tissue-resident innate-like B lymphocytes

 

Tissue-resident immune cells in the mouse peritoneal cavity (BALB/c), and antigen(ag)-specific B lymphocytes, including VH11+ B-1 cells binding phosphatidylcholine (PtC) and B-1 cells specific to LPS of Francisella tularensis bacteria.

We are interested in understanding the development and function of tissue-resident lymphocytes, in contrast to circulating blood lymphocytes. We have shown that tissue-resident B lymphocytes, such as innate-like B-1a cells, emerge early during fetal development independently of the LT-HSC and then migrate to take residence in serous cavities (i.e. pleural and peritoneal) where they surround the lung and intestinal mucosa. These tissue-resident B lymphocytes carry unique functions that are not performed by peripheral blood or follicular B lymphocytes.

 

Lineage tracing in vivo. Tracing the fate of immune cells that develop during embryogenesis. Spleen from adult wild-type C57BL/6 mice were processed into single cell suspension and stained with fluorochrome-conjugated monoclonal antibodies in an 18-parameter Hi-D FACS panel.

We propose that the development of HSC-independent lineages early in ontogeny represents an evolutionary strategy that ensures the development of an immune system carrying unique functions that are evolutionarily conserved and distinct from the functions of the adaptive immune system operating in adults. 

Currently, we are studying the origin of murine tissue-resident lymphocytes during fetal hematopoiesis using in vivo lineage tracing models. We are also developing humanized mice to study the development and function of human tissue-resident B lymphocytes using human fetal and adult tissues. 

 

humanized mouse model

 
 
 
 

current projects