H1N1 HA Specific Neutra™ Antibody Products
Product listInfluenza A virus subtype H1N1 is a type of influenza virus responsible for the 2009 swine flu pandemic. It is an RNA virus characterized by a segmented genome, enabling high variability. Its structure includes a lipid envelope with surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). H1N1 causes respiratory illness with symptoms like fever, cough, and fatigue. Severe instances might cause pneumonia and respiratory failure. Transmission occurs person-to-person by respiratory droplets, making it extremely infectious. H1N1 HA, a key surface protein, is required for virus's ability to enter host cells. It undergoes significant antigenic variation, impacting vaccine effectiveness and immune response.
H1N1 Infection
H1N1 infection initiates a complicated interplay between viral invasion and host immune defense. H1N1 infection begins with inhalation of virus-laden droplets. Upon entry, the virus targets respiratory epithelial cells, causing cellular damage and triggering an inflammatory cascade. This results in tissue changes such as epithelial cell shedding, increased mucus production, and, in severe cases, alveolar damage leading to pneumonia. Concurrently, the immune system springs into action. The innate response releases cytokines, initiating inflammation, while dendritic cells activate the adaptive arm. This leads to the production of H1N1-specific antibodies, crucial for viral neutralization, and cytotoxic T cells, which eliminate infected cells. The balance between viral replication and the strength of the immune response determines the severity of the infection, with factors like pre-existing immunity and overall health playing significant roles.
H1N1 HA Structure
The HA of H1N1 is a trimeric glycoprotein. Each monomer comprises two subunits, HA1 and HA2, formed by proteolytic cleavage. HA1 forms the globular head, containing the receptor-binding site (RBS) for sialic acid. HA2 forms the stalk region, crucial for membrane fusion. The trimer's structure is stabilized by disulfide bonds and hydrophobic interactions. The RBS exhibits variability due to mutations, impacting receptor specificity and antibody binding. The structure of HA is essential for its function in viral entry and is a primary target for neutralizing antibodies.
Fig. 1 HA protein structure.1, 3
H1N1 HA Function
The primary function of H1N1 HA is to mediate viral entry into host cells. HA interacts with sialic acid receptors on the host cell's surface, initiating endocytosis. Following endocytosis, the acidic conditions of the endosome trigger a conformational shift in HA, particularly in the HA2 subunit. This change leads to the fusion of the viral and host cell membranes, releasing the viral RNA into the cytoplasm. HA's receptor-binding specificity determines host diversity and tissue tropism. The protein's antigenic variability allows the virus to evade host immune responses. HA is also a key target for vaccine development, as neutralizing antibodies against HA can prevent infection.
H1N1 HA Neutralizing Antibodies
Antibodies targeting H1N1 HA are critical for neutralizing the virus and avoiding infection. These antibodies can block HA's binding to sialic acid receptors, preventing viral entry. Some antibodies target the HA stalk region, inhibiting membrane fusion. Neutralizing antibodies can be generated through vaccination or natural infection. Broadly neutralizing antibodies (bnAbs), which target conserved areas of HA, offer protection against multiple influenza strains. The diversity of the HA head region necessitates periodic vaccination updates to match the circulating strains. Antibody-based therapeutics, like monoclonal antibodies, are developed to treat severe H1N1 infections.
Fig. 2 The bnAbs targeting HA.2, 3
Creative Biolabs offers more than 20 types of proven, high-quality anti-H1N1 HA neutralizing antibody products, ensuring reliable and accurate research results.
REFERENCES
- Ghafoori, Seyed Mohammad, et al. "Structural characterisation of hemagglutinin from seven Influenza A H1N1 strains reveal diversity in the C05 antibody recognition site." Scientific Reports 13.1 (2023): 6940.
- Biswas, Mrityunjoy, et al. "Broadly neutralizing antibodies for influenza: passive immunotherapy and intranasal vaccination." Vaccines 8.3 (2020): 424.
- Distributed under Open Access license CC BY 4.0, without modification.
