Advances in Vaccine Development for Human Lymphatic Filariasis

Abstract

According to the World Health Organization, currently, over 880 million people are at risk of acquiring the lymphatic filariasis (LF) infection in over 52 countries worldwide. Current approaches to control LF by 2020 are reaching short of its anticipated goal. Several studies suggest the existence of protective immunity against LF in the human. Thus, it is possible to develop a prophylactic vaccine against LF infections in the human. Several potential vaccine candidates were identified and tested for their vaccine potential against LF. Preclinical studies to date suggest that it is possible to develop a prophylactic vaccine against LF. Much work needs to be done, but it is clear that a prophylactic vaccine combined with targeted chemotherapy is critically required for eliminating LF worldwide.

The potentials of Calotropis procera against filarial elephantiasis: an in-silico approach

“…Mass Drug Administration (MDA) is controlling the disease to an extent (Kalyanasundaram et al 2020).…”

Highlighting the Relevance of CD8+ T Cells in Filarial Infections

“…Prophylactic anti-filarial vaccines, replacing or combined with drug therapies, are required to effectively eliminate filarial infections worldwide ( 81 , 82 ). The search for vaccine candidates for filarial infections has been progressive over the years (reviewed in 81 – 83 ), although there are currently no approved consumable vaccines available for filariasis.…”

“…The majority of immunization trials against filarial infections in experimental models demonstrate induction of IL-2, IL-4, IL-10, IL-17, and IFN-γ, indicating a balanced Th1/Th2 immunity ( 85 – 90 ). The efficacy of these potential vaccine candidates in different animal models ranges from 45% to 94% ( 83 ). The vaccine formulations usually include filarial antigens such as heat shock protein 12.6 ( 86 – 88 ), abundant larval transcript-2 ( 86 , 88 , 89 , 91 ), tetraspanin large extracellular loop ( 86 – 88 ), vespid allergen homologue ( 89 , 91 ), thioredoxin peroxide ( 86 ), calponin ( 92 ), disorganized muscle protein-1 ( 93 ), and trehalose-6-phosphate phosphatase ( 35 ).…”

“…Given this, a very plausible therapeutic approach would be to prime potential prophylactic vaccine candidates to induce sufficient CD8 + T cells and associated memory responses which can have detrimental effects on the establishment of the parasites ( 15 ). Identifying CD8 + T cell epitopes within filarial antigens could be achieved through immunoinformatics predictions and experimental validations or by screening a library of peptides spanning the complete antigen sequence ( 83 ). Recently, our group identified a CD8 + T cell peptide ( 146 KPWENFMRV 154 ) within onchocystatin, as part of a multi-epitope vaccine candidate for onchocerciasis, which demonstrates promising potential based on bioinformatics analysis ( 98 ).…”

Identifying novel candidates and configurations for human helminth vaccines

“…In part, irradiated larval strategies could not be applied to humans on any scale, and there are far greater regulatory hurdles than in the veterinary setting. Nevertheless, hundreds of candidate antigens have been tested in model systems for filariasis [ 15 , 16 ], schistosomiasis [ 17–19 ], soil-transmitted nematodes [ 20 ] and other human helminth parasites [ 21 ], with trials in endemic populations under way for hookworm and schistosomiasis [ 22 ]. But there remain some fundamental obstacles to achieve fully effective vaccines against human helminth parasites.…”