recombinant human interferon alfa-2a

Rapid and robust immune response boosting with potent, next-generation adjuvant in viral vector-primed primates.

King Hannah A D HAD, Subra Caroline C, Tourtellott Emily E, Swafford Isabella I et al.

To identify strategies for augmenting vaccine immunogenicity, we compared a pox-protein prime-boost regimen comprising recombinant modified vaccinia virus Ankara and multimeric HIV-1 Env gp145, adjuvanted with Army Liposomal Formulation (ALF) either adsorbed to aluminum salt (ALFA) or formulated with the QS-21 saponin (ALFQ), in rhesus macaques. ALFQ promoted greater magnitude and more durable humoral and cellular immune responses than ALFA, which exhibits similar immunogenicity to aluminum-based adjuvants. Peak Env-specific CD4+ T cell responses assessed by intracellular cytokine staining were 10-fold greater with ALFQ, and CD8+ T cell responses were unexpectedly robust, averaging greater than 1%. ALFQ induced higher levels of several immunostimulatory cytokines in plasma, which correlated with adaptive immune responses. However, vaccination did not protect against heterologous intrarectal challenge with transmitted/founder SHIV-CH505. We provide evidence that CH505 Env may maintain a relatively closed conformation, rendering it less susceptible to targeting by Fc-mediated antibody functions. Overall, ALFQ is a promising adjuvant to improve antibody and T cell response magnitude.IMPORTANCEAn effective and durable vaccine preventing HIV-1 acquisition is urgently needed to end the HIV-1 pandemic. To date, of the nine vaccine efficacy trials conducted in humans, only the RV144 vaccine trial demonstrated efficacy in reducing infections, although immune responses waned rapidly. We evaluated a modified HIV-1 vaccine regimen incorporating next-generation adjuvants to improve immune responses and vaccine efficacy in a gold standard, pre-clinical primate model. Adjuvanted protein boosting markedly increased antibody, T cell, and pro-inflammatory response magnitude. These data, combined with the adjuvant's strong safety and immunogenicity track record in clinical trials, indicate that novel adjuvants represent a promising strategy for improving immune responses to protein immunogens. Future vaccine regimens against HIV-1 and other pathogens for which eliciting robust immunity has been difficult may benefit from incorporating these or related next-generation adjuvants.

Methodological Considerations in the Bioequivalence Assessment of Recombinant Human Serum Albumin [Letter].

Chang Peng P, Shen Danfeng D

Immunogenicity of a Candidate Hepatitis C Vaccine Based on Non-Structural DNA-Protein Sequences and a Novel Complex Adjuvant.

Masalova Olga V OV, Lesnova Ekaterina I EI, Kozlov Vyacheslav V VV, Valuev-Elliston Vladimir T VT et al.

Global elimination of hepatitis C virus (HCV) infection requires not only direct-acting antivirals (DAAs) but also the development of a highly effective prophylactic and/or therapeutic vaccine. Background/Objectives: Our aim was to optimize the composition of the candidate vaccine against HCV by combining recombinant non-structural proteins and a DNA construct with a complex adjuvant. Methods: C57BL/6 and DBA/2J mice were immunized three times at 2-week intervals using different schemes. The viral antigens consisted of a mixture of NS3, NS5A, and NS5B proteins and/or recombinant DNA expressing NS3-NS5B polyprotein. As adjuvants, a complex adjuvant, a mixture of Polymuramil® and Pyrogenalum® (NOD1/NOD2 and TLR-4 agonists), or a CpG ODN adjuvant (TLR-9 agonist) were used. Results: The most efficient regimen was three subcutaneous administrations of the combined DNA, recombinant protein components, and a new complex adjuvant. This scheme elicited a robust immune response, characterized by high antibody titers, enhanced antigen-specific lymphocyte proliferation, and significant interferon-gamma (IFN-γ) secretion in both mouse lines. Furthermore, the complex adjuvant outperformed CpG ODN in stimulating both humoral and cellular immunity against the HCV antigens. The vaccine composition stimulated the formation of CD4+ memory T cells and decreased the relative frequences of suppressive Treg and MDSCs. Conclusions: The presented candidate vaccine induces a strong immune response to HCV proteins. The next step would be to validate the protective effect in cell culture and animal models. This would one the path to preclinical studies of this vaccine composition.

Genome-Wide Characterization of Recombinant AAV6 Vector Integration in Human CD34＋ Cells.

Lee Hyeon Jeong HJ, Park Nayoung N, Park In-Byung IB, Kang Seok-Jin SJ et al.

Several viral vectors have been developed for gene therapy due to their high transduction efficiency, but some integrate into the host genome, raising safety concerns. Recent studies have identified recombinant adeno-associated virus serotype 6 (rAAV6) as a promising vector for hematopoietic stem and progenitor cell-targeted gene therapy because of its non-pathogenic nature, low integration frequency, and capacity for sustained episomal transgene expression. Nevertheless, its chromosomal integration profile remains incompletely defined, warranting a comprehensive evaluation to assess long-term safety. In this study, human CD34＋ cells were transduced with rAAV6 under varying vector doses and transgene contexts, and integration-site mapping was performed using the integration-site enriched library sequencing approach. Consistent with the largely episomal nature of AAV, high vector sequence alignment rates were observed across all groups. rAAV6 integrations occurred randomly throughout the genome, showing a broad pan-chromosomal distribution without evidence of sequence-specific targeting or clustering. Although integrations were more frequent in CpG islands, commonly located within open chromatin, this pattern likely reflects chromatin accessibility rather than targeting bias. Functional enrichment analysis indicated associations with general cellular and structural processes, without enrichment in oncogenic pathways. Distance-based analysis confirmed that integration sites were mapped at a distance from oncogenes and tumor suppressor genes, even under high-dose conditions. The data support the genomic safety of rAAV6 and its applicability to hematological gene therapy.