Evaluation of Patient-Reported Outcome in Subjects Treated Medically for Acute Pancreatitis: A Follow-Up Study

Aims: To explore the quality of life in patients treated medically during the acute phase of pancreatitis as well as at 2 and 12 months after discharge from the hospital. Patients: 40 patients were studied. The etiology of the pancreatitis was biliary causes in 31 patients and non-biliary causes in 9; mild disease was present in 29 patients and severe disease in 11. 30 patients completed the two surveys at 2 and 12 months after hospital discharge. Methods: The SF-12 and EORTC QLQ-C30 questionnaires were used for the purpose of the study. Results: The two physical and mental component summaries of SF-12, all the domains of EORTC QLQ-C30 (except for physical functioning and cognitive functioning) and some symptom scales of EORTC QLQ-C30 (fatigue, nausea/ vomiting, pain, and constipation) were significantly impaired during the acute phase of pancreatitis. There was a significant improvement in the SF-12 physical component summary, and global health, role functioning, social functioning, nausea/vomiting, pain, dyspnea, and financial difficulties (EORTC QLQ-C30) at 2 months after discharge as compared to the basal evaluation. Similar results were found after 12 months except for the mental component score at 12-month evaluation, which was significantly impaired in acute pancreatitis patients in comparison to the norms. The physical functioning of the EORTC QLQ-C30 at basal evaluation was significantly impaired in patients with severe pancreatitis in comparison to patients with mild pancreatitis. Conclusions: Two different patterns can be recognized in the quality of life of patients with acute pancreatitis: physical impairment is immediately present followed by mental impairment which appears progressively in the follow-up period.     

IgG naturally occurring antibodies stabilize and promote the generation of the alternative complement pathway C3 convertase

Normal human IgG contains naturally occurring anti-C3 antibodies (anti-C3 NAbs) that have been proposed to regulate complement amplification. Here, we report a novel procedure for anti-C3 NAb purification. Pooled human IgG was fractionated on a DEAE column prior to affinity chromatography on IgG and then on C3. Anti-C3 NAbs co-purified with anti-F(ab')2 NAbs. In a refined protocol, IgG fractions were absorbed on Fc, F(ab')2, and C3, which allowed to isolate the directly accessible NAbs and to remove IgG hinge-region-specific NAbs. Since a substantial fraction of total anti-C3 NAbs in whole IgG pre-existed as complexes, IgG that did not bind to the three affinity columns was treated with urea and the affinity chromatography repeated to collect the dissociated NAbs. The urea-accessible anti-F(ab')2 NAbs were rather pure but anti-C3 NAbs yet contained substantial amounts of anti-F(ab')2 NAbs. Anti-C3 NAbs showed up to 400-fold and anti-F(ab')2 NAbs, up to 30-fold enrichment as compared to pooled normal human IgG. Anti-C3 NAb preparations exhibited nephritic factor activity that was up to 60 times stronger than that of total IgG from a patient with membranoproliferative glomerulonephritis type 2. In addition, anti-C3 NAbs promoted C3 convertase generation, when added to the convertase precursor or during convertase assembly, suggesting a non-nephritic-factor mechanism. Factors H and I reduced the overall level of activity but had no influence on the NAb dose-response curve meaning that NAbs did not interfere with factor H binding. Convertase promoting activity during assembly correlated with the content of anti-C3 NAbs in NAb complexes. In conclusion, anti-C3 NAbs associated with framework-specific anti-idiotypic NAbs stabilize C3 convertase and promote its generation but their activity is compensated for in whole IgG.     

Haemophilus influenzae porin induces Toll-like receptor 2-mediated cytokine production in human monocytes and mouse macrophages

The production of proinflammatory cytokines is likely to play a major pathophysiological role in meningitis and other infections caused by Haemophilus influenzae type b (Hib). Previous studies have shown that Hib porin contributes to signaling of the inflammatory cascade. We examined here the role of Toll-like receptors (TLRs) and the TLR-associated adaptor protein MyD88 in Hib porin-induced production of tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6). Hib porin-induced TNF-alpha and IL-6 production was virtually eliminated in macrophages from TLR2- or MyD88-deficient mice. In contrast, macrophages from lipopolysaccharide (LPS)-hyporesponsive C3H/HeJ mice, which are defective in TLR4 function, responded normally to Hib porin. Moreover anti-TLR2 antibodies but not anti-TLR4 antibodies significantly reduced Hib porin-stimulated TNF-alpha and IL-6 release from the human monocytic cell line THP-1. These data indicate that the TLR2/MyD88 pathway plays an essential role in Hib porin-mediated cytokine production. These findings may be useful in the development of alternative therapies aimed at reducing excessive inflammatory responses during Hib infections.     

Levels of Expression and Immunogenicity of Attenuated Salmonella enterica Serovar Typhimurium Strains Expressing Escherichia coli Mutant Heat-Labile Enterotoxin

The effects of heterologous gene dosage as well as Salmonella typhimurium strain variability on immune response toward both the heterologous antigen, the nontoxic mutant of the Escherichia coli heat-labile enterotoxin LTK63, and the carrier Salmonella strain have been analyzed. Effects of a single integration into the host DNA and different-copy-number episomal vectors were compared in S. typhimurium Δcya Δcrp Δasd strains of two different serotypes, UK-1 and SR-11. Expression of the enterotoxin in the different Salmonella isolates in vitro was found to vary considerably and, for the episomal vectors, to correlate with the plasmid copy number. LTK63-specific serum immunoglobulin G (IgG) and mucosal immunoglobulin A (IgA) antibodies were highest in mice immunized with the high-level-expression strain. High anti-LTK63 IgG and IgA titers were found to correspond to higher anti-Salmonella immunity, suggesting that LTK63 exerts an adjuvant effect on response to the carrier. Statistically significant differences in anti-LTK63 immune response were observed between groups of mice immunized with the attenuated Δcya Δcrp UK-1 and SR-11 derivatives producing the antigen at the same rate. These data indicate that the same attenuation in S. typhimurium strains of different genetic backgrounds can influence significantly the immune response toward the heterologous antigen. Moreover, delivery of the LTK63 enterotoxin to the immune system by attenuated S. typhimurium strains is effective only when synthesis of the antigen is very high during the initial phase of invasion, while persistence of the S. typhimurium strain in deep tissues has only marginal influence.

Enterotoxigenic Escherichia coli strains produce a plasmid-encoded heat-labile enterotoxin (LT) (15, 34) related to cholera toxin (CT) (9, 35). LT is composed of two subunits, A and B, which are exported to the periplasmic space, where they assemble into an AB₅ multimeric complex (16). Several mutants of LT-A have been constructed, and in particular, a nontoxic mutant which contains a substitution of serine 63 with lysine (LTK63) has been shown to maintain the structural and immunogenic properties of wild-type LT (21, 27, 28). LTK63 has also been found to display the strong mucosal adjuvant activity pertaining to wild-type LT. Efficient induction of mucosal immune response, specifically in the mouse vagina, has been achieved via the intranasal route of immunization (10). For the development of oral vaccines, however, it would be desirable to exploit the properties of LTK63 for enhancing antigen-specific immune response in the intestinal mucosa by means of oral delivery of the potent mucosal adjuvant.Oral delivery of antigens by live vaccines is known to lead to a more effective production of antigen-specific antibodies in mucosal secretions than oral administration of the soluble antigen (36, 39). Several antigen delivery systems which use as carriers mutant intracellular pathogens that have lost the ability to persist and produce the disease while retaining limited growth in vivo have been developed. In particular, attenuated Salmonella mutants are suitable immunological carriers for virulence determinants from other enteric bacteria in that they can induce humoral immune response selectively at the site of colonization, the gut mucosa. Vaccine strains of Salmonella have been successfully attenuated by introducing different types of mutations (5, 8, 23, 26). Notably, Salmonella strains with a galactose epimerase (galE) mutation (18) or deletions in genes for the biosynthesis of aromatic compounds (aro mutants) (11, 12, 17, 19) or in the adenylate cyclase (cya) and cyclic AMP receptor protein (crp) genes (6) are the most extensively characterized.Delivery of the B subunit of the E. coli enterotoxin (LT-B) by a galE mutant of Salmonella typhimurium has been shown to elicit low levels of anti-LT-B serum and mucosal antibodies. Since the vector used for expression of LT-B was rapidly lost in vivo, i.e., in the absence of the antibiotic required for selection of the plasmid, the level of immune response could be correlated only with the amount of antigen expressed during the initial phase of invasion (3).Recently, direct comparison between the aroA aroD/pnirB and the Δcya Δcrp Δasd/asd⁺ delivery systems for the ability to induce humoral and cellular immunity after a single immunization showed that the former vaccine strain had greater potential as a carrier for antigen delivery (20). However, the balanced lethal asd system for in vivo selection of plasmids expressing heterologous antigens in the attenuated Δcya Δcrp Δasd strains is still very attractive in that asd⁺ plasmids do not require antibiotic resistance markers for selection while stably maintained in vivo (24). In addition, the Δcya Δcrp Δasd/asd⁺ delivery system has been reported to induce protective immunity against several pathogens (25, 29, 40). Most of these studies have restricted analysis of the immune response to antigens expressed from the same asd⁺ plasmid carried by Δcya Δcrp Δasd mutants usually of the same S. typhimurium serotype. In this work, we have analyzed the influence of heterologous gene dosage, and thus level of expression, as well as S. typhimurium strain variability on immune response toward both the heterologous antigen, a nontoxic mutant of E. coli LT, and the carrier Salmonella strain. Effects of a single integration into the host DNA and episomal vectors at different copy numbers were compared in S. typhimurium strains of two different Δcya Δcrp Δasd serotypes, UK-1 and SR-11.     

Cross-Sectional Serosurvey of Companion Animals Housed with SARS-CoV-2–Infected Owners,Italy

We conducted a serologic survey among dogs and cats in Italy to detect antibodies against severe acute respiratory syndrome virus 2 (SARS-CoV-2). We found that SARS-CoV-2 seroprevalence was higher among cats (16.2%) than dogs (2.3%). In addition, seroprevalence was higher among animals living in close contact with SARS-CoV-2–positive owners.     

Gastric endocrine tumors type I: treatment with long-acting somatostatin analogs

Gastric endocrine tumors associated with autoimmune chronic atrophic gastritis (gastric carcinoid type I) are almost exclusively benign lesions with little risk of deep invasion of the gastric parietal wall. For this reason, the role of octreotide in the treatment of these neoplastic lesions is controversial. Nine patients with more than five type I gastric endocrine tumors each <1 cm in size, without invasion of the muscularis propria and with Ki-67 index lower than 3%, were treated with long-acting somatostatin analogs for 12 months. After 6 months and again after 12 months, all the patients underwent upper gastrointestinal (GI) endoscopy with multiple biopsies. The plasma chromogranin A (CgA) levels and the gastrin levels in the serum were also determined. In all patients, the gastric neoplastic lesions disappeared after 12 months of somatostatin analog therapy. We also observed a significant reduction of CgA and gastrin levels at 6 and at 12 months of therapy as compared with the baseline values. We demonstrate that somatostatin analog treatment provokes the pathological regression of type I gastric carcinoids. This therapeutic approach should be considered as a valid option in selected patients with multiple type I gastric endocrine tumors.