When the body is under attack from pathogens, the immune system marshals a diverse collection of immune cells to work together in a tightly orchestrated process and defend the host against the intruders. For many decades, immunologists sorted these cells into ever growing numbers of different types and subtypes mainly based on their morphology and phenotype to understand their function. But novel genomic tools are beginning to reveal new, rare cell types as well as unexpected variability and plasticity within groups upending the traditional view of immune cells assigned to the same category as unvarying entities that behave in a constant manner.

         "Continually evolving genomic tools and single cell analysis technologies are revolutionizing our understanding of the human immune system in health and disease," says Pandurangan Vijayanand, M.D., Ph.D., Associate Professor and William K. Bowes Jr. Distinguished Professor at LJI who led the study. "But this is just the beginning of the genomic journey. By applying these tools in relevant diseases and cell types we are changing our understanding of the biology of human immune cells."