Limits...
Dendritic cells enhance growth and differentiation of CD40-activated B lymphocytes.

Dubois B, Vanbervliet B, Fayette J, Massacrier C, Van Kooten C, Brière F, Banchereau J, Caux C - J. Exp. Med. (1997)

Bottom Line: Furthermore, after CD40 ligation, DC enhanced by 30-300-fold the secretion of IgG and IgA by sIgD- B cells (essentially memory B cells).In the presence of DC, naive sIgD+ B cells produced, in response to interleukin-2, large amounts of IgM.Thus, in addition to activating naive T cells in the extrafollicular areas of secondary lymphoid organs, DC may directly modulate B cell growth and differentiation.

View Article: PubMed Central - PubMed

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

ABSTRACT
After antigen capture, dendritic cells (DC) migrate into T cell-rich areas of secondary lymphoid organs, where they induce T cell activation, that subsequently drives B cell activation. Here, we investigate whether DC, generated in vitro, can directly modulate B cell responses, using CD40L-transfected L cells as surrogate activated T cells. DC, through the production of soluble mediators, stimulated by 3- to 6-fold the proliferation and subsequent recovery of B cells. Furthermore, after CD40 ligation, DC enhanced by 30-300-fold the secretion of IgG and IgA by sIgD- B cells (essentially memory B cells). In the presence of DC, naive sIgD+ B cells produced, in response to interleukin-2, large amounts of IgM. Thus, in addition to activating naive T cells in the extrafollicular areas of secondary lymphoid organs, DC may directly modulate B cell growth and differentiation.

Show MeSH
CD40-activated B cells are in close contact with D–Lc in coculture. 105 highly purified B cells were cultured in 24-well plates over 2.5 ×  104 irradiated CD40L L cells and 5 × 104 D–Lc. After 8 d of coculture, cells were gently harvested, cytocentrifuged, and used for (A) MGG staining, (B)  anti-HLA-DR staining, (C) anti-CD80 (B7-1) staining, and (D) double anti-HLA-DR (red) and anti-CD20 (blue) staining (as detailed in Materials and  Methods). Magnification, ×400 (A, B, C); ×1000 (D).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2196162&req=5

Figure 7: CD40-activated B cells are in close contact with D–Lc in coculture. 105 highly purified B cells were cultured in 24-well plates over 2.5 × 104 irradiated CD40L L cells and 5 × 104 D–Lc. After 8 d of coculture, cells were gently harvested, cytocentrifuged, and used for (A) MGG staining, (B) anti-HLA-DR staining, (C) anti-CD80 (B7-1) staining, and (D) double anti-HLA-DR (red) and anti-CD20 (blue) staining (as detailed in Materials and Methods). Magnification, ×400 (A, B, C); ×1000 (D).

Mentions: As previously described, B lymphocytes proliferate in clusters over CD40L L cells. Addition of D–Lc enhance the size and number of these clusters, which include L cells and D–Lc (data not shown). Giemsa staining on 6-d coculture cytospins shows close contacts between CD40-activated B cells and D–Lc (Fig. 7 A). Immunostainings on such cytospins showed large HLA-DR2+ CD80high cells with dendritic morphology surrounded by HLA-DR2+ CD80low B cells (Fig. 7, B and C). Immunostainings using anti-CD3 mAb failed to detect any positive cells (data not shown). Double stainings definitely identifies CD40-activated B cells (CD20+/HLA-DRlow) in close contacts with D–Lc (CD20−/ HLA-DRhigh), suggesting that these interactions may contribute to the D–Lc-dependent stimulation of B cell growth and differentiation described in this study.


Dendritic cells enhance growth and differentiation of CD40-activated B lymphocytes.

Dubois B, Vanbervliet B, Fayette J, Massacrier C, Van Kooten C, Brière F, Banchereau J, Caux C - J. Exp. Med. (1997)

CD40-activated B cells are in close contact with D–Lc in coculture. 105 highly purified B cells were cultured in 24-well plates over 2.5 ×  104 irradiated CD40L L cells and 5 × 104 D–Lc. After 8 d of coculture, cells were gently harvested, cytocentrifuged, and used for (A) MGG staining, (B)  anti-HLA-DR staining, (C) anti-CD80 (B7-1) staining, and (D) double anti-HLA-DR (red) and anti-CD20 (blue) staining (as detailed in Materials and  Methods). Magnification, ×400 (A, B, C); ×1000 (D).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2196162&req=5

Figure 7: CD40-activated B cells are in close contact with D–Lc in coculture. 105 highly purified B cells were cultured in 24-well plates over 2.5 × 104 irradiated CD40L L cells and 5 × 104 D–Lc. After 8 d of coculture, cells were gently harvested, cytocentrifuged, and used for (A) MGG staining, (B) anti-HLA-DR staining, (C) anti-CD80 (B7-1) staining, and (D) double anti-HLA-DR (red) and anti-CD20 (blue) staining (as detailed in Materials and Methods). Magnification, ×400 (A, B, C); ×1000 (D).
Mentions: As previously described, B lymphocytes proliferate in clusters over CD40L L cells. Addition of D–Lc enhance the size and number of these clusters, which include L cells and D–Lc (data not shown). Giemsa staining on 6-d coculture cytospins shows close contacts between CD40-activated B cells and D–Lc (Fig. 7 A). Immunostainings on such cytospins showed large HLA-DR2+ CD80high cells with dendritic morphology surrounded by HLA-DR2+ CD80low B cells (Fig. 7, B and C). Immunostainings using anti-CD3 mAb failed to detect any positive cells (data not shown). Double stainings definitely identifies CD40-activated B cells (CD20+/HLA-DRlow) in close contacts with D–Lc (CD20−/ HLA-DRhigh), suggesting that these interactions may contribute to the D–Lc-dependent stimulation of B cell growth and differentiation described in this study.

Bottom Line: Furthermore, after CD40 ligation, DC enhanced by 30-300-fold the secretion of IgG and IgA by sIgD- B cells (essentially memory B cells).In the presence of DC, naive sIgD+ B cells produced, in response to interleukin-2, large amounts of IgM.Thus, in addition to activating naive T cells in the extrafollicular areas of secondary lymphoid organs, DC may directly modulate B cell growth and differentiation.

View Article: PubMed Central - PubMed

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

ABSTRACT
After antigen capture, dendritic cells (DC) migrate into T cell-rich areas of secondary lymphoid organs, where they induce T cell activation, that subsequently drives B cell activation. Here, we investigate whether DC, generated in vitro, can directly modulate B cell responses, using CD40L-transfected L cells as surrogate activated T cells. DC, through the production of soluble mediators, stimulated by 3- to 6-fold the proliferation and subsequent recovery of B cells. Furthermore, after CD40 ligation, DC enhanced by 30-300-fold the secretion of IgG and IgA by sIgD- B cells (essentially memory B cells). In the presence of DC, naive sIgD+ B cells produced, in response to interleukin-2, large amounts of IgM. Thus, in addition to activating naive T cells in the extrafollicular areas of secondary lymphoid organs, DC may directly modulate B cell growth and differentiation.

Show MeSH