TY - JOUR
T1 - Both the pre-BCR and the IL-7R alpha are essential for expansion at the pre-BII cell stage in vivo
AU - Erlandsson, L
AU - Licence, S
AU - Gaspal, Fabrina
AU - Lane, Peter
AU - Corcoran, AE
AU - Martensson, IL
PY - 2005/6/1
Y1 - 2005/6/1
N2 - During B cell development, proliferative expansion takes place after expression of the pre-BCR. At this pre-BII cell stage, the IL-7R alpha is also expressed. Some in vitro studies suggest that pre-BCR-dependent expansion relies on the IL-7R alpha, and others that it does not. It has also been suggested that the pre-BCR mediates down-regulation of the IL-7R alpha. However, the in vivo relationship between the pre-BCR and the IL-7R alpha has not been previously examined. Here, we have investigated this by establishing mice lacking both receptors. Our results show that in the absence of the IL-7R alpha, the pre-BII population is reduced, as previously seen in mice lacking the pre-BCR, demonstrating that the IL-7R alpha is important at this stage. A deficiency in both receptors results in a further reduction of the pre-BII cell population. We conclude that both the IL-7Ra and the pre-BCR are required for optimal pre-BII cell expansion. Furthermore, IL-7R alpha expression levels are normal in pre-BCR-deficient mice, suggesting that the pre-BCR does not mediate its down-regulation. As a consequence of the absence of both receptors, the peripheral B cell pool is severely depleted, resulting in atypical splenic B cell structures and reduced serum Ig levels.
AB - During B cell development, proliferative expansion takes place after expression of the pre-BCR. At this pre-BII cell stage, the IL-7R alpha is also expressed. Some in vitro studies suggest that pre-BCR-dependent expansion relies on the IL-7R alpha, and others that it does not. It has also been suggested that the pre-BCR mediates down-regulation of the IL-7R alpha. However, the in vivo relationship between the pre-BCR and the IL-7R alpha has not been previously examined. Here, we have investigated this by establishing mice lacking both receptors. Our results show that in the absence of the IL-7R alpha, the pre-BII population is reduced, as previously seen in mice lacking the pre-BCR, demonstrating that the IL-7R alpha is important at this stage. A deficiency in both receptors results in a further reduction of the pre-BII cell population. We conclude that both the IL-7Ra and the pre-BCR are required for optimal pre-BII cell expansion. Furthermore, IL-7R alpha expression levels are normal in pre-BCR-deficient mice, suggesting that the pre-BCR does not mediate its down-regulation. As a consequence of the absence of both receptors, the peripheral B cell pool is severely depleted, resulting in atypical splenic B cell structures and reduced serum Ig levels.
KW - surrogate light chain
KW - B cell development
KW - pre-BCR
KW - pre-B cell proliferation
KW - IL-7R
U2 - 10.1002/eji.200425821
DO - 10.1002/eji.200425821
M3 - Article
C2 - 15909309
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
SN - 1521-4141
VL - 35
SP - 1969
EP - 1976
JO - European Journal of Immunology
JF - European Journal of Immunology
IS - 6
ER -