CMV Pp65

Human Cytomegalovirus (HCMV), a member of the herpesvirus family, is a significant pathogen that can cause severe disease in immunocompromised individuals, such as transplant recipients and individuals with HIV/AIDS. One of the key proteins involved in the immune response to HCMV is the phosphoprotein 65 (pp65), encoded by the UL83 gene. This protein is a major component of the viral tegument and plays a crucial role in modulating the host immune response.

The pp65 protein is a 65 kDa phosphoprotein that is abundantly expressed during the late phase of the HCMV replication cycle. It is involved in the assembly and release of the virus and is a major constituent of the dense bodies, which are non-infectious particles produced during HCMV infection . The protein contains immunodominant regions that are recognized by the immune system, making it a key target for immune responses.

Recombinant pp65 is typically produced using Escherichia coli (E. coli) expression systems. The recombinant protein contains the immunodominant regions of pp65, specifically amino acids 297-510, and is often fused to a glutathione S-transferase (GST) tag to facilitate purification . The recombinant pp65 protein is used extensively in research and diagnostic applications, including enzyme-linked immunosorbent assays (ELISA) and Western blots, due to its high immunoreactivity and minimal specificity problems .

The preparation of recombinant pp65 involves cloning the UL83 gene into an expression vector, which is then introduced into E. coli cells. The bacteria are cultured, and the expression of the recombinant protein is induced. The protein is then purified using chromatographic techniques, often involving the GST tag for affinity purification . The purified protein is then used in various applications to study the immune response to HCMV and to develop diagnostic assays.

The pp65 protein plays a significant role in modulating the host immune response. It has been shown to prevent the activation of interferon response factor 3 (IRF-3), thereby inhibiting the interferon response, which is a crucial part of the antiviral defense mechanism . This ability to modulate the immune response makes pp65 a key target for studying the interactions between HCMV and the host immune system.

Recombinant pp65 is widely used in research to study the immune response to HCMV. It is also used in the development of vaccines and diagnostic assays. The protein’s ability to elicit strong immune responses makes it a valuable tool for understanding HCMV pathogenesis and for developing strategies to prevent and treat HCMV infections .