Development, study, and comparison of models of cross-immunity to the influenza virus using statistical methods and machine learning.

Introduction: The World Health Organization considers the values of antibody titers in the hemagglutination inhibition assay as one of the most important criteria for assessing successful vaccination. Mathematical modeling of cross-immunity allows for identification on a real-time basis of new antigenic variants, which is of paramount importance for human health.

Materials And Methods: This study uses statistical methods and machine learning techniques from simple to complex: logistic regression model, random forest method, and gradient boosting.

Antigenic Architecture of the H7N2 Influenza Virus Hemagglutinin Belonging to the North American Lineage.

The North American low pathogenic H7N2 avian influenza A viruses, which lack the 220-loop in the hemagglutinin (HA), possess dual receptor specificity for avian- and human-like receptors. The purpose of this work was to determine which amino acid substitutions in HA affect viral antigenic and phenotypic properties that may be important for virus evolution. By obtaining escape mutants under the immune pressure of treatment with monoclonal antibodies, antigenically important amino acids were determined to be at positions 125, 135, 157, 160, 198, 200, and 275 (H3 numbering).

[Mathematical model for assessing the level of cross-immunity between strains of influenza virus subtype HN].

Introduction: The WHO regularly updates influenza vaccine recommendations to maximize their match with circulating strains. Nevertheless, the effectiveness of the influenza A vaccine, specifically its H3N2 component, has been low for several seasons. The aim of the study is to develop a mathematical model of cross-immunity based on the array of published WHO hemagglutination inhibition assay (HAI) data.

[Monoclonal antibodies to hemagglutinin of influenza A/H7N3 virus (Orthomyxoviridae: Alphainfluenzavirus: Influenza A virus)].

Introduction: Variants of influenza virus A/H7 have the same high pandemic potential as A/H5. However, the information about the antigenic structure of H7 hemagglutinin (НА) is considerably inferior in quantitative terms to similar data for H5 НА.The aims of the study were development and characterization of the monoclonal antibodies (MAbs) panel for HA subtype H7 of the influenza A virus.

Pleiotropic effects of hemagglutinin amino acid substitutions of influenza A(H1N1)pdm09 virus escape mutants.

In the present study we assessed pleiotropic characteristics of the antibody-selected mutations. We investigated pH optimum of fusion, temperatures of HA heat inactivation, in vivo and in vitro replication kinetics, and connectivity with panel of sera of survivors patients in different epidemic seasons of the previously obtained influenza H1 escape mutants. Our results showed that N133D (H3 numbering) mutation significantly lowered the pH of fusion optimum.