Plasmodium falciparum malaria causes 500 million clinical cases with approximately one million deaths each year. After many years of exposure, individuals living in endemic areas develop a form of clinical immunity to disease known as premunition, which is characterised by low parasite burdens rather than sterilising immunity. The reason why malaria parasites persist under a state of premunitio...

Natural infection and then recovery are considered to be the most effective means for hosts to build protective immunity. Thus, mimicking natural infection of pathogens, many live attenuated vaccines such as influenza virus, and yellow fever vaccine 17D were developed and have been successfully used to induce protective immunity. However, humans fail to generate long-term protective immunity to...

Chlamydia muridarum and Chlamydia trachomatis mouse models of genital infection have been used to study chlamydial immunity and vaccine development. To assess the protective role of CD4(+) T cells in resolving C. trachomatis and C. muridarum genital tract infections, we used the female mouse model and evaluated infection in the presence and absence of CD4(+) T cells. In contrast to C. muridarum...

Smallpox has been eradicated but stockpiles of the causative infectious agent, variola virus, have been maintained over decades. Today, the threat of accidental or intentional poxvirus release is accompanied by the fact that the existing licensed smallpox vaccines cause rare but severe adverse reactions yet are the only products with approved efficacy against smallpox. New safer vaccines and ne...

The balance between regulatory and inflammatory immune responses is critical to maintain intestinal homeostasis. Furthermore, the nature of the inflammatory response needs to be tailored to the tissue to provide proper protective immunity while preserving host integrity. TLR2 (Toll-like receptor 2) is a unique TLR in that it has been shown to promote regulatory and inflammatory T cell responses...

The herpes simplex virus 2 dl5-29 replication-defective mutant virus has been shown to induce protective immunity in mice and both prophylactic and therapeutic immunity in guinea pigs. In an attempt to improve the efficacy of dl5-29 we disrupted its U(L)41 gene, producing the triple mutant virus dl5-29-41L. dl5-29-41L has a decreased ability to inhibit host cell protein synthesis and a reduced ...

Merozoite surface protein 1 (MSP1) has been identified as a target antigen for protective immune responses against asexual blood stage malaria, but effective vaccines based on MSP1 have not been developed so far. We have modified the sequence of Plasmodium yoelii MSP119 (the C-terminal region of the molecule) and examined the ability of the variant proteins to bind protective monoclonal antibod...