B cells are the arms factories of the immune system, producing antibodies that target invading microbes for destruction. Generally, B-1 cells have been thought to play a major role in the innate immune response -- the type of immunity that offers rapid, generalized responses to infections. Less understood has been any role in adaptive immunity -- in which the immune system develops a long-term immune response to an invader after vaccination or infection.
The researchers -- Karen Haas, Jonathan Poe, Douglas Steeber and Thomas Tedder -- published their findings in the July 2005 issue of the journal Immunity. The research was sponsored by the National Institutes of Health, the Arthritis Foundation, the Lymphoma Research Foundation and the Leukemia & Lymphoma Society.
The researchers studied a particular type of B cell called the B-1 cell. In contrast to the more conventional B-2 cells, B-1 cells have different distinguishing characteristics such as behavior, anatomical localization and types of antibodies produced. In contrast to well-studied B-2 cells, the cellular origins of B-1 cells and their subtypes remain unknown.
"The true function of B-1 cells in the body has been highly controversial over the past two decades," said Tedder. "They appear to be a primary defense mechanism for innate immunity in infections. In particular, however, the B-1b cells have been largely ignored because they're present in relatively small numbers and are difficult to work with."