Roberto Luisetto

Galectin-3 in autoimmunity and autoimmune diseases:

Galectin-3 (gal-3) is a β-galactoside-binding lectin, which regulates cell–cell and extracellular interactions during self/non-self-antigen recognition and cellular activation, proliferation, differentiation, migration and apoptosis. It plays a significant role in cellular and tissue pathophysiology by organizing niches that drive inflammation and immune responses. Gal-3 has some therapeutic potential in several diseases, including chronic inflammatory disorders, cancer and autoimmune diseases. Gal-3 exerts a broad spectrum of functions which differs according to its intra- or extracellular localization. Recombinant gal-3 strategy has been used to identify potential mode of action of gal-3; however, exogenous gal-3 may not reproduce the functions of the endogenous gal-3. Notably, gal-3 induces monocyte–macrophage differentiation, interferes with dendritic cell fate decision, regulates apoptosis on T lymphocytes and inhibits B-lymphocyte differentiation into immunoglobulin secreting plasma cells. Considering the influence of these cell populations in the pathogenesis of several autoimmune diseases, gal-3 seems to play a role in development of autoimmunity. Gal-3 has been suggested as a potential therapeutic agent in patients affected with some autoimmune disorders. However, the precise role of gal-3 in driving the inflammatory process in autoimmune or immune-mediated disorders remains elusive. Here, we reviewed the involvement of gal-3 in cellular and tissue events during autoimmune and immune-mediated inflammatory diseases.

Induction of the ‘ASIA’ syndrome in NZB/NZWF1 mice after injection of complete Freund’s adjuvant (CFA)

Adjuvants, commonly used in vaccines, may be responsible for inducing autoimmunity and autoimmune diseases, both in humans and mice. The so-called ‘ASIA’ (Autoimmune/inflammatory Syndrome Induced by Adjuvants) syndrome has been recently described, which is caused by the exposure to a component reproducing the effect of adjuvants. The aim of our study was to evaluate the effect of injection of complete Freund’s adjuvant (CFA) in NZB/NZWF1 mice, a lupus-prone murine model. We injected 10 NZB/NZWF1 mice with CFA/PBS and 10 with PBS, three times, 3 weeks apart, and followed-up until natural death. CFA-injected mice developed both anti-double-stranded DNA and proteinuria earlier and at higher levels than the control group. Proteinuria-free survival rate and survival rate were significantly lower in CFA-treated mice than in the control mice (p = 0.002 and p = 0.001, respectively). Histological analyses showed a more severe glomerulonephritis in CFA-injected mice compared with the control mice. In addition, lymphoid hyperplasia in spleen and lungs, myocarditis, and vasculitis were observed in the former, but not in the latter group. In conclusion, the injection of CFA in NZB/NZWF1 mice accelerated autoimmune manifestations resembling ‘ASIA’ syndrome in humans.

High-density lipoproteins inhibit urate crystal-induced inflammation in mice

OBJECTIVES To investigate the effects and mechanisms of action of high-density lipoproteins (HDL) in monosodium urate (MSU) crystal-induced inflammation -that is, gouty inflammation, in vivo. METHODS Air pouches raised on the backs of mice were injected with MSU crystals or tumour necrosis factor (TNF) in the presence or absence of HDL and/or interleukin (IL)-1 receptor antagonist (IL-1Ra) for 3 h. Leucocyte count and neutrophil percentage in pouch fluids were measured using a haemocytometer and May-Grünwald-Giemsa staining. The cytokine production and expression in the pouch were measured by ELISA and quantitative RT-PCR. RESULTS MSU crystals induced leucocyte infiltration, mostly neutrophils, and the release of IL-1β, IL-6, chemokine (C-X-C motif) ligand 1 (CXCL1), chemokine (C-C motif) ligand 2 (CCL2) and IL-1Ra in pouch fluids. TNF remained under the detection limit. MSU crystals triggered IL-1β, IL-6 and CXCL1 expression in both pouch exudates and membranes, whereas CCL2 and TNF mRNA were not modulated. The co-injection of MSU crystals and HDL inhibited leucocyte influx by 59% and neutrophil infiltration by 83% and, in turn, both protein and mRNA levels of all assessed proinflammatory cytokines were reduced, but not those of IL-1Ra. Similar results were obtained when mice were injected with MSU crystals pretreated with HDL or TNF instead of crystals. When HDL and IL-1Ra were added together they displayed additional inhibition, suggesting different mechanisms of action. CONCLUSIONS This study demonstrated that HDL may represent an important factor in the modulation of gouty inflammation by acting on both tissue and infiltrating cells -that is, synovial tissue and synovial fluid cells. HDL display anti-inflammatory activity, in part, by interacting with crystals but also by directly acting on cells.

Post-traumatic arthritis: overview on pathogenic mechanisms and role of inflammation

Post-traumatic arthritis (PTA) develops after an acute direct trauma to the joints. PTA causes about 12% of all osteoarthritis cases, and a history of physical trauma may also be found in patients with chronic inflammatory arthritis. Symptoms include swelling, synovial effusion, pain and sometimes intra-articular bleeding. Usually, PTA recoveries spontaneously, but the persistence of symptoms after 6 months may be considered pathological and so-called chronic PTA. A variety of molecular, mechanobiological and cellular events involved in the pathogenesis and the progression of PTA have been identified. The activation of inflammatory mechanisms during the PTA acute phase appears to play a critical role in the chronic disease onset. Human studies and experimental models have revealed that a series of inflammatory mediators are released in synovial fluid immediately after the joint trauma. These molecules have been proposed as markers of disease and as a potential target for the development of specific and preventative interventions. Currently, chronic PTA cannot be prevented, although a large number of agents have been tested in preclinical studies. Given the relevance of inflammatory reaction, anticytokines therapy, in particular the inhibition of interleukin 1 (IL-1), seems to be the most promising strategy. At the present time, intra-articular injection of IL-1 receptor antagonist is the only anticytokine approach that has been used in a human study of PTA. Despite the fact that knowledge in this area has increased in the past years, the identification of more specific disease markers and new therapeutic opportunities are needed.

Vaccination of mice for research purpose: alum is as effective as and safer than complete Freund adjuvant.

Systemic lupus erythematosus (SLE) is an autoimmune disease involving many organ systems. Glomerulonephritis (GLN) is one of the major causes of morbidity and mortality in SLE. It has recently been demonstrated that adjuvants of vaccines could cause the so called ASIA syndrome. The study aimed to assess the effects of Complete Freunds Adjuvant (CFA) vs alum injections in NZB/NZWF1 mice. Mice (n=10 each group) were injected with a total volume of 200 μL of: CFA in PBS (group 1), alum in PBS (group 2), PBS (group 3) as controls, PTX3/CFA (group 4), PTX3/alum (group 5), 3 times, 3 weeks apart /given in each injection, three weeks apart from ten weeks of age. Urine samples were collected weekly to evaluate proteinuria. Blood samples were collected before every injection, at 21 weeks of age, and at death to evaluate levels of anti-PTX3 and anti-dsDNA. Proteinuria free survival and survival rates were analyzed by the Kaplan-Meier method using Mantel-Coxs test for comparisons. CFA-treated mice developed both anti-dsDNA antibodies and proteinuria earlier and at higher levels than alumtreated and PBS-injected mice, starting from 13 weeks of age. Proteinuria free survival rates (proteinuria ≥ 300 mg/dL) and survival rates were lower in CFA-treated mice than those treated with alum or injected with PBS (P<0.001 for all). No difference was observed between the alum-treated group and PBS-injected mice. Notably, groups 4 and 5, immunized with PTX3, developed anti-PTX3 antibodies and no significant difference was observed. Alum seems to be as effective as and safer than CFA as adjuvant, since it did not affect disease progression in immunized NZB/NZWF1 mice.

Ileorectal bypass performed entirely through a transanal route in a porcine model

BackgroundNatural orifice transluminal endoscopic surgery (NOTES), a new frontier of minimally invasive surgery, uses the body’s natural orifices to create an access for surgical procedures. This study aimed to verify the technical feasibility of ileorectal bypass performed entirely through a transanal access.MethodsThe procedure was performed on 10 domestic pigs, after which they were killed. A transanal endoscopic microsurgery (TEM) device and endoscopic and laparoscopic instruments were used.ResultsThe findings demonstrated that an ileorectal bypass through a transanal access is feasible. The principal steps of a standardized transanal procedure are as follows: confirm a rectal perforation above the peritoneal reflection, perform peritoneoscopy using a standard gastroscope, grasp the small bowel with retrieval forceps and pull it through the rectal hole, suture the ileum and the rectum together using a TEM device, open the ileal loop, and perform endoscopic exploration. Satisfactory anastomosis and no signs of procedure-related complications were confirmed by a post procedure laparotomy.ConclusionsIleorectal bypass through a transanal access is technically feasible in a porcine model, and although still at an experimental stage, it could become a surgical option for treating some types of colonic strictures.

Unstabilized DNA Breaks in Lymphocytes of Patients with Different Subsets of Systemic Sclerosis

Abstract:  The clastogenic effects on DNA, proven by the presence of micronuclei (MN) and the protective cellular mechanisms normally used to stabilize DNA breaks were investigated in three subsets of patients with systemic sclerosis (SSc). The frequency of MN found in cultures of peripheral lymphocytes in patients with anticentromere and antitopoisomerase I antibodies was significantly higher than that in the control group. The group with anticentromere antibody showed a significantly higher frequency of MN than did the subjects with antitopoisomerase antibody (4.22% versus 2.34%, P < 0.001). Patients with anti‐RNA polymerase III, instead, had a low prevalence of typical micronucleated cells (0.98%), not significantly different from that of the healthy controls (0.82%). Moreover, when MN was characterized for the presence or absence of DNA fragments with free 3′‐OH ends by digoxigenin‐dUTP (DIG‐dUTP) using terminal deoxynucleotidil transferase, its frequency was found to be increased in the groups with anticentromere and antitopoisomerase I antibodies with respect to that in the controls. The increase was significantly higher in the lymphocytes of the patients with anticentromere than in those with antitopoisomerase I antibody (35% versus 20.08%, P < 0.001). Nonetheless, the prevalence of unstable DNA fragments in patients with anti‐RNA polymerase III antibody was low (2.05%) and not significantly different from that of the control group (1.18%). Our results indicate that there is a clastogenic effect on DNA and an interference in the protective cellular mechanisms normally stabilizing DNA breaks only in some subsets of SSc patients.

Synovial fluid proteins are required for the induction of interleukin-1β production by monosodium urate crystals

Objectives: Monosodium urate (MSU) crystal deposition in gouty joints promotes the release of inflammatory mediators, in particular interleukin (IL)-1β. The induction of IL-1β production by MSU crystals requires a co-stimulus. The objective of this study was to determine which part of the synovial fluid (SF) provides co-stimulation to MSU crystals to induce IL-1β in macrophages. Method: The lipidic fraction (LF) and the protein fraction (PF) were isolated from the SF of patients with arthropathies. The PF was subfractionated according to different molecular weight (MW) ranges. THP-1 cells or human primary monocytes were stimulated with MSU crystals in the presence or absence of SF or SF fractions. IL-1β and IL-8 production and IL-1β mRNA expression were assessed by an enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qPCR). Results: Exposure of monocytes/macrophages to MSU crystals alone induced the moderate release of IL-8 but not of IL-1β. The production of IL-1β required the presence of both SF from patients with inflammatory arthritis (SFi) and MSU crystals. SF from patients with non-inflammatory arthritis, that is patients with osteoarthritis (OA), did not affect the IL-1β production but slightly enhanced the secretion of IL-8. Both MSU crystals and SFi were required for the induction of the IL-1β transcript, which was not expressed in the presence of either stimulus alone. SFi fractionation demonstrated that the MSU crystal co-stimulus was contained in the PF of SFi with MW > 50 kDa but not in the LF. Conclusions: This study shows that the SF of inflammatory arthritis patients, including gout patients, contains proteins required for the induction of IL-1β by MSU crystals in macrophages whereas lipids are not involved.

Roux-en-Y gastrojejunal bypass using a hybrid NOTES-12 mm trocar technique in a porcine model.

Abstract Aims To evaluate the feasibility and safety of Roux-en-Y gastrojejunal bypass procedure using a hybrid NOTES-12 mm trocar technique in a survival porcine model. Material and methods The procedure was carried out on ten pigs. Two gastroscopes were introduced through the mouth and through a 12 mm trocar, respectively. A mechanical circular gastro-jejunal anastomosis was created by introducing a stapler after the trocar incision was enlarged. A 21 mm EEA OrVil circular stapler was utilized in the first six pigs and a 25 mm one was used in the other four. All pigs were fed beginning 24 hours after the procedure and were euthanized three weeks later. Results The procedure was successfully completed in all ten animals. The mean length of the skin incision was 2.5 cm. All pigs survived without complications. Endoscopic inspection detected anastomotic strictures in 5/6 of the 21 mm-stapler and in 0/4 of the 25 mm-stapler anastomoses ( p < 0.05). Conclusion Roux-en-Y gastrojejunal bypass using a hybrid NOTES-single 12 mm trocar access technique is a simple and safe procedure in a survival porcine model. Functional results need to be evaluated by further studies.

S7A:7 Administration of serpinb3 delays glomerulonephritis and attenuates the lupus-like disease in lupus murine models by an immunomodulatory effect

Background Abnormal apoptosis and clearance of cellular debris concur to development of systemic lupus erythematosus (SLE). SERPINS (serin-protease inhibitors) are ancient molecules regulating immune homeostasis. SERPINB3 modulates apoptosis and is hypoexpressed on SLE B cells. Aim To explore the effects of SERPINB3 administration in murine lupus models, focusing on glomerulonephritis. Methods NZB/W F1 and MRL/lpr mice were used. 40 NZB/W F1 mice were divided into 4 groups of 10 mice each and intraperitoneally injected twice a week starting before occurrence of proteinuria traces (group 1 and 2, prophylactic approach) or after development of proteinuria 30 mg/dl (group 3 and 4, therapeutic approach) with hrSERPINB3 (7.5 µg/0.1 mL prophylactic approach, or 15 µg/0.1 mL therapeutic approach) or PBS (0.1 mL). 20 MRL/lpr mice were injected with hrSERPINB3 (group 5, n=10) or PBS (group 6, n=10) with a prophylactic approach. We assessed time of occurrence and titers of anti-dsDNA and anti-C1q antibodies by ELISA; proteinuria and serum creatinine; overall- and proteinuria-free survival. Six NZB/W F1 mice were sacrificed at week 27, while 10 MRL/lpr mice at week 13 and another 10 at 16/18 weeks for histological kidneys comparison. Flow-cytometry was performed on MRL/lpr splenocytes. Non parametric tests were performed for statistics; proteinuria-free (<300 mg/dl) and overall survival were evaluated by Kaplan-Meier method. Results Levels of autoantibodies were significantly decreased and delayed in group 1 vs group 2, group 3 vs group 4, and group 5 vs group 6 (p<0.0001 for all). Proteinuria levels were significantly reduced and proteinuria-free and overall survival were significantly improved in SERPINB3 groups vs controls (figure 1). No differences were found among creatinine serum levels. Histological analysis showed a lower prevalence of severe tubular lesions in group 5 vs group 6 MRL/lpr mice at week 16 (chi-squared p=0.014), and mice belonging to SERPINB3 groups showed a trend toward a reduced prevalence of severe glomerular and tubular lesions. Th17:Treg ratio significantly decreased due to a remarkable increase in Treg levels in MRL/lpr mice treated with SERPINB3. Conclusions Administration of SERPINB3 significantly improves disease and delays the onset of severe glomerulonephritis in lupus-prone mice. SERPINB3 may influence immune-cell function through immunoregulatory effects involving promotion of Treg.Abstract S7A:7 Figure 1 Survival in NZB/W F1 brought to natural death