Table 2.

Use of GNP based nanovaccine against bacterial pathogens.

SN	Antigen Conjugated with AuNP	GNP/Adjuvant	Immunization Mechanism	Immune Response	Ref.
1	Listeriolysin O peptide (LLO91-99) from Listeria monocytogenes	Conjugated with AuNP	A single intravenous or intraperitoneal immunization of mice	Increase in the number of splenic CD4+ and CD8+ T cells, NK cells, and CD8α+ dendritic cells specific T cell response. An increase in the synthesis of the cytokines IL-12, TNF-α, IFN-γ, and MCP-1. Newborn mice born to vaccinated females were healthy and bacteria-free.	[95,119]
2	A synthetic tetrasaccharide epitope, similar to the capsular polysaccharide of Streptococcus pneumoniae type14	Conjugated with 2 nm AuNP + T helper peptide	Animal: Mice Dose: 3 μg Mode: Intradermal No. of doses: 1	Specific high-titer IgG. Increase in the level of the cytokines IL-2, IL-4, IL-5, IL-17, and IFN-γ. Increased phagocytosis of type 14 bacteria stimulated by antisaccharide antibodies.	[25,120]
3	Bacterial vesicles of the outer membrane of Escherichia coli	Conjugated with 30 nm AuNPs	Injected in mice three times subcutaneously	Rapid maturation and activation of dendritic cells in the lymph nodes. Increase in higher avidity antibodies. Enhancement of IFN-γ and IL-17, indicating strong Th1 and Th17 cellular responses.	[19]
4	Tetanus toxoid Clostridium tetani	Conjugated with 25 nm AuNPs + plant adjuvants (saponins) from Quillaja saponaria (79) and Asparagus racemosus (80)	Subcutaneous injection, or transmucosal delivery	Oral administration highly enhanced mucosal immune response in the presence of plant adjuvants.	[121,122,123]
5	Burkholderia mallei recombinant protein: Hc fragment of tetanus toxin, hemolysin (produced by both B. mallei and B. pseudomallei), and flagellin (produced by B. pseudomallei)	15 nm AuNP functionalized with purified LPS from a nonvirulent B. thailandensis strain	BALB/C mice, intranasal, 3 different dose concentrations	Generated significantly higher antibody titers compared with LPS alone. Improved protection against a lethal inhalation challenge of B. mallei in the murine model of infection.	[26]
6	7.5 μg of tuberculin (mixture of the surface antigens of various types of mycobacteria)	Conjugated with 15 nm AuNPs	Rabbits, four times intramuscularly	High antibody production against multiple types of mycobacteria.	[29,30]
7	Specific immunogenic antigens LomW and EscC from enterohemorrhagic strain E. coli O157: H7	Conjugated with AuNP	Mice, three times subcutaneously, 2-week intervals	Higher-titer IgG and IgA. Serum IgG titer increase correlates with the decrease in the intestinal colonization of E. coli. Reduced the adhesion of E. coli O157: H7 and two different E. coli pathotypes to humans. Bactericidal properties of intestinal epithelial cells specific to antigen generated.	[20]