Biology subjects

von Borstel, L.

Publications and source records attributed to von Borstel, L..

3 recordsLinked to original sources

bioRxiv2024

Turning the tables: Loss of adaptive immunity reverses sex differences in tuberculosis

Sex-based differences in innate immunity may play a crucial role in susceptibility to and progression of tuberculosis (TB), a disease that disproportionately affects men. This study aimed to examine whether early host-pathogen interactions contribute to the heightened vulnerability of males to Mycobacterium tuberculosis (Mtb) infection. Using recombination activating gene knockout (RAG KO) mice, which lack adaptive immunity, we were able to isolate and analyze innate immune responses to Mtb without the influence of T and B cells. Surprisingly, and in stark contrast to wild-type mice that reflect the male bias as observed in humans, female RAG KO mice were more susceptible to Mtb than their male counterparts. Increased lung CFU in females was accompanied by a significant rise in inflammation, indicated by elevated levels of inflammatory cytokines and chemokines, as well as a massive influx of neutrophils into the lungs. In contrast, male mice exhibited higher levels of IFN-{gamma} and CCL5, along with a greater presence of NK cells in their lungs, suggesting that, in the absence of adaptive immunity, males benefit from a more robust NK cell response, potentially offering greater protection by better controlling inflammation and slowing disease progression.

immunology↗

bioRxiv2024

Ablation of B cell-derived IL-10 increases tuberculosis resistance

Due to the historical dogma, that host defense against intracellular pathogens is mediated by cell-mediated immunity, B cells have been considered unimportant in providing protection against Mycobacterium tuberculosis (Mtb) and remained understudied for decades. However, emerging evidence suggests a more complex and multifaceted role for B cells in tuberculosis (TB) immunity. They accumulate at the side of infection in both animal models and human TB patients, suggesting a potential link to protective immunity. Still, the diverse roles of B cells in TB immunity continue to be unraveled. Apart from antibodies, B cells produce a wide range of cytokines, which can influence the local immune response. Here we addressed the relevance of interleukin 10 (IL-10) secreting B cells in long-term control of the Mtb Beijing strain HN878. Our research highlights the previously unknown role of B cell-derived IL-10 as a negative regulator of protective immunity in TB. For the first time, we demonstrate that mice lacking B cell-derived IL-10 show increased resistance to aerosol Mtb infection, as evidenced by a delayed onset of clinical symptoms and prolonged survival. Notably, this effect was significantly more pronounced in males compared to females, and was accompanied by male-specific immune alterations, indicating a previously unknown sex-specific regulatory role of B cell-derived IL-10 during Mtb infection.

immunology↗

bioRxiv2024

Sex differences in vaccine induced immunity and protection against Mycobacterium tuberculosis

Tuberculosis (TB) is a disease that has evolved with humankind for millennia, causing approximately 1.3 million deaths worldwide per annum. Although increased male affliction for TB and other infections were long known from an epidemiological perspective, our mechanistic understanding of the underlying immunological divergences is relatively recent. As such, there is insufficient knowledge regarding the sexually dimorphic immune response to TB vaccines, where no accepted correlates of protection are yet available. In this context, our goal was to explore how individual sex influences the protective effects of TB vaccines. For this purpose, we vaccinated female and male C57BL/6 mice with Bacille Calmette-Guerin (BCG) and two recombinant derivatives, VPM1002 and BCG{Delta}BCG1419c, to analyse their protective efficacy against challenge with Mycobacterium tuberculosis HN878. We found poor efficacy of BCG in males and the ability of next generation vaccine candidates to improve protection specifically in males. To determine the underlying mechanisms for the differences in survival upon vaccination between females and males, as well as, among different vaccine candidates, we analysed the distribution and persistence of the vaccine strains, in addition to vaccine-induced immune responses at various time points in draining lymph nodes and spleen. We identified sex specific differences in CD8 T cell proliferation in response to mycobacterial antigens ex vivo, 90 days post-vaccination, that associates with vaccine mediated protection against HN878. By integrating our multi-parametric datasets into principal component analysis, followed by extraction of high-variance features, we have uncovered an additional significant association of early CD4 T cell responses with late CD8 T cell responses as well as with survival post HN878 infection. In addition, we have also identified specific clusters of responding CD8 T cells in spleen post-vaccination, that are globally deficient in males as compared to females, irrespective of the BCG strain administered.

immunology↗