BAFF Levels Research Articles

IL-14α as a Putative Biomarker for Stratification of Dry Eye in Primary Sjögren's Syndrome.

BackgroundDry eye is often the first presenting manifestation of primary Sjögren’s syndrome (pSS). Because of the high prevalence of dry eye disease in normal population, ophthalmologists urgently need a non-invasive and reliable screening test to diagnose dry eye associated SS patients, other than ocular symptoms and signs. Currently, there is no single test available. The correlation of serum IL-14α with pSS has been found in pSS mouse model.PurposeTo evaluate whether IL-14α can serve as a biomarker to stratify dry eye in primary Sjögren’s syndrome and its correlation to BAFF in a cohort of patients with non-SS dry eye (NSDE), pSS with dry eye disease, rheumatoid arthritis (RA), and healthy controls (HC).MethodsRetrospective study based on serum levels of IL-14α (defined by Western Blot) and BAFF (measured by ELISA) were evaluated among pSS with dry eye disease, NSDE, RA, and HC groups. Serum levels of SS related autoantibodies (Ro, La, SP1, PSP, and CA6) were also measured by ELISA.ResultsOne hundred and eighty patients were included for the current study, patients were separated into four groups as defined by pSS (n=65), NSDE (n=20), RA (n=50) and HC (n=45). The level of serum IL-14α in pSS was significantly higher compared to NSDE, RA, and HC (p=0.0011, p=0.0052 and p<0.0001, respectively). The levels of serum BAFF in pSS was significantly higher than in NSDE and HC (p=0.0148 and p<0.0001, respectively, whereas the levels of serum BAFF in RA was only significantly higher than in HC (p=0.001), but the level of BAFF was no significant difference between pSS and RA. In pSS, there was a decrease in the serum levels of IL-14α associated with a longer duration of the disease. Also, there was a correlation between the serum levels of IL-14α and SS related autoantibodies such as anti-SSA/Ro and anti-SSB/La in pSS patients.ConclusionsThis is the first paper to report both IL-14α and BAFF could serve as a critical cytokine biomarker for the stratification of dry eye in primary Sjögren’s syndrome. This may help ophthalmologists to develop non-invasive metrics for the diagnosis of dry eye associated pSS.

Impact of B cell-depletion on plasma cells in a pre-clinical model of meningeal inflammation and subpial demyelination

Abstract Anti-CD20 B cell depletion therapy has provided evidence for the pathogenic roles of B cells in multiple sclerosis (MS). Terminally differentiated plasma cells (PCs) are spared by anti-CD20, and our lab has previously shown that during experimental autoimmune encephalomyelitis (EAE), IgA+ PCs mediate protection against neuroinflammation. One hypothesis is that in addition to depleting pro-inflammatory B cells, anti-CD20 also removes the major consumers of BAFF (i.e. B cells) thus promoting a favourable niche for regulatory PCs and may represent an additional mechanism by which anti-CD20 therapy confers protection. Adoptive transfer EAE of PLP-primed Th17 cells into SJL/J mice leads to ascending paralysis and meningeal inflammation which parallels brain pathology seen in human MS. Mice were prophylactically treated with anti-CD20 (10mg/kg) or isotype control antibodies which we re-administered throughout the course of the experiment and monitored daily for clinical symptoms. We find that anti-CD20 treatment effectively depleted B cells (but not T cells) in the periphery; within the central nervous system, meningeal immune clusters formed in both anti-CD20 and isotype control treated mice, with the former being devoid of B220+ B cells. Compared to control treated mice, anti-CD20 treated mice showed limited subpial demyelination and pathology adjacent to B cell-less meningeal immune clusters, and is accompanied by a reduction in clinical score. In the serum, anti-CD20 treatment elevated levels of BAFF and IgA, which inversely correlated with disease severity. We thus propose that anti-CD20 exerts its protective effects by providing a favourable niche for suppressive IgA+ PCs.

Altered expression profile of BAFF receptors on peripheral blood B lymphocytes in Graves\u2019 disease

BackgroundB lymphocyte activating factor (BAFF) is a growth factor regulating B lymphocytes survival and maturation. Serum BAFF levels were elevated in patients affected with autoimmune thyroid diseases (AITD), including Graves’ disease (GD) and Hashimoto’s thyroiditis (HT). The aim of this study is to explore the association of expression levels of BAFF and its receptors with AITD.MethodsFifty-two GD patients, 39 Hashimoto’s thyroiditis (HT) patients and 23 healthy controls (HC) were recruited in this study. Serum BAFF levels were measured by ELISA. Expression of BAFF receptors, including BAFF receptor 3 (BR3) and transmembrane activator and calcium-modulating and cyclophilin ligand interactor (TACI), on B lymphocytes were analyzed by flowcytometry. Effects of steroids on serum BAFF levels and expression of BR3 and TACI were also observed in 10 patients with Graves’ orbitopathy (GO) receiving steroids therapy.ResultsSerum BAFF levels were significantly elevated from 0.93 ± 0.24 ng/ml in HC to 1.18 ± 0.33 ng/ml in GD (P = 0.0027) and 1.02 ± 0.24 ng/ml in HT (P = 0.0331). BR3 expression on peripheral B lymphocytes were elevated in GD (mean MFI: 4.52 ± 2.06 in GD vs. 3.00 ± 0.87 in HC, P = 0.0015), while TACI expression on peripheral B lymphocytes were decreased in GD without significance (mean MFI: 7.96 ± 4.06 in GD vs. 9.10 ± 3.37 in HC, P = 0.1285). Expression of BR3 and TACI was not changed significantly in HT patients. Steroids significantly suppressed serum BAFF concentrations (from 1.18 ± 0.27 ng/ml to 0.97 ± 0.10 ng/ml, P = 0.0364) and BR3 expression in GO patients (mean MFI from 6.26 ± 4.91 to 4.05 ± 1.58, P = 0.0083).ConclusionsAltered expression of BAFF and its receptor may mediate the autoimmunity in GD. Restoring the normal expression profile of receptors for BAFF could be a new strategy to treat GD.

Short-term effect of low-dose rituximab on myasthenia gravis with muscle-specific tyrosine kinase antibody.

The study aims to investigate the short-term efficacy of low-dose rituximab and its effect on immunological biomarker levels in myasthenia gravis (MG) patients with antibodies against muscle-specific tyrosine kinase (MuSK-MG). Twelve MuSK-MG patients were enrolled in this prospective, open-label, self-controlled pilot study. Clinical severity was evaluated at baseline and 6mo after a single rituximab treatment (600 mg). B lymphocyte subtypes, MuSK antibody titers, together with levels of immunoglobulins, serum B-cell activating factor (BAFF), a proliferation-inducing ligand (APRIL), soluble CD40L, and four exosomal microRNAs were evaluated. A correlation matrix to reveal pairwise relationships among above variables was also generated. The single rituximab treatment significantly lowered the clinical severity scores and reduced daily dosage of prednisone (P=.032) at 6mo. MuSK antibody titers decreased (P=.035) without significant changes in immunoglobulin levels. Serum BAFF level increased (P=.010), which negatively correlated with the percentages of B cells in lymphocytes as well as clinical severity. Additionally, serum exosomal miR-151a-3p showed a reduction of 28.1% (P=.031). We confirmed the clinical efficacy of low-dose rituximab in MuSK-MG, accompanied by a decrease in MuSK antibody titers and an increase in serum BAFF. Serum BAFF levels negatively correlated with B-cell counts as well as clinical severity.

Serum markers of B‐cell activation in pregnant women with atopic asthma

ProblemAs maternal atopy represents a risk factor for the development of atopy in offspring, we aimed to assess how pregnancy affects B‐cell activation markers in women with atopic asthma and whether they correlate with risk manifestations for allergy in newborns from mothers with atopic asthma.Method of StudyPregnant women with atopic asthma (AP) in the third trimester of gestation and nonpregnant women with atopic asthma (ANP) were prospectively recruited and compared to respective healthy counterparts (HP and HNP). All pregnant women were also assessed during the postpartum period until 6 weeks after delivery (HP/PP and AP/PP). Newborns were clinically evaluated at the age of 6 months. Peripheral blood samples were taken from each woman at each time point. Soluble CD23 (sCD23), B‐cell activating factor (BAFF), IgA, IgG, IgM, kappa (κ), and lambda (λ) free light chains (FLC) were quantified in serum samples.ResultsThe AP group presented increased sCD23 (p < 0.05) and BAFF (p < 0.001) levels compared to the ANP group and even higher levels of sCD23 during the postpartum period (p < 0.001). Moreover, the cutoffs of 6.74 g/L for IgG (sensitivity 90.9%, specificity 77.8%) and of 11.30 mg/L for λ FLC (sensitivity 81.8%, specificity 88.9%) in the AP group were predictive factors for the manifestation of allergy in their offspring.ConclusionsAfter delivery, the dynamics of sCD23 and BAFF changed significantly in the AP group. Furthermore, we found novel predictive factors for allergy manifestations in the children of these women, with potential clinical application.

Investigating the Role of BAFF and Its Receptors in Renal Transplant Recipients with Chronic Antibody-Mediated Rejection.

Background Kidney transplantation is the best treatment option for end stage renal disease (ESRD), but graft rejection is still a big obstacle that occurs in spite of immunosuppressive therapy. B cells are considered as the major reason for renal graft rejection because of antibody production. Due to their roles in B cell function, we intended to evaluate the B cell activating factor (BAFF) and its receptors including BAFF receptor (BAFF-R), B cell maturation antigen (BCMA), and transmembrane activator and cyclophilin ligand interactor (TACI) in renal transplant patients. Method The study included 40 kidney allograft patients with cAMR, 40 stable kidney allograft patients, and 8 healthy volunteers with normal kidney function. The percentage and absolute number of CD19+ B cells were analyzed by flow cytometry, the serum level of BAFF was analyzed by ELISA, and mRNA expressions of BAFF and BAFF receptors (BAFF-R, BCMA, and TACI) were measured using quantitative real-time PCR. Results The percentage and the absolute number of B cells decreased significantly in stable and cAMR patients compared to healthy individuals. The serum level and gene expression of BAFF, as well as the mRNA level of BCMA, were increased significantly in both cAMR and stable patients compared to healthy volunteers. There was an overexpression of TACI mRNA in cAMR patients compared to stable patients. Conclusions Both soluble protein and mRNA transcript of BAFF increased in transplant recipients. However, BAFF neither at the serum level nor at the mRNA transcript level cannot be a good biomarker for the prediction of cAMR. In addition, expression of TACI, compared to other receptors of BAFF, confers a potential to be used in distinguishing cAMR and stable kidney transplant patients.

Exploring the role of BAFF as biomarker in the detection of uveal melanoma metastases.

While B-cell activating factor (BAFF) was identified to promote the invasion in other malignancies, its role in the progression of uveal melanoma (UM) still remains unexplored. Here, we analysed the serum level of BAFF in UM patients with regard to its significance as biomarker for the metastases. In this retrospective study, serum BAFF levels in 173 UM patients (36 with metastases and 137 without), and 23 healthy controls were measured with a multiplexed sandwich ELISA system and then correlated with clinicopathological characteristics such as primary tumor size, tumor location, histological cell type, sex, cancer stage, cytogenetic alterations of chromosome 3, and the metastatic burden. Immunohistochemical staining of 50 UM tissue specimens was also performed to evaluate the expression of BAFF and its receptors BAFF-R and TACI. The metastatic patients were identified to have significantly higher serum BAFF levels (mean ± SD, 1520.8 ± 1182.1pg/ml) than those without metastases (950.4 ± 494.6pg/ml) and controls (810.3 ± 140.5pg/ml). While no distinctions were detected with regard to tumor location, histological cell type, gender, and monosomy 3, the patients in cancer stages II, III, and IV displayed higher serum BAFF levels than those in stage I. The serum BAFF level was significantly correlated with the metastatic burden. The serum BAFF level of 1120pg/ml was identified to have the best performance for distinguishing the metastatic patients from non-metastatic patients. In the kinetic study, we noticed that 20.8% of the analysed patients already demonstrated elevated serum BAFF concentrations before the clinical diagnosis of metastases. Positive BAFF staining was detected in the cytoplasm of single tumor cells (in 13 specimens), macrophages (in 12 specimens), and tumor-infiltrating lymphocytes (TILs) (in 13 specimens). The expressions of BAFF-R and TACI were also observed in 17 and 36 of the 50 tested UM specimens, respectively. Our study first suggests that BAFF might be a promising serum marker for the detection of UM metastases.

B cell\u2010activating factors in autoimmune pulmonary alveolar proteinosis

BackgroundAutoimmune pulmonary alveolar proteinosis (APAP) results from the suppression of granulocyte-macrophage colony-stimulating factor (GM-CSF) signaling by a neutralizing autoantibody against GM-CSF. B cell-activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are involved in immunoglobulin G production and are overproduced in various autoimmune disorders. We hypothesized that BAFF and/or APRIL levels would be elevated in serum and bronchoalveolar lavage fluid (BALF) and serum and BALF levels of BAFF and APRIL respond to the treatments (whole lung lavage (WLL) or inhalation of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF)) in patients with APAP.Subjects and methods BAFF and APRIL levels in serum and BALF from 110 patients with APAP were measured at baseline and during and after treatment, using an enzyme-linked immunosorbent assay kit. We enrolled 34 healthy volunteers as serum cytokine controls, and 13 disease controls for BALF. Associations of BAFF and APRIL levels with clinical measures were assessed to clarify their clinical roles.ResultsIn patients with APAP, serum BAFF and APRIL levels were significantly increased relative to healthy volunteers (p < 0.0001 and p < 0.05, respectively), and BALF BAFF and APRIL levels were significantly increased versus disease controls (p < 0.0001 and p < 0.01, respectively). Serum BAFF levels (but not APRIL levels) were significantly correlated with Krebs von den Lungen-6 (KL-6), surfactant protein (SP)-D, SP-A, and lactate dehydrogenase (p < 0.0001). There was no significant correlation between serum BAFF or APRIL levels and anti-GM-CSF autoantibody. BAFF and APRIL were negatively correlated with single-breath diffusion capacity for carbon monoxide (DLco) (p = 0.004) and forced vital capacity (p = 0.04), respectively. BAFF (but not APRIL) in BALF was negatively correlated with vital capacity (p = 0.04) and DLco (p = 0.006). There were significant correlations between disease severity and BAFF levels in serum (p = 0.04) and BALF (p = 0.007). Serum levels of anti-GM-CSF autoantibody, BAFF, and APRIL were not significantly affected by WLL or inhalation of recombinant human GM-CSF.ConclusionsBAFF and APRIL levels of sera and BALF in APAP were significantly increased compared with healthy volunteer and disease control, and the BAFF and APRIL pathway might have important specific roles in pathogenesis of APAP. Our data suggest a new perspective of future treatment for APAP.

Bronchoalveolar Lavage Fluid Reflects a TH1-CD21low B-Cell Interaction in CVID-Related Interstitial Lung Disease.

BackgroundAbout 20% of patients with common variable immunodeficiency (CVID) suffer from interstitial lung disease (ILD) as part of a systemic immune dysregulation. Current understanding suggests a role of B cells in the pathogenesis based on histology and increased levels of BAFF and IgM associated with active disease corroborated by several reports which demonstrate the successful use of rituximab in CVID-ILD. It is debated whether histological confirmation by biopsy or even video-assisted thoracoscopy is required and currently not investigated whether less invasive methods like a bronchoalveolar lavage (BAL) might provide an informative diagnostic tool.ObjectiveTo gain insight into potential immune mechanisms underlying granulomatous and lymphocytic interstitial lung disease (GLILD) and to define biomarkers for progressive ILD by characterizing the phenotype of B- and T-cell populations and cytokine profiles in BAL fluid (BALF) of CVID-ILD compared to sarcoidosis patients and healthy donors (HD).MethodsSixty-four CVID, six sarcoidosis, and 25 HD BALF samples were analyzed by flow cytometric profiling of B- and T-cells and for cytokines by ELISA and Multiplexing LASER Bead technology.ResultsBoth sarcoidosis and CVID-ILD are characterized by a predominantly T-cell mediated lymphocytosis in the BALF. There is an increase in T follicular helper (TFH)-like memory and decrease of regulatory T cells in CVID-ILD BALF. This TFH-like cell subset is clearly skewed toward TH1 cells in CVID-ILD. In contrast to sarcoidosis, CVID-ILD BALF contains a higher percentage of B cells comprising mostly CD21low B cells, but less class-switched memory B cells. BALF analysis showed increased levels of APRIL, CXCL10, and IL-17.ConclusionUnlike in sarcoidosis, B cells are expanded in BALF of CVID-ILD patients. This is associated with an expansion of TFH- and TPH-like cells and an increase in APRIL potentially supporting B-cell survival and differentiation and proinflammatory cytokines reflecting not only the previously described TH1 profile seen in CVID patients with secondary immune dysregulation. Thus, the analysis of BALF might be of diagnostic value not only in the diagnosis of CVID-ILD, but also in the evaluation of the activity of the disease and in determining potential treatment targets confirming the prominent role of B-cell targeted strategies.

BAFF promotes heightened BCR responsiveness and manifestations of chronic GVHD after allogeneic stem cell transplantation

Patients with chronic graft-versus-host disease (cGVHD) have increased B cell–activating factor (BAFF) levels, but whether BAFF promotes disease after allogeneic bone marrow transplantation (allo-BMT) remains unknown. In a major histocompatibility complex–mismatched model with cGVHD-like manifestations, we first examined B-lymphopenic μMT allo-BMT recipients and found that increased BAFF levels in cGVHD mice were not merely a reflection of B-cell number. Mice that later developed cGVHD had significantly increased numbers of recipient fibroblastic reticular cells with higher BAFF transcript levels. Increased BAFF production by donor cells also likely contributed to cGVHD, because BAFF transcript in CD4+ T cells from diseased mice and patients was increased. cGVHD manifestations in mice were associated with high BAFF/B-cell ratios and persistence of B-cell receptor (BCR)–activated B cells in peripheral blood and lesional tissue. By employing BAFF transgenic (Tg) mice donor cells, we addressed whether high BAFF contributed to BCR activation in cGVHD. BAFF increased NOTCH2 expression on B cells, augmenting BCR responsiveness to surrogate antigen and NOTCH ligand. BAFF Tg B cells had significantly increased protein levels of the proximal BCR signaling molecule SYK, and high SYK protein was maintained by BAFF after in vitro BCR activation or when alloantigen was present in vivo. Using T cell–depleted (BM only) BAFF Tg donors, we found that BAFF promoted cGVHD manifestations, circulating GL7+ B cells, and alloantibody production. We demonstrate that pathologic production of BAFF promotes an altered B-cell compartment and augments BCR responsiveness. Our findings compel studies of therapeutic targeting of BAFF and BCR pathways in patients with cGVHD.

Enhanced BAFF expression is negatively correlated with a suppressed isotype-switched memory B cell pool in CVID patients with complications

Common variable immunodeficiency (CVID) is a primary immunodeficiency due to selected genetic defects. This syndrome is frequently associated with non-infectious complications such as interstitial lung disease, enteropathy, autoimmunity and malignancies, with lack of isotype-switched B cells. B cell–activating factor (BAFF) is one of the TNF family members important for IgA class switching and plasma cell survival. Excessive levels of BAFF are found in CVID patients. In this study, we investigated the correlation of BAFF levels with isotype-switched memory B cells. Serum BAFF levels in 70 CVID patients and 15 healthy controls were measured by ELISA. The percentages of isotype switched-memory B cells were measured by flow cytometry. The correlation between BAFF and isotype-switched memory B cells in CVID patients with and without complications were analyzed by Pearson’s correlation. The serum BAFF levels in all CVID patients were significantly higher than healthy controls (p<0.0001), whereas BAFF levels are higher in the group with non-infectious complications than the group without complications (p <0.005). In contrast, isotype-switched memory B cells were significantly lower in CVID patients than healthy controls (p <0.001). Furthermore, BAFF levels in all CVID patients and the group with complications were negatively correlated to isotype-switched memory B cells (p=0.012). Our data suggests that excessive BAFF expression in CVID patients with non-infectious complications may cause suppression of memory B cell switching. Alternatively exhaustive switching memory B cell pools in CVID patient may drive upregulation of BAFF, promoting the non-infectious complications. Future study to reveal the underlying mechanism is needed.

Differential serum interferon-β levels in autoimmune thyroid diseases.

IntroductionInterferon (IFN)-β is known as an environmental trigger for the occurrence of autoimmune thyroid disease (AITD). However, the association of another type-1 IFN, IFN-β, with AITD is unknown.Material and methodsIn the study, we explored the association of serum IFN-β levels with AITD in an ethnic Chinese (i.e., Taiwanese) population. We enrolled 160 patients with Graves’ disease (GD), 47 patients with Hashimoto’s thyroiditis (HT), and 119 healthy controls. Serum IFN-β and B-cell activating factor (BAFF) levels were quantified in healthy controls at the baseline and in patients with AITD either prior to receiving medication or while under medication. Thyroid function and thyroid-stimulating hormone receptor antibody (TSHRAb) levels were measured at the time of serum collection.ResultsSerum IFN-β levels were lower in the HT group than in the control group (p = 0.031). A significant inverse correlation was observed between IFN-β and TSHRAb levels in men with GD (r = –0.433, p = 0.044). Serum IFN-β levels were also negatively associated with BAFF levels in men with GD, HT, and AITD (r = –0.320, p = 0.032; r = –0.817, p = 0.047; and r = –0.354, p = 0.011, respectively), but not in women with GD, HT, or AITD.ConclusionsSerum IFN-β levels were lower in HT patients. Correlations of serum IFN-β with TSHRAb and BAFF levels were found to be gender-specific. Further well-designed studies with larger sample sizes are required to confirm our findings.

B Cell-Activating Factor Promotes B Cell Survival in Ectopic Lymphoid Tissues in Nasal Polyps.

Ectopic lymphoid tissues (eLTs) characterized by B cell aggregation contribute to the local immunoglobulin production in nasal polyps (NPs). B cell-activating factor (BAFF) is vital for B cell survival, proliferation, and maturation. The purpose of this study is to investigate whether BAFF is involved in the B cell survival and eLT formation in NPs. The mRNA and protein levels of BAFF in NP tissues with and without eLTs were detected by PCR and ELISA assay, respectively. The cellular sources of BAFF and active caspase-3-positive B cells in NPs were studied by immunofluorescence staining. B cells purified from NP tissues were stimulated with BAFF and were analyzed by flow cytometry. Stromal cells purified from NP tissues were stimulated with lymphotoxin (LT) α1β2, and BAFF levels in culture supernatants were analyzed by ELISA. Compared with those in control tissues and NPs without eLTs, the BAFF levels were elevated in NPs with eLTs. Abundant BAFF-positive cells and few active caspase-3-positive apoptotic B cells were found in NPs with eLTs, in contrast to those in NPs without eLTs. There was a negative correlation between the numbers of BAFF-positive cells and frequencies of apoptotic B cells in total B cells in NP tissues. BAFF protected nasal polyp B cells from apoptosis in vitro. Stromal cells were an important cellular source of BAFF in NPs with eLTs. LTα1β2 induced BAFF production from nasal stromal cells in vitro. We propose that BAFF contribute to eLT formation in NPs by promoting B cell survival.

A longitudinal study of plasma BAFF levels in mothers and their infants in Uganda, and correlations with subsets of B cells.

Malaria is a potentially life-threatening disease with approximately half of the world’s population at risk. Young children and pregnant women are hit hardest by the disease. B cells and antibodies are part of an adaptive immune response protecting individuals continuously exposed to the parasite. An infection with Plasmodium falciparum can cause dysregulation of B cell homeostasis, while antibodies are known to be key in controlling symptoms and parasitemia. BAFF is an instrumental cytokine for the development and maintenance of B cells. Pregnancy alters the immune status and renders previously clinically immune women at risk of severe malaria, potentially due to altered B cell responses associated with changes in BAFF levels. In this prospective study, we investigated the levels of BAFF in a malaria-endemic area in mothers and their infants from birth up to 9 months. We found that BAFF-levels are significantly higher in infants than in mothers. BAFF is highest in cord blood and then drops rapidly, but remains significantly higher in infants compared to mothers even at 9 months of age. We further correlated BAFF levels to P. falciparum-specific antibody levels and B cell frequencies and found a negative correlation between BAFF and both P. falciparum-specific and total proportions of IgG+ memory B cells, as well as CD27− memory B cells, indicating that exposure to both malaria and other diseases affect the development of B-cell memory and that BAFF plays a part in this. In conclusion, we have provided new information on how natural immunity against malaria is formed.

Circulating BAFF and CXCL10 levels predict response to pegylated interferon in patients with HBeAg-positive chronic hepatitis B.

B-cell activating factor (BAFF), an essential cytokine for B lymphocytes activation, has been implicated in the pathogenesis of chronic viral hepatitis. However, the role of BAFF in patients with chronic hepatitis B (CHB) undergoing antiviral therapy is unknown. Patients with HBeAg-positive CHB treated with 48-week pegylated interferon (PEG-IFN; n = 42), who had stored plasma samples during treatment were recruited. Serial plasma levels of BAFF and C-X-C motif chemokine 10 (CXCL10) during therapy were measured. Combined response (CR), defined as HBeAg seroconversion with HBV DNA < 2,000 IU/mL plus HBsAg decline ≥ 1 log10 IU/mL at 24 weeks post-treatment, was achieved in 11 (26.2%) patients. BAFF levels were elevated during treatment but decreased to pre-treatment levels after PEG-IFN cessation in both responders and non-responders. Low baseline BAFF (< 770 pg/ml) and high CXCL10 (≥ 320 pg/ml) levels were independently associated with CR in multivariate analysis. Baseline CXCL10/BAFF ratio of ≥ 0.45 was predictive of CR with positive and negative predictive values of 61.5 and 89.7%, respectively. In summary, low baseline BAFF and high CXCL10 levels were associated with treatment response to PEGIFN. The combined measurement of these immune markers may help individualized decision-making in patients with HBeAg-positive CHB.

Plasma B-cell activating factor levels and polymorphisms in hepatitis B-related hepatocellular carcinoma: Clinical correlation and prognosis.

B-cell activating factor (BAFF), an important cytokine for B lymphocyte activation, has been shown to be increased in chronic hepatitis B virus (HBV) infection. This study aimed at evaluating clinical correlation and prognostic role of plasma BAFF and related polymorphisms in patients with HBV-related hepatocellular carcinoma (HCC). Plasma BAFF levels were measured from 100 healthy controls and 490 patients with chronic HBV infection (200 with HCC and 290 without HCC). The rs9514828 and rs12583006 polymorphisms were determined by allelic discrimination. The HCC group had significantly higher BAFF levels compared with the non-HCC group and healthy controls. Among the non-HCC group, the HBeAg-positive subgroup had higher BAFF levels compared with the HBeAg-negative subgroup. In the HCC group, high BAFF levels at initial presentation significantly correlated with alpha-fetoprotein levels, Child-Pugh classification, tumor size and BCLC stage. Multivariate analyses showed that elevated BAFF concentration (± 1,100 pg/ml) was a significant and independent prognostic factor of overall survival in patients with HCC (OR = 2.28, 95%CI: 1.07-4.87; P = 0.034). HCC patients with high BAFF levels (± 1,100 pg/ml) had a poorer median survival than those with low levels (P < 0.001, log-rank test). Regarding BAFF polymorphisms, the frequency of rs9514828 CT + TT genotypes was higher distributed in patients with chronic HBV infection compared with healthy controls (58.0% vs. 46.0%, P = 0.029). Our data demonstrate for the first time that elevated plasma BAFF levels at baseline exhibit clinical correlation in terms of disease severity and overall survival in HCC patients. Thus, plasma BAFF at initial diagnosis could serve as a prognostic marker for HBV-related HCC.

BAFF receptor antibody for mantle cell lymphoma therapy

ABSTRACT Mantle cell lymphoma (MCL) is an aggressive form of B cell non-Hodgkin’s lymphoma and remains incurable under current treatment modalities. One of the main reasons for treatment failure is the development of drug resistance. Accumulating evidence suggests that B cell activating factor (BAFF) and BAFF receptor (BAFF-R) play an important role in the proliferation and survival of malignant B cells. High serum BAFF levels are often correlated with poor drug response and relapse in MCL patients. Our study shows that BAFF-R is expressed on both MCL patient cells and cell lines. BAFF-R knockdown leads to MCL cell death showing the importance of BAFF-R signaling in MCL survival. Moderate knockdown of BAFF-R in MCL cells did not affect its viability, but sensitized them to cytarabine treatment in vitro and in vivo, with prolonged mice survival. Anti-BAFF-R antibody treatment promoted drug-induced MCL cell death. Conversely, the addition of recombinant BAFF (rhBAFF) to MCL cells protected them from cytarabine-induced apoptosis. We tested the efficacy of a humanized defucosylated ADCC optimized anti-BAFF-R antibody in killing MCL. Our data show both in vitro and in vivo efficacy of this antibody for MCL therapy. To conclude, our data indicate that BAFF/BAFF-R signaling is crucial for survival and involved in drug resistance of MCL. Targeting BAFF-R using BAFF-R antibody might be a promising therapeutical strategy to treat MCL patients resistant to chemotherapy.

B-cell activating factor (BAFF) expression is associated with Crohn's disease and can serve as a potential prognostic indicator of disease response to Infliximab treatment

BackgroundSeveral studies correlated elevated B-cell activating factor (BAFF) levels and its polymorphisms (SNPs) in patients with autoimmunity. Limited data existed regarding the role of BAFF in Crohn's Disease (CD) susceptibility and/or treatment response to infliximab. AimThis study aims to evaluate BAFF expression in CD patients, investigate if its expression can predict response to infliximab treatment, and examine the association of BAFF SNPs with CD susceptibility. MethodsOne hundred twelve CD patients and 164 healthy controls were recruited. Serum BAFF levels were determined using an enzyme-linked immunosorbent assay. Participants were genotyped for rs9514828, rs1041569 and rs2893321 SNPs. ResultsSerum BAFF concentration was elevated in CD patients (472.86 ± 223.60 pg/ml) compared with controls (128.16 ± 70.10 pg/ml) before treatment. Responders to IFX treatment had increased serum BAFF levels at baseline (610.03 ± 167.55 pg/ml) compared to non-responders (267.09 ± 107 pg/ml). In responders, BAFF concentration reduced after IFX administration, while increased in non-responders. The rs1041569, TA and AA genotypes frequencies, and the minor allele A were increased significantly in CD patients, indicating an association of the SNP with CD susceptibility. ConclusionsOur study suggests that BAFF could be a potential biomarker of CD, while SNP rs1041569 was associated with CD susceptibility.

Effects of BAFF Neutralization on Atherosclerosis Associated With Systemic Lupus Erythematosus.

Cardiovascular disease (CVD) is the leading cause of death in systemic lupus erythematosus (SLE). B cells play a key role in the pathogenesis of lupus, and anti-BAFF therapy has been approved for use in SLE. Since mature B cells also promote atherosclerosis, we undertook this study to evaluate, in a mouse model and in SLE patients, whether BAFF neutralization has an atheroprotective effect in SLE. The effect of BAFF on atherosclerosis associated with lupus was investigated in the atherosclerosis/lupus-prone apolipoprotein E-knockout D227K mouse model and in a cohort of SLE patients. Mice were treated with a blocking anti-BAFF monoclonal antibody (mAb), while fed a standard chow diet. Carotid plaque and carotid intima-media thickness were assessed by ultrasound at baseline and during follow-up in SLE patients who were asymptomatic for CVD. Anti-BAFF mAb in ApoE-/- D227K mice induced B cell depletion, efficiently treated lupus, and improved atherosclerosis lesions (21% decrease; P = 0.007) in mice with low plasma cholesterol levels but worsened the lesions (17% increase; P = 0.06) in mice with high cholesterol levels. The atheroprotective effect of the BAFF-BAFF receptor signaling inhibition on B cells was counterbalanced by the proatherogenic effect of the BAFF-TACI signaling inhibition on macrophages. In SLE patients, blood BAFF levels were associated with subclinical atherosclerosis (r = 0.26, P = 0.03). Anti-BAFF mAb treatment had a differential effect on the intima-media thickness progression in SLE patients depending on body mass index. Depending on the balance between lipid-induced and B cell-induced proatherogenic conditions, anti-BAFF could be detrimental or beneficial, respectively, to atherosclerosis development in SLE.

B cell activating factor (BAFF): Structure, functions, autoimmunity and clinical implications in Systemic Lupus Erythematosus (SLE).

The B cell activating factor (BAFF), or B lymphocyte stimulator (BLyS), is a B cell survival factor which supports autoreactive B cells and prevents their deletion. BAFF expression is closely linked with autoimmunity and is enhanced by genetic alterations and viral infections. Furthermore, BAFF seems to be involved in adipogenesis, atherosclerosis, neuro-inflammatory processes and ischemia reperfusion (I/R) injury. BAFF is commonly overexpressed in Systemic Lupus Erythematosus (SLE) and strongly involved in the pathogenesis of the disease. The relationship between BAFF levels, disease activity and damage accrual in SLE is controversial, but growing evidence is emerging on its role in renal involvement. Belimumab, a biologic BAFF inhibitor, has been the first biologic agent licensed for SLE therapy so far. As Rituximab (RTX) has been shown to increase BAFF levels following B cell depletion, the combination therapy of RTX plus belimumab (being evaluated in two RCT) seems to be a valuable option for several clinical scenarios. In this review we will highlight the growing body of evidence of immune and non-immune related BAFF expression in experimental and clinical settings.