Neutrophils–short-lived, highly mobile and versatile–outnumber all other immune cells circulating through the blood stream. Now, researchers at La Jolla Institute for Allergy and Immunology identified a progenitor of neutrophils in the bone marrow of mice and humans and tied it to cancer-promoting activities.
A team led by LJI researchers reveals that bystander cell accumulation antagonizes rather than abets cell-killing by specific CTLs, curbing inflammation. This is noteworthy because that chief anti-inflammatory role has been traditionally ascribed to what are called regulatory T cells, or “Tregs”, which dampen autoimmune responses. T
La Jolla Institute scientists provide new insights into how so-called CD4 cytotoxic T cells arise in humans and thus could facilitate improved vaccine design.
Helper T cells move toward inflamed tissue using membrane protrusions that stabilize them and provide traction on the vasculature. Using high-resolution microscopy and global molecular analysis, the team shows that immature T cells lack these protrusions but that maturing T-cells switch on a gene expression program to create material to construct them.
The development of an HIV vaccine has proven extraordinarily difficult. One of the reasons is that naive precursor B cells that can give rise to mature B cells producing broadly neutralizing antibodies are exceedingly rare within the average human. Yet, despite their low frequency these B cell precursors can outcompete their B cell competitors under the right conditions.