Biology subjects

Harikumar Parvathy, G.

Publications and source records attributed to Harikumar Parvathy, G..

2 recordsLinked to original sources

bioRxiv2026

Hypothermic and Normothermic Machine Perfusion Differentially Shape the Renal Cellular Landscape

The shortage of donor organs has led to an increased use of extended-criteria donors and donation after circulatory death for kidney transplantation, both of which are associated with graft injury. Although machine perfusion (MP) offers a preservation strategy, the most beneficial approach for kidneys with respect to effective graft preservation remains unclear. We compared oxygenated hypothermic (HMP) and normothermic machine perfusion (NMP) using a murine kidney perfusion model regarding intra-graft immune cell composition, viability, and inflammatory responses. NMP resulted in more severe tubular injury, accompanied by increased immune cell mobilization out of the graft. NMP increased early apoptosis among kidney-resident immune-cell populations, whereas endothelial cells showed increased late apoptosis after both strategies. Proximal tubular-cell apoptosis remained comparable to naive tissue, and neither modality reduced reactive oxygen species levels. Both protocols induced antioxidant and hypoxia-responsive genes compared with static cold storage, while NMP elicited a stronger inflammatory response. Treatment with the senolytic ABT-263 demonstrated the models feasibility for investigating renal injury, cellular viability, and immune activation during MP.

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↗