More than two billion people are latently infected with Mycobacterium tuberculosis. Most tuberculosis (TB)-subunit vaccines currently in various stages of clinical trials are designed for prevention of active TB, but not to prevent reactivation of latent TB-infection. Thus, there is an urgent need for an effective multi-stage vaccine based on early-expressed and latently-expressed antigens that prevents both acute and latent infections. Areas covered: Here, we reviewed the published pre-clinical and clinical studies of multi-stage subunit vaccines against TB, and the protective capacities of the vaccines were compared with BCG, either alone or in combination with different vaccine delivery systems/adjuvants. The results revealed that multi-stage subunit vaccines induced a wide variety of immune-responses to all forms of TB, including CD8 + T-cell-mediated cytolytic and IFN-γ responses comparable to those induced by the BCG. They could potentially be used as a booster vaccine to improve the efficacy of the BCG. Expert commentary: Multi-stage TB-vaccines could boost BCG-primed immunity, decrease bacterial loads and provide efficient protection against progressive TB-infection, especially in the latent phase. These types of vaccines administered before and after TB-infection can act as pre-exposure, post-exposure and even therapeutic vaccines. In the near future, these vaccines could provide a new generation of prime-vaccines or BCG prime-boosters.
Elevated plasma low-density lipoprotein-cholesterol (LDL-C) concentration is the most important risk factor for atherosclerotic cardiovascular diseases (CVDs). Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a ubiquitously expressed serine proteinase which plays a key role in cholesterol metabolism, but has been found to be implicated in some other lipid-independent physiological processes. In this review, the role of PCSK9 was evaluated not only concerning lipid metabolism but also hepatitis C virus (HCV) infection, bacterial infections/sepsis, and septic shock. Collected data from clinical trials revealed that treatment with PCSK9 inhibitors has beneficial effects in lowering LDL-C via inhibition of LDL-receptors (LDL-R), an antiviral effect on HCV infection via down-regulating the surface expression of LDL-R and CD81 on hepatic cells, and a positive association with increased inflammatory responses, as well as with septic shock by down-regulation of hepatocyte LDL-R. On the other hand, PCSK9 inhibition by therapeutic fully humanized antibodies has positive effects in reducing elevated LDL-C. However, their safety and tolerability is an important issue which has to be taken into consideration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.