The lymphocyte chemoattractant factor.
The LCF is a unique interleukin without significant homology to other interleukins or chemokines. It is a chemoattractant factor for all CD4+ cells and either uses CD4 as its receptor or utilizes a cell surface complex of molecules for which there is an absolute requirement for the presence of CD4. In addition to its chemoattractant activity, it is a growth factor for CD4+ T cells, inducing resting cells to enter G1, as evidenced by the expression of MHC II molecules and IL-2R. Once induced by LCF to express IL-2R, CD4+ T cells become competent to respond to LCF and progress through the cell cycle to proliferation. LCF's activity on CD4 cells defines a role for CD4 on the eosinophil and monocyte and broadens the scope of functions of CD4 on the T cell. In this regard it may have importance in human disease states that are characterized by increased numbers of activated CD4+ cells, such as sarcoidosis, rheumatoid arthritis, or asthma. Likewise, it may play a key role in monocyte and eosinophil chemotaxis into tissues, being important in the latter in concert with hematopoietic factors that increase the available eosinophil pool.
Center
D M
DM
Pulmonary Center, Boston University School of Medicine, MA 02118-2394.
Berman
J S
JS
Kornfeld
H
H
Theodore
A C
AC
Cruikshank
W W
WW
D015704:CD4 Antigens / Q000502:physiology; D002630:Chemotactic Factors; D003001:Cloning, Molecular; D006801:Humans; D007249:Inflammation; D019410:Interleukin-16; D008222:Lymphokines / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D013601:T-Lymphocytes / Q000502:physiology
D015704:CD4 Antigens; D002630:Chemotactic Factors; D019410:Interleukin-16; D008222:Lymphokines