logo ban ban logo

Učit se znamená objevovat to, co už víš.
Konat znamená demonstrovat, že to to víš.
Učit druhé znamená připomínat jim, že to vědí stejně dobře jako ty.
Všichni jste zároveň žáci, praktikanti a učitelé.

Richard Bach

mendel

Výzkum

Beads based electrochemical assay for detection of influenza hemagglutinin labelled with cdte quantum dots

These days are characterized by rapid growing of population, international trade and globalization, and for this reason the risk of influenza pandemic origination becomes larger and larger [1]. Influenza is one of the most frequently occurred respiratory diseases, which cause app. 500,000 deaths every year. Influenza virus is subject to genetic mutation, mainly due to the lack of proof-reading activity of its polymerase [2]. Influenza infections are mostly located into the seasonal epidemics or less frequently influenza pandemics. During twentieth century there were three, with shortening delay: Spanish flu in 1918, Asian flu in 1957 and Hong-Kong flu in 1968. Twenty first century is also marked by a few cases of pandemics (Swine and Avian influenza) with a small number of victims, but with larger economic impact. Antigenic drift results from an accumulation of point mutations leading to minor antigenic changes, while antigenic shift involves major antigenic changes by introduction of new hemagglutinin (HA) and/or neuraminidase (NA) subtype into human population [2]. Combinations of HA (1-17) and NA (1-9) subtypes affect biological properties of influenza viruses, especially host range and virulence. HA is responsible for the initiation infection and it binds sialic acid on the host cell surface. NA removes sialic acid from host receptor and thus enables releasing the replicated virion [3,4]. Sialic acids (SAs) are located on the terminal positions of glycan on the host cell surface, which is important in the spread of pathogen [5,6].

Vaccination is the most effective way of prevention influenza epidemics and the pandemic emergence [7-9], however, influenza vaccine is effective only one year, because the limiting factors are antigens mutational changes, which cause that reuse of the last year vaccine would not be effective [10]. In 2006, World Health Organization (WHO) published an action plan to increase the current supplies of influenza vaccine. One of the goals was to reach 2,340 million monovalent doses produced in the case of a global pandemic, which highlights the need to develop new technologies capable to support urgent and large demands for vaccines. Current global influenza vaccine production capacity, which is concentrated primarily in nine industrialized countries, is estimated at 350 million doses per year of trivalent (15 µg per hemagglutinin antigen) vaccine, conferring protection against two influenza A strains and one influenza B strain [8,11] and are given parenterally to induce serum anti-HA antibody for prevention of subsequent infection and illness from natural influenza [8]. Inactivated vaccines induce protective levels of serum antibodies to influenza HA surface proteins [9] and is regarded as the most effective prophylactic method. Before the presentation of the influenza vaccine at pharmaceutical market it is necessary, especially for the human immunization, rapid and sensitive analysis of vaccination antigens. As a detection system, electrochemical biosensors and bioassays have attracted considerable interest due to their high performance, miniaturized construction, and low costs [12-15]. In spite of the fact that quantum dots (QDs) are currently utilized especially for in vivo and in vitro imaging, their application in field of biosensing devices for influenza viruses could be also considered [16]. In this study we describe two-steps assay for isolation and detection of influenza vaccine hemagglutinin. The isolation process is based on glycan modified paramagnetic particles (MPs) and specific and selective binding between glycan and HA.

Práce je spojená s projektem CEITEC CZ.1.05/1.1.00/02.0068

Zemědělská 1/1665
613 00 Brno
Budova D		Tel.: +420 545 133 350
Fax.: +420 545 212 044