EBV Antibodies and the Risk of Associated Malignancies
EBV Antibodies and the Risk of Associated Malignancies
For NPC, we considered the evidence of an association between EBV serological markers (i.e., anti-EBV antibodies) measured before disease onset and the development of cancer to be strong. Therefore, an exhaustive literature review was not conducted, but key prospective studies were highlighted.
In contrast, the evidence for the other 4 EBV-associated malignancies was not considered conclusive, so we conducted an exhaustive literature review using combinations of the following search terms for each malignancy: "cancer x" and "EBV serology or EBV antibodies or EBV immune response." This keyword search was performed in PUBMED and was restricted to English-language articles published after 1980.
Results generated through this keyword search are reported with an emphasis on 2 characteristics: 1) EBV proteins targeted and 2) antibody type. The EBV proteins targeted included structural proteins expressed during the lytic cycle, such as viral capsid antigen (VCA). Nonstructural proteins were also targeted, including both those crucial for viral genome maintenance inside latently infected cells, such as EBV-nuclear antigen (EBNA), and those expressed during the intracellular switch from latent phase to lytic viral replication, such as early antigen (EA) and ZEBRA.
The antibody types highlighted include immunoglobulin G (IgG) and IgA. IgG antibodies are the most abundant form of antibodies produced by plasma cells in response to exposure to infectious agents and typically reflect cumulative exposure to EBV. IgA antibodies are produced at mucosal surfaces and are thought to be markers of more recent exposure in these compartments, such as the oral or nasopharyngeal epithelium.
Methods
For NPC, we considered the evidence of an association between EBV serological markers (i.e., anti-EBV antibodies) measured before disease onset and the development of cancer to be strong. Therefore, an exhaustive literature review was not conducted, but key prospective studies were highlighted.
In contrast, the evidence for the other 4 EBV-associated malignancies was not considered conclusive, so we conducted an exhaustive literature review using combinations of the following search terms for each malignancy: "cancer x" and "EBV serology or EBV antibodies or EBV immune response." This keyword search was performed in PUBMED and was restricted to English-language articles published after 1980.
Results generated through this keyword search are reported with an emphasis on 2 characteristics: 1) EBV proteins targeted and 2) antibody type. The EBV proteins targeted included structural proteins expressed during the lytic cycle, such as viral capsid antigen (VCA). Nonstructural proteins were also targeted, including both those crucial for viral genome maintenance inside latently infected cells, such as EBV-nuclear antigen (EBNA), and those expressed during the intracellular switch from latent phase to lytic viral replication, such as early antigen (EA) and ZEBRA.
The antibody types highlighted include immunoglobulin G (IgG) and IgA. IgG antibodies are the most abundant form of antibodies produced by plasma cells in response to exposure to infectious agents and typically reflect cumulative exposure to EBV. IgA antibodies are produced at mucosal surfaces and are thought to be markers of more recent exposure in these compartments, such as the oral or nasopharyngeal epithelium.