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New rationally designed i,i+7-hydrocarbon-stapled peptides that target both HIV-1 assembly and entry have been shown to have antiviral activity against HIV-1 subtypes circulating in Europe and North America. Here, we aimed to evaluate the antiviral activity of these peptides against HIV-1 subtypes predominantly circulating in China.The antiviral activity of three i,i+7-hydrocarbon-stapled peptides, NYAD-36, NYAD-67, and NYAD-66, against primary HIV-1 CRF07_BC and CRF01_AE isolates was evaluated in peripheral blood mononuclear cells (PBMCs). The activity against the CRF07_BC and CRF01_AE Env-pseudotyped viruses was analyzed in TZM-bl cells.We found that all the stapled peptides were effective in inhibiting infection by all the primary HIV-1 isolates tested, with 50% inhibitory concentration toward viral replication (IC50) in the low micromolar range. NYAD-36 and NYAD-67 showed better antiviral activity than NYAD-66 did. We further evaluated the sensitivity of CRF01_AE and CRF07_BC Env-pseudotyped viruses to these stapled peptides in a single-cycle virus infectivity assay. As observed with the primary isolates, the IC50s were in the low micromolar range, and NYAD-66 was less effective than NYAD-36 and NYAD-67.Hydrocarbon-stapled peptides appear to have broad antiviral activity against the predominant HIV-1 viruses in China. This finding may provide the impetus to the rational design of peptides for future antiviral therapy.

To construct a rheumatoid arthritis-specific full-length fully human mammalian display antibody libraries.Peripheral blood lymphocytes were isolated from patients with rheumatoid arthritis. The repertoires of kappa light chain (LCκ) and heavy chain variable region (VH) of the antibodies were amplified by RT-PCR. The amplified LCκ and VH genes were inserted into the vector pDGB-HC-TM separately, and the ligated libraries were transformed into competent E.coli TOPO-10 strain to construct the rheumatoid arthritis-specific antibody heavy and light chain libraries. 293T cells were co-transfected with the libraries and the full-length fully human antibody expressed on the surface of 293T cells were analyzed by flow cytometry.The libraries of rheumatoid arthritis-specific antibody LCκ and heavy chain (IgG1) were constructed. The expression of full-length fully human antibody on the surface of 293T cells was confirmed by flow cytometry. With the rates of correct LCκ and heavy chain sequence insertion reaching 80% and 60%, respectively, as shown by DNA sequence analysis of the randomly selected clones, the libraries showed an expressible combinatory diversity of 6.13×10(10).The constructed libraries provide a useful platform for screening rheumatoid arthritis-specific antibodies.

To construct a mammalian cell surface display library of full-length human antibodies.The total RNA was isolated from human peripheral blood mononuclear cells (PBMCs), and the genes encoding the heavy chain variable regions and kappa light chains (VH and Cκ) of the antibodies were amplified by RT-PCR. The amplified VH and Cκ gene sequences were separately inserted into the vector pDGB-HC-TM. The ligation mixtures were transformed into competent E.coli DH5α cells to construct the antibody libraries, and the library sizes and diversity were analyzed. The library DNAs were transfected into CHO cells and the expression of the full-length human antibodies on the surface of CHO cells was analyzed by flow cytometry.The heavy chain gene library constructed showed a diversity of 2.6 × 10(5), and the kappa light chain gene library had a diversity of 2.0 × 10(5). Sequence analysis of 10 clones randomly selected from the constructed heavy chain gene library and 10 from the light chain gene library showed that 8 heavy chain clones and all 10 light chain clones contained correct open reading frames. Flow cytometry demonstrated that all the 18 clones expressed full-length antibodies, which could be detected on CHO cell surfaces. After co-transfection of the heavy chain and light chain gene libraries into CHO cells, the expression of full-length antibodies on CHO cell surfaces was detected with the positive cells reaching 31.5.A full-length human mammalian display antibody library with a combinatory diversity of 5.2 × 10(10) can be constructed in two weeks, which allows the display of full-length antibodies on mammalian cell surface.

To examine the immunological reactions between the peptides of SARS coronavirus (SARS-Cov) S-protein and the serum of SARS patients for identifying the SARS-Cov epitope.The peptides from S1 domain of SARS-Cov S-protein were synthesized by peptide synthesizer, and the immunological reaction of the peptides with the serum of SARS patients were examined by means of ELISA.The optical density value of the immunological reaction of synthesized 8 peptides with SARS patient serum was 1.5-2.6 times higher than that with normal serum.The 8 peptides from S1 domain of S protein appear to have low immunogenicity to the serum of SARS patients, indicating that these peptides may not be the epitope of the SARS-Cov.