Comparing cytokine production and clinical response following vaccination with BCG Moreau and BCG Russia strains in a Brazilian infant population

Evolution of the Bacillus Calmette-Guérin scar Russia and Moreau strains in newborns: A brazilian cohort

Background

In Brazil, in 1925, the Moreau strain was introduced, and since its implementation, it has been the routine vaccine for health services. Since 2013, many countries, including Brazil, have been experiencing problems with the production of vaccines. As of January 2018, the country started to use the BCG vaccine with Russia strain, developed by the Serum Institute India.

Objective

To describe the evolution of the vaccine scar in neonates vaccinated by BCG-Russia compared to BCG-Moreau.

Methods

This was a cohort study was conducted in Salvador city, northeast Brazil. The study population consisted of newborns from the reference maternity hospital, who were vaccinated with BCG-ID strains Moreau or Russia, followed up to assess vaccine lesion evolution.

Results

It was observed that regardless of the vaccine strains, the evolution of the lesion was the same: wheal, reddish macula, induration, pustule, ulcer, and scar. The proportion of vaccine scar in the group vaccinated with BCG Russia was lower than that of BCG Moreau, 62.5 % and 90.9 %, respectively, with a statistically significant difference.

Conclusion

The evolution of the scar by BCG-Russia was similar to the Moreau scar, however different proportions were observed in different stages of lesion between the groups.

The role of IL-32 in Bacillus Calmette-Guérin (BCG)-induced trained immunity in infections caused by different Leishmania spp

BACKGROUND

Cells of the innate immune system undergo long-term functional reprogramming in response to Bacillus Calmette-Guérin (BCG) exposure via a process called trained immunity, conferring nonspecific protection to unrelated infections. Here, we investigate whether BCG-induced trained immunity is able to protect against infections caused by different Leishmania spp., protozoa that cause cutaneous and mucosal or visceral lesions.

METHODS

We used training models of human monocytes with BCG and subsequent infection by L. braziliensis, L. amazonensis and L. infantum, and the vaccination of wild-type and transgenic mice for IL-32γ before in vivo challenge with parasites.

RESULTS

We demonstrated that monocytes trained with BCG presented enhanced ability to kill L. braziliensis, L. amazonensis and L. infantum through increased production of reactive oxygen species. Interleukin (IL)-32 appears to play an essential role in the development of trained immunity. Indeed, BCG exposure induced IL-32 production in human primary monocytes, both mRNA and protein. We have used a human IL-32γ transgenic mouse model (IL-32γTg) to study the effect of BCG vaccination in different Leishmania infection models. BCG vaccination decreased lesion size and parasite load in infections caused by L. braziliensis and reduced the spread of L. amazonensis to other organs in both infected wild-type (WT) and IL-32γTg mice. In addition, BCG reduced the parasite load in the spleen, liver and bone marrow of both WT and IL-32γTg mice infected with L. infantum. BCG vaccination increased inflammatory infiltrate in infected tissues caused by different Leishmania spp. In all infections, the presence of IL-32γ was not mandatory, but it increased the protective and inflammatory effects of BCG-induced training.

CONCLUSIONS

BCG's ability to train innate immune cells, providing protection against leishmaniasis, as well as the participation of IL-32γ in this process, pave the way for new treatment strategies for this neglected infectious disease.