BLyS and April serum levels in patients with autoimmune thyroid diseases

Pre- and Post-treatment Serum BAFF Levels and BAFF Gene Polymorphisms in Patients with Graves' Disease

BACKGROUND

B cell activating factor (BAFF), a crucial factor for B cell survival and differentiation, has been linked to several autoimmune conditions. The aim of this study was to evaluate the association of BAFF gene's polymorphisms with its serum levels and to assess their effect on Graves' disease (GD) susceptibility and presentation.

METHODS

Sixty-two GD patients and 152 healthy controls have been enrolled to investigate BAFF rs9514827 (-2841 T/C), rs1041569 (-2701 T/A) and rs9514828 (-871 C/T) gene's polymorphism by PCR-RFLP and serum BAFF level's kinetics under medical treatment by ELISA.

RESULTS

Median serum BAFF level at baseline was significantly higher in GD patients (841.7 pg/ml [685.23-1058.32]) comparatively to controls (495.75 pg/ml [383.17-595.7]), p = 7.29 E-25. A ROC curve was used to assess BAFF performances in GD diagnosis and revealed an AUC of 94.9% [0.919-0.979], p = 7.29 E-25. At a cutoff value of 654.9 pg/ml of BAFF at baseline, the sensitivity and the specificity were, respectively, 83.9% and 90.8%. BAFF level was significantly increased in smoking patients (1079.55 pg/ml [875.35-1203]) comparatively to nonsmokers (746.95 pg/ml [643.2-915.7]), p = 3.1 E-5. While -2841 T/C and -2701 T/A genotypes and alleles frequencies were similar between patients and controls, the -871*T allele was significantly more prevalent in patients (0.613) than in controls (0.477); p = .01, OR [95% CI] = 1.73 [1.13-2.65]. The three studied polymorphisms were not associated with serum BAFF level at baseline.

CONCLUSION

Serum BAFF level is significantly increased in GD especially in smoking patients. rs9514828 - 871*T allele might be a susceptibility variant for GD.

High triiodothyronine levels induce myocardial hypertrophy via BAFF overexpression

Activated B cells contribute to heart diseases, and inhibition of B‐cell activating factor (BAFF) expression is an effective therapeutic target for heart diseases. Whether activated B cells participate in the development and progression of hyperthyroid heart disease, and what induces B cells activation in hyperthyroidism are unknown. The present study aimed to determine the roles of BAFF overexpression induced by high concentrations of triiodothyronine (T3) in the pathogenesis of hyperthyroid heart disease. Female C57BL/6J mice were subcutaneously injected with T3 for 6 weeks, and BAFF expression was inhibited using shRNA. Protein and mRNA expression of BAFF in mouse heart tissues evaluated via immunohistochemistry, western blotting and polymerase chain reaction (PCR). Proportions of B cells in mouse cardiac tissue lymphocytes were quantified via flow cytometry. Morphology and left ventricle function were assessed using pathological sections and echocardiography, respectively. Here, we demonstrate that compared with the control group, the proportion of myocardial B cells was larger in the T3 group; immunohistochemistry, western blotting and PCR analyses revealed increased protein and mRNA expression levels of TNF‐α and BAFF in heart tissues of the T3 group. Compared with the normal controls group, in the T3 group, the diameter of myocardial cells and some echocardiographic values significantly increased and hypertrophy and structural disorder were noticeable. Our results revealed that elevated levels of circulating T3 can promote the expression of BAFF in myocardial cells and can lead to B‐cell activation, an elevated inflammatory response and ventricular remodelling.

Cytokines in the Immune Microenvironment Change the Glycosylation of IgG by Regulating Intracellular Glycosyltransferases

Background

Changes in IgG glycosylation, as a novel pathological feature, are observed in various autoimmune diseases (AIDs). The glycosylation patterns of IgG play a critical role in regulating the biological function and stability of IgG involved in the pathophysiology of many AIDs. However, the intracellular regulatory mechanisms underlying the effects of disturbances in various cytokines on IgG glycosylation are poorly understood. Thus, we investigated the regulatory effects of elevated cytokines in AIDs on intracellular IgG glycosylation within B cells.

Methods

First, we established a controlled primary culture system in vitro to differentiate human CD19+ B cells into antibody-secreting cells (ASCs). Then, the IgG concentrations in the supernatants were measured by enzyme-linked immunoassay (ELISA) under IFN-γ, TNF-α, IL-21, IL-17A, BAFF, or APRIL stimulation. Next, the glycosylation levels of IgG under different stimuli were compared via a lectin microarray. The fine carbohydrate structures of IgG were confirmed by matrix-assisted laser desorption/ionization-quadrupole ion trap-time of flight-mass spectrometry (MALDI-TOF-MS). Finally, the expression of glycosyltransferases and glycosidases in B cells under stimulation with several cytokines was detected by real-time PCR and western blotting.

Results

We found that cytokines significantly promoted IgG production in vitro and led to considerably different IgG glycan patterns. Specifically, the results of lectin microarray showed the galactose level of IgG was increased by IFN-γ stimulation (p<0.05), and the sialylation of IgG was increased by IL-21 and IL-17A (p<0.05). The MALDI-TOF-MS data showed that the frequency of agalactosylation was decreased by IFN-γ with the increased frequency of mono-galactosylation and decreased frequency of digalactosylation, accompanied by upregulation of β-1,4-galactosyltransferase 1. Both frequencies of mono-sialylated and disialylated N-glycans were increased by IL-21 and IL-17A with decreased frequency of asialylation, and the expression of β-galactoside α-2,6-sialyltransferase 1 was upregulated by IL-21 and IL-17A.

Conclusion

Abnormally elevated cytokines in the microenvironment regulates IgG glycan patterns by regulating intracellular glycosyltransferases in human B cells.

Possible interplay between estrogen and the BAFF may modify thyroid activity in Graves' disease

A link between sex hormones and B-cell activating factor (BAFF), a crucial immunoregulator of autoimmune thyroid disease (AITD), may exist. The study aimed to elucidate the role of estrogen (E2) in regulating BAFF in Graves' disease (GD). In clinical samples, serum BAFF levels were higher in women than in men in both the GD and control groups. serum BAFF levels were associated with thyroid-stimulating hormone receptor antibody levels and thyroid function only in women and not in men. BAFF transcripts in peripheral blood mononuclear cells were higher in women with GD than those in the control group. Among GD patients with the AA genotype of rs2893321, women had higher BAFF transcripts and protein levels than men. In the progression of a spontaneous autoimmune thyroiditis (SAT) murine model, NOD.H-2h4, serum free thyroxine and BAFF levels were higher in female than in male mice. Moreover, exogenous E2 treatment increased serum BAFF levels in male SAT mice. Meanwhile, female SAT mice exhibited higher thyroid BAFF transcripts levels than either the E2-treated or untreated male SAT mouse groups. Our results showed that E2 might be implicated in modulating BAFF expression, and support a possible mechanism for the higher incidence of AITD in women.

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

BACKGROUND

B 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.

METHODS

Fifty-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.

RESULTS

Serum 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).

CONCLUSIONS

Altered 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.

B cells in Graves' Orbitopathy: more than just a source of antibodies?

B cells have multiple actions on different phases of an immune reaction, mainly resulting in B and T cell-interaction (help), production of cytokines, regulation of dendritic cells and downregulation of regulatory B cells. The effectiveness of B cell depletion therapy is probably due to blockade of the antigen-presenting function of B cells, occurring very early in the setting of autoimmune reactions. B cells undergo a maturation process from stem cells during which the CD 20 antigen, which is the target of rituximab (RTX), is expressed from the stage of pre-B cells to mature and memory B cells, but not on plasma cells. During the maturation process, the cytokine B cell stimulating factor (BAFF) induces maturation of B cells and expansion of clones to produce plasma cells and eventually antibodies. The effect of RTX in GO is rather rapid, with significant improvement of the disease already 4-6 weeks after the first RTX infusion. Based on the evidence of significant lymphocytic infiltration in the orbits of patients with active GO, it is reasonable to postulate that RTX may cause depletion of B cells and block their antigen-presenting cell mechanism. Since it has been reported that serum BAFF concentrations are elevated in hyperthyroid GD patients and that BAFF is expressed on the thyrocytes of patients with either autoimmune disease or nodular goiter, the hypothesis that belimumab, an anti-BAFF monoclonal antibody, may be effective in patients with active GO his currently being tested in a randomized controlled trial.

Loss of CXCR3 expression on memory B cells in individuals with long-standing type 1 diabetes

AIMS/HYPOTHESIS

Islet-specific autoantibodies can predict the development of type 1 diabetes. However, it remains unclear if B cells, per se, contribute to the causal pancreatic immunopathology. We aimed to identify phenotypic signatures of disease progression among naive and memory B cell subsets in the peripheral blood of individuals with type 1 diabetes.

METHODS

A total of 69 participants were recruited across two separate cohorts, one for discovery purposes and the other for validation purposes. Each cohort comprised two groups of individuals with type 1 diabetes (one with newly diagnosed type 1 diabetes and the other with long-standing type 1 diabetes) and one group of age- and sex-matched healthy donors. The phenotypic characteristics of circulating naive and memory B cells were investigated using polychromatic flow cytometry, and serum concentrations of various chemokines and cytokines were measured using immunoassays.

RESULTS

A disease-linked phenotype was detected in individuals with long-standing type 1 diabetes, characterised by reduced C-X-C motif chemokine receptor 3 (CXCR3) expression on switched (CD27⁺IgD^-) and unswitched (CD27^intermediateIgD⁺) memory B cells. These changes were associated with raised serum concentrations of B cell activating factor and of the CXCR3 ligands, chemokine (C-X-C motif) ligand (CXCL)10 and CXCL11. A concomitant reduction in CXCR3 expression was also identified on T cells.

CONCLUSIONS/INTERPRETATION

Our data reveal a statistically robust set of abnormalities that indicate an association between type 1 diabetes and long-term dysregulation of a chemokine ligand/receptor system that controls B cell migration.

Is Graves' disease a primary immunodeficiency? New immunological perspectives on an endocrine disease

BACKGROUND

Uncertainty about factors influencing the susceptibility and triggers for Graves' disease persists, along with a wide variation in the response to anti-thyroid drugs, currently at approximately 50% of non-responders. The aim of this narrative review is to summarize immunological concepts, with a combined endocrine and immunological perspective, to highlight potential new areas of research.

MAIN TEXT

Relevant studies were identified through a systematic literature search using the PubMed and EMBASE databases in March 2016. No cut-offs regarding dates were imposed. We used the terms "Graves' Disease" or "Basedow" or "thyrotoxicosis" together with the terms "etiology", "pathophysiology", "immunodeficiency", "causality", and "autoimmunity". The terms "orbitopathy", "ophthalmopathy", and "amiodarone" were excluded. Articles in English, French, German, Croatian, Spanish, and Italian were eligible for inclusion.

CONCLUSIONS

While concepts such as the impact of iodine, smoking, human leucocyte antigen, infections, and ethnicity are established, new ideas have emerged. Pertaining evidence suggests the involvement of autoimmunity and immunodeficiency in the pathophysiology of Graves' disease. Recent studies point to specific immunological mechanisms triggering the onset of disease, which may also serve as targets for more specific therapies.

Serum BAFF and thyroid autoantibodies in autoimmune thyroid disease

BACKGROUND

This study investigated the association of serum B-lymphocyte activating factor (BAFF) levels with autoimmune thyroid disease (AITD) in a Chinese population.

MATERIALS AND METHODS

We enrolled 221 patients with AITD [170 patients with Graves' disease (GD), 51 patients with Hashimoto's thyroiditis (HT)], and 124 healthy controls. Serum BAFF levels, thyroid function and thyroid autoantibody (TAb) levels, including of thyroid-stimulating hormone receptor antibody (TSHRAb), anti-thyroid peroxidase antibody (Anti-TPO Ab), and antithyroglobulin antibody (ATA), were measured at baseline.

RESULTS

Serum BAFF levels were higher in the GD, HT, and AITD groups than in the control group. Significant correlations were observed between BAFF and TSHRAb levels (r=0.238, p=0.018), between BAFF and Anti-TPO Ab levels (p=0.038), and between BAFF and ATA titers (p=0.025) in women but not in men. In addition, serum BAFF levels were significantly associated with free thyroxine (r=0.430, p=0.004) and TSHRAb (r=0.495, p=0.001) levels in women with active GD but not in those with inactive GD.

CONCLUSIONS

Serum BAFF levels are increased in GD, HT, and AITD. The correlation between serum BAFF and TAb levels exhibits a dimorphic pattern, particularly in active GD.

THERAPY OF ENDOCRINE DISEASE: Endocrine dilemma: management of Graves' orbitopathy

Management of Graves' orbitopathy (GO) must be based on the correct assessment of activity and severity of the disease. Activity is usually assessed with the Clinical Activity Score, whereas severity is classified according to a European Group On Graves' Orbitopathy (EUGOGO) consensus statement as mild, moderate-to-severe, and sight-threatening. Myopathic and chronic congestive forms are uncommon clinical presentations of GO. Restoration and maintenance of stable euthyroidism are recommended in the presence of GO.In moderate-to-severe disease, steroids have been widely employed and have shown to possess an anti-inflammatory activity, but about 20-30% of patients are not responsive and present recurrence. Some novel immunosuppressors have already been employed in clinical studies and have shown interesting results, although the lack of randomized and controlled trials suggests caution for their use in clinical practice. Potential targets for therapy in GO are the thyroid-stimulating hormone and the insulin-like growth factor 1 receptor on the fibroblasts, inflammatory cytokines, B and T cells, and the PIK3/mTORC1 signaling cascades for adipogenesis. A recent open study has shown that tocilizumab, an anti-sIL-6R antibody, inactivates GO. Consistent reports on the efficacy of rituximab have recently been challenged by randomized controlled trials.As the main goal of treatment is the well-being of the patient, the therapeutic strategy should be addressed to better suit the patient needs, more than improving one or more biological parameters. The increasing availability of new therapies will expand the therapeutic options for GO patients and allow the clinician to really personalize the treatment to better suit the patients' personal needs.

Analysis of Associations of Human BAFF Gene Polymorphisms with Autoimmune Thyroid Diseases

Background

The B-lymphocyte-activating factor (BAFF) is associated with B-cell functions, and gene polymorphisms of the BAFF have been linked to autoimmune diseases (AIDs). In this study, we explored possible associations of two BAFF single-nucleotide polymorphisms (SNPs), rs1041569 and rs2893321, with autoimmune thyroid diseases (AITDs) in an ethnic Chinese population.

Material and Methods

In total, 319 Graves’ disease (GD), 83 Hashimoto’s thyroiditis (HT) patients, and 369 healthy controls were enrolled. Polymerase chain reaction-restriction fragment length polymorphism and direct sequencing were used to genotype rs2893321 and rs1041569.

Results

There was a significant difference in frequencies of the G allele and AG+GG genotype of rs2893321 between the GD and control groups (p = 0.013, odds ratio (OR) = 0.76, and p = 0.017, OR = 0.68, respectively) and between the AITD and control groups (p = 0.009, OR = 0.76, and, p = 0.014, OR = 0.69, respectively). The AA genotype of rs2893321 was associated with low titers of the thyroid-stimulating hormone receptor antibody (TSHRAb) (p = 0.015) in males but not in females. The AA genotype of rs2893321 was associated with the presence of two different types of thyroid autoantibody (TAb) (TSHRAb and Hashimoto’s autoantibody (anti-thyroglobulin or anti-microsomal antibody)) in females and with that of one type in males.

Conclusions

rs2893321 may be a susceptible genetic variant for the development of GD and AITDs. Associations of rs2893321 with susceptibility to GD and AITDs and the correlation between rs2893321 and TAb exhibit a dimorphic pattern. Additional studies with larger sample sizes are required to confirm our findings.

Decreased Circulating Levels of APRIL: Questioning Its Role in Diabetes

Diabetes mellitus is a chronic disease that affects over 382 million people worldwide. Type-1 Diabetes (T1D) is classified as an autoimmune disease that results from pancreatic β-cell destruction and insulin deficiency. Type-2 Diabetes (T2D) is characterized principally by insulin resistance in target tissues followed by decreased insulin production due to β-cell failure. It is challenging to identify immunological markers such as inflammatory molecules that are triggered in response to changes during the pathogenesis of diabetes. APRIL is an important member of the TNF family and has been linked to chronic inflammatory processes of various diseases since its discovery in 1998. Therefore, this study aimed to evaluate APRIL serum levels in T1D and T2D. For this, we used the ELISA assay to measure serum APRIL levels of 33 T1D and 30 T2D patients, and non-diabetic subjects as control group. Our data showed a decrease in serum APRIL levels in T1D patients when compared with healthy individuals. The same pattern was observed in the group of T2D patients when compared with the control. The decrease of serum APRIL levels in diabetic patients suggests that this cytokine has a role in T1D and T2D. Diabetes is already considered as an inflammatory condition with different cytokines being implicated in its physiopathology. Our data suggest that APRIL can be considered as a potential modulating cytokine in the inflammatory process of diabetes.

B Cell Activating Factor (BAFF) and BAFF Receptor Expression in Autoimmune and Nonautoimmune Thyroid Diseases

BACKGROUND

The B cell activating factor (BAFF) is a member of the tumor necrosis factor family, which controls the survival/proliferation of B cells and is involved in the pathogenesis of a number of autoimmune diseases. The objective of the present study was to investigate the expression of BAFF and BAFF receptor (BAFF-R) in the thyroid tissue of patients affected with autoimmune thyroid disorders (AITD) or multinodular goiter (MNG) compared with those with normal thyroids.

METHODS

Immunohistochemistry was performed using a panel of antibodies against BAFF, BAFF-R, CD3, CD4, CD8, CD20, CD34, CD79a, CD1a, CD68, and CD163 on the thyroid sections of 27 patients affected with Graves' disease (GD), 23 with Hashimoto's thyroiditis (HT), 16 with nontoxic nodular goiter (NTG), and 15 with toxic nodular goiter (TG), submitted to total thyroidectomy between 2000 and 2011.

RESULTS

The overall BAFF-R expression in thyrocytes was weak and not different in AITD and MNG. Conversely, a stronger BAFF expression was observed in MNG compared with AITD. BAFF and BAFF-R expression in the infiltrating lymphocytes was higher in AITD compared with MNG. Interestingly, in lymphocytes of follicular-like structures observed in HT, BAFF and BAFF-R were localized in the germinal center or in the mantle, respectively.

CONCLUSIONS

This study shows that BAFF and BAFF-R are expressed in the thyrocytes derived from patients with either AITD or MNG, in addition to the expected expression of BAFF and its receptor in the infiltrating immune cells of GD and HT. These findings suggest a possible involvement of BAFF and its receptors in the pathophysiology of AITD.

Serum sAPRIL: a potential tumor-associated biomarker to colorectal cancer

OBJECTIVE

The purpose of our study was to investigate the serum levels of soluble a-proliferation-inducing ligand (sAPRIL) in patients with colorectal cancer (CRC), benign intestinal disease and healthy volunteers and explore the potential possibility of sAPRIL severing as a CRC biomarker.

METHODS

Our investigation was conducted on 35 blood samples obtained from CRC patients, 32 blood samples from patients with benign intestinal diseases and 31 blood samples from healthy volunteers. The sAPRIL concentrations were examined by an enzyme-linked immunosorbent assay (ELISA) and data were analyzed with non-parametric Mann-Whitney U-test and X²-test. The correlation relationship between sAPRIL and CEA, as well as sAPRIL and CA19-9 was assessed by non-parametric Spearmen's correlation test, respectively.

RESULTS

The median value of sAPRIL in the malignant group was 10.43 ng/mL, compared with those of the benign group (4.89 ng/mL) and control group (3.30 ng/mL), respectively, which had an obvious significance (P<0.0003). Area under the receiver-operating characteristic (ROC) curve for sAPRIL was 0.854 (95% CI, 0.776-0.933). The optimal cut-off level of sAPRIL was 5.49 ng/mL. Serum sAPRIL had a positive correlation with CEA (r=0.637, P=0.000) and CA19-9 (r=0.357, P=0.008) in 35 patients with colorectal cancer. sAPRIL showed higher sensitivity (82.9%) than those of CEA (74.3%) and CA19-9 (65.7%) in CRC, respectively.

CONCLUSION

The results indicated that serum sAPRIL, as a potential biomarker, had a positive diagnostic value for colorectal cancer.

Intrinsic molecular factors cause aberrant expansion of the splenic marginal zone B cell population in nonobese diabetic mice

Marginal zone (MZ) B cells are an innate-like population that oscillates between MZ and follicular areas of the splenic white pulp. Differentiation of B cells into the MZ subset is governed by BCR signal strength and specificity, NF-κB activation through the B cell-activating factor belonging to the TNF family (BAFF) receptor, Notch2 signaling, and migration signals mediated by chemokine, integrin, and sphingosine-1-phosphate receptors. An imbalance in splenic B cell development resulting in expansion of the MZ subset has been associated with autoimmune pathogenesis in various murine models. One example is the NOD inbred mouse strain, in which MZ B cell expansion has been linked to development of type 1 diabetes and Sjögren's syndrome. However, the cause of MZ B cell expansion in this strain remains poorly understood. We have determined that increased MZ B cell development in NOD mice is independent of T cell autoimmunity, BCR specificity, BCR signal strength, and increased exposure to BAFF. Rather, mixed bone marrow chimeras showed that the factor(s) responsible for expansion of the NOD MZ subset is B cell intrinsic. Analysis of microarray expression data indicated that NOD MZ and precursor transitional 2-MZ subsets were particularly dysregulated for genes controlling cellular trafficking, including Apoe, Ccbp2, Cxcr7, Lgals1, Pla2g7, Rgs13, S1pr3, Spn, Bid, Cd55, Prf1, and Tlr3. Furthermore, these B cell subsets exhibited an increased steady state dwell time within splenic MZ areas. Our data therefore reveal that precursors of mature B cells in NOD mice exhibit an altered migration set point, allowing increased occupation of the MZ, a niche favoring MZ B cell differentiation.

Primary biliary cirrhosis and Sjögren's syndrome: autoimmune epithelitis

Primary biliary cirrhosis (PBC) has been often coined a model autoimmune disease based on the homogeneity amongst patients, the frequency and similarity of antimitochondrial antibodies, including the highly directed immune response to pyruvate dehydrogenase (PDC-E2). A significant number of patients with PBC suffer from sicca and amongst these, there are patients who also have classic Sjögren's syndrome. Indeed, both PBC and Sjögren's syndrome are characterized by inflammation of target epithelial elements. Both diseases can be considered on the basis of a number of other related clinical aspects, including proposed unique apoptotic features of the target tissue, the role of secretory IgA, and the frequency with which both diseases overlap with each other. Indeed, PBC may be considered a Sjögren's syndrome of the liver, whereas Sjögren's syndrome can be equally discussed as PBC of the salivary glands. Dissection of the genetic predispositions for both diseases and especially the molecular basis of effector mechanisms, will become critical elements in developing new therapies.

Autoimmunity in 2010

There is now growing evidence that autoimmunity is the common trait connecting multiple clinical phenotypes albeit differences in tissue specificity, pathogenetic mechanisms, and therapeutic approaches cannot be overlooked. Over the past years we witnessed a constant growth of the number of publications related to autoimmune diseases in peer-reviewed journals of the immunology area. Original data referred to factors from common injury pathways (i.e. T helper 17 cells, serum autoantibodies, or vitamin D) and specific diseases such as multiple sclerosis, systemic lupus erythematosus, and rheumatoid arthritis. As an example, the issue of a latitudinal gradient in the prevalence and incidence rates has been proposed for all autoimmune diseases and was recently coined as geoepidemiology to suggest new environmental triggers for tolerance breakdown. The present article is aimed at reviewing the articles that were published over the past year in the major autoimmunity and immunology journals.

Serum APRIL, a potential tumor marker in pancreatic cancer

BACKGROUND

A proliferation-inducing ligand (APRIL) is a newly-found member in the tumor necrosis factor (TNF) superfamily. Our previous studies have already confirmed that APRIL is overexpressed in pancreatic cancer tumors, however, it is not expressed or has a weak expression in normal pancreatic gland tissues. Furthermore, there is no report on serum APRIL in patients with pancreatic diseases. Herein, in order to explore the clinical implication of serum APRIL in patients with pancreatic cancer, serum APRIL, together with carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9, was examined.

METHODS

Serum APRIL was tested by ELISA in patients with pancreatic cancer. Meanwhile, two other conventional serum tumor markers, CEA and CA19-9, were measured by Elecsys 2010 Chemistry Analyzer.

RESULTS

Serum APRIL increased in patients with pancreatic cancer, which proved a positive correlation with CEA and CA19-9. When the diagnosis of benign or malignant condition was examined by one tumor marker, the sensitivity of APRIL alone (70.1%) was greater than that of CEA alone (56.7%), and the specificity of APRIL alone (85.5%) was higher than that of CA19-9 alone (83.6%). When examined by a combination of two markers, the sensitivity of the combination of APRIL and CA19-9 was the highest (88.1%), as it was compared with that of APRIL alone, CEA alone and APRIL+CEA, p<0.05. In addition, serum APRIL also correlated with the tumor stage and postoperative survival in patients with pancreatic cancer.

CONCLUSIONS

Our results indicate that serum APRIL, as a potential biomarker, has a positive diagnosis and prognosis value for pancreatic cancer. Moreover, the combination assay of APRIL and CA19-9 is highly sensitive to pancreatic cancer.

Bioassays for TSH-receptor autoantibodies: an update

Immunoglobulins in patients with Graves' disease (GD) that modulate the thyroid stimulating hormone receptor (TSH-R) do so via stimulating cAMP dependent signals (TSI), blocking TSH or inhibition of TSH-receptor activation (TBI) or inducing apoptotic signals. These functional immunoglobulins represent powerful biomarkers of anti-self reactivity in the thyroid and systemic tissues that harbor TSH-R expressing target cells. TSI on thyrocytes induce hyperthyroidism, and TSI on TSH-R fibroblasts of orbital muscles, skin and heart provoke the release of cytokines and antigen-specific T-cell responses leading to systemic inflammation. Bioassays of anti-TSH-R autoantibodies provide decisive information on GD activity. This review examines the past and present bioassays in GD. The critical goal of cell-based anti-TSH-R autoantibody bioassays, to identify the pathogenic immunoglobulins in GD under robust and standardized conditions suitable for routine clinical laboratory practice, is discussed.

Clinical review about TRAb assay's history

Commercial assays to measure thyroid stimulating hormone (TSH) receptor (TSHR) autoantibodies (TRAb) have been available for the serological diagnosis of autoimmune thyroid diseases (AITD) for several years. The widespread assessment of this parameter has identified Graves' disease (GD) as a common organ-specific autoimmune disease. Within the present article we aim to review immunobiological and epidemiological aspects as well as diagnostic methods available for the detection of TRAb. Over the last decade, TRAb detection in GD became more sensitive since TRAb assays were being largely improved by named research groups. Therefore, functional assay (fas) and diagnostic sensitivity of current TRAb assays will be discussed. Within the second part of this review we will focus on clinical applications of TRAb measurement for outcome prediction of GD as well as the importance of this method to distinguish GD from other AITD.