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CD40 ligation on human cord blood CD34+ hematopoietic progenitors induces their proliferation and differentiation into functional dendritic cells.

Flores-Romo L, Björck P, Duvert V, van Kooten C, Saeland S, Banchereau J - J. Exp. Med. (1997)

Bottom Line: DC generated via the CD40 pathway displayed strong major histocompatibility complex class II DR but lacked detectable CD1a and CD40 expression.These features were shared by a dendritic population identified in situ in tonsillar T cell areas.Taken together, the present data demonstrate that CD40 is functional on CD34HPC and its cross-linking by CD40L+ cells results in the generation of DC that may prime immune reactions during antigen-driven responses to pathogenic invasion, thus providing a link between hematopoiesis, innate, and adaptive immunity.

View Article: PubMed Central - PubMed

Affiliation: Schering-Plough, Laboratory for Immunological Research, Dardilly, France.

ABSTRACT
Human CD34+ multilineage progenitor cells (CD34HPC) from cord blood and bone marrow express CD40, a member of the tumor necrosis factor-receptor family present on various hematopoietic and nonhematopoietic cells. As hyper-IgM patients with mutated CD40 ligand (CD40L) exhibit neutropenia, no B cell memory, and altered T cell functions leading to severe infections, we investigated the potential role of CD40 on CD34HPC development. CD40-activated cord blood CD34HPC were found to proliferate and differentiate independently of granulocyte/macrophage colony-stimulating factor, into a cell population with prominent dendritic cell (DC) attributes including priming of allogeneic naive T cells. DC generated via the CD40 pathway displayed strong major histocompatibility complex class II DR but lacked detectable CD1a and CD40 expression. These features were shared by a dendritic population identified in situ in tonsillar T cell areas. Taken together, the present data demonstrate that CD40 is functional on CD34HPC and its cross-linking by CD40L+ cells results in the generation of DC that may prime immune reactions during antigen-driven responses to pathogenic invasion, thus providing a link between hematopoiesis, innate, and adaptive immunity.

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Related in: MedlinePlus

CD40 triggering of CD34+ progenitors specifically induces  the generation of DC that accumulate with time. (A) Human CD34+  progenitor cells seeded in CD40L (LCD40L cells) or in control cultures  (LCD32 cells) were evaluated for DC generation at different times. (B)  The effect of neutralizing antibodies to CD40, CD40L, and GM–CSF, or  an irrelevant control Ab was also determined at day 14. Results are expressed as percentage DC ± SD evaluated in triplicates. Cultures and  evaluation of DC production were performed as described in Materials  and Methods.
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Figure 3: CD40 triggering of CD34+ progenitors specifically induces the generation of DC that accumulate with time. (A) Human CD34+ progenitor cells seeded in CD40L (LCD40L cells) or in control cultures (LCD32 cells) were evaluated for DC generation at different times. (B) The effect of neutralizing antibodies to CD40, CD40L, and GM–CSF, or an irrelevant control Ab was also determined at day 14. Results are expressed as percentage DC ± SD evaluated in triplicates. Cultures and evaluation of DC production were performed as described in Materials and Methods.

Mentions: Kinetic followup of CD40 stimulated CD34HPC indicated early emergence of DC in cultures with 6% identifiable DC at day 4, 16% at day 8, and a maximum 36% by day 14 (Fig. 3 A). As observed for proliferation, DC generation was specific for CD40 engagement, because antibodies to either CD40 or CD40L efficiently blocked their appearance, whereas isotype-matched control antibodies were ineffective (Fig. 3 B). Of note is the fact that a soluble fusion protein constructed with CD40L and CD8 (sCD40L) was also capable of inducing development of DC. However, the soluble product was less effective than polyvalently immobilized CD40L, especially regarding dendrite development (data not shown). Interestingly, neutralizing anti-GM–CSF antibodies did not affect the CD40L-dependent generation of DC (Fig. 3 B), which contrasts with previous studies in vitro where DC generation was strictly dependent on addition of GM–CSF (1, 28–31).


CD40 ligation on human cord blood CD34+ hematopoietic progenitors induces their proliferation and differentiation into functional dendritic cells.

Flores-Romo L, Björck P, Duvert V, van Kooten C, Saeland S, Banchereau J - J. Exp. Med. (1997)

CD40 triggering of CD34+ progenitors specifically induces  the generation of DC that accumulate with time. (A) Human CD34+  progenitor cells seeded in CD40L (LCD40L cells) or in control cultures  (LCD32 cells) were evaluated for DC generation at different times. (B)  The effect of neutralizing antibodies to CD40, CD40L, and GM–CSF, or  an irrelevant control Ab was also determined at day 14. Results are expressed as percentage DC ± SD evaluated in triplicates. Cultures and  evaluation of DC production were performed as described in Materials  and Methods.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2196112&req=5

Figure 3: CD40 triggering of CD34+ progenitors specifically induces the generation of DC that accumulate with time. (A) Human CD34+ progenitor cells seeded in CD40L (LCD40L cells) or in control cultures (LCD32 cells) were evaluated for DC generation at different times. (B) The effect of neutralizing antibodies to CD40, CD40L, and GM–CSF, or an irrelevant control Ab was also determined at day 14. Results are expressed as percentage DC ± SD evaluated in triplicates. Cultures and evaluation of DC production were performed as described in Materials and Methods.
Mentions: Kinetic followup of CD40 stimulated CD34HPC indicated early emergence of DC in cultures with 6% identifiable DC at day 4, 16% at day 8, and a maximum 36% by day 14 (Fig. 3 A). As observed for proliferation, DC generation was specific for CD40 engagement, because antibodies to either CD40 or CD40L efficiently blocked their appearance, whereas isotype-matched control antibodies were ineffective (Fig. 3 B). Of note is the fact that a soluble fusion protein constructed with CD40L and CD8 (sCD40L) was also capable of inducing development of DC. However, the soluble product was less effective than polyvalently immobilized CD40L, especially regarding dendrite development (data not shown). Interestingly, neutralizing anti-GM–CSF antibodies did not affect the CD40L-dependent generation of DC (Fig. 3 B), which contrasts with previous studies in vitro where DC generation was strictly dependent on addition of GM–CSF (1, 28–31).

Bottom Line: DC generated via the CD40 pathway displayed strong major histocompatibility complex class II DR but lacked detectable CD1a and CD40 expression.These features were shared by a dendritic population identified in situ in tonsillar T cell areas.Taken together, the present data demonstrate that CD40 is functional on CD34HPC and its cross-linking by CD40L+ cells results in the generation of DC that may prime immune reactions during antigen-driven responses to pathogenic invasion, thus providing a link between hematopoiesis, innate, and adaptive immunity.

View Article: PubMed Central - PubMed

Affiliation: Schering-Plough, Laboratory for Immunological Research, Dardilly, France.

ABSTRACT
Human CD34+ multilineage progenitor cells (CD34HPC) from cord blood and bone marrow express CD40, a member of the tumor necrosis factor-receptor family present on various hematopoietic and nonhematopoietic cells. As hyper-IgM patients with mutated CD40 ligand (CD40L) exhibit neutropenia, no B cell memory, and altered T cell functions leading to severe infections, we investigated the potential role of CD40 on CD34HPC development. CD40-activated cord blood CD34HPC were found to proliferate and differentiate independently of granulocyte/macrophage colony-stimulating factor, into a cell population with prominent dendritic cell (DC) attributes including priming of allogeneic naive T cells. DC generated via the CD40 pathway displayed strong major histocompatibility complex class II DR but lacked detectable CD1a and CD40 expression. These features were shared by a dendritic population identified in situ in tonsillar T cell areas. Taken together, the present data demonstrate that CD40 is functional on CD34HPC and its cross-linking by CD40L+ cells results in the generation of DC that may prime immune reactions during antigen-driven responses to pathogenic invasion, thus providing a link between hematopoiesis, innate, and adaptive immunity.

Show MeSH
Related in: MedlinePlus