Overview of Parvovirus
Parvovirus usually refers to the Parvoviridae family, which is a collection of more than 100 species of small DNA viruses divided into 23 genera of 3 subfamilies. Among these species, parvovirus B19 (also known as Primate erythroparvovirus 1 or erythrovirus B19, B19V) was the first identified and the best-characterized human pathogen belonging to the genus of Erythroparvovirus.
The discovery of B19V dated back to 1975 when virologist Yvonne Cossart was screening the hepatitis B virus. B19V is highly contagious all over the world with no ethnic or geographical boundaries, which is the main cause of the erythema infectiosum (fifth disease), chronic anemia in the immunocompromised host, and hydrops fetalis. In most cases, B19V is transmitted through the respiratory tract. Diagnosis of human B19V infections primarily depends on several approaches, quantitative polymerase chain reaction (PCR) assays, in situ hybridization, and enzyme-linked immunosorbent assay (ELISA) for parvovirus antibodies detection.
Parvovirus Virology
Generally, parvovirus is a family of the small, non-enveloped virus with ~20–30 nm in diameter. Inside the parvovirus particle is a linear, nonsegmented, single-stranded DNA genome, including two major gene complexes. One is the Rep gene on the left side of the genome encoding the non-structural protein, which is responsible for parvovirus replication, the other is the Cap gene on the right encoding two capsid proteins (VP1 and VP2). About 60 copies of the capsid proteins (VP1 and VP2) make up the capsid of the parvovirus, assembling into an icosahedral symmetry. The larger VP1 (83 KD) accounts for about 5% of total capsid proteins, which contains the recognition epitopes of the immune system. The smaller VP2 (58 kD) comprises approximately 95% capsid proteins.
Fig.1 Parvoviruses are symmetrical icosahedral particles. (Broliden, 2006)
Possible Pathogenesis of Anemia Caused by Parvovirus
The pathogenesis of parvovirus is mainly related to the immune response of the body. Take B19V as an example, which has a specific tropism for erythroid progenitor cells in the bone marrow. It has been demonstrated that B19V agglutinate human red cells by directly binding to the hemagglutinin, a glycolipid globoside (also called P antigen), which also functions as the receptor on erythroid progenitor cells. After invasion, replication, and assembly of B19V in these cells, the erythropoiesis is blocked. In healthy individuals, the transient block erythropoiesis won’t affect hemoglobin levels due to the long life span of red blood cells, but in immunocompromised patients, this B19V infection leads to aplasia.
Fig.2 B19V infection of human erythroid progenitor cells (B19V life cycle). (Qiu, 2017)
Parvovirus Antibody in Creative Biolabs
For the needs of scientific research and laboratory diagnostic assays, Creative Biolabs has developed a spectrum of monoclonal and polyclonal antibodies targeting parvovirus and its capsid proteins VP1 and VP2. More importantly, high-quality custom antibody products and services based on clients’ demands are also within our scope.
For specific parvovirus antibody products, please directly contact us. We will reply to you within 24 hours.
References
- Cossart, Y.E., et al. Parvovirus-like particles in human sera. The Lancet. 1975, 305(7898): 72-73.
- Broliden, K., et al. Clinical aspects of parvovirus B19 infection. Journal of Internal Medicine. 2006, 260(4): 285-304.
- Qiu, J., et al. Human parvoviruses. Clinical Microbiology Reviews. 2017, 30(1): 43-113.
