Long-term and cross-reactive immunogenicity of inactivated trivalent influenza vaccine in the elderly: MF59-adjuvanted vaccine versus unadjuvanted vaccine.

Elderly people are at great risk for influenza-related serious complications. However, influenza vaccine-induced antibodies are believed to decline more rapidly in the elderly. This study was designed to evaluate the long-term and cross-reactive immunogenicity among those aged ≥65 years for two seasonal trivalent influenza vaccines during the 2009-2010 influenza season. One vaccine had the MF59 adjuvant, while the other did not contain an adjuvant. Serum hemagglutinin inhibition (HI) titers were determined pre-vaccination and at 1 and 6 months post-vaccination. Of the 100 subjects, 95 (95%) were followed-up for 1 month after vaccination, and 76 (76%) were followed-up for 6 months after vaccination. Both vaccines met the European Medicines Agency (EMA) criteria 1 month after vaccination. However, seroprotection for influenza B was not satisfactory, with a rate of 55.3% for the MF59 adjuvant vaccine and 47.9% for the vaccine without adjuvant. At 6 months post-vaccination, the MF59-adjuvanted vaccine showed a higher seroprotection rate than the unadjuvanted vaccine. At this point, the MF59-adjuvanated vaccine still met the criteria of EMA for A/H1N1 (62.5% vs. 55.5%, P = 0.64) and A/H3N2 (72.5% vs. 47.2%, P = 0.04). Both vaccines showed excellent cross-reactive immunogenicity for influenza A/Solomon Island/3/2006 (H1N1) and A/Wisconsin/67/2005 (H3N2), without significant differences. In comparison, cross-reactive immunogenicity was not remarkable for the A/California/7/2009 (H1N1) and A/New Caledonia/20/1999 (H1N1) strains, which have a greater antigenic distance. In conclusion, the MF59-adjuvanted influenza vaccine showed superior long-term immunogenicity in the elderly compared to the unadjuvanted vaccine. However, cross-reactive immunogenicity was not remarkably enhanced with the MF59 adjuvant.

Elevated vaspin and leptin levels are associated with obesity in prepubertal Korean children.

Adipokines are associated with obesity. However, the relationships between adipokines, specifically vaspin, obesity, and obesity-related variables remain controversial, and only a few studies have been conducted which examines them in children. We investigated the relationships between obesity in prepubertal Korean children and three types of adipokines: vaspin, leptin, and visfatin. In this cross-sectional study, 168 nine-year-old boys and 176 nine-year-old girls participated in a school-based health examination program. Children were classified as overweight using the Korean Pediatric Society 2007 guidelines. Overweight boys and girls had higher leptin and vaspin levels than both boys and girls of normal weight, whereas only overweight boys had higher visfatin levels than normal weight boys. Leptin, visfatin and vaspin concentrations were correlated with obesity-related variables. A multiple logistic regression analysis showed that systolic blood pressure (SBP), total cholesterol (TC), alanine aminotransferase (ALT), homeostasis model assessment of insulin resistance (HOMA-IR), leptin, and vaspin were associated with an increased risk of being overweight, whereas high-density lipoprotein (HDL) cholesterol was associated with a decreased risk of being overweight. Elevated vaspin and leptin levels are associated with obesity in prepubertal Korean children.

Lifestyle modification increases circulating adiponectin concentrations but does not change vaspin concentrations.

The objective of the study was to evaluate the effects of a 10-month lifestyle intervention on the components of the metabolic syndrome (MetSyn) in Koreans with MetSyn as well as on blood concentrations of adiponectin and vaspin. One hundred thirty-eight patients with MetSyn, recruited from a community health care center, were consecutively enrolled in the study; 12 patients dropped of the intervention, leaving 126 subjects (76 men and 50 women; age, 65.3 ± 9.0 years). All participants followed a 10-month lifestyle modification interventional program, including dietary counseling, advice on increasing physical activity, and recommendations to stop or limit smoking and alcohol drinking. Anthropometric and biochemical parameters related to the components of the MetSyn, including blood concentrations of adiponectin and vaspin, were assessed pre- and postintervention. At baseline, adiponectin concentrations were moderately negatively correlated to insulin concentrations and insulin resistance evaluated by the homeostasis model assessment. In response to lifestyle modification, statistically significant changes were found in systolic and diastolic blood pressure, total cholesterol, triglyceride, and insulin concentrations, as well as in homeostasis model assessment of insulin resistance. Adiponectin concentrations postintervention, compared with the preintervention levels, increased (7.2 ± 4.0 vs 6.8 ± 3.9 µg/mL, respectively; P < .05), whereas vaspin concentrations remained unchanged (0.25 ± 0.19 vs 0.26 ± 0.20 ng/mL, respectively; P = .64). A 10-month lifestyle modification program in Korean patients with MetSyn led to favorable changes in metabolic parameters and adiponectin but not vaspin concentrations.

Long-term immunogenicity of influenza vaccine among the elderly: Risk factors for poor immune response and persistence.

The elderly have been considered as the priority group for influenza vaccination, but their influenza vaccine-induced antibody was believed to decline more rapidly. Long-term immunogenicity of the influenza vaccine among the elderly was evaluated as compared to young adults. Serum hemagglutinin inhibition (HI) titers were determined at pre- and post-vaccination periods (at 1, 6, and 12 months after vaccination). Of the 1018 subjects, 716 (70.3%) were followed up during a 12-month period. Seroprotection rates at 1 month post-vaccination ranged from 70.1% to 90.3% depending on the age group and influenza vaccine virus strain. At 6 months post-vaccination, seroprotection rates for all three strains had declined significantly in adults >or=65 years (P<0.01), but still met the EMEA criteria. Low pre-vaccination HI titer (<1:40) and advanced age were associated with early decline of HI titers, falling below seroprotective levels around 6 months after vaccination.