Hemagglutination inhibition antibody titers

1. ILT2+ CD57+ CD56dim NK cell frequency mediates hemagglutination inhibition antibody titers in humans (40%).

   “ILT2(+)CD57(+) Dim NK-cells mediated 40% of the association between IL-6 and A/H3N2 titres”

   Human trialassociation between IL-6 and A/H3N2 titres

   Markers of systemic inflammation are positively associated with influenza vaccine antibody responses with a possible role for ILT2(+)CD57(+) NK-cells

   Immunity & ageing : I & A·May 26, 2022

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1. Antigen-specific CD4+ T cell frequency is associated with hemagglutination inhibition antibody titers in humans (r = 0.42).

   “correlated with lower H3N2 hemagglutination inhibition antibody titers (r = 0.42, P = 0.008)”

   Humansin responders following vaccinationn = 34

   Influenza vaccine-specific CD4⁺ T cell responses are impaired in older adults

   NPJ vaccines·Apr 10, 2026

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1. TNFSF10+ LGALS9+ NK cells are associated with hemagglutination inhibition antibody titers in humans.

   “their increased frequency correlates with high pre-existing HAI titers, suggesting a link between adaptive-like NK responses and humoral immunity.”

   Humans

   Adaptive-like NK cell responses to influenza correlate with humoral immunity and are influenced by age and sex

   bioRxiv : the preprint server for biology·May 28, 2025Preprint

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1. Immunotypes are associated with hemagglutination inhibition antibody titers in humans.

   “we identified two pre-vaccination immunotypes associated with weak and one showing robust day 28 antibody response.”

   Humanspre-vaccination immunotypeswhole blood28 daysn = 307

   Pre-vaccination immunotypes reveal weak and robust antibody responders to influenza vaccination

   Aging cell·Dec 25, 2023

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1. Chronological age is associated with hemagglutination inhibition antibody titers in humans (rho = -0.3689, P < 0.0001).

   “there was a significant negative correlation between chronological age (years) and post-vaccination HAI titers against H1N1 (rho = -0.2298, P < 0.0001), B/Victoria (rho = -0.2235, P = 0.0037), and B/Yamagata (rho = -0.3689, P < 0.0001).”

   Human trialpost-vaccinationbloodn = 167

   Immunogenicity and safety of quadrivalent influenza vaccine among young and older adults in Tianjin, China: implication of immunosenescence as a risk factor

   Immunity & ageing : I & A·Jul 27, 2023

1. Biological age is associated with hemagglutination inhibition antibody titers in humans (d = 0.16-0.26).

   “advanced BA was associated with improved post-vaccination antibody titres against the different viral types and subtypes. However, this was dependent on both vaccine dose and CMV serostatus”

   Human trialin high-dose vaccine recipientsfour consecutive seasonsn = 292

   Advanced biological age is associated with improved antibody responses in older high-dose influenza vaccine recipients over four consecutive seasons

   Immunity & ageing : I & A·Aug 23, 2022

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1. ILT2+ CD57+ CD56dim NK cell frequency is associated with hemagglutination inhibition antibody titers in humans.

   “frequency of ILT2(+)CD57(+) CD56-Dim natural killer (NK)-cells was positively associated with both plasma IL-6 and post-vaccination A/H3N2 titres”

   Human trialfollow-up cohort of older high-dose recipientsn = 63

   Markers of systemic inflammation are positively associated with influenza vaccine antibody responses with a possible role for ILT2(+)CD57(+) NK-cells

   Immunity & ageing : I & A·May 26, 2022

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1. Inflammation is associated with hemagglutination inhibition antibody titers in humans (d = 0.10-0.45).

   “in older high-dose, but not standard-dose recipients, all systemic inflammatory mediators were positively associated with A/H1N1, A/H3N2 and B titres (d = 0.10-0.45)”

   Human trialhigh-dose inactivated vaccine recipients

   Markers of systemic inflammation are positively associated with influenza vaccine antibody responses with a possible role for ILT2(+)CD57(+) NK-cells

   Immunity & ageing : I & A·May 26, 2022

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1. IL-6 is associated with hemagglutination inhibition antibody titers in humans (Cohen's d = 0.36).

   “IL-6 was positively associated with A/H3N2 titres in young adults (Cohen's d = 0.36)”

   Human trialn = 79

   Markers of systemic inflammation are positively associated with influenza vaccine antibody responses with a possible role for ILT2(+)CD57(+) NK-cells

   Immunity & ageing : I & A·May 26, 2022

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