Carboxyl Terminus Truncated Human Papillomavirus Type 58 L1 Protein Maintains Its Bioactivity and Ability to Form Virus-like Particles

Summary: To prepare carboxyl terminus truncated human papillomavirus type 58 L1(HPV58L1) protein and evaluate its ability to form virus-like particles, the baculovirus and Sf-9 insect cells was used to express HPV58L1 protein, and pFastBac-Htb containing HPV58L1 gene sequence of carboxyl terminus truncation was generated. Then Sf-9 cells were infected with recombinant baculovirus. After being cultured, the post-infected cells expressing-HPV58L1 protein-were harvested and analyzed by SDS-PAGE and Western blot. The ProBond~TM purification system was used for protein purification. The bio-activity of purified protein was identified by mouse erythrocyte hemagglutination assay, and the VLP formation was examined with transmission electron microscope. Our results showed that the recombinant baculovirus was generated and the Sf-9 cells was infected with the recombinant baculovirus, and after collecting, total cellular proteins were extracted. Truncated HPV58L1 protein with MW 58KD was revealed by SDS-PAGE and confirmed by Western blot. The purified L1 proteins under native condition could cause mouse erythrocytes to agglutinate and form VLP. It is concluded that HPV58L1 protein with carboxyl terminus truncation could be efficiently expressed. In baculovirus Sf-9 cells expression system, the purified protein could self-assemble into virions in vitro, and induce agglutination of mouse erythrocytes, indicating that carboxyl terminus truncation does not interfere with the bioactivity of HPV58L1 protein.

Novel heat shock protein Hsp70L1 activates dendritic cells and acts as a Th1 polarizing adjuvant

Heat shock proteins (HSPs) are reported to act as effective adjuvants to elicit anti-tumor and anti-infection immunity. Here, we report that Hsp70-like protein 1 (Hsp70L1), a novel HSP derived from human dendritic cells (DCs), has potent adjuvant effects that polarize responses toward Th1. With a calculated molecular weight of 54.8 kDa, Hsp70L1 is smaller in size than Hsp70 but resembles it both structurally and functionally. Hsp70L1 shares common receptors on DCs with Hsp70 and can interact with DCs, promoting DC maturation and stimulating secretion of the proinflammatory cytokines interleukin 12p70 (IL-12p70), IL-1beta, tumor necrosis factor-alpha (TNF-alpha), and the chemokines IP-10, macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, and normal T cell expressed and secreted (RANTES). The induction of interferon-gamma-inducible protein 10 (IP-10) secretion by Hsp70L1 is not shared by Hsp70, and other functional differences include more potent stimulation of DC IL-12p70, CC-chemokine, and CCR7 and CXCR4 expression by Hsp70L1. Immunization of mice with the hybrid peptide Hsp70L1-ovalbumin(OVA)(257-264) induces an OVA(257-264)-specific Th1 response and cytotoxic T lymphocyte (CTL) that results in significant inhibition of E.G7-OVA tumor growth. The ability of Hsp70L1 to activate DCs indicates its potential as a novel adjuvant for use with peptide immunizations; the Hsp70L1 antigen peptide hybrid may serve as a more effective vaccine for the control of cancer and infectious diseases.

Research Progress of HPV L1 Capsid Protein in Prediction of Cervical Lesions

Cervical cancer is one of the most common malignant gynecological tumors and has the second highest incidence of all malignancies in females.Chronic and persistent infection with High Risk Human Papillomavirus(HR-HPV)is the main cause of cervical cancer.There is a distinct lack of methodology by which to determine whether cervical epithelial dysplasia is cancerous following HPV infection.HPV L1 capsid protein is a major structural protein of human papillomavirus(HPV),and it is the main target of the local cellular immune response aiming to combat human papillomavirus after HPV infection within cervical cells.Greater understanding of HPV L1 capsid protein and its association with cervical cytology,histopathology,patient age and human papillomavirus viral load has the potential to contribute toward improved the diagnosis and management of cervical cancer,providing useful information for gynecological clinicians in the hope of improving patient treatment and quality of life.This article reviews the predictive utility of HPV L1 capsid protein for cervical lesions.

MAPPING EPITOPES OF HUMAN PAPILLOMAVIRUS TYPE 16 L1 PROTEIN WITH A PHAGE DISPLAY EPITOPE LIBRARY

The objective of this study is to map epitopes on HPMAPV16 L1 protein and provide information to the design of HPV16 prophylactic peptide vaccine. The epitopes on L1 protein were screenedby polyclonal and two monoclonal antibodies (BS and F4G3) against RPV16 L1 protin from a 6-merfd phage display epitope library with the method or immuuo-afrinity screening (Biopauuing). Aferthree rounds or Bio-Panning, the Positive phages were detected by L1 antibodies again with ELISA.The positive phages reacted strongly with L1 antibodies were then identified by DNA sequencing.Three mimotopes have been screened by polycloual and two monoclonal antibodies. The mimotope(LSLFSC) reacted with mouoclonal antibody B8 showed 50% pomology with the sequence 270275a. a (DSLFFY) of prototype HPV16 L1. Another mimotope (LTSSYS) reacted with polyclonalantibodies had 66% pomology with the L1 sequence 516~521a. A(TTSSTS), also a mimotope (DRWDRF) was found had the bomologic RF with the known L1 sequence 441 ~446a. a. The mimotopesLSLFSC and DRWDRF were adjacent to the epitopes at 267~269a. a and 422~441 a. a reported byother researchers Previously. Our results suggest that there might be a batch of epitopes on HPV16L1 ppotein, and the predominant epitopes of HPV16 L1 protein are located in the above two domains. These results will be helpful for design or HPV16 prophylactic peatide vaccines and HPVpolyvalent vaccines.

Four and a half LIM domains protein 1 can be as a double-edged sword in cancer progression

Four and a half LIM domains protein 1(FH L1),as the name suggests,contains four and a half LIM domains capable o f interacting with various molecules,including structural proteins,kinases,and transcriptional machinery.FHL1 contains a zinc-finger domain and performs diverse roles in regulation of gene transcription,cytoarchitecture,cell proliferation,and signal transduction.Several studies have validated the importance of FHL1 in muscle development,myopathy,and cardiovascular diseases.Mutations in the FHL1 gene are associated with various myopathies.Recently,FHL1 was identified as a major host factor for chikungunya virus(CHIKV)infection in both humans and mice.Based on more recent findings over the last decade,FHL1 is proposed to play a dual role in cancer progression.On the one hand,FHL1 expression is suppressed in several cancer types,which correlates with increased metastatic disease and decreased survival.Moreover,FHL1 is reported to inhibit tum or cell growth and migration by associating with diverse signals,such as TGF-P and ER,and therefore considered a tumor suppressor.On the other hand,FHL1 can function as an oncogenic protein that promotes tumor progression upon phosphorylation,reflecting complex roles in cancer.This review primarily focuses on the dual role and underlying mechanisms of action of FHL1 in human cancer progression and its clinical relevance.