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Faculty Irving Goldschneider
Professor of Immunology
igoldsch@neuron.uchc.edu
1. Development of T Lymphocytes. Despite information about
maturational events amongst thymocytes, substantial controversy remains
about the origins, function, and fate of recent thymic emigrants (RTE’s)
and prothymocytes. To address these questions, we have described markers
that uniquely define RTE’s and permit their isolation in high degrees of
purity. In addition, we have developed intravenous and intrathymic
adoptive transfer assays and parabiotic animal models in which to
demonstrate the existence of intrathymic microvascular gates, and
intrathymic microenvironmental niches (IMN) for prothymocytes in adult
mice. Our recent work has led us to postulate the existence of a
thymus-bone marrow feedback loop that regulates the generation and
mobilization of prothymocytes in coordination with their periodic
importation by the thymus.
2. Development of B Lymphocytes. We have devised a long-term
lymphoid culture system that selectively supports the generation of
B-lineage precursor cells from rat, mouse, and human bone marrow. We are
using this culture system to identify stage-specific growth factors
(cytokines) responsible for the growth and differentiation of these
cells. Our results have implicated a hybrid cytokine comprised of
Interleukin (IL)-7 and the β-chain of
hepatocyte growth factor (HGFβ) in the
regulation of common lymphoid progenitors and pre-pro-B cell growth and
differentiation. Studies are in progress using IL-7 gene-deleted mice,
to determine the mechanism of action of this novel growth factor. Our
recent results indicated that the IL-7/HGFβ
hybrid cytokine acts by inducing juxtacrine interactions and signaling
through the IL-7 and HGF receptors.
3. The Role of the Thymus in Dominant (Active) Tolerance.
Although the generation of immunoregulatory thymocytes (THYreg) was
first observed more than three decades ago, only indirect evidence had
been provided for their export to the peripheral lymphoid tissues. We
have observed several instances in which RTEs induce systemic tolerance
to autoimmune and autologous graft-versus-host disease and suppress
ongoing immune responses to non-self antigens. Some of these RTEreg have
a abTCR+ CD4+ CD25+ phenotype and
others a TCR+ CD4+ CD8- NK1.1+
phenotype. Our results have demonstrated that the export of RTEreg is a
major mechanism by which the thymus establishes dominant systemic
tolerance throughout life. Our results further suggest that "tolerogenic"
antigen-presenting cells (APCs) induce the formation of (THYreg) by
selectively transporting antigens from the periphery to the thymus.
Publications
Selected Publications:
*Goldschneider, I. (2006) Cyclical mobilization and gated importation
of thymocyte progenitors in the adult mouse. Evidence for a thymus-bone
marrow feedback loop. Immunol. Rev. 209:58-75.
Lai, L., R.A. Zeff, and *Goldschneider, I. (2006) A recombinant
single-chain IL-7/HGFβ
hybrid cytokine induces juxtacrine interactions of the IL-7 and
HGF (c-met) receptors and stimulates the proliferation of CFU-S12,
common lymphoid progenitors (CLP) and pre-pro-B cells. Blood
107:1776-1784.
Donskoy, E. and *Goldschneider, I. (2003) Two developmentally distinct
populations of dendritic cells inhabit the adult mouse thymus.
Demonstration by differential importation of hematogenous precursors
under steady-state conditions. J. Immunol 170:3514-3521.
*Goldschneider, I. and Cone, R. (2003) A central role for peripheral
dendritic cells in the induction of acquired thymic tolerance. Trends
Immunol. 24:77-81.
Donskoy, E. Foss, D. and *Goldschneider, I. (2003) Gated importation of
prothymocytes by adult mouse thymus is coordinated with their periodic
mobilization from bone marrow. J. Immunol. 171:3568-3575.
Wei, C. Lai, L. and *Goldschneider, I. (2002) Pre-pro-B cell
chaingrowth-stimulating factor (PPBSF) upregulates the expression of
the IL-7R and enables pro-B cells to respond to monomeric IL-7. J.
Interferon Cytokine Res. 22:823-832.
Foss, D.L., Donskoy E. and *Goldschneider, I. (2002) Functional
demonstration of intrathymic binding sites and microvascular gates for
prothymocytes in irradiated mice. Int. Immunol. 14:331-338.
Foss, D.L., Donskoy, E. and *Goldschneider, I. (2001) The importation of
hematogenous precursors by the thymus is a gated phenomenon in normal
adult mice. J. Exp. Med. 183:365-373.
Wu, D.Y. and Goldschneider, I. (2001) Tolerance to cyclosporin-A-induced
subset of recentCD25autologous graft-versus-host disease is mediated
by a CD4 thymic emigrants. J. Immunol. 166:7158-7164.
Lai, L. and *Golschneider, I. (2001) Cutting Edge: Identification of a
hybrid -chain of the Heptocyte Growthcytokine consisting of
Interleukin-7 and the Factor/Scatter Factor. J. Immunol. 167:3550-3554.
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