression pattern of 5 hmc with the histopathological characteristic distribution, and with the type I interferons (IFNs) signals in DLESA, supporting the importance of 5 hmc in the amplification of appendage damage and periappendageal inflammation, thereby offering a novel insight into the scarring damage of DLE and the heterogeneity of CLE skin lesions.

An Enhanced Expression Level of CXCR3 on Tfh-like Cells from Lupus Skin Lesions Rather Than Lupus Peripheral Blood.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease, and the etiopathogenesis is unclear. Follicular helper T (Tfh) cells have been reported as an important pathogenic cell type in SLE. CXCR3 was reported to be decreased on lupus peripheral CD4+T cells. However, the expression level of CCR4, CCR6 and CXCR3 on Tfh-like cells in SLE peripheral blood and skin lesions is unknown. In this study, we detected CCR4, CCR6 and CXCR3 expression level on Tfh-like cells in the peripheral blood and skin lesions from SLE patients and normal controls (NCs). A decreased expression level of CXCR3 on Tfh-like cells was found in lupus peripheral blood. However, an increased CXCR3 expression was observed on total CD4+T and Tfh-like cells from lupus skin lesions. Moreover, we observed a higher expression level of CXCR3 in Tfh cells from human tonsils. These findings indicate that CXCR3 might help Tfh-like cells to migrate into the inflammatory sites.

A novel humanized cutaneous lupus erythematosus mouse model mediated by IL-21-induced age-associated B cells.

Cutaneous lupus erythematosus (CLE) is a relapsing autoimmune disease, but key elements that drive disease initiation and progression remain elusive. To date, the lack of ideal murine model which resemble human cutaneous lupus makes it extremely challenging for moving mechanistic discoveries and novel therapeutics. Here, we prompt a humanized murine model to develop an inducible rapid-onset murine that performs cutaneous rather than systemic lupus, depending on the successful human immune system reconstruction from active lupus patients and UVB irradiation as for essentially pathogenic triggers. In addition, we demonstrate a newly discovered population of B cell with a unique phenotype, that of the age-associated B cell (ABC, T-bet+ CD11b+), exhibits B cell clusters in humanized cutaneous lupus. In the response of IL-21 and TLR7/9 signals, recruitment of autoreactive B cells to the position of inflammation with subsequent localized antibody production of IgG2a, IgG2b, IgG3, has the potential to exacerbate ongoing inflammation and thus driving lupus-like autoimmunity in a B-cell-dominant fashion. Overall, our model provides a relevant system for exploring the pathophysiology of cutaneous lupus, a suitable model for drug development, as well as updating a potential role of IL-21 and TLR7/9 to be targeted by biologics.

A simple and highly efficient method of IFI44L methylation detection for the diagnosis of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a complex heterogenous autoimmune disease that can be challenging to diagnose. We previously identified the IFN-induced protein 44-like (IFI44L) methylation marker for SLE diagnosis, which can be detected by pyrosequencing. Although the previous technique has high sensitivity and specificity, it requires special equipment and high cost for detection. Here, we established a high-resolution melting-quantitative polymerase chain reaction (HRM-qPCR) assay to detect the methylation of IFI44L promoter for the diagnosis of SLE. The result was determined according to the standard melting curve of the methylation level of the IFI44L promoter region. The sensitivity was 88.571% and the specificity was 97.087%. The HRM-qPCR and pyrosequencing results presented good consistency when both methods were used to detect the methylation of the IFI44L promoter for SLE diagnosis. Furthermore, the HRM-qPCR method can be used to distinguish SLE from other autoimmune diseases, infectious diseases and virus-related cancers.

Clinical significance of miRNAs in autoimmunity.

MicroRNAs (miRNAs) are evolutionally conserved, single-stranded RNAs that regulate gene expression at the posttranscriptional level by disrupting translation. MiRNAs are key players in variety of biological processes that regulate the differentiation, development and activation of immune cells in both innate and adaptive immunity. The disruption and dysfunction of miRNAs can perturb the immune response, stimulate the release of inflammatory cytokines and initiate the production of autoantibodies, and contribute to the pathogenesis of autoimmune diseases, including systemic lupus erythmatosus (SLE), rheumatoid arthritis (RA), primary biliary cholangitis (PBC), and multiple sclerosis (MS). Accumulating studies demonstrate that miRNAs, which can be collected by noninvasive methods, have the potential to be developed as diagnostic and therapeutic biomarkers, the discovery and validation of which is essential for the improvement of disease diagnosis and clinical monitoring. Recently, with the development of detection tools, such as microarrays and NGS (Next Generation Sequencing), large amounts of miRNAs have been identified and suggest a critical role in the pathogenesis of autoimmune diseases. Several miRNAs associated diagnostic biomarkers have been developed and applied clinically, though the pharmaceutical industry is still facing challenges in commercialization and drug delivery. The development of miRNAs is less advanced for autoimmune diseases compared with cancer. However, drugs that target miRNAs have been introduced as candidates and adopted in clinical trials. This review comprehensively summarizes the differentially expressed miRNAs in several types of autoimmune diseases and discusses the role and the significance of miRNAs in clinical management. The study of miRNAs in autoimmunity promises to provide novel and broad diagnostic and therapeutic strategies for a clinical market that is still in its infancy.

Disordered cutaneous microbiota in systemic lupus erythematosus.

The correlation between systemic lupus erythematosus (SLE) and microbiota colonization has been receiving much attention during recent years. Here, we screened the cutaneous bacterial spectrums of 69 SLE patients, 49 healthy controls and 20 dermatomyositis (DM) patients and identified the specific changes of cutaneous microbial composition and abundance in SLE patients. We observed the decreasing diversity in community richness and evenness and the greater heterogeneity in SLE patients compared to healthy controls, which were also different from the cutaneous microbiome of DM patients. The skin microbial community disorders in SLE patients were correlated with several clinical features such as serum low complement level, gender, renal involvement and myositis. According to the Kruskal-Wallis (KW) test, receiver operating characteristic (ROC) curve and LDA Effect Size (LEfSe) analysis, several bacterial taxa such as Staphylococcus, especially Staphylococcus aureus and Staphylococcus epidermidis, were identified to be potential markers for SLE skin lesions. Furthermore, Picrust analysis showed that Staphylococcus aureus infection pathway was significantly enriched and exhibited a strong correlation with genus Staphylococcus in SLE patients. The changes in the composition and abundance of cutaneous microbiota in SLE patients suggest that the microbial dysbiosis is associated with the pathogenesis of SLE, which may be potentially reliable biomarker or therapeutic target for SLE.