The bursa of Fabricius and the thymus are "central lymphoid organs" in the chicken, essential
to the ontogenetic development of adaptive immunity in that species. Surgical removal of …

Approximately 500 mya two types of recombinatorial adaptive immune systems appeared in
vertebrates. Jawed vertebrates generate a diverse repertoire of B and T cell antigen …

Although jawless vertebrates are apparently capable of adaptive immune responses, they
have not been found to possess the recombinatorial antigen receptors shared by all jawed …

A clonally diverse anticipatory repertoire in which each lymphocyte bears a unique antigen
receptor is the central feature of the adaptive immune system that evolved in our vertebrate …

Instead of the immunoglobulin-type antigen receptors of jawed vertebrates, jawless fish have
variable lymphocyte receptors (VLRs), which consist of leucine-rich repeat (LRR) modules. …

An Fcα receptor probe of human origin was used to identify novel members of the Ig gene
superfamily in mice. Paired Ig-like receptors, named PIR-A and PIR-B, are predicted from …

We describe a novel cytoplasmic tyrosine kinase, termed BPK (B cell progenitor kinase), which
is expressed in all stages of the B lineage and in myeloid cells. BPK has classic SH1, SH2…

The fine structure and micropinocytotic capabilities of epithelial cells closely associated with
lymphoid follicles in the chicken bursa of Fabricius, rabbit appendix, and mouse Peyer's …

Mice deficient in the cytokines tumor necrosis factor (TNF) or lymphotoxin (LT) α/β lack
polarized B cell follicles in the spleen. Deficiency in CXC chemokine receptor 5 (CXCR5), a …

The primary immunodeficiency disorders reflect abnormalities in the development and
maturation of cells of the immune system. These defects result in an increased susceptibility to …