Human cytomegalovirus lower matrix phosphoprotein 65 (pp65 (also known as UL83))

Human cytomegalovirus lower matrix phosphoprotein 65 (pp65, UL83) is the most abundant tegument protein in the human cytomegalovirus virion, comprising up to 15% of the virion mass[2][3][4][6]. It is a dominant target for both humoral and cellular immune responses, particularly CD8+ T cells, during natural CMV infection[5][7]. The protein plays a key role in antagonizing the host’s innate immune response—specifically, it prevents IRF-3 (interferon regulatory factor 3) from translocating to the nucleus and blocks early induction of the type I interferon pathway, thereby helping the virus evade immediate antiviral defenses[1][8]. The pp65 antigen is frequently used as a marker of ongoing CMV replication in clinical diagnostics and is a leading candidate for monitoring CMV-specific immunity, especially in transplant recipients[5][6][7]. Although it is essential for immune evasion and virion tegument structure, pp65 is non-essential for CMV replication in vitro, and deletion mutants can still form virions, albeit with structural differences[4]. The listing “Cytomegalovirus phosphoprotein 65 antigen-presenting cells activation” is not a canonical molecular target: the protein itself is pp65; “antigen-presenting cells activation” describes an immune process rather than a molecule. Caveat: - is_incorrect=true because the provided target name in the query “Cytomegalovirus phosphoprotein 65 antigen-presenting cells activation” conflates the molecule with an immunological process (antigen-presenting cell activation) rather than denoting a single protein or receptor. The scientifically accurate target is human cytomegalovirus lower matrix phosphoprotein 65 (pp65, UL83).

Other names

pp65UL83HCMV pp65Cytomegalovirus matrix phosphoprotein 65

For immune therapies targeting this protein: - Stimulation of cytotoxic T lymphocyte response against cells expressing pp65 - Vaccine candidates may use pp65 or its peptides to induce protective immunity