ABSTRACT
BACKGROUND: Lung transplant recipients are among those with the highest risk of influenza infection and complications each year. A few studies show adequate responses after influenza immunization; no studies examined the season-long protection. METHODS: Influenza antibody concentrations were measured using hemagglutination inhibition assays before immunization, 2 to 4 weeks after immunization, and 6 months after immunization in 25 healthy controls and 54 lung transplant patients. Two definitions of seroprotection (40 hemagglutination units (HAU) and 160 HAU which confers about 95% protection) were used. RESULTS: Influenza vaccine responses were high in both groups postimmunization (100% at 40 HAU and 60% healthy and 61% lung transplant at 160 HAU; P = 1.0; chi-square). At 6 months after immunization, seroprotection rates at 40 HAU (95% healthy and 97% lung transplant; P = 1.0) and at 160 HAU (24% healthy and 36% lung transplant; P = 0.40) were observed. CONCLUSION: Seroprotection rates do not differ between healthy and transplant groups over 6 months when 40 HAU or 160 HAU is used. However, the seroprotection rates are disappointingly low when 160 HAU (the antibody concentration associated with 95% protection from infection) is used. Annual influenza vaccine should continue to be a high priority for lung transplant patients.
Subject(s)
Antibodies, Viral/blood , Influenza A Virus, H1N1 Subtype/immunology , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Lung Transplantation , Adult , Aged , Biomarkers/blood , Case-Control Studies , Female , Hemagglutination Inhibition Tests , Humans , Influenza A Virus, H3N2 Subtype/immunology , Influenza Vaccines/administration & dosage , Influenza, Human/blood , Influenza, Human/immunology , Influenza, Human/virology , Lung Transplantation/adverse effects , Male , Middle Aged , Predictive Value of Tests , Seasons , Time Factors , Treatment Outcome , VaccinationABSTRACT
We previously mapped a type 2 diabetes (T2D) locus on chromosome 16 (Chr 16) in an F2 intercross from the BTBR T (+) tf (BTBR) Lep(ob/ob) and C57BL/6 (B6) Lep(ob/ob) mouse strains. Introgression of BTBR Chr 16 into B6 mice resulted in a consomic mouse with reduced fasting plasma insulin and elevated glucose levels. We derived a panel of sub-congenic mice and narrowed the diabetes susceptibility locus to a 1.6 Mb region. Introgression of this 1.6 Mb fragment of the BTBR Chr 16 into lean B6 mice (B6.16(BT36-38)) replicated the phenotypes of the consomic mice. Pancreatic islets from the B6.16(BT36-38) mice were defective in the second phase of the insulin secretion, suggesting that the 1.6 Mb region encodes a regulator of insulin secretion. Within this region, syntaxin-binding protein 5-like (Stxbp5l) or tomosyn-2 was the only gene with an expression difference and a non-synonymous coding single nucleotide polymorphism (SNP) between the B6 and BTBR alleles. Overexpression of the b-tomosyn-2 isoform in the pancreatic ß-cell line, INS1 (832/13), resulted in an inhibition of insulin secretion in response to 3 mM 8-bromo cAMP at 7 mM glucose. In vitro binding experiments showed that tomosyn-2 binds recombinant syntaxin-1A and syntaxin-4, key proteins that are involved in insulin secretion via formation of the SNARE complex. The B6 form of tomosyn-2 is more susceptible to proteasomal degradation than the BTBR form, establishing a functional role for the coding SNP in tomosyn-2. We conclude that tomosyn-2 is the major gene responsible for the T2D Chr 16 quantitative trait locus (QTL) we mapped in our mouse cross. Our findings suggest that tomosyn-2 is a key negative regulator of insulin secretion.
Subject(s)
Diabetes Mellitus, Type 2/genetics , Insulin/metabolism , R-SNARE Proteins/genetics , R-SNARE Proteins/metabolism , 8-Bromo Cyclic Adenosine Monophosphate/pharmacology , Adaptor Proteins, Vesicular Transport , Animals , Chromosome Mapping , Cloning, Molecular , Disease Models, Animal , Genetic Predisposition to Disease , Glucose/analysis , HEK293 Cells , Humans , Hypoglycemia/genetics , Insulin Secretion , Islets of Langerhans/metabolism , Islets of Langerhans/pathology , Leptin/genetics , Leptin/metabolism , Mice , Mice, Inbred C57BL , Polymorphism, Single Nucleotide , Qa-SNARE Proteins/genetics , Qa-SNARE Proteins/metabolism , Quantitative Trait Loci/genetics , Rats , SNARE Proteins/metabolism , Syntaxin 1/genetics , Syntaxin 1/metabolismABSTRACT
ERIC, the Enteropathogen Resource Integration Center (www.ericbrc.org), is a new web portal serving as a rich source of information about enterobacteria on the NIAID established list of Select Agents related to biodefense-diarrheagenic Escherichia coli, Shigella spp., Salmonella spp., Yersinia enterocolitica and Yersinia pestis. More than 30 genomes have been completely sequenced, many more exist in draft form and additional projects are underway. These organisms are increasingly the focus of studies using high-throughput experimental technologies and computational approaches. This wealth of data provides unprecedented opportunities for understanding the workings of basic biological systems and discovery of novel targets for development of vaccines, diagnostics and therapeutics. ERIC brings information together from disparate sources and supports data comparison across different organisms, analysis of varying data types and visualization of analyses in human and computer-readable formats.
