Vaccines development ofVibrio vulnificus

陳俊良

The Journal of Microbiology, 2005, p.437-442.

Cho-Rok Jung, Min-Jung Park and Moon-Soo Heo

Immunization with Major Outer Membrane Protein of Vibrio vulnificus Elicits Protective Antib

odies in a Murine Model

• The presence of capsular polysaccharides (CPS) demonstrated that an ‘antiphagocytic surface antigen’ helps virulent V. vulnificus strains to resist phagocytosis by human polymorphonuclear leukocyte (PMN)

Kreger et al., 1981

• During colonization, surface materials of the organisms such as CPS, LPS, and outer membrane proteins (OMP) play an important role in the adhesion to host cells

Mirelman, 1986

• Conjugated vaccines between capsular polysaccharide of V. vulnificus (VvPS) - Tetanus toxoid (TT) have been investigated in mouse models

Devi et al., 1996 and Morris Jr et al., 1987

OMP (outer membrane protein)

• OMP of gram-negative bacteria, which form channels for small hydrophilic molecules, are known as porins

• Porins produce water-filled channels across the membrane, such as the OmpF, OmpC, and PhoE of E. coli

• It transports of nutrients, antibiotics and other modulators are performed through these channels

• OMP possess high hydrophobicity, which is one of important forces that macromolecules use to preserve their binding interaction

• OMP can adhere to mucosal membranes and antigen presenting cells of GALT present OMP as antigen to immune cells easily

Motive:

• Richardson et al. (1989) identified specific antigens that are expressed in the outer membrane of whole cells or uniquely by in vivo-grown V. cholerae and which react with immune serum and jejunal fluid

• More than one cell surface protein antigen of V. cholerae was involved in the induction of protective immunity through the inhibition of intestinal colonization of vibrios

• Sciortino (1993) identified 18-kDa cholerae protective antigen which is one of the OMP of V. cholerae

• Sperandio et al. (1995) presented evidence that the OmpU of V. cholerae acts as an adherence factor during the colonization of epithelial cells

whether MOMP was present as an antigen during the bacterial infection process

The rabbit developed serum antibody reacted with MOMP

Coomassie blue staining Western blotting

2, whole bacteria3, soluble protein4, insoluble protein

1, whole bacteria2, soluble protein3, insoluble proteinMOMP, major outer membrane protein

Molecular size of MOMP was identified as 36-kDa on 13% SDS-PAGE

N-terminal sequences of MOMP revealed a high degreesimilarity with OmpU of V. vulnificus CMCP6 and YJ016

Immunization with MOMP produced specific IgG and IgM

IgG IgM

MOMP stimulated humoral immune response

MOMP may have stimulated the complementsystem in cooperation with Alum

protective immunity of MOMP against V. vulnificus infection

BALB/c mice (n = 10) were immunized with 40 μg of MOMP.

infected with V. vulnificus (107) after immunization (IP)

immunized mice were healthy until 28 days after the inoculation

Discussion:

• Most bacterial porins were expected to be strong immunogens that stimulated the host immune system.

• Galdiero et al., reported that porins of Salmonella typhimurium stimulated Th1 and Th2 cells and IL-1 and IL-6 gene expression in mice.

• Gordon and Alistair reported OMP like porins might be a candidate vaccine due to the hydrophobicity and immunogenicity of this molecule.