Comprehensive B Cell Phenotyping Profile for Chronic Graft-versus-Host Disease Diagnosis.

Previous studies have reported single B cell-related chronic graft-versus-host disease diagnostic (cGVHD) biomarkers, such as B cell-activating factor (BAFF), CD21low, and immature B cells, but research on the performance of biomarker combinations and the covariate effect of steroids is lacking. The primary objective of this study was to determine the most accurate combination of B cell populations using cell surface staining flow cytometry in an independent cohort of patients with cGVHD. Secondary objectives included assessing the effect of corticosteroid use at sample collection on the makeup and accuracy of the diagnostic panel and identifying the mechanism underlying low surface expression of BAFF receptor (BAFF-R) on B cells in cGVHD. Flow cytometry analysis was performed in an adult cohort of post-HCT patients with cGVHD onset (n = 44) and time-matched recipients without cGVHD (n = 63). We confirmed that the onset of cGVHD was associated with higher soluble BAFF (sBAFF) levels, elevated CD27-CD10-CD21low CD19+ B cell and classical switched memory B cell counts, and reduced transitional and naïve B cell counts. The highest single B cell population area under the receiver operating characteristic (ROC) curve (AUC) was .72 for transitional type 1 CD21low B cells. We also showed a significant inverse relationship between sBAFF and surface BAFF-R expression caused by sBAFF modulation of BAFF-R. Steroid use at sample collection influenced the significance of the sBAFF:B cell ratio, naïve and marginal zone-like B cells. The optimal combination of B cell subsets most significantly associated with cGVHD onset with or without concurrent corticosteroid use resulted in ROC AUCs of .87 and .84, respectively. Transitional and CD21low B cells were the only populations present in both panels; however, analyzing only these populations resulted in ROC AUCs of .79 and .78, respectively. This suggests that the inclusion of other populations and use of different panels depending on steroid use is necessary to achieve better accuracy. sBAFF was not a component of either panel. These novel B cell profiles could be tested prospectively in patients post-HSCT and could lead to focused mechanistic studies.

Profile of BAFF and its receptors' expression in lupus nephritis is associated with pathological classes.

Background/Objective B-cell activating factor (BAFF) plays an important role in the pathogenesis of systemic lupus erythematosus. However, the role of BAFF in lupus nephritis (LN) is not understood. Our aim was to evaluate the expression of BAFF and its three receptors in renal biopsy samples from patients with LN and investigate a relationship with pathological class. Methods We conducted a prospective descriptive study (2011-2014) on 52 kidney biopsy samples from patients with LN. Immunohistochemistry for BAFF, its receptors (transmembrane activator and calcium modulator and cyclophilin ligand interaction (TACI), protein maturation of B cells (BCMA), and BAFF-receptor (BAFF-R)), and CD20 expression was performed. Samples were scored according to the percentage of cells with positive expression. Results In class II LN, BAFF-R and TACI were not expressed, whereas BCMA and BAFF were lowly expressed in the interstitial inflammatory infiltrates. Proliferative class III/IV had elevated BAFF expression in the glomeruli, and TACI was expressed in interstitial inflammatory infiltrates and the glomeruli. Interestingly, the class IV cases with vasculopathy ( n = 4) had endothelial BAFF expression, which was not visible in thrombotic microangiopathy ( n = 4). Class V was characterized by low BAFF expression in interstitial inflammatory infiltrates and by BAFF, TACI, and BCMA expression in the glomeruli. BAFF expression was associated with inflammatory scores and CD20 positive infiltrates, mainly in class IV. Conclusions Expression patterns of BAFF and its receptors differ according to LN class. Our study provides evidence that BAFF could be used as a routine marker in LN biopsies and to determine which patients will benefit from anti-BAFF therapy.

Lymphocyte antigens targetable by monoclonal antibodies in non-systemic vasculitic neuropathy.

OBJECTIVE: To identify the most relevant antigens for monoclonal antibodies in lymphocytic infiltrates in non-systemic vasculitic neuropathy (NSVN). BACKGROUND: Current immunosuppressive treatment for NSVN is insufficient. Monoclonal antibodies might be a treatment option, but the expression profile for targetable antigens on lymphocytic infiltrates in NSVN is unknown. METHODS: Sural nerve biopsies from a cohort of patients with NSVN were immunohistochemically studied for the expression of potential candidate antigens in perivascular and intramural lymphocytic infiltrates and correlated with neurological and electrophysiological parameters. 20 patients with treatment naïve NSVN and 5 patients with idiopathic axonal neuropathy were included. RESULTS: The CD52, BAFF and CD49d antigens were expressed in epineurial, perivascular or intramural lymphocytes of all (20/20) patients. CD52 was most prominently expressed in 21.49% of all inflammatory infiltrates. BAFF and CD49d were detected in 11.25% and 10.99% of these lymphocytes, respectively. The CD20, CD25 and CD126 antigens were found less frequently and at low levels only (CD20: 10/20 patients, 5.84% of lymphocytes; CD25: 17/20 patients, 5.22% of lymphocytes; CD126: 3/20 patients, 0.15% of lymphocytes). CONCLUSION: This is the first study in NSVN that identifies antigens expressed by pathogenic lymphocytes, which are potential targets for future monoclonal antibody treatment. Our data suggest that NSVN is amenable to monoclonal antibodies and, moreover, that targeting CD52 may be particularly promising. Our results strongly warrant future clinical trials in NSVN with monoclonal antibodies.

Increased visfatin levels are associated with higher disease activity in anti-Jo-1-positive myositis patients.

OBJECTIVES: The aim of this study was to evaluate serum levels of visfatin in anti-Jo-1-positive myositis patients, its expression in muscle tissue and to investigate potential relationships between visfatin, B-cell activating factor of the TNF family (BAFF), disease activity and anti-Jo-1 autoantibody levels. METHODS: Serum levels of visfatin and BAFF were measured in 38 anti-Jo-1 positive myositis patients and 35 healthy subjects. Disease activity was evaluated by myositis disease activity assessment tool (MYOACT) using visual analogue scales (VAS) and by serum muscle enzymes. Visfatin expression was evaluated by immunohistochemistry in muscle tissue of myositis patients (n=10) and compared with non-inflammatory control muscle tissue samples from patients with myasthenia gravis (n=5). RESULTS: Serum visfatin and BAFF levels were significantly higher in myositis patients compared to healthy subjects and were associated with clinical muscle activity assessed by VAS. Only serum BAFF levels, but not visfatin levels, positively correlated with muscle enzyme concentrations and anti-Jo1 antibody levels. There was a positive correlation between visfatin and BAFF serum levels in myositis patients but a negative correlation was observed in healthy subjects. Visfatin expression was up-regulated in endomysial and perimysial inflammatory infiltrates of muscle tissue from myositis patients. CONCLUSIONS: Up-regulation of visfatin in myositis muscle tissue and an association between increased visfatin levels and muscle disease activity evaluated by MYOACT in anti-Jo-1 positive myositis patients could support possible role of visfatin in the pathogenesis of myositis.

Significance of BAFF/APRIL Expression and Their Receptors in Pediatric Patients With Acute Lymphoblastic Leukemia.

In this study, we investigated the mRNA expression and protein levels of B-cell activating factor (BAFF)/a proliferation-inducing ligand (APRIL) and their receptors in acute lymphoblastic leukemia (ALL) cell lines and pediatric patients with ALL using real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blotting. The location and level of the BAFF/APRIL proteins in ALL cell lines were also detected by immunofluorescence cytochemistry and flow cytometry. Correlations between plasma protein levels of BAFF/APRIL and primary clinical parameters were analyzed. We found that BAFF/APRIL was highly expressed in pediatric ALL patients and ALL cell lines. The BAFF/APRIL proteins were located on the cell membrane, and the proportion of positive cells and mean fluorescence intensity were significantly higher than in the healthy control group (P<0.05). The mRNA expression and protein levels of BAFF/APRIL and their receptors in untreated ALL children were significantly higher than in healthy controls (P<0.05) as well as were significantly reduced in the remission group (P<0.05). The plasma protein levels of BAFF/APRIL were positively correlated with the white blood cell count, lactate dehydrogenase, and serum ferritin. Abnormal levels of BAFF/APRIL in pediatric ALL suggest that BAFF/APRIL are associated with the development and progression of ALL in children and may provide information for the development of BAFF-based and APRIL-based targeted therapies.

Effect of Hydroxychloroquine Treatment on Dry Eyes in Subjects with Primary Sjögren's Syndrome: a Double-Blind Randomized Control Study.

The effect of hydroxychloroquine (HCQ) on dry eye has not been fully determined. This study aimed to compare the 12-week efficacy of HCQ medication with that of a placebo in the management of dry eye in primary Sjögren's syndrome (pSS). A double-blind, randomized control study was conducted in 39 pSS subjects from May 2011 through August 2013. pSS was diagnosed based on the classification criteria of the American-European Consensus Group. Subjects received 300 mg of HCQ or placebo once daily for 12 weeks and were evaluated at baseline, 6, and 12 weeks, with a re-visit at 16 weeks after drug discontinuance. The fluorescein staining score, Schirmer test score, tear film break-up time (TBUT), and ocular surface disease index (OSDI) were measured, and tears and blood were collected for ESR, IL-6, IL-17, B-cell activating factor (BAFF), and Th17 cell analysis. Color testing was performed and the fundus was examined to monitor HCQ complications. Twenty-six subjects completed the follow-up. The fluorescein staining score and Schirmer test score did not differ significantly. The OSDI improved with medication in the HCQ group but was not significantly different between the groups. TBUT, serum IL-6, ESR, serum and tear BAFF, and the proportion of Th17 cells did not change in either group. HCQ at 300 mg daily for 12 weeks has no apparent clinical benefit for dry eye and systemic inflammation in pSS (ClinicalTrials.gov. NCT01601028).

Salivary and serum B-cell activating factor (BAFF) levels after hydroxychloroquine treatment in primary Sjögren's syndrome.

PURPOSE: Some evidence implicates a role of hydroxychloroquine (HQ) in the management of Sjögren's syndrome. This study evaluated the effect of HQ on saliva B-cell activating factor (BAFF) levels as well as health related quality of life (QoL) in patients with primary Sjögren's syndrome (pSS). MATERIALS AND METHODS: Ten pSS patients who had been treated with HQ for at least 2 years and 15 healthy controls (HC) were included in the study. First, HQ was withdrawn for 12 weeks, then baseline evaluation was performed. Subsequently, HQ was restarted and further evaluations were carried out after 12 and 24 weeks of HQ treatment. Oral infection foci were eliminated by dental and periodontal treatments in both groups before enrollment. BAFF levels were evaluated with ELISA in serum and unstimulated mixed saliva. Salivary flow rates of patients and the control group were measured as well. Oral health quality of life (QoL) was evaluated by an oral health impact profile-14 (OHIP-14) questionnaire. RESULTS: Salivary BAFF levels (median: 12.39 ng/ml) were significantly decreased by using HQ both at 12 (2.78 ng/ml, P = 0.008) and 24 weeks (0.54 ng/ml, P = 0.011). Similarly, decreases in serum BAFF levels (5.23 ng/ml) were seen at 12 and 24 weeks after HQ treatment (2.18 ng/ml, P = 0.008 and 0.0 ng/ml, P = 0.012, respectively). Serum and salivary BAFF levels were significantly lower in healthy controls (0.37 ng/ml and 0.0 ng/ml, resp.) compared to those of pSS before HQ therapy (P = 0.006 and P = 0.001, resp.). Unstimulated salivary flows were similar in patients treated with HQ after 12 (0.38 ml/min) and 24 weeks (0.50 ml/min) (P = 0.51) but higher than the patients' rate at baseline (0.04 ml/min) (P = 0.008). CONCLUSION: Salivary and serum BAFF levels were lowered in patients with pSS when treated with HQ. In addition, decreased disease activity and increased salivary flows can be achieved with HQ in pSS patients.

APRIL and BAFF play a key role in differentiating vitreoretinal lymphoma from uveitis.

BACKGROUND: Early diagnosis of vitreoretinal lymphoma (VRL) is critical for the successful treatment of this rare intraocular malignancy. However, fast and reliable diagnosis of VRL in patients presenting with intermediate or posterior non-infectious uveitis remains a challenge. A proliferation-inducing ligand (APRIL) and B-cell activating factor (BAFF) are vital factors in the pathophysiology, diagnosis, and prognosis of primary central nervous system lymphoma (PCNSL) and systemic autoimmune diseases. However, their utility as biomarkers for the diagnosis of VRL and uveitis remains unclear. METHODS: In this retrospective study, we analyzed APRIL and BAFF levels in the aqueous humor (AH) of 43 eyes of 40 patients, including 23 eyes of 20 patients with VRL, eight eyes of eight patients with uveitis, and 12 eyes of 12 patients with other ocular diseases (OODs). Additionally, we measured their levels after induction of chemotherapy in five eyes of five patients with VRL. RESULTS: AH levels of APRIL reliably distinguished VRL from uveitis, with a specificity of 78.3% and sensitivity of 75%. BAFF also showed similar potential. Serial AH analysis of patients with VRL during chemotherapy demonstrated a corresponding decline in AH levels of APRIL and BAFF. CONCLUSION: This study extends the spectrum of valuable diagnostic biomarkers for VRL and uveitis. In patients with uveitis, the assessment of AH APRIL may help accelerate the diagnosis of VRL. Moreover, our results underline the important role of APRIL and BAFF in therapeutic monitoring of VRL.

Therapeutic effects of TACI-Ig on rat with adjuvant arthritis.

Transmembrane activator and calcium modulator and cyclophilin ligand interactor-immunoglobulin (TACI-Ig) is a human fusion protein that binds and neutralizes both B lymphocyte stimulator (BLyS), a cytokine shown to be a key regulator of B cell maturation, proliferation and survival, and a proliferation-inducing ligand (APRIL). Rat adjuvant arthritis (AA) is an experimental animal model of rheumatoid arthritis (RA), which is mainly dependent on T cells and neutrophil-mediated cytokine production. The purpose of the present study was to investigate the effects of TACI-Ig on rat AA. Rat AA was induced by intradermal injection of 0·1 ml complete Freund's adjuvant (CFA). TACI-Ig (0·7, 2·1 and 6·3 mg/kg), recombinant human tumour necrosis factor-α receptor (rhTNFR) : Fc (2·8 mg/kg) and IgG-Fc (6·3 mg/kg) were administered subcutaneously every other day from days 16 to 34 after immunization. Arthritis was evaluated by arthritis global assessment and swollen joint count (SJC). The ankle joint and spleen were harvested for histopathological examination. Spleen index and thymus index were calculated. The levels of BLyS, interleukin (IL)-17, interferon (IFN)-γ, IgG1, IgG2a and IgM in AA rat spleen were measured by enzyme-linked immunosorbent assay. Administration of TACI-Ig significantly reduced the arthritis global assessment and SJC, decreased spleen index and ameliorated histopathological manifestations of rat AA. Suppressing the levels of BLyS, IL-17, IFN-γ and Ig in AA rat spleen were observed after administration of TACI-Ig. These results showed that TACI-Ig significantly inhibited the degree of rat AA, and the inhibitory effects might be associated with its ability to reduce BLyS, proinflammatory cytokines and Ig levels in spleen.

Preliminary findings on the possible role of B-lymphocyte stimulator (BLyS) on diabetes-related periodontitis.

The possible role of B-cell growth and differentiation-related cytokines on the pathogenesis of diabetes-related periodontitis has not been addressed so far. The aim of this study was to evaluate the effects of diabetes mellitus (DM) on the gene expression of proliferation-inducing ligand (APRIL) and B-lymphocyte stimulator (BLyS), two major cytokines associated to survival, differentiation and maturation of B cells in biopsies from gingival tissue with periodontitis. Gingival biopsies were obtained from subjects with periodontitis (n = 17), with periodontitis and DM (n = 19) as well as from periodontally and systemically healthy controls (n = 10). Gene expressions for APRIL, BLyS, RANKL, OPG, TRAP and DC-STAMP were evaluated using qPCR. The expressions APRIL, BLyS, RANKL, OPG, TRAP and DC-STAMP were all higher in both periodontitis groups when compared to the control group (p < 0.05). Furthermore, the expressions of BLyS, TRAP and RANKL were significantly higher in the subjects with periodontitis and DM when compared to those with periodontitis alone (p < 0.05). The mRNA levels of BLyS correlated positively with RANKL in the subjects with periodontitis and DM (p < 0.05). BLyS is overexpressed in periodontitis tissues of subjects with type 2 DM, suggesting a possible role of this cytokine on the pathogenesis DM-related periodontitis.

New ELISA for B cell-activating factor.

BACKGROUND: The B cell-activating factor of the TNF family (BAFF) is upregulated in autoimmune diseases, but a number of conflicting results have cast doubts on the reliability of the ELISA protocols currently used for its quantification. This situation led us to develop a new ELISA for the measurement of BAFF. METHODS: BAFF was purified for use alongside nonglycosylated recombinant BAFF. Two monoclonal antibodies (mAbs) and two polyclonal antibodies (pAbs) to BAFF were used. RESULTS: The optimization process showed that the pAb format was preferable to the mAb format as capture antibody, because the pAbs recognized the glycosylated as well as the nonglycosylated forms of BAFF. The most efficient pair of Abs involved using the unconjugated form of a goat pAb to capture BAFF and the same biotinylated goat pAb to detect bound BAFF. This ELISA was not influenced by the presence of rheumatoid factor. CONCLUSIONS: This new ELISA helped provide insights into why serum concentrations of BAFF vary between studies for a given population of patients. It is a reliable tool for the management of the diseases in which BAFF is an indication of response to therapy.

A novel bioassay for B-cell activating factor (BAFF) based on expression of a BAFF-receptor ectodomain-tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor-2 endodomain fusion receptor in human rhabdomyosarcoma cells.

B-cell activating factor (BAFF) is a type II transmembrane glycoprotein belonging to the tumour necrosis factor ligand superfamily. Active soluble forms of BAFF are generated either by cleavage of the extracellular domain or by recombinant DNA technology. The current bioassay for measuring the activity of soluble BAFF involves stimulation of the proliferation of mouse splenic B-cells in the presence of goat anti-mouse IgMmicro chain which is rather cumbersome and lengthy and yields variable results. We have therefore developed an alternative functional assay which relies on the ability of BAFF to induce an apoptotic response in human rhabdomyosarcoma cells. For this, we constructed a chimeric receptor containing the ectodomain of the MuBAFF-R--the major cell receptor for BAFF--and the endodomain of the HuTRAIL-R2--one of the two functional receptors for TRAIL--which is known to contain a death domain and trigger apoptosis. When the chimeric receptor was expressed in the TRAIL-sensitive human rhabdomyosarcoma cell line KD4 clone 21, recombinant BAFF of either human or mouse sequence stimulated apoptosis, similar to TRAIL, in a dose-dependent manner. The transfected cell population, called FL17, expressing the MuBAFF-R/ HuTRAIL-R2 thus provided the basis of a novel functional bioassay for BAFF that is simple and relatively fast to perform. The construction of the chimeric receptor, development of the transfected cells expressing this receptor and the development of sensitive and reproducible bioassays for BAFF and anti-BAFF neutralising antibodies are described.

Expression of BAFF in the trophoblast and decidua of normal early pregnant women and patients with recurrent spontaneous miscarriage.

BACKGROUND: BAFF, the B cell activation factor, is a member of the tumor necrosis factor (TNF) ligand family that binds to BCMA, TACI, and BAFF-R. Previous studies have shown that members of the TNF family are detected in human placental trophoblast cells, but the expression patterns of BAFF involved in human decidua and the differential expression of BAFF between normal pregnancy and miscarriage are still incompletely documented or unknown. This study was designed to investigate the expression of BAFF and BAFF-R in the trophoblast and decidua of normal early pregnant women and recurrent spontaneous abortion (RSA) patients. METHODS: Forty-five patients with RSA and 45 normal pregnant women were included in this study. By reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and immunohistochemical experiments, we explored the expression of BAFF and BAFF-R in the maternal-fetal interface of normal early pregnant women and RSA patients. RESULTS: Analysis by RT-PCR and Western blotting revealed that BAFF was detected in both trophoblast and decidua of all the samples, and the expression level was higher in the tissues of normal early pregnant women (P<0.05) than that of recurrent spontaneous abortion patients under the same gestational weeks. Messages for BAFF-R were absent. Immunohistochemical experiments showed that expression of BAFF was cell-specific which was localized to villous cytotrophoblast and syncytiotrophoblast cells in trophoblast and to stromal cells in decidua. Whereas BAFF was prominent on the trophoblast and decidua of normal early pregnant women, it was decreased in the tissues of RSA patients. CONCLUSIONS: BAFF might steer maternal leukocytes away from a harmful immune response and toward a favorable one and play a potentially vital role for successful pregnancy.

Biomarkers for Sjögren's syndrome.

Sjögren's syndrome (pSS) is a complex and heterogeneous disorder characterized by different clinical subsets. Recently, great efforts have been made searching for reliable biomarkers able to ameliorate the diagnostic algorithm and the prognostic stratification of pSS patients and ultimately allowing the scientific community to address some of the unmet needs for the disease. In this review, we have summarized the state of the art of 'traditional' widely acknowledged clinical, serological and histologic biomarkers for pSS with the aim of highlighting their relevance and limitations in clinical practice. We have also explored some of the novel potential biomarkers that have been proposed more recently, potentially able to open new ways in the assessment of the disease.

Comparison of non-invasive biomarkers faecal BAFF, calprotectin and FOBT in discriminating IBS from IBD and evaluation of intestinal inflammation.

Faecal calprotectin and faecal occult blood test (FOBT) were widely used in the diagnosis and assessment of intestinal inflammation in inflammatory bowel disease (IBD). Recently we identified an excellent new biomarker B cell-activating factor (BAFF) for IBD. Here in this study we compared the efficacy of faecal BAFF, calprotectin and FOBT to find the "best non-invasive marker". Results showed that for discriminating IBD from IBS, BAFF ≥227.3 pg/ml yield 84% sensitivity, 100% specificity, 100% positive predictive value (PPV) and 64% negative predictive value (NPV) while calprotectin ≥50 µg/g yield 76% sensitivity, 93% specificity, 97% PPV and 53% NPV. FOBT yield 65% sensitivity, 93% specificity, 97% PPV and 43% NPV. Combining BAFF with calprotectin tests yield 94% sensitivity, 93% specificity, 98% PPV, 81% NPV. Faecal BAFF level showed the stronger correlation with endoscopic inflammatory score as compared to calprotectin not only in UC (correlation coefficient [r] = 0.69, p < 0.0001 vs. r = 0.58, p < 0.0001), but also in CD (r = 0.58, p < 0.0001 vs. r = 0.52, p = 0.0003). Our results indicating that faecal BAFF is a promising non-invasive biomarker in IBD differential diagnosis and monitoring of intestinal inflammation.

Predictive biological markers of systemic lupus erythematosus flares: a systematic literature review.

BACKGROUND: The aim of this study was to identify the most reliable biomarkers in the literature that could be used as flare predictors in systemic lupus erythematosus (SLE). METHODS: A systematic review of the literature was performed using two databases (MEDLINE and EMBASE) through April 2015 and congress abstracts from the American College of Rheumatology and the European League Against Rheumatism were reviewed from 2010 to 2014. Two independent reviewers screened titles and abstracts and analysed selected papers in detail, using a specific questionnaire. Reports addressing the relationships between one or more defined biological test(s) and the occurrence of disease exacerbation were included in the systematic review. RESULTS: From all of the databases, 4668 records were retrieved, of which 69 studies or congress abstracts were selected for the systematic review. The performance of seven types of biomarkers performed routinely in clinical practice and nine types of novel biological markers was evaluated. Despite some encouraging results for anti-double-stranded DNA antibodies, anti-C1q antibodies, B-lymphocyte stimulator and tumour necrosis factor-like weak inducer of apoptosis, none of the biomarkers stood out from the others as a potential gold standard for flare prediction. The results were heterogeneous, and a lack of standardized data prevented us from identifying a powerful biomarker. CONCLUSIONS: No powerful conclusions could be drawn from this systematic review due to a lack of standardized data. Efforts should be undertaken to optimize future research on potential SLE biomarkers to develop validated candidates. Thus, we propose a standardized pattern for future studies.

A Review of Clinical Trials of Belimumab in the Management of Systemic Lupus Erythematosus.

There have been few changes over the last 50 years in the treatment of Systemic lupus erythematosus (SLE), using non-specific anti-inflammatory agents such as: nonsteroidal anti-inflammatory drugs along with the immune cell modulating agent hydroxychloroquine for mild disease, and broad spectrum immunosuppressants plus antiinflammatories such as corticosteroids, azathioprine, cyclophosphamide, or mycophenolate during flares or severe disease with organ involvement. In some patients, the response is inadequate and side effects appear from mild unpleasant up to severe toxicity. Drug metabolism and clearance may be severely compromised. Therefore, it is a priority to develop better treatments with fewer adverse events that can be used at different stages of disease activity. In recent years, a member of the tumor necrosis factor (TNF) family, soluble human B Lymphocyte Stimulator protein (BLyS), also referred to as B-cell activating factor (BAFF) and TNFSF13B has been studied extensively. This protein is synthesized by myeloid cell lines, specifically interacts with B lymphocytes and increases their life-span. BlyS plays a key role in the selection, maturation and survival of B cells and it has a significant role in the pathogenesis of SLE. In this review, we analyzed the role of BLyS as a diagnostic/prognostic marker and/or therapeutic target for lupus patients, and the different clinical studies published using belimumab.

Characterization of B-Cells in tonsils of patients diagnosed with pediatric autoimmune neuropsychiatric disorder associated streptococcus.

OBJECTIVE: To determine if Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcus (PANDAS) patients demonstrate a significantly different number of B-Cells or markers of activity when compared to recurrent Group A Streptococcus or Obstructive Sleep Apnea patients. STUDY DESIGN: Prospective Cohort Study. STUDY SETTING: Academic University Hospital. METHODS: Tonsil tissue was collected from twenty-two patients in the operating room and organized into three groups. Ten clinically diagnosed PANDAS, six Group A Streptococcus and six Obstructive Sleep Apnea patients were included in this study. Each tissue sample was extracted with MSD Tris Lysis Buffer and protein lysates were analyzed for CD 19, B-Cell Activating Factor and B-Cell Activating Receptor by western blot methods. RESULTS: Based on ANOVA analysis, there was no significant difference in the expression of B-Cell Activating Factor, B-Cell Activating Receptor or CD 19 when comparing the three study groups by western blot analysis methods. CONCLUSIONS: In this prospective cohort study, it appears that PANDAS patients do not demonstrate increased number of B-Cells, expression of B-Cell Activating Factor or B-Cell Activating Receptor when compared to Group A Streptococcus or Obstructive Sleep Apnea cohorts. As a result, further evaluation of the cell-mediated immune system is warranted to provide further insight into the pathophysiology of PANDAS. In addition, we must investigate if PANDAS patients only demonstrate increased B-Cell number or activity when undergoing an acute Tic/OCD exacerbation.