Autoantigen characterization in the lower esophageal sphincter muscle of patients with achalasia

BACKGROUND

Serum anti-myenteric autoantibodies define autoimmune achalasia and tissue MMP-9 activity may locally process autoantigenic proteins in the muscle of the lower esophageal sphincter (LES) of achalasia patients.

METHODS

Biopsies of the LES muscle from 36 achalasia patients, 6 esophagogastric junction outflow obstruction (EGJOO) patients, and 16 transplant donors (TD) were compared in a blind cross-sectional study. Histological characteristics such as inflammation, fibrosis, presence of ganglion cells, cells of Cajal, GAD65, PNMA2, S-100, P substance, and MMP-9 proteoforms in tissue were assessed by H&E and Picrosirius Red staining and immunohistochemistry analysis. Anti-neuronal antibodies, onconeural antigens, recoverin, SOX-1, titin, zic4, GAD65, and Tr were evaluated by immunoblot/line assay.

KEY RESULTS

Tissue of achalasia patients had heterogeneous inflammatory infiltrates with fibrosis and contrasting higher levels of activated MMP-9, as compared with EGJOO and TD. Moreover, lower ganglion cell percentages and cell of Cajal percentages were determined in esophageal tissues of achalasia patients versus TD. The tissues of achalasia versus EGJOO patients had higher GAD65 and PNMA2 protein expression. Unexpectedly, these proteins were absent in TD tissue. S-100 and P substance had similar expression levels in tissues of achalasia patients versus TD and EGJOO. Most of the achalasia sera had anti-GAD65 (83%) and anti-PNMA2 (90%) autoantibodies versus EGJOO (17% and 33%, respectively) and healthy volunteers (10% and 0%, respectively).

CONCLUSIONS AND INFERENCES

Tissue-specific ectopic expression of GAD65 and PNMA/Ta2 and active MMP-9, associated with the presence of specific autoantibodies directed against these proteins, might participate in the pathophysiology of achalasia triggering and/or perpetuating autoimmune disease.

Cytokines secretion from human mesenchymal stem cells induced by bovine bone matrix

BACKGROUND

Bovine bone matrix is a natural material that has been used in the treatment of bone lesions. In this study, bovine bone matrix Nukbone® (NKB) was investigated due its osteoconductive and osteoinductive properties. This biomaterial induces CBFA-1 activation and osteogenic differentiation, although the cytokines involved in these processes is still unknown.

OBJECTIVE

The aim of this work was to determine the influence of NKB on the pro-osteoblastic and anti-osteoblastic cytokines secretion from human mesenchymal stem cells (hMSCs).

METHODS

The hMSCs were cultured onto NKB and cytokines IL-2, IL-4, IL-6, IL-10, IL-12, IFN-γ and TNF-α were analized at 0-14 days by immunoassay. In addition, hemocompatibility of NKB and characterization of hMSCs were evaluated.

RESULTS

NKB induces an increase on pro-osteoblastic cytokine secretion IL-4 and a decrease on anti-osteoblastic cytokine IL-6 secretion, at days 7 and 14 of cell culture. Interestingly, there was no statistical difference between secretion profiles of others cytokines analized.

CONCLUSIONS

The up-regulation of IL-4 and down-regulation of IL-6, and the secretion profiles of other cytokines examined in this work, are findings that will contribute to the understanding of the role of NKB, and similar biomaterials, in bone homeostasis and in the osteoblastic differentiation of hMSCs.

Esophagogastric junction outflow obstruction: Characterization of a new entity? Clinical, manometric, and neuroimmunological description

OBJECTIVE

To determine the differences between clinical, manometric, and neuroimmunological profile of esophagogastric junction outflow obstruction (EGJOO) and achalasia patients.

METHODS

Seven EGJOO and 27 achalasia patients were enrolled in a blind cross-sectional study. Peripheral blood (PB) of 10 healthy donors and 10 lower esophageal sphincter (LES) muscle biopsies from organ transplant donors were included as controls. The presence of ganglion cells, cells of Cajal, Th22/Th7/Th2/Th1/Tregs/Bregs/pDCregs in tissue, and PB was assessed by immunohistochemistry and flow cytometry. Serum concentration of IL-22/IL-17A/IL-17F/IL-4/IFN-γ/IL-1β/IL-6/IL-23/IL-33/TNF-α/IL-10 was determined using bioplex plates. ANAs and antineuronal antibodies were evaluated by immunofluorescence and Western blot.

KEY RESULTS

EGJOO and achalasia patients had lower ganglion cells and cells of Cajal percentage vs. controls, while fibrosis was present only in achalasia patients. EGJOO and controls had lower cell percentage of Th22/Th17/Th2 vs. achalasia. EGJOO tissue had lower Th1/Treg cell number vs. achalasia, but higher levels vs. control group. Bregs and pDCregs percentage was higher in EGJOO vs. control group. Percentage of PB subpopulations in EGJOO was not significantly different from control group. Serum cytokine levels were higher for IL-1β/IL-6/TNF-α, while IL-17A levels were lower in EGJOO vs. achalasia and control group. EGJOO group was negative for ANAs, while in achalasia group, 54% were positive. GAD65 and PNMa/Ta2 antibodies were present in achalasia, whereas Yo and recoverin were positive in EGJOO group.

CONCLUSIONS AND INFERENCES

Although EGJOO shares some clinical characteristics with achalasia, the neuroimmunological profile is completely different, suggesting that EGJOO might be a different entity.

The Transcription Factor SCX is a Potential Serum Biomarker of Fibrotic Diseases

Fibrosing diseases are causes of morbidity and mortality around the world, and they are characterized by excessive extracellular matrix (ECM) accumulation. The bHLH transcription factor scleraxis (SCX) regulates the synthesis of ECM proteins in heart fibrosis. SCX expression was evaluated in lung fibroblasts and tissue derived from fibrotic disease patients and healthy controls. We also measured SCX in sera from 57 healthy controls, and 56 Idiopathic Pulmonary Fibrosis (IPF), 40 Hypersensitivity Pneumonitis (HP), and 100 Systemic Sclerosis (SSc) patients. We report high SCX expression in fibroblasts and tissue from IPF patients versus controls. High SCX-serum levels were observed in IPF (0.663 ± 0.559 ng/mL, p < 0.01) and SSc (0.611 ± 0.296 ng/mL, p < 0.001), versus controls (0.351 ± 0.207 ng/mL) and HP (0.323 ± 0.323 ng/mL). Serum levels of the SCX heterodimerization partner, TCF3, did not associate with fibrotic illness. IPF patients with severely affected respiratory capacities and late-stage SSc patients presenting anti-topoisomerase I antibodies and interstitial lung disease showed the highest SCX-serum levels. SCX gain-of-function induced the expression of alpha-smooth muscle actin (α-SMA/ACTA2) in fibroblasts when co-overexpressed with TCF3. As late and severe stages of the fibrotic processes correlated with high circulating SCX, we postulate it as a candidate biomarker of fibrosis and a potential therapeutic target.

Omega-3 and omega-6 fatty acids in primary Sjögren's syndrome: clinical meaning and association with inflammation

OBJECTIVES

Lipid mediators derived from polyunsaturated fatty acids (FA), have been related to inflammation and immune response regulation. Herein we evaluated the intake and serum levels of ω-3 and ω-6 FA among patients with primary Sjögren's syndrome (pSS), and correlated with ocular/oral sicca symptoms, disease activity and a panel of chemokines/cytokines.

METHODS

We included 108 patients and 100 controls. Dietary information was obtained from a food questionnaire of one-day reminder and processed using a nutritional software. Among the SS group, we measured serum ω-3 (α-linolenic acid [α-LN], eicosapentaenoic acid [EPA], docosahexaenoic acid [DHA]) and ω-6 (linoleic acid [LA], arachidonic acid [AA]) by gas chromatography flame ionization. We scored the ESSDAI, ESPRI, Schirmer-I test and NSWSF. In a subsample, we assessed the OSDI, ophthalmologic staining scores and measured CXCL8, CXCL10, CCL2, IL-22 and IL-21 in saliva, and CXCL8, CXCL10, CCL2 and CXCL9 in tears by Luminometry.

RESULTS

ω-3 and ω-6 intake was lower in SS patients than controls, and did not correlate with serum levels. We found a negative correlation between α-LN and the OSDI and ESSDAI, as well as DHA and ESSDAI. In tears, AA positively correlated with CXCL9, whereas in saliva, α-LN, DHA and the ω3 sum negatively correlated with CCL2. We observed a negative correlation between the ω6 sum and IL-21.

CONCLUSIONS

pSS patients had deficient omega intake. Lower ocular symptoms, ESSDAI scores and salivary CCL2 correlated with higher ω-3 levels, possible suggesting a role in chronic inflammation. Further studies are warranted to deepen in the knowledge of this association.

Triosephosphate isomerase, carbonic anhydrase, and creatinine kinase-brain isoform are possible antigen targets in patients with achalasia

BACKGROUND

Idiopathic achalasia is an uncommon esophageal motor disorder. The disease involves interaction between inflammatory and autoimmune responses. However, the antigens related to the disease are still unknown.

AIM

To identify the possible antigen targets in muscle biopsies from lower esophageal sphincter (LES) of achalasia patients.

METHODS

Esophageal biopsies of patients with type I and type II achalasia and esophagogastric junction outflow obstruction (EGJOO) were analyzed. Lower esophageal sphincter muscle biopsy from a Healthy organ Donor (HD) was included as control for two-dimensional gel electrophoresis. Immunoblotting of muscle from LES lysate with sera of type I, type II achalasia, or type III achalasia, sera of EGJOO and sera of healthy subjects (HS) was performed. The target proteins of the serum were identified by mass spectrometry Matrix-assited laser desorption/ionization time-of-flight (MALDI-TOF).

KEY RESULTS

The proteomic map of muscle from LES tissue lysates of type I, and type II achalasia, EGJOO, and HD were analyzed and divided into three important regions. We found a difference in the concentration of certain spots. Further, we observed the serum reactivity of type I achalasia and type II achalasia against 45 and 25 kDa bands of type I achalasia tissue. Serum of type III achalasia and EGJOO mainly recognized 25 kDa band. Bands correspond to triosephosphate isomerase (TPI) (25 kDa), carbonic anhydrase (CA) (25 kDa) and creatinine kinase-brain (CKB) isoform (45 kDa).

CONCLUSIONS AND INFERENCES

We identify three antigen targets, TPI, CA, and CKB isoform, which are recognized by sera from patients with achalasia.

α-enolase is an antigenic target in primary Sjögren's syndrome

OBJECTIVES

Although anti-cyclic citrullinated peptides antibodies are specific markers for rheumatoid arthritis (RA), they might be present in other diseases. Our aim was to assess the native or citrullinated antigens recognised by patients with primary Sjögren's syndrome (pSS) and to evaluate their association with clinical and serological features.

METHODS

In an initial screening, we assessed the serum reactivity of 12 patients with pSS against native or in vitro citrullinated antigens of HEp-2 cells by immunoblotting. We identified a 47kDa band, which was preferentially recognised and corresponded to α-enolase. Thus, levels of IgA and IgG anti-native and citrullinated α-enolase antibodies were measured in 50 pSS patients, 20 RA patients and 20 healthy subjects (HS) by ELISA.

RESULTS

We identified α-enolase as a predominant antigen recognised in pSS. These patients had higher levels of anti-citrullinated α-enolase IgG antibodies compared with RA or HS (p=0.003 and p<0.0001, respectively). Furthermore, there was an increase of IgG anti-citrullinated α-enolase vs IgG anti-non-citrullinated α-enolase antibodies in pSS patients (p=0.001), by contrast no difference was found in RA. The presence of IgA and IgG anti-non-citrullinated and anti-citrullinated α-enolase antibodies were not associated with any clinical manifestation whatsoever, including non-erosive arthritis among pSS, but an association of IgA anti-citrullinated α-enolase with anti-Ro/SSA antibodies was found.

CONCLUSIONS

We characterised α-enolase as a dominant antigen in lysates of HEp- 2 cells in pSS. Nevertheless, their precise role in pSS remains to be elucidated.

Prevalence and associations of anti-phosphatidylserine/prothrombin antibodies with clinical phenotypes in patients with primary antiphospholipid syndrome: aPS/PT antibodies in primary antiphospholipid syndrome

OBJECTIVE

The clinical significance of anti-phosphatidylserine/prothrombin (aPS/PT) in antiphospholipid syndrome (APS) is still controversial. We assessed the prevalence of aPS/PT antibodies, their association with other anti-phospholipid antibodies (aPL) and with different APS clinical phenotypes.

METHODS

We included 95 primary APS patients according to the Sydney classification criteria, and patients with thrombocytopenia and/or hemolytic anemia who also fulfilled the serological APS criteria. We tested aCL, anti-β2GP-I and aPS/PT antibodies (both IgG and IgM isotypes) and lupus anticoagulant (LA). We used χ2 test, Spearman's correlation coefficient, Mann-Whitney U test and logistic regression.

RESULTS

Seventy-seven percent of patients had thrombosis, 50% hematologic involvement and 25% obstetric events (non-exclusive groups). Twenty patients had only hematologic features. The prevalence of IgG and IgM aPS/PT antibodies was 61% and 60%, respectively. Patients with LA+ had a higher prevalence and higher titers of IgG and IgM aPS/PT antibodies. aPS/PT antibodies correlated with aPL antibodies including LA. IgG aPS/PT antibodies were associated with thrombosis (OR 8.6 [95% CI 2.13-33.8, p = 0.002]) and pure hematologic features (OR 0.2, CI 95% 0.05-0.97, p = 0.004). IgM anti-β2GP-I antibodies conferred high risk for both hematologic (OR 7.9, 95% CI 1.88-34.61, p = 0.006) and thrombotic involvement (OR 7.4, 95% CI 1.76-31.12, p = 0.006).

CONCLUSIONS

aPS/PT antibodies were highly prevalent and correlated with other aPL antibodies. IgG aPTS/PT conferred a high risk for thrombosis, but not for pure hematologic involvement. aPS/PT antibodies may be a useful serological tool in the diagnosis and phenotypic characterization of APS patients.

Autoimmune comorbidity in achalasia patients

BACKGROUND AND AIM

Idiopathic achalasia is a rare esophageal motor disorder. The disease state manifests local and systemic inflammation, and it appears that an autoimmune component and specific autoantibodies participate in the pathogenesis. The study aims to determine the prevalence of autoimmune and chronic inflammatory diseases in patients with achalasia and compare the results with those from patients with gastroesophageal reflux disease (GERD).

METHODS

It was a cross-sectional and included 114 patients with idiopathic achalasia and 114 age-matched and sex-matched control patients with GERD. Data on the presence of autoimmune and inflammatory diseases, the time of presentation, and any family history of autoimmune disease were obtained from the hospital's medical records.

RESULTS

Seventy three (64%) were female patients (mean age: 42.3 ± 15.5; median disease duration: 12 months). We identified the presence of autoimmune disease in 19 patients with achalasia (16.7%), hypothyroidism was the main diagnosis, and it was present in 52.6% of patients compared with 4.2% in controls. Thirteen of the 19 achalasia patients (68.4%) with autoimmune disease had history of familial autoimmunity. We identified 11 achalasia (9.6%) and 5 GERD patients (4.16%) with an inflammatory condition. Compared with the GERD, the achalasia group was 3.8 times more likely to have an autoimmune disease (95% CI: 1.47-9.83), 3.0 times more likely to have thyroidopathies (95% CI: 1.00-9.03), and 3.02 times more likely to suffer from any chronic inflammatory disease (95% CI: 1.65-6.20).

CONCLUSIONS

The non-negligible number of patients with autoimmune diseases identified among the patients with idiopathic achalasia supports the hypothesis that achalasia has an autoimmune component.

Cellular immune response to β2-glycoprotein-I valine/leucine247 phenotypes in Mexican patients with primary antiphospholipid syndrome

Homozygote genotype V²⁴⁷ of the β₂-glycoprotein-I (β₂GP-I) gene has been associated with anti-β₂GP-I and thrombosis in patients with primary anti-phospholipid syndrome APS (PAPS). However, the cellular immune response to β₂GP-I²⁴⁷ has been little studied.

OBJECTIVE

To evaluate the immune cellular proliferation in response to native and non-native β₂GP-I²⁴⁷ valine/leucine phenotype from Mexican patients with PAPS.

METHODS

We studied 10 patients with PAPS and 10 healthy control subjects (HC). The polymorphism at position 247 of the β₂GP-I gene was determined by PCR-RFLP and the corresponding β₂GP-I protein was subsequently purified from normal human plasma by affinity chromatography. PBMC purified from patients and controls were stimulated with β₂GP-I under native and in non native (reduced) conditions. We also determined the anti-β₂GP-I production in vitro by B cell clones (EBV) generated in cocultures experiments. Differential Scanning Calorimetry (DSC) was studied to determine the structural differences between the β₂GP-I²⁴⁷ valine/leucine isoforms. Cytokine profile (IL-2, IL-4, IL-6, TNFα, INFγ) was evaluated in culture supernatants.

RESULTS

PAPS and healthy control PBMCs had a higher proliferative response when stimulated with β₂GP-I under reduced cultures conditions compared to non-denatured conditions. PBMCs response from PAPS patients was higher. We observed more cell proliferation in response to β₂GP-I²⁴⁷ valine/leucine or valine isoforms in non-native conditions. In contrast, this response was not significant against β₂GP-I²⁴⁷ leucine. These findings were T CD4⁺-dependent. Similar results were obtained with B cell clones derived from PAPS patients, which showed more pronounced proliferation in non native conditions and higher against β₂GP-I²⁴⁷ valine. No differences were found in anti-β₂GP-I production, but high levels of IL-6 in vitro were identified. The structural analysis of both β₂GP-I²⁴⁷ isoforms by DSC showed a major conformational change due to a single mutation in the β₂GP-I variants.

CONCLUSIONS

PAPS PBMCs had a higher cellular response against β₂GP-I²⁴⁷ in non-native culture conditions preferentially to the β₂GP-I²⁴⁷ valine phenotype. This effect is T CD4⁺ dependent and appears to be driven by tertiary structural changes adopted by β₂GP-I²⁴⁷ polymorphism.

Chemokine saliva levels in patients with primary Sjögren's syndrome, associated Sjögren's syndrome, pre-clinical Sjögren's syndrome and systemic autoimmune diseases

OBJECTIVE

To assess the saliva levels of CXCL13, CXCL10, CCL2, CCL3, CXCL12 and CCL5 in patients with primary SS (pSS), patients with associated SS (aSS), patients with systemic autoimmune disease (SAD) without SS, pre-clinical SS and healthy controls.

METHODS

We included 44 patients with pSS (Group A), 30 with aSS (Group B), 49 with SAD without SS (Group C), 14 patients with SAD and focal lip infiltrates, but who do not fulfil SS criteria (Group D, pre-clinical SS) and 32 healthy controls (Group E). Saliva samples were collected and analysed for chemokine levels by luminometry. We used descriptive statistics and the Mann-Whitney U-test and Kruskall-Wallis test.

RESULTS

All the studied chemokines were found at low concentration in controls with the exception of CCL2. Patients with pSS had higher levels CXCL10 and CCL2 than controls (P = 0.05). However, they had similar levels of CXCL13, CCL5, CXCL12, CCL2 and CXCL10 than patients with aSS and SAD without SS. Patients with pre-clinical SS had higher levels of CXCL10 than patients with pSS (P = 0.03), aSS (P = 0.04) and controls (P = 0.001). CCL2 levels were higher in all patients with an autoimmune background when compared with controls (P < 0.05 for each comparison).

CONCLUSION

We found no difference in salivary chemokines between patients neither with pSS or aSS nor in patients with SAD. CCL2 and CXCL10 were increased in all patients with an autoimmune background. CXCL10 was notably increased in pre-clinical SS, suggesting it could be an early inflammatory salivary biomarker.

Potential additional effect of omentectomy on metabolic syndrome, acute-phase reactants, and inflammatory mediators in grade III obese patients undergoing laparoscopic Roux-en-Y gastric bypass: a randomized trial

OBJECTIVE

To assess the additional effect of sudden visceral fat reduction by omentectomy on metabolic syndrome, acute-phase reactants, and inflammatory mediators in patients with grade III obesity (G-III O) undergoing laparoscopic Roux-en-Y gastric bypass (LRYGB).

RESEARCH DESIGN AND METHODS

Twenty-two patients were randomized into two groups, LRYGB alone or with omentectomy. Levels of interleukin-6, C-reactive protein, tumor necrosis factor-alpha, leptin, adiponectin, glucose, total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides, as well as clinical characteristics, were evaluated before surgery and at 1, 3, 6, and 12 months after surgery. Results were compared between groups.

RESULTS

Baseline characteristics were comparable in both groups. Mean operative time was significantly higher in the group of patients who underwent omentectomy (P < 0.001). Median weight of the omentum was 795 +/- 341 g. In one patient, a duodenal perforation occurred at the time of omentectomy. BMI, blood pressure, glucose, total cholesterol, LDL, and triglycerides significantly improved in both groups at 1, 3, 6, and 12 months of follow-up when compared with basal values. However, there were no consistent statistically significant differences among the groups in terms of metabolic syndrome components, acute-phase reactants, and inflammatory mediators.

CONCLUSIONS

Omentectomy does not have an ancillary short-term significant impact on the components of metabolic syndrome and does not induce important changes in the inflammatory mediators in patients undergoing LRYGB. Operative time is more prolonged when omentectomy is performed.

Characterization of monoclonal anti-β2-glycoprotein-I and anti-prothrombin antibody fragments generated by phage display from a patient with primary antiphospholipid syndrome

The molecular structure of antibodies associated with autoimmune thrombosis is beginning to be understood. We describe the binding specificities and sequence analysis of anti-beta2-glycoprotein-I (anti-beta2GP-I) or anti-prothrombin (anti-PT) antibody fragments generated by phage display from a patient with primary antiphospholipid syndrome (APS). We obtained 39 positive clones, two that had the correct size reacted with beta2GP-I (Beta 1 and Beta 2). Ten clones with the same restrictive pattern recognized PT (Prot 1) and cross-reacted with beta2GP-I. All three clones recognized anionic and zwitterionic phospholipids. The V(H) regions of both anti-beta2GP-I clones are members of the VH4 family. Prot 1 has a V(H) segment of the VH3 family. The Beta 1 J(H) segments are J(H)5b and J(H)4b for Beta 2 and Prot 1. V(L) genes are V(lambda)1, 3 and 1, respectively. No J(L) was identified for Beta 1, while Beta 2 and Prot 1 carry J(lambda)3b genes. Beta 1 and Beta 2 carry highly conserved germ-line V(H) and V(L) genes. Mutations of the Prot 1 gene appear to be antigen-dependent, most are hotspot mutations located in the CDR 1 and 2 regions. Our work suggests that some anti-beta2GP-I from patients with primary APS are natural autoantibodies. Our work may also help to explain the frequent coexistence of anti-beta2GP-I and anti-PT in the same patient.