Plasmid DNA vaccination using skin electroporation promotes poly-functional CD4 T-cell responses

Area of Science:

• Immunology
• Vaccinology
• Molecular Biology

Background:

• Plasmid DNA vaccination with skin electroporation (EP) is a minimally invasive method for robust humoral and CD8(+) T-cell responses.
• Limited data exists on CD4(+) T-cell immunity induction via skin EP.
• CD4(+) T-cell help is vital for effective immune defense against pathogens.

Purpose of the Study:

• To compare the efficacy of homologous prime/boost DNA vaccinations delivered by skin EP versus intramuscular (i.m.) injection.
• To investigate the induction and complexity of CD4(+) T-cell responses to the human immunodeficiency virus (HIV) Gag antigen.
• To assess the potential of skin EP for generating poly-functional CD4(+) T-cell help.

Main Methods:

• Homologous prime/boost DNA vaccination strategies were employed.
• Delivery methods compared: skin electroporation (EP) and intramuscular (i.m.) injection.
• Immune responses were analyzed using cytokine enzyme-linked immunosorbent spot (ELISPOT) assay and multiparameter flow cytometry for CD4(+) T-cell responses to HIV Gag antigen.

Main Results:

• Both skin EP and i.m. DNA vaccination induced single- and poly-functional vaccine-specific CD4(+) T cells.
• Skin EP, despite a five-fold lower DNA dose, elicited significantly higher magnitudes of multiple-cytokine-producing CD4(+) T cells compared to i.m. injection.
• These findings suggest skin EP may induce superior poly-functional T-cell help.

Conclusions:

• Skin EP is an effective method for inducing CD4(+) T-cell immunity.
• Skin EP demonstrates potential for enhanced poly-functional T-cell help compared to i.m. delivery.
• This approach holds promise for improving vaccine efficacy against infectious agents.