![]() ![]() An additional region encodes for five V3 loops from HIV isolates CC, RF, MN, RU, and IIIB, were designed along with linkers between each V3 epitope. coli-based expression, the C4V3 encoding gene reported by Varona-Santos et al. The antigenic properties of the C4(V3)6 protein are also presented herein. coli and subsequently in transgenic both tobacco and lettuce plants in an effort to develop a low-cost production/delivery system (Rosales-Mendoza et al. This molecule was initially produced in recombinant E. In this study, we have expanded the configuration of this polypeptide to include five additional V3 loop regions from different HIV isolates to yield a protein molecule designated as C4(V3)6. Thus, using this C4V3 polypeptide configuration to develop new molecules eliciting enhanced immune responses is worthy of consideration in further studies. More recently, this functional polypeptide has been produced into tobacco chloroplasts, and transplastomic tobacco carrying this peptide has proven to elicit oral immunogenicity in test mice (Rubio-Infante et al. Previously, we have reported on the production and immunological characterization of a rC4V3 hybrid polypeptide carrying sequences from the fourth conserved (C4) and the third variable (V3) domains of the glycoprotein gp120 MN, as this polypeptide is a strong elicitor of anti-HIV antibodies at systemic and mucosal compartments without the need for adjuvants (Varona-Santos et al. The inclusion of a number of protective epitopes within a single molecule may elicit appropriate cellular and humoral responses that can overcome evasive problems of viral mutations. This allows for production of larger amino acid sequences that are likely to be immunogenic and less expensive than their synthetic counterparts. Through genetic engineering efforts, not only it has been possible to produce recombinant proteins, but also to design specific protein configurations containing several neutralizing epitopes in a single formulation (Lu et al. Hence, recombinant proteins serve as viable alternatives. In addition, large-scale synthesis of long peptides is not economically feasible for large scale vaccination programs, especially in the developing world. Thus, coupling a carrier to a synthetic peptide is essential for enhancing stability and increasing immunogenicity of such a peptide (Haynes et al. ![]() In this context, it is important to point out that, oftenly, synthetic peptides tend to be weak immunogens, and are chemically unstable. ![]() Moreover, these HIV peptide-based candidates have shown to induce neutralizing antibodies, of broad spectrum, against primary isolates (Haynes et al. Interestingly, polyvalent synthetic peptides have proven to be immunogenic, leading to both humoral and cellular responses in both mice and non-human primates (Hart et al. Other effective approaches are based on chemical coupling of these peptides to a wide variety of carriers (Hamajima et al. Previous studies have demonstrated that humoral and cellular immune responses can be elicited by both liposomes and immunostimulatory complexes (ISCOMs) formulated with HIV-1 peptides when an appropriate adjuvant is used (Agrawal et al. This allows for immunization against non-immunodominant epitopes, as well as those epitopes surrounded by several non-protecting antigens (Fernández et al. 2012).Īmong several approaches explored to date against HIV, synthetic peptides have demonstrated to be promising components of HIV vaccine formulations as these are designed to include specific epitopes (Rerks-Ngarm et al. This is primarily attributed to the rapid mutation ability of the virus which facilitates viral elusiveness from the host’s cellular and humoral immune responses (Nabel et al. However, this has been a challenge as current vaccination strategies that prevent viral infections such as those for smallpox, hepatitis B, and polio have been ineffective in preventing HIV infection. The development of an effective vaccine against the human immunodeficiency virus (HIV) that causes acquired immune deficiency syndrome (AIDS) remains a priority in global health initiatives. ![]()
0 Comments
Leave a Reply. |