Evaluation of immune profiles associated with control of mycobacterial growth in systemic lupus erythematosus (SLE) patients.

Tuberculosis (TB) is an infectious disease with the burden concentrated in low- and middle-income countries. Systemic lupus erythematosus (SLE) is an autoimmune disease associated with widespread inflammation that is prevalent in some TB endemic areas including East Africa and parts of Southeast Asia. SLE patients are known to be at higher risk of becoming infected with M. tb, developing TB disease. However, the immune mechanisms underlying this susceptibility are not well understood, particularly in the absence of immunosuppressive drugs. We present a pilot study in which we have evaluated intracellular cytokine responses and ex vivo ability to control mycobacterial growth using peripheral blood mononuclear cells (PBMC) collected from SLE patients before and during SLE treatment. After six months of treatment, SLE patients had the highest frequencies of CD8+ T cells, NK cells and NKT cells producing IFN-γ and/or TNF-α. This group also showed superior control of mycobacterial growth, and proinflammatory cytokine-producing NK and NKT cells correlated with mycobacterial growth inhibition at the individual patient level. These findings contribute to a better understanding of autoimmune profiles associated with control of mycobacterial growth in SLE patients, which may inform intervention strategies to reduce risk of TB disease in this population.

Gut Microbiota Dysbiosis in Systemic Lupus Erythematosus: Novel Insights into Mechanisms and Promising Therapeutic Strategies.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that was traditionally thought to be closely related to genetic and environmental risk factors. Although treatment options for SLE with hormones, immunosuppressants, and biologic drugs are now available, the rates of clinical response and functional remission of these drugs are still not satisfactory. Currently, emerging evidence suggests that gut microbiota dysbiosis may play crucial roles in the occurrence and development of SLE, and manipulation of targeting the gut microbiota holds great promises for the successful treatment of SLE. The possible mechanisms of gut microbiota dysbiosis in SLE have not yet been well identified to date, although they may include molecular mimicry, impaired intestinal barrier function and leaky gut, bacterial biofilms, intestinal specific pathogen infection, gender bias, intestinal epithelial cells autophagy, and extracellular vesicles and microRNAs. Potential therapies for modulating gut microbiota in SLE include oral antibiotic therapy, fecal microbiota transplantation, glucocorticoid therapy, regulation of intestinal epithelial cells autophagy, extracellular vesicle-derived miRNA therapy, mesenchymal stem cell therapy, and vaccination. This review summarizes novel insights into the mechanisms of microbiota dysbiosis in SLE and promising therapeutic strategies, which may help improve our understanding of the pathogenesis of SLE and provide novel therapies for SLE.

The interplay between host genetics and the gut microbiome reveals common and distinct microbiome features for complex human diseases.

BACKGROUND: Interest in the interplay between host genetics and the gut microbiome in complex human diseases is increasing, with prior evidence mainly being derived from animal models. In addition, the shared and distinct microbiome features among complex human diseases remain largely unclear. RESULTS: This analysis was based on a Chinese population with 1475 participants. We estimated the SNP-based heritability, which suggested that Desulfovibrionaceae and Odoribacter had significant heritability estimates (0.456 and 0.476, respectively). We performed a microbiome genome-wide association study to identify host genetic variants associated with the gut microbiome. We then conducted bidirectional Mendelian randomization analyses to examine the potential causal associations between the gut microbiome and complex human diseases. We found that Saccharibacteria could potentially decrease the concentration of serum creatinine and increase the estimated glomerular filtration rate. On the other hand, atrial fibrillation, chronic kidney disease and prostate cancer, as predicted by host genetics, had potential causal effects on the abundance of some specific gut microbiota. For example, atrial fibrillation increased the abundance of Burkholderiales and Alcaligenaceae and decreased the abundance of Lachnobacterium, Bacteroides coprophilus, Barnesiellaceae, an undefined genus in the family Veillonellaceae and Mitsuokella. Further disease-microbiome feature analysis suggested that systemic lupus erythematosus and chronic myeloid leukaemia shared common gut microbiome features. CONCLUSIONS: These results suggest that different complex human diseases share common and distinct gut microbiome features, which may help reshape our understanding of disease aetiology in humans. Video Abstract.

The CD38/NAD/SIRTUIN1/EZH2 Axis Mitigates Cytotoxic CD8 T Cell Function and Identifies Patients with SLE Prone to Infections.

Patients with systemic lupus erythematosus (SLE) suffer frequent infections that account for significant morbidity and mortality. T cell cytotoxic responses are decreased in patients with SLE, yet the responsible molecular events are largely unknown. We find an expanded CD8CD38high T cell subset in a subgroup of patients with increased rates of infections. CD8CD38high T cells from healthy subjects and patients with SLE display decreased cytotoxic capacity, degranulation, and expression of granzymes A and B and perforin. The key cytotoxicity-related transcription factors T-bet, RUNX3, and EOMES are decreased in CD8CD38high T cells. CD38 leads to increased acetylated EZH2 through inhibition of the deacetylase Sirtuin1. Acetylated EZH2 represses RUNX3 expression, whereas inhibition of EZH2 restores CD8 T cell cytotoxic responses. We propose that high levels of CD38 lead to decreased CD8 T cell-mediated cytotoxicity and increased propensity to infections in patients with SLE, a process that can be reversed pharmacologically.

The diagnostic values of C-reactive protein and procalcitonin in identifying systemic lupus erythematosus infection and disease activity.

To explore the values of C-reactive protein (CRP) and procalcitonin (PCT) in identifying infection and disease activity in systemic lupus erythematosus (SLE) patients.Patients with SLE and infection from April 2015 to January 2018 were included in this study. We compared the clinical characteristics and biomarkers between different groups and calculated the receiver operating characteristic curve, sensitivity, and specificity of the corresponding biomarkers. Logistic regression analysis was performed on the variables exhibiting significant differences in univariate analysis.A total of 177 SLE patients were retrospectively analyzed. The patients were divided into noninfected-inactive group, noninfected-active group, infected-inactive group, and infected-active group. CRP level of infected-inactive group was significantly higher than noninfected-inactive group (P < .05), but not significantly in infected-active group than noninfected-active group (P > .05). Multivariate analysis showed that CRP (>24.0 mg/L) was the only independent risk factor for SLE infection (odds ratio, OR = 2.896, P = .032). PCT level of infected-active group was significantly higher than infected-inactive group (P < .05), but not significantly in noninfected-active group than noninfected-inactive group (P > .05). SLE active group had shorter disease course, lower infection rate, higher PCT level, and lower platelet count (PLT). Multivariate logistic analysis showed that PCT (>0.048 ng/mL) and PLT (<150 × 10/L) were independent risk factors for SLE activity (OR = 3.498 and 4.391, P = .011 and 0.009), and disease course (>96 months) was independent protective factor (OR = 0.169, P < .001). The area under the curve of the logistic model was significantly larger than any single variable (all P < .05).CRP is the only effective marker for diagnosing infection in SLE patients. Moreover, PCT helps predict SLE activity.

Disseminated Nocardia farcinica infection presenting as a paravertebral abscess in a patient with systemic lupus erythematosus.

Disseminated Nocardia infections occur particularly in immunosuppressed hosts and are most often due to Nocardia farcinica, Nocardia nova, and Nocardia cyriacigeorgica. Here, we report an unusual case of disseminated N. farcinica infection presenting as a paravertebral abscess in a patient with systemic lupus erythematosus.

Sex, Symptom Severity, and Quality of Life in Rheumatology.

Inflammatory rheumatic diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) show a striking female predominance ranging from 3:1 in RA up to 9:1 in SLE. The background for those gender bias is not fully understood yet, but seems to be the result of a complex interaction between sex hormones, (epi-)genetics, and possibly even the composition of gut microbiota. Moreover, time of disease onset, the clinical phenotype including co-morbidities as well as the course of the diseases during life differ between genders. The patient's sex therefore plays an emerging role for individual therapy decisions and co-morbidity screening in rheumatologic care. Male lupus patients, for example, tend to show more severe features such as renal involvement, pleurisy, and serositis, when being compared to female patients. Among RA patients, women are more likely to acquire conditions like thyroid dysfunctions, fibromyalgia, and depression than their male counterparts. These examples emphasize the importance of the patient's gender for the clinical routine and the resulting implications for prevention and therapy. The present article is going to review potential causes for the female predominance of rheumatic diseases and will examine the gender's impact on the disease phenotype, symptom severity, co-morbidities, and quality of life. For reasons of scope, the focus will be on RA and SLE as two of the most important rheumatic diseases with a large socioeconomic impact on society due to their incidence as well as mortality.

Amelioration of regulatory T cells by Lactobacillus delbrueckii and Lactobacillus rhamnosus in pristane-induced lupus mice model.

Regulatory T cells (Tregs) play an indispensable role in the control of immune responses and induction of peripheral tolerance. Dysregulation of Tregs is involved in the pathogenesis of systemic lupus erythematosus (SLE). Tolerogenic probiotics have shown beneficial effects in the control of autoimmune diseases. We evaluated the prophylactic and therapeutic effects of Lactobacillus delbrueckii and Lactobacillus rhamnosus on Tregs and their related molecules in pristane-induced lupus mice model. Fifty-four female BALB/c mice (3-5 weeks) were randomly divided into nine groups. Lupus was induced in all groups using pristane. Prophylactic groups were treated from Day 0 (at the time of pristane injection) and treatment groups were treated 2 months later with L. rhamnosus, L. delbrueckii, mix of both probiotics, and prednisolone. One group was considered as SLE-induced control group without any treatment. Presence of antinuclear antibodies (ANA), antidouble-stranded DNA (anti-dsDNA), antiribonucleoprotein (anti-RNP), proteinuria, and serum level of creatinine, urea, the expression of forkhead box P3 (Foxp3), interleukin 6 (IL-6), IL-10, transforming growth factor ß, and the number of Tregs were determined. SLE induction by pristane led to the formation of lipogranuloma, presence of ANA, anti-dsDNA, and anti-RNP. Probiotics consumption decreased the level of lipogranuloma, ANA, and anti-dsDNA. In addition, in probiotics receiving groups, Tregs and the expression level of Foxp3 increased, while IL-6 decreased. The effect of probiotics in the prophylactic group was more prominent. The results may indicate the effectiveness of L. delbrueckii and L. rhamnosus in the enhancement of Tregs and the decrease of inflammatory cytokines and disease severity in SLE-induced mice.

A suppurative thyroiditis and perineal subcutaneous abscess related with aspergillus fumigatus: a case report and literature review.

BACKGROUND: Invasive aspergillosis is a complication in immunocompromised patients and commonly detected in patients with hematological malignancies, which mostly affect the lungs. Because of its high iodine content, rich blood supply and capsule, the thyroid is considered to be less prone to microbial invasion thus most infectious thyroiditis cases are caused by bacteria. However, a few case reports have described thyroid gland aspergilloses, most of which were due to disseminated invasive aspergillosis. CASE PRESENTATION: We first report a case of thyroid gland and subcutaneous labium majus aspergillosis in a Chinese patient who received long-term glucocorticoid treatment for systemic lupus erythematosus (SLE) and lupus nephritis, and then we reviewed 36 articles describing similar aspergillus infections in 41 patients. CONCLUSION: We included 29 cases of diagnosed aspergillus thyroiditis and analyzed clinical findings, treatments and outcomes to provide clinical information for diagnosis and prognosis of thyroiditis caused by Aspergillus fumigatus.

Disseminated extrapulmonary Legionella pneumophila infection presenting with panniculitis: case report and literature review.

BACKGROUND: Legionellosis is a well-known cause of pneumonia. Primary cutaneous and subcutaneous infection caused by Legionella pneumophila is rare and the diagnosis is challenging. CASE PRESENTATION: A 38-year-old Thai woman with systemic lupus erythematosus and myasthenia gravis treated with prednisolone and azathioprine presented to our hospital with low-grade fever, diarrhea, and indurated skin lesions on both thighs. Initial examination showed plaques on both inner thighs. Magnetic resonance imaging showed myositis and swelling of the skin and subcutaneous tissue. Diagnosis of panniculitis due to L. pneumophila was carried out by histopathology, Gram stain, and 16S rRNA gene sequencing method of tissue biopsy from multiple sites on both thighs. Myocarditis was diagnosed by echocardiography. The final diagnosis was disseminated extrapulmonary legionellosis. Treatment comprised intravenous azithromycin for 3 weeks and the skin lesions, myositis and myocarditis resolved. Oral azithromycin and ciprofloxacin were continued for 3 months to ensure eradication of the organism. The patient's overall condition improved. CONCLUSIONS: To our knowledge, we report the first case of L. pneumophila infection manifesting with panniculitis, possible myositis, and myocarditis in the absence of pneumonia. The diagnosis of extrapulmonary Legionella infection is difficult, especially in the absence of pneumonia. A high index of suspicion and appropriate culture with special media or molecular testing are required. Initiation of appropriate treatment is critical because delaying therapy was associated with progressive infection in our patient.

Generation of tolerogenic dendritic cells using Lactobacillus rhamnosus and Lactobacillus delbrueckii as tolerogenic probiotics.

Systemic lupus erythematosus (SLE) concurs with excessive uncontrolled inflammatory immune responses that lead to the loss of immune tolerance. Dendritic cells (DCs) are important and determinant immune cells that regulate immune responses. Tolerogenic DCs with regulatory markers and cytokines could induce regulatory immune cells and responses. Tolerogenic probiotics are capable of producing regulatory DCs from monocytes in in vitro conditions. The purpose of this study was to evaluate the effect of Lactobacillus delbrueckii and Lactobacillus rhamnosus on the production of DCs in an in vitro condition. Peripheral blood mononuclear cells were isolated from the healthy and SLE donors. Monocytes were cultured with optimized concentrations of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) to produce immature DCs (IDCs). An IDC uptake assay was performed, and IDCs of healthy and SLE donors were divided into three subgroups following 48 hours of treatment with GM-CSF and IL-4, along with L. delbrueckii, L. rhamnosus, and mixed probiotics for the production of tolerogenic DCs. The surface expression of Human Leukocyte Antigen-antigen D Related (HLA-DR), CD86, CD80, CD83, CD1a, and CD14 was analyzed using flow cytometry, and the gene expression levels of indoleamine 2,3-dioxygenase (IDO), IL-10, and IL-12 were measured using real-time polymerase chain reaction. We observed significantly reduced expression of costimulatory molecules and other surface markers in the probiotic-induced mature DCs (MDCs) in both healthy and SLE donor groups in comparison with lipopolysaccharide (LPS)-induced MDCs. In addition, the expression of IDO and IL-10 increased, whereas IL-12 decreased significantly in probiotic-induced MDCs compared with LPS-induced MDCs. IDCs and especially mature tolerogenic DC of SLE patients highly expressed IDO. The results of the current study suggested that live probiotics could modify properties of DCs to modulatory cells, which might contribute to the induction of tolerance and renovation of immune hemostasis.

O impacto do lúpus eritematoso sistêmico juvenil na inflamação gengival: achados clínicos, imunológicos e microbiológicos / The impact of juvenile systemic lupus erythematosus on gingival inflammation: clinical, immunological and microbiological findings

Os objetivos desse estudo foram avaliar a expressão de citocinas no soro e fluido gengival, a produção de arginina-peptidil-deiminase (anti-PPAD) e o perfil microbiológico de pacientes com lúpus eritematoso sistêmico juvenil (LESj) e comparar com indivíduos saudáveis sistemicamente. Como objetivo secundário, avaliamos o impacto do tratamento da inflamação gengival sobre a expressão das citocinas e dos níveis de anti-PPAD. Participaram do estudo 30 pacientes com LESj (idade média: 16,2 ± 1,5 anos) e 29 sem doença sistêmica (idade média 15,5 ± 2,3 anos), ambos com gengivite. Foram coletados dados reumatológicos, periodontais, sangue, fluido gengival e biofilme intrassulcular. As citocinas foram analisadas pelo multiensaio multiplex; anti-PPAD pelo ensaio de imunoabsorção enzimática (ELISA) e níveis bacterianos pelo checkerboard DNA-DNA hybridization. Para avaliar variáveis categóricas foi utilizado o teste Qui-quadrado de Pearson; para as numéricas, o teste U de Mann-Whitney e para as correlações a estatística tau-b de Kendall. No estudo longitudinal, foi utilizado o teste de McNemar para dados qualitativos, e o de Wilcoxon para dados numéricos. No estudo transversal, o grupo teste apresentou maiores níveis de profundidade de bolsa à sondagem (PBS), nível de inserção clínica (NIC), % de placa e sangramento do que o controle. Na análise do soro, G-CSF foi significativamente maior e TNF-α significativamente menor no grupo teste. Na análise do fluido gengival, IL-1ß, IL-7, IL-8, IL-13, G-CSF, IFN-γ e MCP-1 foram significativamente maiores e IL-4, IL-12(p70) e GM-CSF significativamente menores no grupo teste. Não houve diferença significativa nos níveis de anti-PPAD entre os grupos. S. constellatus, A. actinomycetencomytans, E. saburreum, V. parvula, S. intermedius, C. showae e F. nucleatum foram significantemente mais numerosas no grupo teste e A. gerencseriae e T. denticola no grupo controle. Após o tratamento da inflamação gengival, o SLEDAI, %NIC 1-2 e NIC reduziram significantemente. Já os valores de PBS e %NIC 0 aumentaram. No soro, houve diminuição significativa da IL-4 e IL-5 e aumento significativo dos níveis de anti-PPAD após o tratamento. Já no fluido gengival, houve diminuição significativa da IL-1ß, IL-10 e MCP-1 e aumento significativo da IL-4, IL-12(p70), IL-17, GM-CSF e INF-α. Sendo assim, podemos concluir que pacientes com LESj apresentaram piores condições periodontais, PBS, NIC, % de placa e sangramento do que pacientes saudáveis sistemicamente. A análise de citocinas mostrou um aumento do G-CSF e TNF-α no soro e de IL-1ß, IL-7, IL-8, IL-13, G-CSF, IFN-γ e MCP-1 no fluido gengival dos pacientes com LESj. Foram identificados anticorpos anti-PPAD nos pacientes com LESj, o que pode servir como gatilho para a quebra da tolerância imunológica. O estudo longitudinal intervencionista demonstrou que o tratamento da inflamação gengival melhorou significantemente os parâmetros %NIC 1-2 e NIC. Houve uma pequena, porém significante, piora na PBS, a qual acreditamos não ter relevância clínica. Observamos também uma melhora significante no SLEDAI e dos níveis de IL-4 e IL-5 no soro e um aumento das citocinas IL-12, IL-17 e GM-CSF no fluido gengival. Já em relação ao anticorpo anti-PPAD, observamos um aumento significativo após o tratamento da inflamação gengival.

The objectives of this study were to evaluate the expression of cytokines in serum and gingival fluid, the production of arginine-peptidyl-deiminase (anti-PPAD) and the microbiological profile of patients with juvenile systemic lupus erythematosus (jSLE) and compare with systemically healthy individuals. As a secondary objective, we evaluated the impact of treatment of gingival inflammation on cytokine expression and anti-PPAD levels. Thirty patients with jSLE (mean age: 16.2 ± 1.5 years) and 29 without systemic disease (mean age 15.5 ± 2.3 years), both with gingivitis, participated in the study. Rheumatological and periodontal data, blood, gingival fluid and intrassulcular biofilm were collected. Cytokines were analyzed by multiplex multi-assay; anti-PPAD by enzyme-linked immunosorbent assay (ELISA) and bacterial levels by checkerboard DNA-DNA hybridization. Pearson's Chi-square test was used to evaluate categorical variables; Mann-Whitney U test for numerical variables and Kendall's tau-b statistic for correlations. In longitudinal study, McNemar test was used for qualitative data, and Wilcoxon test for numerical data. In cross-sectional study, test group presented higher levels of probing depth (PD), clinical attachment level (CAL), % of plaque and bleeding than control group. In serum analysis, G-CSF were significantly higher and TNF-α significantly lower in test group. In analysis of gingival fluid, IL-1ß, IL-7, IL-8, IL-13, G-CSF, IFN-γ and MCP-1 were significantly higher and IL-4, IL-12(p70) and GM-CSF were significantly lower in test group. There was no significant difference in anti-PPAD levels between groups. S. constellatus, A. actinomycetencomytans, E. saburreum, V. parvula, S. intermedius, C. showae and F. nucleatum were significantly more numerous in test group and A. gerencseriae and T. denticola in control group. After treatment of gingival inflammation, SLEDAI, % CAL 1-2 and CAL decreased significantly. Already the values of PD and % CAL 0 increased. In serum, there was a significant decrease in IL-4 and IL-5 and a significant increase in anti-PPAD levels after treatment. In gingival fluid, there was a significant decrease in IL-1ß, IL-10 and MCP-1 and significant increase in IL-4, IL-12 (p70), IL-17, GM-CSF and INF-α. Thus, we can conclude that patients with jSLE presented worse periodontal conditions, PBS, NIC, % plaque and bleeding than systemically healthy patients. Cytokine analysis showed an increase in serum G-CSF and TNF-α and IL-1ß, IL-7, IL-8, IL-13, G-CSF, IFN-γ and MCP-1 in gingival fluid of patients with jSLE. Anti-PPAD antibodies have been identified in patients with jSLE, which may serve as a trigger for impaired immune tolerance. Longitudinal interventional study demonstrated that treatment of gingival inflammation significantly improved % CAL 1-2 and CAL parameters. There was a small, but significant worsening in PBS, which we believe has no clinical relevance. We also observed a significant improvement in SLEDAI and levels of IL-4 and IL-5 in serum and an increase in cytokines IL-12, IL-17 and GM-CSF in gingival fluid. Regarding the anti-PPAD antibody, we observed a significant increase after the treatment of gingival inflammation.

Microbiota and oxidant-antioxidant balance in systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) is a chronic infl ammatory disease of autoimmune nature, in which oxidative stress is implicated. AIM: Compare the concentrations of dietary and blood antioxidants, as well as gut microbiota, with serum malondialdehyde (MDA) and C reactive protein (CRP) in 21 subjects suffering from non-active systemic lupus erythematosus (SLE) and 21 age and gender-matched controls. METHODS: General biochemical parameters and CRP were determined by enzymatic methods: copper, zinc and selenium by inductively coupled plasma mass spectrometry (ICP-MS), MDA and total antioxidant capacity (TAC) by spectrophotometric methods, gut microbiota by metagenomic analyses and dietary intake by means of food frequency questionnaire. RESULTS: No significant differences were found in diet between lupus patients and the control group, with the exception of trans fatty acids intake, which was higher in patients. In addition, higher concentration of serum copper and lower of zinc in SLE were found. Serum copper was positively associated with CRP and also, this protein with the proportion of Lentisphaerae, ProteobacteriaandVerrucomicrobiain feces. Moreover, MDA levels displayed inverse correlations with the Cyanobacteriaand Firmicutesgroups, while Actinobacteria showed a positive association. The lupus subjects with presence of anti-SSA/Ro were related to higher levels of serum zinc. CONCLUSION: These results could be useful in the future to go deeper into the understanding of this complex disease.

Interactions of antisera to different Chlamydia and Chlamydophila species with the ribosomal protein RPS27a correlate with impaired protein synthesis in a human choroid plexus papilloma cell line.

Chlamydia trachomatis (CT) and the Chlamydophila species (CS) Chlamydophila pneumoniae (CPn), and Chlamydophila psittaci (CPs) are suggested to induce autoantibodies causative of several human autoimmune disorders like rheumatoid arthritis and systemic lupus erythematosus (SLE). The aim of the present study was therefore to identify cellular protein interaction partners with antisera to CT (α-CT) or CS (α-CS) and to identify functional consequences of such interaction in vitro. As detected with a commercial first trimester human prenatal brain multiprotein array (hEXselect, Engine, Germany), the most frequent interaction partner with both α-CT and α-CS was the ribosomal small subunit protein RPS27a. This could be confirmed by Western blot analysis with a recombinant RPS27a sample. In addition, immunocytochemistry with both antisera in the human choroid plexus papilloma cell line HIBCPP revealed a granular cytoplasmic staining, and Western blot analysis with whole-cell protein samples of HIBCPP cells revealed both antisera to label protein bands of different molecular weights and intensity. By 2D Western blot analysis and mass spectrometry, one of the protein spots interacting with α-CT could be identified as the RPS27a. Finally, two different methods for the detection of protein synthesis activity, the SUnSET technique and an HPG fluorescence assay revealed both antisera to cause reduced translational activity in HIBCPP cells. Together with previous findings of RPS27a as an autoimmune target in a mouse model of systemic lupus erythematosus (SLE), these results suggest that infections with CT and/or CS could induce SLE-associated immune modifications. However, direct evidence for a pathogenic role of these interactions for SLE demands further investigations.

Subgingival microbiota dysbiosis in systemic lupus erythematosus: association with periodontal status.

BACKGROUND: Periodontitis results from the interaction between a subgingival biofilm and host immune response. Changes in biofilm composition are thought to disrupt homeostasis between the host and subgingival bacteria resulting in periodontal damage. Chronic systemic inflammatory disorders have been shown to affect the subgingival microbiota and clinical periodontal status. However, this relationship has not been examined in subjects with systemic lupus erythematosus (SLE). The objective of our study was to investigate the influence of SLE on the subgingival microbiota and its connection with periodontal disease and SLE activity. METHODS: We evaluated 52 patients with SLE compared to 52 subjects without SLE (control group). Subjects were classified as without periodontitis and with periodontitis. Oral microbiota composition was assessed by amplifying the V4 region of 16S rRNA gene from subgingival dental plaque DNA extracts. These amplicons were examined by Illumina MiSeq sequencing. RESULTS: SLE patients exhibited higher prevalence of periodontitis which occurred at a younger age compared to subjects of the control group. More severe forms of periodontitis were found in SLE subjects that had higher bacterial loads and decreased microbial diversity. Bacterial species frequently detected in periodontal disease were observed in higher proportions in SLE patients, even in periodontal healthy sites such as Fretibacterium, Prevotella nigrescens, and Selenomonas. Changes in the oral microbiota were linked to increased local inflammation, as demonstrated by higher concentrations of IL-6, IL-17, and IL-33 in SLE patients with periodontitis. CONCLUSIONS: SLE is associated with differences in the composition of the microbiota, independently of periodontal status.

The role of macrophages in the susceptibility of Fc gamma receptor IIb deficient mice to Cryptococcus neoformans.

Dysfunctional polymorphisms of FcγRIIb, an inhibitory receptor, are associated with Systemic Lupus Erythaematosus (SLE). Cryptococcosis is an invasive fungal infection in SLE, perhaps due to the de novo immune defect. We investigated cryptococcosis in the FcγRIIb-/- mouse-lupus-model. Mortality, after intravenous C. neoformans-induced cryptococcosis, in young (8-week-old) and older (24-week-old) FcγRIIb-/- mice, was higher than in age-matched wild-types. Severe cryptococcosis in the FcγRIIb-/- mice was demonstrated by high fungal burdens in the internal organs with histological cryptococcoma-like lesions and high levels of TNF-α and IL-6, but not IL-10. Interestingly, FcγRIIb-/- macrophages demonstrated more prominent phagocytosis but did not differ in killing activity in vitro and the striking TNF-α, IL-6 and IL-10 levels, compared to wild-type cells. Indeed, in vivo macrophage depletion with liposomal clodronate attenuated the fungal burdens in FcγRIIb-/- mice, but not wild-type mice. When administered to wild-type mice, FcγRIIb-/- macrophages with phagocytosed Cryptococcus resulted in higher fungal burdens than FcγRIIb+/+ macrophages with phagocytosed Cryptococcus. These results support, at least in part, a model whereby, in FcγRIIb-/- mice, enhanced C. neoformans transmigration occurs through infected macrophages. In summary, prominent phagocytosis, with limited effective killing activity, and high pro-inflammatory cytokine production by FcγRIIb-/- macrophages were correlated with more severe cryptococcosis in FcγRIIb-/- mice.

Metagenomic Investigation of Plasma in Individuals with ME/CFS Highlights the Importance of Technical Controls to Elucidate Contamination and Batch Effects.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating disease causing indefinite fatigue. ME/CFS has long been hypothesised to have an infectious cause; however, no specific infectious agent has been identified. We used metagenomics to analyse the RNA from plasma samples from 25 individuals with ME/CFS and compare their microbial content to technical controls as well as three control groups: individuals with alternatively diagnosed chronic Lyme syndrome (N = 13), systemic lupus erythematosus (N = 11), and healthy controls (N = 25). We found that the majority of sequencing reads were removed during host subtraction, thus there was very low microbial RNA content in the plasma. The effects of sample batching and contamination during sample processing proved to outweigh the effects of study group on microbial RNA content, as the few differences in bacterial or viral RNA abundance we did observe between study groups were most likely caused by contamination and batch effects. Our results highlight the importance of including negative controls in all metagenomic analyses, since there was considerable overlap between bacterial content identified in study samples and control samples. For example, Proteobacteria, Firmicutes, Actinobacteria, and Bacteriodes were found in both study samples and plasma-free negative controls. Many of the taxonomic groups we saw in our plasma-free negative control samples have previously been associated with diseases, including ME/CFS, demonstrating how incorrect conclusions may arise if controls are not used and batch effects not accounted for.

Cryptococcal meningitis in systemic lupus erythematosus patients: pooled analysis and systematic review.

Cryptococcal meningitis is an important fungal infection among systemic lupus erythematosus patients. We conducted a pooled analysis and systematic review to describe the epidemiological and clinical profile of cryptococcal meningitis in systemic lupus erythematosus patients. From two hospitals in China and nine literature databases, cases and prevalence data were collected for pooled analysis and meta-analysis, respectively. Categorical variables of cases were compared using a χ(2)-test on the statistical program of SAS. A multiple regression analysis was performed to ascertain independent predictors significantly correlated with prognosis. Meta-analysis was conducted by the statistical program of R. The prevalence of cryptococcal meningitis in systemic lupus erythematosus patients was 0.5%. Patients were predominantly females and adults. A prednisone equivalent of more than 30 mg/day before infection was associated with higher mortality (odds ratio (OR)=9.69 (1.54, 60.73)). In all, 36.8-38.9% patients showed low lupus activity when they developed the crytococcal infection. Moreover, 38.2% of the patients were misdiagnosed. The estimated case-fatality rate was 23.6%. Our results suggest that more emphasis should be placed to further understand lupus-related cryptococcal meningitis and to develop better prophylaxis and management strategies to combat this condition.

Association between Staphylococcus aureus nasal carriage and disease phenotype in patients affected by systemic lupus erythematosus.

BACKGROUND: Staphylococcus aureus (SA) is a commensal bacterium representing one of the most important components of the skin microbiome, mostly isolated in the anterior nares. A higher rate of SA nasal colonization in patients affected by Wegener's granulomatosis and rheumatoid arthritis compared with healthy subjects (HS) has been described. No studies focusing on systemic lupus erythematosus (SLE) are available. We aimed at analyzing the prevalence of SA nasal carriers in an SLE cohort and evaluating correlation between nasal colonization and clinical, laboratory and therapeutic features. METHODS: We enrolled 84 patients with SLE (number of male/female patients 6/78; mean age 41.3 ± 12.2 years, mean disease duration 142.1 ± 103.8 months) and 154 HS blood donors. Patients with SLE underwent a physical examination and the clinical/laboratory data were collected. All the patients with SLE and the HS received a nasal swab for SA isolation and identification. RESULTS: SA nasal colonization prevalence was 21.4 % in patients with SLE and 28.6 % in HS (P not significant). We analyzed patients with SLE according to the presence (n = 18, SA-positive SLE) or the absence (n = 66, SA-negative SLE) of nasal colonization. Renal involvement was significantly more frequent in SA-positive SLE (11.6 % vs 3.0 %; P = 0.0009). Moreover, the presence of anti-dsDNA, anti-Sm, anti-SSA, anti-SSB, anti-RNP antibodies was significantly higher in SA-positive SLE (P < 0.0001, P = 0.01, P = 0.008, P = 0.03, P = 0.03, respectively). CONCLUSION: SA colonization is a relatively frequent condition in patients with SLE, with a frequency similar to HS. The presence of SA seems associated with a peculiar SLE phenotype characterized by renal manifestations and autoantibody positivity, confirming the role of the microbiome in disease phenotype.