Hematological disorders in patients with systemic lupus erythematosus

Leukemia cancer cells and immune cells derived-exosomes: Possible roles in leukemia progression and therapy

Exosomes have a significant impact on tumor survival, proliferation, metastasis, and recurrence. They also open up new therapeutic options and aid in the pathological identification and diagnosis of cancers. Exosomes have been shown in numerous studies to be essential for facilitating cell-to-cell communication. In B-cell hematological malignancies, the proteins and RNAs that are encased by circulating exosomes are thought to represent prospective sources for therapeutic drugs as well as biomarkers for diagnosis and prognosis. Additionally, exosomes can offer a "snapshot" of the tumor and the metastatic environment at any given point in time. In this review study, we concluded that leukemia-derived exosomes could be utilized as prognostic, diagnostic, and therapeutic biomarkers for individuals suffering from leukemia. Moreover, clinical studies have demonstrated that immune cells like dendritic cells create exosomes, which have the ability to activate the immune system against leukemia.

Successful treatment with belimumab for immune thrombocytopenia associated with systemic lupus erythematosus: A report of two cases

Immune thrombocytopenia (ITP) is a common complication of systemic lupus erythematosus (SLE). Glucocorticoids (GCs) and hydroxychloroquine are first-line therapy for SLE-associated ITP (SLE-ITP). SLE-ITP in most of patients is less severe and well controlled with GCs, but some of the patients are GC resistant and require additional immunosuppressants including calcineurin inhibitors, azathioprine, and rituximab. We present two cases of SLE-ITP patients treated with belimumab who were resistant to GCs and achieved remission. For severe SLE-ITP, belimumab has emerged as a novel induction therapeutic option.

Optimal Selection of IFN-α-Inducible Genes to Determine Type I Interferon Signature Improves the Diagnosis of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by the production of autoantibodies specific to self-molecules in the nucleus, cytoplasm, and cell surface. The diversity of serologic and clinical manifestations observed in SLE patients challenges the development of diagnostics and tools for monitoring disease activity. Elevated type I interferon signature (IFN- I) in SLE leads to dysregulation of innate and adaptive immune function, resulting in autoantibodies production. The most common method to determine IFN-I signature is measuring the gene expression of several IFN-α-inducible genes (IFIGs) in blood samples and calculating a score. Optimal selection of IFIGs improves the sensitivity, specificity, and accuracy of the diagnosis of SLE. We describe the mechanisms of the immunopathogenesis of IFN-I signature (IFNα production) and its clinical consequences in SLE. In addition, we explore the association between IFN-I signature, the presence of autoantibodies, disease activity, medical therapy, and ethnicity. We discuss the presence of IFN-I signature in some patients with other autoimmune diseases, including rheumatoid arthritis, systemic and multiple sclerosis, Sjogren’s syndrome, and dermatomyositis. Prospective studies are required to assess the role of IFIG and the best combination of IFIGs to monitor SLE disease activity and drug treatments.

Novel polymorphism of IFI44L associated with the susceptibility and clinical characteristics of systemic lupus erythematosus in a Chinese population

BACKGROUND

Interferon-inducible 44 like (IFI44L) is a newly discovered gene which has been reported to associate with the susceptibility of some infectious diseases, but there is no data on IFI44L SNP polymorphism associated with Systemic lupus erythematosus (SLE). In this study, we aimed to evaluate the association of IFI44L rs273259 polymorphism with the susceptibility and clinical characteristics of SLE in a Chinese population.

METHODS

576 SLE patients and 600 controls were recruited in this case-control study. Blood DNA was extracted and IFI44L rs273259 polymorphism was detected by TaqMan SNP Genotyping Assay Kit. The expression levels of IFI44L in Peripheral blood mononuclear cells were detected by RT-qPCR. The DNA methylation levels of IFI44L promoter were detected by bisulfite pyrosequencing.

RESULTS

The genotype and allele frequencies of IFI44L rs273259 in SLE patients have a significantly difference compared to healthy controls (P < 0.001). The genotype AG (vs. AA: OR = 2.849; P < 0.001) and the allele G (vs. A: OR = 1.454; P < 0.001) were associated with increased susceptibility of SLE. IFI44L rs273259 polymorphism was associated with clinical characteristics of SLE including malar rash (P < 0.001), discoid rash (P < 0.001), lupus nephritis (P < 0.001) and anti-Smith antibodies (P < 0.001). The expression levels of IFI44L were most significantly increased in genotype AG than genotype AA and GG (P < 0.01). The DNA methylation levels of IFI44L promoter were most significantly decreased in genotype AG than genotype AA and GG (P < 0.01).

CONCLUSIONS

Our results indicate novel polymorphism of IFI44L rs273259 was associated with the susceptibility and clinical characteristics of SLE in the Chinese population.

Catastrophic antiphospholipid syndrome in lupus-associated immune thrombocytopenia treated with eltrombopag A case series and literature review

BACKGROUND

Eltrombopag, a thrombopoietin receptor (TPO-R) agonist, is considered a second-line treatment for patients with refractory immune thrombocytopenia (ITP). Systemic lupus erythematosus (SLE) is frequently associated with ITP. In some cases, thrombocytopenia in SLE patients is attributed to concurrent antiphospholipid antibodies (APLA). Currently, data regarding treatment with TPO-R agonists for ITP in SLE or APLA patients are limited. The incidence of SLE flare or antiphospholipid syndrome while on TPO-R agonists has not been well-studied.

CASES

We report 2 cases of female patients with SLE and concurrent triple positive APLA, without thrombotic events in their medical history, in our rheumatology clinic, who were treated for refractory ITP with eltrombopag. Both developed catastrophic antiphospholipid syndrome a few weeks after beginning treatment with eltrombopag. They were admitted to the intensive care unit and treated with solumedrol, plasmapheresis, anticoagulation and rituximab.

CONCLUSIONS

We describe a severe possible side-effect of eltrombopag as a trigger of catastrophic antiphospholipid syndrome, a rare initial manifestation of antiphospholipid syndrome, in SLE patients with APLA. We suggest that APLA should be tested before initiating eltrombopag in patients with SLE-associated ITP. The safety of this treatment should be considered in these cases.

Association of the Gelatinase B/Metalloproteinase 9 (MMP-9) Gene Haplotype in Systemic Lupus Erythematosus (SLE) in the Pediatric Egyptian Population

Permanent systemic inflammation is a defining feature of systemic lupus erythematosus (SLE), which affects multiple organs. Gelatinase B/matrix metalloproteinase-9 (MMP-9) is an essential protease investigated in inflammation that has been linked to SLE. The study’s objective was to investigate the relationship between the rs3918249 T/C and rs17576 A/G SNPs in the MMP-9 gene with SLE. The study was conducted with 100 SLE cases and 100 age/sex-matched healthy individuals. TaqManTM SNP was used for genotyping by real time PCR on the Artus Rotor-Gene Qiagen equipment. Haplotypes (TG: OR = 0.226, 95% CI = 0.119−0.429) and (CA: OR = 0.36, 95% CI = 0.2206−0.631), both with a p-value < 0.001 were substantially linked to a lower incidence of SLE. Conversely, the risk of SLE was not associated with the individual SNPs studied. The haplotype analysis was more significant than the SNP analysis and may correlate with the decreased risk of SLE in children and adolescents in Egypt.

A Prospective Follow-Up Study on the Disease Course and Predictors of Poor Outcomes in a Random Population-Based Cohort of Newly Diagnosed Lupus Patients

Background and objective

Systemic lupus erythematosus (SLE) is one of the most devastating systemic autoimmune connective tissue diseases. There is a paucity of prospective data on Pakistani SLE patients, and in this prospective study, we aimed to investigate the disease course, clinical outcomes, and the predictors of poor outcomes in a random population-based cohort of newly diagnosed SLE patients (diagnosed within the last one year).

Methods

This was a prospective observational study carried out in the rheumatology department of the Fatima Memorial Hospital, Lahore. Lupus patients are regularly reviewed in our dedicated lupus clinic every one to three months. For the purpose of this study, a focus group of newly diagnosed patients (diagnosed within the last one year) attending our lupus clinic was identified and prospectively followed up for 12 months. A wide range of demographical and clinical parameters was recorded. The association of clinical variables with the progressive disease was determined using univariate and multivariate logistic regressions.

Results

Prospective data of 89 newly diagnosed SLE patients regularly attending our dedicated lupus clinic were reviewed. During the study period, (January 2021 through January 2022), these patients had multiple visits overall - median: five, minimum: three, and maximum: nine visits [interquartile range (IQR) 4-7]. All 89 patients had completed one year of follow-up. Of note, 46% of the cohort was noted to have an ongoing active disease during the majority of visits in the study period. On multiple logistic regression analysis, there was a significant association between ongoing active disease ("progressors") and low education status [odds ratio (OR): 2.81, 95% confidence interval (CI): 1.01-7.76, p=0.046], stress at home (OR: 5.8, 95% CI: 2.13-15.8, p=0.001), and hematologic manifestations (OR: 3.0, 95% CI: 1.08-8.32, p=0.03).

Conclusions

Almost half of our cohort of lupus patients demonstrated active disease manifestations throughout the one-year prospective follow-up, and these were found to be associated with low education status, stress at home, and hematological manifestations.

Therapeutic approaches targeting CD95L/CD95 signaling in cancer and autoimmune diseases

Cell death plays a pivotal role in the maintenance of tissue homeostasis. Key players in the controlled induction of cell death are the Death Receptors (DR). CD95 is a prototypic DR activated by its cognate ligand CD95L triggering programmed cell death. As a consequence, alterations in the CD95/CD95L pathway have been involved in several disease conditions ranging from autoimmune diseases to inflammation and cancer. CD95L-induced cell death has multiple roles in the immune response since it constitutes one of the mechanisms by which cytotoxic lymphocytes kill their targets, but it is also involved in the process of turning off the immune response. Furthermore, beyond the canonical pro-death signals, CD95L, which can be membrane-bound or soluble, also induces non-apoptotic signaling that contributes to its tumor-promoting and pro-inflammatory roles. The intent of this review is to describe the role of CD95/CD95L in the pathophysiology of cancers, autoimmune diseases and chronic inflammation and to discuss recently patented and emerging therapeutic strategies that exploit/block the CD95/CD95L system in these diseases.

Annexin A1 and its receptor gene polymorphisms in systemic lupus erythematosus in the Tunisian population

BACKGROUND

An association between ANXA1, FPR1 and FPR2 gene polymorphisms and the patho-physiology of many human diseases was suggested by numerous studies.

OBJECTIVE

Our study aimed to evaluate association between common polymorphisms in the 9q21.13 and 19q13.41 and susceptibility to systemic lupus erythematosus (SLE) in the Tunisian population.

MATERIALS

We performed a case-control study on 107 Tunisian SLE patients and 122 healthy controls to explore 9 polymorphisms of the three studied genes: rs2811226 and rs3739959 (ANXA1), rs5030880, rs1042229, rs1461765570, rs17849971, rs867228 (FPR1), rs17694990 and rs11666254 (FPR2).

RESULTS

Four polymorphisms were found to be linked with SLE susceptibility: rs3739959-ANXA1 > G and GG (p = 0.021, OR = 1.73 and p = 0.014, OR = 2.06 respectively), rs867228-FPR1 > TT (p = 0.014, OR = 4.59), rs11666254-FPR2 > GG (p = 0.019, OR = 8.34) and rs17694990-FPR2 > T (p = 0.05, OR = 1.506). In homogenous groups of SLE patients depending on clinical manifestations and serological results, previous associations were confirmed with a panoply of manifestations of lupus including lupus nephritis, malar rash, mouth ulceration and hypocomplementia.

CONCLUSION

Our study showed an association between ANXA1 > rs3739959, FPR1 > rs867228, FPR2 > rs11666254, FPR2 > rs17694990 and SLE susceptibility. Our results also showed a strong association between the two ANXA1 studied SNPs and LN which allowed us to suggest these two SNPs as biomarkers of LN development in SLE. Further research is needed to understand by which mechanism the gene variants affect susceptibility to SLE. Key Points • Lupus erythematosus is an autoimmune disease in which a panoply of factors are implicated • Annexin A1 interaction with its receptors are suggested as a target in therapy of a panoply of human disease in particular cancers • The present results highlighted the implication of Annexin A1 and its receptors gene polymorphisms in the physiopathology of lupus, in particular in the involvement of renal and cutaneous lesions.

Sensitive and real-time detection of IgG using interferometric reflecting imaging sensor system

Considering the limitations of well-known traditional detection techniques, innovative research studies have focused on the development of new sensors to offer label-free, highly sensitive, real-time, low-cost, and rapid detection for biomolecular interactions. In this study, we demonstrate immunoglobulin G (IgG) detection in aqueous solutions by using real-time and label-free kinetic measurements of the Interferometric Reflectance Imaging Sensor (IRIS) system. By performing kinetic characterization experiments, the sensor's performance is comprehensively evaluated and a high correlation coefficient value (>0.94) is obtained in the IgG concentration range of 1-50 μg/mL with a low detection limit (0.25 μg/mL or 1.67 nM). Moreover, the highly sensitive imaging system ensures accurate quantification and reliable validation of recorded binding events, offering new perspectives in terms of direct biomarker detection for clinical applications.

Association of Hydroxychloroquine use and Hemolytic Anemia in Patients With Low Levels of Glucose-6-Phosphate Dehydrogenase

BACKGROUND

Glucose-6-phosphate dehydrogenase deficiency (G6PD) is linked to hemolytic anemia with certain medications and is the most common enzyme deficiency worldwide. Although the American College of Rheumatology does not recommend routine testing for G6PD prior to initiation of hydroxychloroquine (HCQ), the package insert for HCQ does recommend careful use in patients with G6PD deficiency.

METHODS

We identified eligible subjects seen at our tertiary care, urban medical center between 1997 and 2018. Case records were analyzed for G6PD deficiency, HCQ use, length of exposure to HCQ, demographic characteristics, and laboratory evidence of hemolysis.

RESULTS

We found 5264 patients who were prescribed HCQ, of which 49.5% (2605 patients) were screened for G6PD deficiency. Of the screened patients, 36 were found to be G6PD-deficient. Of the G6PD-deficient patients, 18 were exposed to HCQ. No evidence of hemolysis was found in these exposed patients.

CONCLUSIONS

Despite more than 500 months of cumulative exposure time to HCQ, there were no cases of hemolysis. These findings are in line with recently published data and suggest that this interaction is not associated with clinically significant hemolysis in our population of mainly African American and Hispanic patients. Limitations to our study are potential bias due to case review design and lack of prior assessment of episodes of hemolysis before HCQ exposure. A high proportion of our patients were Hispanic, suggesting no increase of adverse events in this subgroup. A larger longitudinal trial would be needed to definitively answer the question of the safety of HCQ in G6PD-deficient patients.

From Telemedicine to the ICU-Fever and Rash in a 9-Year-Old Girl

A 9-year-old girl presented to her primary care pediatrician via telemedicine during the initial months of the coronavirus disease 2019 pandemic because of 4 days of warmth perceived by her mother, decreased energy, and a new rash on her upper extremities. After 10 additional days of documented fever >38°C, worsening fatigue, and 1 day of nausea, vomiting, and diarrhea, she was allowed to schedule an in-person visit with her pediatrician after testing negative for severe acute respiratory syndrome coronavirus 2. She appeared ill on arrival to clinic, and her pediatrician recommended evaluation in an emergency department. Her initial laboratory testing revealed nonspecific elevation in several inflammatory markers and leukopenia, and she responded well to intravenous hydration. Over the next 2 weeks, her fever persisted, constitutional symptoms worsened, and she developed progressively painful cervical lymphadenopathy and pancytopenia. She was evaluated in clinic by several specialists and eventually was urged to present to the emergency department again, at which time she was admitted to the PICU. After consulting additional specialists and waiting for laboratory results, the team reached a definitive diagnosis and initiated therapy; however, she experienced rapid clinical decline shortly thereafter. The specialists who assisted with identification of the underlying etiology of her symptoms were able to work together to manage the subsequent complications.

Pregnancy termination in patients with rheumatic diseases

Rheumatic diseases affect women during their reproductive years. Many women with rheumatic diseases become pregnant; some undergo pregnancy termination. However, there are no official guidelines on pregnancy termination in patients with rheumatic diseases. This paper provides an overview of considerations that healthcare professionals must take into account. We highlight areas that require further studies and the importance of pregnancy planning and contraception counseling. Patients with rheumatic diseases need to be informed of adverse maternal and fetal outcomes of pregnancy to make informed reproductive decisions and reduce the need for pregnancy terminations. This article is protected by copyright. All rights reserved.

Plasma interleukin-22 level, variants in interleukin-22 gene polymorphism, and the severity of systemic lupus erythematosus among Egyptian pediatric and adolescents

OBJECTIVES

Our purpose was to investigate, for the first time, genotypes and alleles distribution of two single nucleotide polymorphisms (SNPs) of interleukin 22 (IL-22) (rs1012356 and rs2227485) in Egyptian pediatric and adolescents with systemic lupus erythematosus (SLE) and to evaluate the plasma IL-22 levels and their association with gene polymorphism and SLE risk and severity.

METHODS

The TaqMan™ SNP genotyping assay on a real-time polymerase chain reaction (PCR) system was employed to evaluate the polymorphism's genotypes. Plasma IL-22 levels were determined by using an enzyme-linked immunoabsorbent assay (ELISA).

RESULTS

The frequencies and genotypes of rs2227485 and rs1012356 in IL-22 between SLE patients and controls also haplotypes formed by the same SNPs revealed no statistically significant difference (p > 0.05). Otherwise, logistic regression analysis revealed that patients carrying rs1012356 "TA + AA" genotype had increased risk for prediction of SLE activity (OR = 1.610, 95% CI = 1.339-2.760, p = 0.034) by lowering plasma IL-22 level.

CONCLUSIONS

Among Egyptian pediatric and adolescents, we confirm a combined model "TA + AA" in rs1012356 (A/T) of IL-22 in regression analysis, as an independent predictor for SLE activity by lowering IL-22 plasma levels. Despite neither SNP rs2227485 A/G in IL-22 gene nor haplotypes formed by the same two SNPs (rs2227485 A/G and rs1012356 A/T) were significantly associated with the clinical and/or laboratory manifestations of SLE.

Hematological involvement in pediatric systemic lupus erythematosus: A multi-center study

Introduction: Systemic lupus erythematosus (SLE) may present with features of several systems, including hematological manifestations. In this study, we aimed to evaluate the characteristics of hematological involvement and assess possible associations and correlations in pediatric SLE patients. Method: This is a retrospective multi-center study. The medical records of pediatric SLE patients followed between January 2000 and June 2020 were analyzed. All children fulfilled the criteria of the Systemic Lupus International Collaborating Clinics. Results: The study included 215 children with SLE, 118 of whom had hematological manifestations. Concomitant renal involvement and low C3 levels were significantly more frequent in patients with hematological involvement (p = 0.04, p = 0.008, respectively). Also, anti-cardiolipin, anti-beta-2-glycoprotein I (anti-β2 GP1), and anti-Sm antibody positivity, and the presence of lupus anticoagulant were more common in the group with hematological findings (p = 0.001 for anti-cardiolipin antibody positivity and p < 0.001 for the positivity of anti-β2 GP1 antibody, anti-Sm antibody, and lupus anticoagulant). The most common hematologic abnormality was anemia (n = 88, 74.5%), with autoimmune hemolytic anemia constituting the majority (n = 40). Corticosteroids followed by IVIG were the mainstay of treatment. In patients resistant to corticosteroid and IVIG treatments, the most preferred drug was rituximab. Low levels of C3, high SLEDAI score, high incidence of renal involvement, and positive antiphospholipid antibodies were associated with hematological involvement in the univariate analysis. The presence of antiphospholipid antibodies and high SLEDAI score were independently associated with hematological involvement in multivariate analysis (OR: 4.021; 95% CI: 2.041-7.921; p < 0.001 and OR: 1.136; 95% CI: 1.065-1.212; p < 0.001). Conclusion: Hematological abnormalities are frequently encountered in pediatric SLE. Positive antiphospholipid antibodies and high SLEDAI scores were associated with hematological involvement.

Genetic Polymorphisms in Genes Involved in the Type I Interferon System (IFIH1/MDA-5, TNFAIP3/A20, and STAT4): Association with SLE Risk in Egyptian Children and Adolescents

Purpose

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune inflammatory disease that is influenced by both genetic and environmental factors and associated with dysregulation of type I interferon (INF) response. This study aimed to investigate the effects of single nucleotide polymorphisms (SNPs) of the IFIH1, TNFAIP3, and STAT4 genes in the type I INF system on SLE risk in Egyptian children and adolescents.

Patients and Methods

We recruited 94 SLE individuals and 94 healthy subjects. SNPs of IFIH1 rs3747517 C/T, TNFAIP3 rs610604 G/T, and STAT4 rs7574865 G/T were evaluated using TaqMan™ SNP genotyping assay.

Results

Individuals with the TT, CT+TT genotypes, and T allele of rs3747517 in the IFIH1 gene were protective for SLE patients (OR = 0.429, 95% CI = 0.191-0.962, P = 0.040), (OR = 0.685, 95% CI = 0.477-0.984, P = 0.041), and (OR = 0.705, 95% CI = 0.527-0.944, P = 0.019), respectively. Also, individuals with the TT, GT+TT genotypes, and T allele of rs7574865 in the STAT4 gene were associated with SLE risk (OR = 3.945, 95% CI = 1.303-11.947, P = 0.015), (OR = 1.536, 95% CI = 1.058-2.231, P = 0.024), and (OR = 1.522, 95% CI = 1.113-2.082, P = 0.009), respectively. In the case of TNFAIP3 rs610604, no significant association of genotypes or alleles with SLE were detected, while the three SNPs did not show any significant association with the SLE clinical or laboratory features.

Conclusion

Our findings indicated that rs3747517 in IFIH1 was protective for SLE in Egyptian children and adolescents. Moreover, rs7574865 in STAT4 not rs610604 in TNFAIP3 was associated with SLE risk.

AUTOIMMUNE MYELOFIBROSIS ASSOCIATED WITH LUPUS: UNUSUAL OR UNDETECTED?

AUTOIMMUNE MYELOFIBROSIS ASSOCIATED WITH LUPUS: UNUSUAL OR UNDETECTED?

Long-term immunosuppression and multiple transplants predispose systemic lupus erythematosus patients with cytopenias to hematologic malignancies

Cytopenias in systemic lupus erythematosus (SLE) require clinical and laboratory workup and bone marrow (BM) examination to determine the cause and for appropriate patient management. Common causes include an increase in SLE activity, immune-mediated hemolysis, iron deficiency, antiphospholipid antibody syndrome, infection, or the effect of medications. We retrospectively evaluated the clinical and laboratory findings of patients with SLE and cytopenias who had undergone BM studies to determine the indicators of malignancy.We retrospectively reviewed medical records of patients with SLE who presented with cytopenias for their disease course, medications, laboratory parameters and documented the spectrum of morphological changes in BM including CD34 expression.Twenty patients with SLE had undergone BM biopsy for evaluation of cytopenias. 14/20 (70%) of the patients had reactive BM, and the rest had hematologic malignancies involving the BM. Of these 14 patients, 8 had hypocellular marrow with loss of precursor cells (low CD34), 4 had left shift in myeloid lineage, 3 had serous atrophy, and 1had multilineage dysplasia. The 6 patients with hematologic malignancies included 2 with diffuse large B cell lymphoma, and one each of natural killer/T cell lymphoma, post-transplant lymphoproliferative disorder, Hodgkin lymphoma, and myelodysplastic syndrome evolving to acute myelogenous leukemia. The presence of autoantibodies, SLE activity, and lupus nephritis were comparable in patients with and without neoplasia. However, the duration of the use of multiple immunosuppressants, years since renal transplant (22 vs 10), multiple transplants, and the presence of other autoimmune diseases were greater in those with neoplasia. Two of the 14 patients with non-neoplastic BM and 1 with the neoplastic BM had nonhematological malignancy.Clinical and laboratory findings, the number of transplants, and the use of immunosuppressive agents can guide physicians to identify patients with a higher risk of developing hematologic malignancy. BM findings of cytopenia in SLE are often due to increased disease activity causing global cell death and dysmaturation. SLE patients presenting with cytopenias, with a history of long-term exposure to immunosuppressive drugs, should be regularly screened for hematologic and nonhematologic malignancies.

Exercise alleviates symptoms of CNS lupus

Systemic lupus erythematosus (lupus) is a global health problem where 20-80% patients display cognitive problems and central nervous system (CNS) dysfunction. Early diagnosis and treatment of lupus remains a clinical challenge. Exercise improves experimental lupus nephritis. However, the effects of exercise in CNS lupus remains unknown. This study investigates the effects of controlled exercise (CE) that consisted of treadmill walking (5 m/min for 10 min everyday) on experimental CNS lupus using the well-established mouse model, MRL/lpr mice. The MRL/lpr mice were subjected to CE from 8 weeks (preclinical) to 16 weeks (disease). Multiplex gene expression analysis revealed significant upregulation of genes involved in neurite growth, proliferation and synaptic plasticity, and a decrease in inflammatory genes including complement proteins, NFkB, chemokines and cytokines in exercised mice compared to the unmanipulated, age-matched controls. The loss of blood-brain barrier integrity, astrogliosis and edema seen in MRL/lpr mice were reduced with exercise. Exercised mice performed better in behavioral assessments such as open field, nesting, and tail suspension test. For the first time our results show that a supervised, well-regulated and controlled exercise regimen alleviates CNS lupus and could potentially serve as an intervention strategy to improve the quality of life. Exercise could also serve as an adjunct therapy for lupus and other neuroinflammatory diseases, thereby reducing the need for the current therapies with toxic side effects. The validity of the findings and a safe exercise regimen needs to be established by additional studies in patients.

Pyoderma gangrenosum and cobalamin deficiency in systemic lupus erythematosus: a rare but non fortuitous association

BACKGROUND

Pyoderma gangrenosum (PG) is an uncommon, idiopathic, ulcerative neutrophilic dermatosis. In many cases, PG is associated with a wide variety of different disorders but SLE in association with PG is relatively uncommon. In this article we present the case of a middle aged patient with PG as the initial clinical presentation of SLE. We also provide a brief review of cobalamin deficiency which occurred in our patient and evidence-based management options.

CASE PRESENTATION

A 35 years old man presented with a 5 month history of debilitating painful lower limb and scrotal ulcers. This was associated with polyarthralgia and morning stiffness involving both hands. He also complained of swallowing difficulties. He had unintentional weight loss of 10 kg and fatigue. Physical examination revealed alopecia, multiple cervical lymphadenopathies, bilateral parotid gland enlargement and atrophic glossitis. There was Raynaud's phenomenon noted over both hands and generalised hyper-pigmented fragile skin. Laboratory results disclosed anaemia, leukopenia, hyponatraemia and hypocortisolism. Detailed anaemic workup revealed low serum ferritin and cobalamin level. The autoimmune screen showed positive ANA, anti SmD1, anti SS-A/Ro 52, anti SSA/Ro 60, anti U1-snRNP with low complement levels. Upper gastrointestinal endoscopy with biopsies confirmed atrophic gastritis and duodenitis. Intrinsic factor antibodies and anti-tissue transglutaminase IgA were all negative. Punch biopsies of the leg ulcer showed neutrophilic dermatosis consistent with pyoderma gangrenosum. Based on the clinical findings and positive immunologic studies, he was diagnosed as systemic lupus erythematosus. His general condition improved substantially with commencement of corticosteroids, immunosuppressants and vitamin supplements.

CONCLUSIONS

We report a case of PG as the first manifestation of SLE which was treated successfully with immunosuppressants and vitamin supplements. Our report highlighted the need to consider connective tissue diseases such as SLE in a patient presenting with PG in order for appropriate treatment to be instituted thereby achieving a good outcome.

Single-nucleotide polymorphisms (SNPs) of antioxidant enzymes SOD2 and GSTP1 genes and SLE risk and severity in an Egyptian pediatric population

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease associated with increased oxidative stress that participates in immune dysregulation, and injury resulting in loss of immune tolerance and increased auto-antibody production. This study was designed to investigate the effects of genetic polymorphisms of the antioxidant enzymes genes that code for SOD2 (rs2758332) and GSTP1 (rs1695) on SLE risk and severity in Egyptian children and adolescents cohort from Delta region.

METHODS

The frequencies of these genes polymorphic variants were compared between 100 SLE children and adolescents and 100 healthy control subjects. Single-nucleotide polymorphisms (SNPs) of the two antioxidants were determined using TaqMan SNP genotyping assay.

RESULTS

Individuals with the TT and CT genotypes of rs2758332 in the SOD2 gene were of significant risk for SLE patients (OR = 1.831, 95% CI = 1.082-3.101, P = 0.024) and (OR = 1.864, 95% CI = 1.136-3.059, P = 0.014), respectively. Cases who have combined CT + TT genotype were of significant higher risk of SLE (OR = 1.851, 95% CI = 1.156 - 2.962, P = 0.010). While, they did not show any significant association between SOD2 genotypes or alleles with SLE clinical features. In case of the SNP rs1695 in the GSTP1 gene, no significant associations of genotypes or alleles with SLE risk or with SLE clinical features were detected.

CONCLUSIONS

This study among Egyptian children and adolescents showed a strong association of the SOD2 rs2758332 not GSTP1 rs1695 polymorphism with the risk of SLE disease.

Platelet Dysfunction Diseases and Conditions: Clinical Implications and Considerations

INTRODUCTION

Platelet diseases and dysfunction are taught early in medical school to all future physicians. Understanding of the coagulation cascade and hemostatic mechanisms has allowed for targeted pharmacological therapies that have been significantly impactful in clinical practice. Platelets are an early participant in hemostasis physiologically and under pathophysiological states.

METHODS

A review of literature involving platelet disfunction.

RESULTS

Various presentations of platelet diseases and dysfunction challenge clinicians and require a firm understanding of normal platelet function, drugs that mediate or modulate platelet effectiveness, and nonpharmacologic etiologies of platelet diseases and dysfunction with corresponding best practice treatment approaches.

CONCLUSION

This review summarizes normal and abnormal states associated with platelets and treatment strategies.

Treatment of primary and secondary immune thrombocytopenia

PURPOSE OF REVIEW

Medical therapies for the treatment of immune thrombocytopenia (ITP) complicating SLE are increasingly being investigated as alternatives to splenectomy and IVIG. The purpose of this review is to highlight the therapies that are utilized in the treatment of primary ITP and ITP secondary to lupus.

RECENT FINDINGS

Corticosteroids are still the standard initial treatment of ITP, with the addition of IVIG when a rapid response is needed. There are few studies dedicated to assessing the efficacy of disease-modifying antirheumatic (DMARD), biologic, and nonimmunosuppressive agents as treatment for lupus thrombocytopenia/lupus ITP. Rituximab and thrombopoeitin mimetics have been the most extensively studied therapies for primary ITP in recent years. Results of trials show adequate initial responses; however, the duration of therapy and sustainability of responses are variable. Splenectomy is less often utilized.

SUMMARY

Although corticosteroids, intravenous immunoglobulin and splenectomy have proven to be effective measures to treat immune thrombocytopenia, newer studies have demonstrated positive outcomes of immunosuppressives and thrombopoeitin mimetics. In most cases, the reported duration of therapy was not prolonged. More studies are needed to fully assess the effect of medical therapy in lupus ITP and to determine how long to continue maintenance therapy.

The presence of IFL3/4 rs12979860 C allele influences the in vitro IP-10 production by mononuclear cells from patients with systemic lupus erythematosus

OBJECTIVE

To explore whether the IFNL3/4 rs12979860 genotype may influence serum levels or production of interferon-inducible protein-10 (IP-10) by peripheral blood mononuclear cells from patients with systemic lupus erythematosus (SLE).

METHODS

Sixty-six patients with SLE and 22 healthy blood donors (controls) were included. The IFNL3/4 rs12979860 polymorphism was genotyped by real-time polymerase chain reaction. IP-10 levels in sera supernatants of IFNα stimulated peripheral blood mononuclear cells were measured by enzime-linked immunosorbent assay.

RESULTS

Allelic frequencies were CC (29%), CT (52%) and TT (20%) in SLE, and CC (32%), CT (41%) and TT (27%) in healthy controls. Median serum IP-10 levels were higher in SLE patients than in controls (190.8 versus 118.1 pg/ml; p < 0.001), particularly in those with high disease activity (278.5 versus 177.2 pg/ml; p = 0.037). However, serum IP-10 levels were not influenced by IFNL3/4 genotypes. Higher IP-10 production by peripheral blood mononuclear cells was found in both SLE patients (median 519.3 versus 207.6 pg/ml; p = 0.012) and controls (median 454.0 versus 201.7 pg/ml; p = 0.034) carrying the IFNL3/4 C allele compared with carriers of the T allele.

CONCLUSIONS

Although IFNL3/4 rs12979860 allele C does not appear to influence serum IP-10 levels in SLE, it plays an important role in the production of IP-10 by peripheral blood mononuclear cells after IFNα stimulation.

The αC helix of TIRAP holds therapeutic potential in TLR-mediated autoimmune diseases

Despite being crucial for combating microbes, paradoxical Toll-like receptors (TLRs) signaling have been associated with the aggravation of multiple immune disorders such as systemic lupus erythematosus, psoriasis, rheumatoid arthritis, and nonalcoholic steatohepatitis. The stoichiometry and precise arrangement of the interaction of adapters (via their Toll/interleukin-1 receptor [TIR] domains) are indispensable for the activation of TLRs and of downstream signaling cascades. Among adapters, plasma membrane-anchored MyD88 adaptor-like (MAL) has the potential for BB-loop-mediated self-oligomerization and interacts with other TIR domain-containing adaptors through αC and αD helices. Here, we used information on the MAL-αC interface to exploit its pharmacophores and to design a decoy peptide (MIP2) with broad-range TLR-inhibitory abilities. MIP2 abrogated MyD88- and TRIF-dependent lipopolysaccharide (LPS)-induced TLR4 signaling in murine and human cell lines and manifested a therapeutic potential in models of psoriasis, systemic lupus erythematosus, nonalcoholic steatohepatitis, and sepsis. Levels of hallmark serological and histological biomarkers were significantly restored and the disease symptoms were substantially ameliorated by MIP2 treatment of the animals. Collectively, our biophysical, in vitro, and in vivo findings suggest that MIP2 has broad specificity for TLRs and may be effective in modulating autoimmune complications caused by microbial or environmental factors.

Does the Epstein-Barr Virus Play a Role in the Pathogenesis of Graves' Disease?

Graves’ disease (GD) it the most common chronic organ-specific thyroid disorder without a fully recognized etiology. The pathogenesis of the disease accounts for an interaction between genetic, environmental, and immunological factors. The most important environmental factors include viral and bacterial infections. The Epstein-Barr virus (EBV) is one of the most common latent human viruses. Literature has suggested its role in the development of certain allergic and autoimmune diseases. EBV also exhibits oncogenic properties. The aim of the study was to analyze and compare the presence of EBV DNA in peripheral blood mononuclear cells (PBMCs) in patients with newly recognized GD and to find a correlation between EBV infection and the clinical picture of GD. The study included 39 untreated patients with newly diagnosed GD and a control group of 20 healthy volunteers who were gender and age matched. EBV DNA was detected with reverse transcription polymerase chain reaction (RT PCR) assay. The studies showed a significantly higher incidence of EBV copies in PBMCs among GD patients compared to the control group. Whereas, no significant correlations were found between the incidence of EBV copies and the evaluated clinical parameters. Our results suggest a probable role of EBV in GD development. EBV infection does not affect the clinical picture of Graves’ disease.

Effect of Age on Leukopenia Following Renal Transplantation at a Single Center

Introduction:

Leukopenia in renal transplant recipients occurs commonly within the first year following transplantation; however, literature on the effects of age on leukopenia is scarce.

Design:

A single-center, retrospective review was conducted on 141 recipients transplanted from January 2011 to December 2015. Transplant recipients were characterized by age <60 years (n = 94) or age 60 years and older (n = 47) for analysis.

Results:

A greater incidence of leukopenia was seen in the older cohort compared to the younger cohort (64% vs 55%). Of those patients who developed leukopenia, the older cohort (n = 30) had a higher incidence of hospitalization for leukopenia (30% vs 23%) but a lower incidence of hospitalization for infection (20% vs 25%) compared to the younger cohort (n = 52). Additionally, one month following mycophenolate mofetil (MMF) discontinuation, the older cohort had reduced recovery of their white blood cell count (+263.8% vs +272.5%) and experienced less recurrent leukopenic episodes (50% vs 67%) and rejection episodes (0% vs 22%) compared to the younger cohort, alluding to the need for less immunosuppression.

Conclusions:

Age at transplantation was not associated with the development of leukopenia; however, older patients had a higher incidence of leukopenia and hospitalization for leukopenia. Dose reduction or discontinuation of MMF should be considered in older kidney transplant recipients who develop leukopenia.

Immunological and Clinical Characteristics of Systemic Lupus Erythematosus: A Series from Morocco

Systemic Lupus Erythematosus (SLE) is a complex autoimmune disease with a high female predominance. To date, studies about SLE in Morocco are few. This retrospective study describes the clinical and immunological features in a series of 50 SLE Moroccan patients in University Hospital Center of Rabat, Morocco, between December 2011 and December 2013. All patients were screened for antinuclear antibodies (ANA) and anti-DNA antibodies by indirect immunofluorescence, followed by identification of anti-extractable nuclear antigen antibodies by ELISA. The female to male ratio was 6.1:1. Mean age was 31.72 years. The main clinical manifestations were arthritis (82%), mucocutaneous manifestations (80%), renal manifestations (50%), and hematological features (46%). Of the mucocutaneous features, the highest frequencies were observed in the malar rash (68%) and photosensitivity (60%). Of the hematological features, lymphopenia was most frequently observed in 30% of patients, followed by hemolytic anemia in 16% and leucopenia and thrombocytopenia in 8%. Central nervous system was involved in 10%. ANA were found in 88%, anti-DNA antibodies in 56%, and anti-Sm antibodies in 50%. Anti-SSA, anti-SSB, anti-Sm/RNP, and anti-Scl70 antibodies were detected in 38%, 10%, 48%, and 8%, respectively. Our data show that, in our patients, the main clinical and immunological features of SLE remain comparable to patients from other Arab countries.

The Role of Hydroxychloroquine as a Steroid-sparing Agent in the Treatment of Immune Thrombocytopenia: A Review of the Literature

Immune Thrombocytopenia (ITP) is an autoimmune disease in which platelet destruction causes thrombocytopenia. Due to the known steroid toxicities, alternative agents have been evaluated for the treatment of these patients. We aimed to review the literature and find evidences regarding the potential benefits of hydroxychloroquine (HCQ) as a steroid-sparing agent in the treatment of ITP. We searched English language articles within Web of Science, PubMed, and Scopus. Cohorts, clinical trials, case reports, conference papers, and letters were included. We excluded papers which either focused on administration of HCQ for non-ITP conditions or studies on other treatment modalities for ITP. In total, 54 ITP cases with either primary or systemic lupus erythematosus (SLE)-associated ITP were included in four studies (SLE-associated ITP; n = 23). All patients have received corticosteroids previously and >90% received other agents with HCQ concomitantly. Overall response was achieved in more than 60% of patients. Sustained response in 18 (33.3%) patients was associated with no treatment or HCQ alone. One of the studies reported a significantly better response in patients with definite SLE compared to those with positive antinuclear antibody and no definite SLE. Similarly, another study found a nonsignificant trend toward better long-term response in patients with definite SLE compared to incomplete SLE. The included articles reported the efficacy of the HCQ with acceptable safety. Available data regarding the use of HCQ for this indication are spare and more studies are needed in ITP with different severity. It seems that HCQ can be considered as an option in the treatment of SLE-associated ITP, and although promising, currently, the place of HCQ in the treatment of ITP continues to evolve.

Consequences of dysregulated complement regulators on red blood cells

The complement system represents the first line of defense that is involved in the clearance of pathogens, dying cells and immune complexes via opsonization, induction of an inflammatory response and the formation of a lytic pore. Red blood cells (RBCs) are very important for the delivery of oxygen to tissues and are continuously in contact with complement proteins in the blood plasma. To prevent complement activation on RBCs, various complement regulatory proteins can be found in plasma and on the cell membrane. RBCs are special cells without a nucleus and having a slightly different make-up of complement regulators than nucleated cells, as membrane cofactor protein (MCP) is not expressed and complement receptor 1 (CR1) is highly expressed. Decreased expression and/or function of complement regulatory proteins may result in unwanted complement activation and accelerated removal of RBCs. This review describes complement regulation on RBCs and the consequences when this regulation is out of balance.

Zytopenien

Hematological alterations can often be observed during rheumatic diseases. The effects can be clinically severe, ranging from anemia of different grades of severity, through increased risk of hemorrhage due to thrombocytopenia up to severe infections as a result of high-grade leukocytopenia. The clinical sequelae for patients are predominantly determined by the extent of cytopenia. The underlying disease itself can initially be considered as the cause. Examples are anemia as a result of chronic inflammation, antibody-mediated thrombocytopenia as in systemic lupus erythematosus (SLE) or granulocytopenia within the framework of Felty's syndrome. Immunosuppressive treatment also often leads to alterations in the blood constituents. Although some substances, such as cyclophosphamide can suppress all three cell types, there are also selective effects, such as isolated thrombocytopenia under treatment with tocilizumab and JAK inhibitors. The differential diagnostic clarification of cytopenia can be difficult and necessitates a systematic work-up of the course of the disease and the subsequent treatment. The reviews of anemia, leukocytopenia and thrombocytopenia presented here summarize the most important components of the differentiation of hematological alterations in patients with rheumatic diseases.

HM71224, a selective Bruton's tyrosine kinase inhibitor, attenuates the development of murine lupus

Background

Systemic lupus erythematosus (SLE) is associated with B cell hyperactivity, and lupus nephritis (LN), in particular, is promoted by the production of autoantibodies and immune complex deposition. Bruton’s tyrosine kinase (BTK) plays critical roles in B cell receptor-related and Fc receptor-related signaling. We aimed to investigate the impact of therapeutic intervention with HM71224 (LY3337641), a selective BTK inhibitor, on the development of murine SLE-like disease features.

Methods

We examined the therapeutic effects of HM71224 on SLE-like disease features in MRL/lpr and NZB/W F1 mice. The disease-related skin lesion was macroscopically observed in MRL/lpr mice, and the impact on splenomegaly and lymphadenopathy was determined by the weight of the spleen and cervical lymph node. The renal function was evaluated by measuring blood urea nitrogen, serum creatinine, and urine protein, and the renal damage was assessed by histopathological grading. Survival rate was observed during the administration period. The impact of B cell inhibition was investigated in splenocytes from both mice using flow cytometry. Autoantibody was measured in serum by ELISA.

Results

HM71224 effectively suppressed splenic B220⁺GL7⁺, B220⁺CD138⁺, and B220⁺CD69⁺ B cell counts, and anti-dsDNA IgG and reduced splenomegaly and lymph node enlargement. The compound also prevented skin lesions caused by lupus development, ameliorated renal inflammation and damage with increased blood urea nitrogen and creatinine, and decreased proteinuria. Furthermore, HM71224 also decreased mortality from lupus development in both mouse models.

Conclusion

Our results indicate that inhibition of BTK by HM71224 effectively reduced B cell hyperactivity and significantly attenuated the development of SLE and LN in rodent SLE models.

Oxidized Hemoglobin Is Antigenic and Immunogenic in Lupus

Hemolysis-associated anemia is characteristic of diseases such as atherosclerosis, lupus, malaria, and leishmaniasis; the toxic effects of free hemoglobin (Hb) have been extensively described. This study was based on the premise that release of this sequestered, inflammatory molecule can result in deleterious immunological consequences, particularly in the context of pre-existing lupus. IgG anti-Hb responses were detected in the sera of lupus patients. Lupus-prone mice exhibited heightened plasma Hb levels, and ferric (Fe³⁺) Hb triggered preferential release of lupus-associated cytokines from splenocytes derived from aging lupus-prone mice. Anti-Hb B cell precursor frequencies were heightened in such mice, which also expressed increased titers of anti-Hb antibodies in serum and in kidney eluates. Fe³⁺ Hb preferentially increased the functional maturation of bone marrow-derived dendritic cells (BMDCs) from lupus-prone mice, effects abrogated upon the inhibition of Stat3. Hb interacted with lupus-associated autoantigens extruded during apoptosis and coincubation of Hb and apoptotic blebs had additional maturation-inducing effects on lupus BMDCs. Immunization with Hb in lupus-prone mice induced antigen spreading to lupus-associated moieties; Hb-interacting autoantigens were preferentially targeted and increased complement deposition and glomerulosclerosis were observed. Hb therefore demonstrates both antigenicity and immunogenicity and triggers specific immuno-pathological effects in a lupus milieu.

The Centenary of Immune Thrombocytopenia-Part 2: Revising Diagnostic and Therapeutic Approach

Primary immune thrombocytopenia (ITP) is the most common cause of thrombocytopenia in children and adolescents and can be considered as a paradigmatic model of autoimmune disease. This second part of our review describes the clinical presentation of ITP, the diagnostic approach and overviews the current therapeutic strategies. Interestingly, it suggests an algorithm useful for differential diagnosis, a crucial process to exclude secondary forms of immune thrombocytopenia (IT) and non-immune thrombocytopenia (non-IT), which require a different therapeutic management. Advances in understanding the pathogenesis led to new therapeutic targets, as thrombopoietin receptor agonists, whose role in treatment of ITP will be discussed in this work.

Polymorphisms in NAT2 (N-acetyltransferase 2) gene in patients with systemic lupus erythematosus

OBJECTIVE

To investigate potential associations of four substitutions in NAT2 gene and of acetylator phenotype of NAT2 with systemic lupus erythematosus (SLE) and clinical phenotypes.

METHODS

Molecular analysis of 481C>T, 590G>A, 857G>A, and 191G>A substitutions in the NAT2 gene was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique, from DNA extracted from peripheral blood samples obtained from patients with SLE (n=91) and controls (n=97).

RESULTS AND CONCLUSIONS

The 857GA genotype was more prevalent among nonwhite SLE patients (OR=4.01, 95% CI=1.18-13.59). The 481T allele showed a positive association with hematological disorders that involve autoimmune mechanisms, specifically autoimmune hemolytic anemia or autoimmune thrombocytopenia (OR=1.97; 95% CI=1.01-3.81).

Systemic lupus erythematosus in Nepal: A review

Nepal is a small country that is landlocked between India and China. Several ethnic groups live within the 147,181 km(2) of this country. Geographic diversity ranges from the high Himalayas to the flatlands of the Ganges plains. Lupus nephritis (LN), a complication of systemic lupus erythematosus (SLE), is a common kidney problem in Nepal; but the real incidence and prevalence of SLE in Nepal is largely not known. Here, it more commonly affects people (mostly women) living in the southern flatlands, but SLE is reported to be uncommon further south in India. Even though the disease appears to be common, good quality research is uncommon in Nepali literature. This article was written to provide a review of the articles published to date about SLE in Nepal and to discuss the gaps in knowledge that require further evaluation.

Relationship between prevalence and severity of restless legs syndrome and anemia in patients with systemic lupus erythematosus

AIM

Our aim was to evaluate the relationship between the prevalence and severity of restless legs syndrome (RLS) and the anemia in patients with systemic lupus erythematosus (SLE).

METHODS

This was a case-control study which was conducted at the rheumatology clinic of a university affiliated hospital, including 62 patients with SLE and 62 age- and sex-matched healthy controls. The patients were divided into two groups in terms of their hemoglobin levels. The criterion for anemia was hemoglobin level lower than 12 g/dL in females and 13 g/dL in males.

RESULTS

Nineteen patients (30.6%) in the patient group were diagnosed with RLS, and International RLS Study Group Rating Scale (IRLSSG-RS) score was 10.7 ± 9.5 (median:10.0 [range:0.0-30.0]). Three subjects (4.8%) in the control group had RLS, and the IRLSSG-RS score was 0.7 ± 3.3 (median:0.0 [range:0.0-18.0]). The prevalence of RLS and the IRLSSG-RS score were higher in the patient group than those in the control group (P < 0.001). Ten SLE patients (50%) with anemia had RLS, and their IRLSSG-RS score was 14.5 ± 9.9 (median:21.0 [range:11.0-30.0]). Nine SLE patients (21.4%) without anemia had RLS and their IRLSSG-RS was 9.0 ± 8.9 (median:21.0 [range:11.0-24.0]). Significant differences were present in the prevalence of RLS and the IRLSSG-RS score between SLE patients with and without anemia (P = 0.024, P = 0.044, respectively).

CONCLUSION

The present study demonstrated that the prevalence of RLS was higher in patients with SLE than that of the normal population. Results of this study also suggested that anemia was associated with higher frequency of and more severe RLS in patients with lupus.

Autoimmunity-associated protein tyrosine phosphatase PEP negatively regulates IFN-α receptor signaling

The protein tyrosine phosphatase PTPN22(C1858T) allelic polymorphism is associated with increased susceptibility for development of systemic lupus erythematosus (SLE) and other autoimmune diseases. PTPN22 (also known as LYP) and its mouse orthologue PEP play important roles in antigen and Toll-like receptor signaling in immune cell functions. We demonstrate here that PEP also plays an important inhibitory role in interferon-α receptor (IFNAR) signaling in mice. PEP co-immunoprecipitates with components of the IFNAR signaling complex. Pep(-/-) hematopoietic progenitors demonstrate increased IFNAR signaling, increased IFN-inducible gene expression, and enhanced proliferation and activation compared to Pep(+/+) progenitors in response to IFN-α. In addition, Pep(-/-) mice treated with IFN-α display a profound defect in hematopoiesis, resulting in anemia, thrombocytopenia, and neutropenia when compared to IFN-α-treated Pep(+/+) mice. As SLE patients carrying the PTPN22(C1858T) risk variant have higher serum IFN-α activity, these data provide a molecular basis for how type I IFNs and PTPN22 may cooperate to contribute to lupus-associated cytopenias.

Linking susceptibility genes and pathogenesis mechanisms using mouse models of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) represents a challenging autoimmune disease from a clinical perspective because of its varied forms of presentation. Although broad-spectrum steroids remain the standard treatment for SLE, they have many side effects and only provide temporary relief from the symptoms of the disease. Thus, gaining a deeper understanding of the genetic traits and biological pathways that confer susceptibility to SLE will help in the design of more targeted and effective therapeutics. Both human genome-wide association studies (GWAS) and investigations using a variety of mouse models of SLE have been valuable for the identification of the genes and pathways involved in pathogenesis. In this Review, we link human susceptibility genes for SLE with biological pathways characterized in mouse models of lupus, and discuss how the mechanistic insights gained could advance drug discovery for the disease.

Successful platelet count recovery in lupus-associated thrombocytopenia with the thrombopoietin agonist eltrombopag

Eltrombopag is a new thrombomimetic medication approved for the treatment of immune thrombocytopenia. There are very few reports on the use of eltrombopag in patients with thrombocytopenia associated with sytemic lupus.We present a recent case of a patient with lupus with severe thrombocytopenia refractory to conventional therapy and full recovery with the use of eltrombopag. The present status of the literature with the use of this medication in patients with lupus is reviewed and discussed.