Impact of age and pre-existing influenza immune responses in humans receiving split inactivated influenza vaccine on the induction of the breadth of antibodies to influenza A strains.

Most humans have pre-existing immunity to influenza viruses. In this study, volunteers (ages of 18-85 years) were vaccinated with split, inactivated Fluzone™ influenza vaccine in four consecutive influenza seasons from 2013 to 2016 seasons. The impact of repeated vaccination on breadth and durability of antibodies was assessed as a result of vaccine strain changes. Total IgG anti-hemagglutinin (HA) binding antibodies and hemagglutination-inhibition (HAI) activity increased in all age groups against both influenza A HA components in the vaccine post-vaccination (day 21). However, younger subjects maintained seroprotective titers to the vaccine strains, which resulted in higher seroconversion rates in the elderly, since the HAI titers in elderly subjects were more likely to decline prior to the next season. Young subjects had significant HAI activity against historical, as well as contemporary H1 and H3 vaccine strains from the mid-1980s to present. In contrast, elderly subjects had HAI activity to H1 strains from all years, but were more likely to have HAI activity to older strains from 1918-1950s. They also had a more restricted HAI profile against H3 viruses compared to young subjects recognizing H3N2 influenza viruses from the mid-2000s to present. Vaccine recipients were then categorized by whether subjects seroconverted from a seronegative or seropositive pre-vaccination state. Regardless of age, immunological recall or 'back-boosting' to antigenically related strains were associated with seroconversion to the vaccine strain. Overall, both younger and older people have the ability to mount a breadth of immune responses following influenza vaccination. This report describes how imprinting exposure differs across age groups, influences antibody cross-reactivity to past hemagglutinin antigenic variants, and shapes immune responses elicited by current split inactivated influenza vaccines. Understanding how current influenza vaccines are influenced by pre-existing immunity in people of different ages is critical for designing the next-generation of 'universal' or broadly-protective influenza vaccines

Grundlagen und Anwendungen mehrelementiger pyroelektrischer Sensorsysteme (GAMPYS). Teilvorhaben: Sensortechnologien und Messtechnik pyroelektrischer Mehrelementsensoren Abschlussbericht

Pyroelectric single-element and multielement infrared sensors for application in pyrometry, gas analysis and thermography have been developed and tested using lithium tantalate LiTaO_3 as the pyroelectricum. LiTaO_3 wafers were prepared and their pyroelectric and dielectric properties were characterized for different chip layouts. Chip thickness of <5 #mu#m was achieved by ion beam etching. INDAB (induced absorption) layers obtained by on-chip layering of LiTaO_3 wafers and chips were structurated by the lift-off technique. A high-sensitivity single-element sensor, 4-channel and 2-channel multispectral sensors and a 128-element-line sensor were constructed and the sensor characteristics of these prototypes were measured as a function of ambient temperature and chopper frequency. (WEN)SIGLEAvailable from TIB Hannover: F97B596 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

ELISA titers.

<p>The box-and-whisker plots show the lower (Q1) and upper (Q4) quartile representing the IgG endpoint dilution titer for anti-HA antibodies. The diagram also shows the geometric mean titer (GMT) for day 0 and day 21 post-vaccination for each age group. The n value per age group is listed on the x-axis. (A) Serum samples were tested (A) 2014 season against rHA for the H1N1 component of the vaccine, A/California/07/2009 (CA/09). (B) 2015 season against rHA for the H1N1 component of the vaccine, A/California/07/2009 (CA/09). (C) 2014 season against rHA for the H3N2 component of the vaccine, A/Texas/50/2012 (TX/12). (D) 2014 season against rHA for the H3N2 component of the vaccine, A/Switzerland/9715293/2013 (Switz/13). *p≤0.05; *p≤0.01; *p≤0.001; *p≤0.0001.</p

Percent of individuals with antisera with HAI activity that recognized more, fewer, or similar number of strains in the panel post-vaccination compared to pre-challenge.

<p>Percent of individuals with antisera with HAI activity that recognized more, fewer, or similar number of strains in the panel post-vaccination compared to pre-challenge.</p

Heat Map of HAI results.

<p>Serum samples were collected from subjects at day 0 and day 21 post-vaccination and HAI activity of each serum samples was tested against a panel of H1N1 and H3N2 historical influenza viruses. A heat map of each subject’s HAI titer against each strain is depicted for (A) H1N1 2015 season, (B) H3N2 2015 season, (C) H1N1 2016 season, (D) H3N2 2016 season. The list of strains are shown on the upper x-axis in chronological order from left to right, oldest to youngest. The subjects were categorized by each age group (youngest to oldest listed from top to bottom of the heat map) on the y-axis. Those subjects between the ages of 18–34 y.o. are highlighted in red, subject between the ages of 35–49 y.o in green, subject between the ages 50–64 y.o in blue, and 65–85 y.o. in orange. HAI titers greater than 1:40 are highlighted on a color scale and HAI less than 1:40 are highlighted are not colored (1:20, 1:10, and 1:5).</p

Hemagglutination inhibition (HAI) activity in serum antibody induced by Fluzone^™.

<p>HAI titers were determined from pre- and post-vaccination serum samples against H1N1 (A-D) and H3N2 (E-H). Values of each individual titer are the geometric mean titers plus standard errors of the means (SEM) (error bars). The box-and-whisker plots show the lower (Q1) and upper (Q4) quartile representing the IgG endpoint dilution titer for anti-HA antibodies. The diagram also shows the GMT for day 0 and day 21 post-vaccination for each age group against H1N1 (A-D) and H3N2 (E-H) components of the vaccine. The n value per age group is listed on the x-axis. Serum samples were tested (A and E) 2013 season, (B and F) 2014 season, (C and G) 2015 season, (D and H) 2016 season. *p≤0.05; *p≤0.01; *p≤0.001; *p≤0.0001.</p

Seropositivity over multiple influenza seasons.

<p>Subjects were immunized over 3 consecutive seasons, 2014, 2015, and 2016. Each subject was assessed for seropositive titers to the H1N1 and H3N2 components of the vaccine at day 0 and day 21 immunized were categorized according to their seroprotection status at each of the 6 time points analyzed (<i>i</i>.<i>e</i>., days 0 and 21 in all 3 years). Subjects in each age group that had HAI titers less than 1:40 at all 6 time points were assigned a value of “0”. Subjects with an HAI titer of 1:40 or greater at one of the 6 time points was categorized as a “1”. Subjects with an HAI titer of 1:40 or greater at two of the 6 times was categorized as a “2”, at three of the 6 time points, was categorized as a “3”, at four of the 6 times was categorized as a “4”, at five of the 6 times was categorized as a “5”, and subjects with was greater than 1:40 all 6 times was categorized as a “6”. Pie charts for each of these 7 categories was assessed for each age group against the H1N1 or H3N2 component. The n value for each age group was listed beneath each pie chart.</p

Le Courrier

20 novembre 18481848/11/20 (N323)

Hemagglutinin-inhibition (HAI) GMT.

<p>Hemagglutinin-inhibition (HAI) GMT.</p