The pneumococcus is the classic Gram-positive extracellular pathogen. The medical burden
of diseases it causes is amongst the greatest in the world. Intense study for more than 100 …

Natural Abs, belonging to isotypes IgM, IgG3, and IgA, were discovered nearly half a century
ago. Despite knowledge about the role of the polyreactive natural IgM in pathogen …

The existence of IgM has been known for more than a century, but its importance in immunity
and autoimmunity continues to emerge. Studies of mice deficient in secreted IgM have …

B1 cells differ in many ways from conventional B cells, most prominently in the production of
natural immunoglobulin, which is vitally important for protection against pathogens. B1 cells …

The traditional definition of natural antibodies (NAbs) states that these antibodies are
present prior to the body encountering cognate antigen, providing a first line of defense …

The rate of pathogen elimination determines the extent and consequences of an infection. In
this context, the spleen with its highly specialized lymphoid compartments plays a central …

The Streptococcus pneumoniae capsule is vital for virulence and may inhibit complement
activity and phagocytosis. However, there are only limited data on the mechanisms by which …

Natural antibodies are often dismissed from immunological analysis as “background,” but
they may play an important role in conferring immunity against infections. In antibody-free …

Whether B-1a (CD5+) cells are a distinct lineage derived from committed fetal/neonatal
precursors or arise from follicular B-2 cells in response to BCR ligation and other, unknown …

Summary B-1a and B-1b lymphocytes were found to exhibit specialized roles in providing
immunity to Streptococcus pneumoniae and differ dramatically in their developmental …