Human HPV 16 L1-capsids IgG ELISA Kit

Human papillomaviruses (HPVs) are a group of small, envelope-less DNA viruses, 52-55 nm in diameter, a population that includes more than 450 genotypes (types) with more than 10% DNA sequence variation in the most conserved L1 open reading frames (ORFs). HPV infections can lead to benign tumors or cancers. HPV can be classified into low-risk and high-risk types based on their relevance to cancer, with HPV16 and HPV18 being the two most common high-risk HPVs, and about 70% of all HPV-related cervical and head and neck cancers are caused by HPV 16 and HPV 18. Different from low-risk HPV, high-risk HPV expresses two powerful oncoproteins E6 and E7, which mediate the degradation of p53 and pRb (two tumor suppressor proteins essential for cell cycle control and genomic stability), respectively, leading to HPV-induced carcinogenesis. HPV 16 and HPV 18 are associated with 70% of moderate cervical intraepithelial neoplasia (CIN 2 or higher). HPV 16 accounts for 87% of squamous carcinomas, while HPV 18 accounts for 86% of adenocarcinomas.

Papillomavirus contains a double-stranded circular DNA genome about the size of 8kb. All papillomavirus genomes can be divided into three distinct regions: upstream regulatory region (URR), early (E) and late (L) gene regions by two polyadenylated (pA) signals, namely, early (pA_E) and late (pA_L). The URR region does not encode any protein, also known as the long control region (LCR). The URR of different papillomaviruses varies in size, and HPV 16 is 853bp. HPV URR contains binding sites of viral E1 and E2 proteins that initiate HPV replication, as well as several cellular transcription factors used to initiate transcription, including NFI, Oct-1 (OCT), AP-1, TEF-1 (TF1) and SP1. URR also contains a replication source (Ori) that is essential for papillomavirus replication, which is highly homologous to mammalian autonomous replication conserved sequence (ACS).

Figure 1. Genome structure of HPV 16
(Source: Yu L, et al. 2022)

To initiate viral infection, the L1 capsid protein binds to heparan sulfate proteoglycans (HSPGs) located on the surface of epithelial cells or basement membranes, or interacts with laminin-332 on the extracellular matrix, and upon binding, the viral capsid undergoes a conformational modification mediated by cyclophilin (CyP) B, ultimately exposing the minor capsid protein L2. The HPV 16 gene encoding L1 capsid protein lies between 5559 and 7154 nucleotides, with a size of 531 amino acids. The L1 sequence similarity between the HPV 16 mutant and the virus genome reference sequence is more than 98%. It is worth noting that the non-synonymous mutation of the L1 gene is located near the neutralizing epitope, increasing the probability of evading immune response. The current design of HPV vaccines is based on virus-like particles (VLP), which are produced by the major capsid protein L1 and mimic the structure of virions. Vaccination of HPV vaccine can produce high quality and long-term antibody titers, most of which are immunoglobulins (IgG) specific to the corresponding HPV L1 proteins. Creative Diagnostics is here to provide you with HPV 16 L1-capsids IgG ELISA kit that can qualitatively detect the IgG concentration of HPV 16 L1 capsid protein in human serum and plasma.

Human papillomavirus type 16 L1-capsids IgG ELISA
Human papillomavirus 16 L1-capsids IgG ELISA
HPV 16 L1-capsids IgG ELISA