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Antigen-pulsed CD8alpha+ dendritic cells generate an immune response after subcutaneous injection without homing to the draining lymph node.

Smith AL, Fazekas de St Groth B - J. Exp. Med. (1999)

Bottom Line: In contrast to CD8alpha- dendritic cells, the CD8alpha+ fraction failed to traffic to the draining lymph node and did not generate responses to intravenous peptide.Such responses may have been initiated via transfer of peptide-major histocompatibility complex complexes to migratory host CD8alpha- dendritic cells after injection.These data suggest that correlation of T helper cell type 1 (Th1) and Th2 priming with injection of CD8alpha+ and CD8alpha- dendritic cells, respectively, may not result from direct T cell activation by lymphoid versus myeloid dendritic cells, but rather from indirect modification of the response to immunogenic CD8alpha- dendritic cells by CD8alpha+ dendritic cells.

View Article: PubMed Central - PubMed

Affiliation: Centenary Institute of Cancer Medicine and Cell Biology, Newtown, New South Wales, Australia, 2042.

ABSTRACT
Two subsets of murine splenic dendritic cells, derived from distinct precursors, can be distinguished by surface expression of CD8alpha homodimers. The functions of the two subsets remain controversial, although it has been suggested that the lymphoid-derived (CD8alpha+) subset induces tolerance, whereas the myeloid-derived (CD8alpha-) subset has been shown to prime naive T cells and to generate memory responses. To study their capacity to prime or tolerize naive CD4(+) T cells in vivo, purified CD8alpha+ or CD8alpha- dendritic cells were injected subcutaneously into normal mice. In contrast to CD8alpha- dendritic cells, the CD8alpha+ fraction failed to traffic to the draining lymph node and did not generate responses to intravenous peptide. However, after in vitro pulsing with peptide, strong in vivo T cell responses to purified CD8alpha+ dendritic cells could be detected. Such responses may have been initiated via transfer of peptide-major histocompatibility complex complexes to migratory host CD8alpha- dendritic cells after injection. These data suggest that correlation of T helper cell type 1 (Th1) and Th2 priming with injection of CD8alpha+ and CD8alpha- dendritic cells, respectively, may not result from direct T cell activation by lymphoid versus myeloid dendritic cells, but rather from indirect modification of the response to immunogenic CD8alpha- dendritic cells by CD8alpha+ dendritic cells.

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Local response of CFSE-labeled T cells to in vitro–pulsed  peptide after subcutaneous inoculation of sorted DCs. The total numbers  of CD11c+ DCs in the inocula were 2.5 × 105 CD8+ (2.5 × 105 CD8+  plus 0.03 × 105 CD8−) and 3.0 × 105 CD8− (no detectable CD8+). (A)  Popliteal LN cells were gated for CD4+PI− cells. The data are presented  as 10% probability plots plus outliers. (B) Dot plots of CFSE versus CD69  or CD44 expression within the CD4+PI−Tgα+ T cell gate (boxed in A).
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Figure 2: Local response of CFSE-labeled T cells to in vitro–pulsed peptide after subcutaneous inoculation of sorted DCs. The total numbers of CD11c+ DCs in the inocula were 2.5 × 105 CD8+ (2.5 × 105 CD8+ plus 0.03 × 105 CD8−) and 3.0 × 105 CD8− (no detectable CD8+). (A) Popliteal LN cells were gated for CD4+PI− cells. The data are presented as 10% probability plots plus outliers. (B) Dot plots of CFSE versus CD69 or CD44 expression within the CD4+PI−Tgα+ T cell gate (boxed in A).

Mentions: Because of difficulties in achieving sufficient DC purity in the experiment described above, CD11c+ DCs obtained by positive bead selection were sorted on the basis of CD8α expression, yielding a CD8α− fraction with <0.01% contaminating CD8α+ cells, and a CD8α+ fraction contaminated with 1.0% CD8α− cells. After peptide pulsing, the cells were injected into the hind footpads of 36-2 mice. Once again, the response to CD8α− cells was marginally higher, as indicated by stimulation of one more T cell division than was seen in the response to CD8α+ cells (Fig. 2 A). As expected, expression of the activation markers CD69 and CD44 was increased before the first cell division (Fig. 2 B), and the pattern of CD69 downregulation was consistent with previous data derived from direct peptide administration to TCR Tg mice (Smith, A.L., and B. Fazekas de St. Groth, manuscript in preparation).


Antigen-pulsed CD8alpha+ dendritic cells generate an immune response after subcutaneous injection without homing to the draining lymph node.

Smith AL, Fazekas de St Groth B - J. Exp. Med. (1999)

Local response of CFSE-labeled T cells to in vitro–pulsed  peptide after subcutaneous inoculation of sorted DCs. The total numbers  of CD11c+ DCs in the inocula were 2.5 × 105 CD8+ (2.5 × 105 CD8+  plus 0.03 × 105 CD8−) and 3.0 × 105 CD8− (no detectable CD8+). (A)  Popliteal LN cells were gated for CD4+PI− cells. The data are presented  as 10% probability plots plus outliers. (B) Dot plots of CFSE versus CD69  or CD44 expression within the CD4+PI−Tgα+ T cell gate (boxed in A).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2192915&req=5

Figure 2: Local response of CFSE-labeled T cells to in vitro–pulsed peptide after subcutaneous inoculation of sorted DCs. The total numbers of CD11c+ DCs in the inocula were 2.5 × 105 CD8+ (2.5 × 105 CD8+ plus 0.03 × 105 CD8−) and 3.0 × 105 CD8− (no detectable CD8+). (A) Popliteal LN cells were gated for CD4+PI− cells. The data are presented as 10% probability plots plus outliers. (B) Dot plots of CFSE versus CD69 or CD44 expression within the CD4+PI−Tgα+ T cell gate (boxed in A).
Mentions: Because of difficulties in achieving sufficient DC purity in the experiment described above, CD11c+ DCs obtained by positive bead selection were sorted on the basis of CD8α expression, yielding a CD8α− fraction with <0.01% contaminating CD8α+ cells, and a CD8α+ fraction contaminated with 1.0% CD8α− cells. After peptide pulsing, the cells were injected into the hind footpads of 36-2 mice. Once again, the response to CD8α− cells was marginally higher, as indicated by stimulation of one more T cell division than was seen in the response to CD8α+ cells (Fig. 2 A). As expected, expression of the activation markers CD69 and CD44 was increased before the first cell division (Fig. 2 B), and the pattern of CD69 downregulation was consistent with previous data derived from direct peptide administration to TCR Tg mice (Smith, A.L., and B. Fazekas de St. Groth, manuscript in preparation).

Bottom Line: In contrast to CD8alpha- dendritic cells, the CD8alpha+ fraction failed to traffic to the draining lymph node and did not generate responses to intravenous peptide.Such responses may have been initiated via transfer of peptide-major histocompatibility complex complexes to migratory host CD8alpha- dendritic cells after injection.These data suggest that correlation of T helper cell type 1 (Th1) and Th2 priming with injection of CD8alpha+ and CD8alpha- dendritic cells, respectively, may not result from direct T cell activation by lymphoid versus myeloid dendritic cells, but rather from indirect modification of the response to immunogenic CD8alpha- dendritic cells by CD8alpha+ dendritic cells.

View Article: PubMed Central - PubMed

Affiliation: Centenary Institute of Cancer Medicine and Cell Biology, Newtown, New South Wales, Australia, 2042.

ABSTRACT
Two subsets of murine splenic dendritic cells, derived from distinct precursors, can be distinguished by surface expression of CD8alpha homodimers. The functions of the two subsets remain controversial, although it has been suggested that the lymphoid-derived (CD8alpha+) subset induces tolerance, whereas the myeloid-derived (CD8alpha-) subset has been shown to prime naive T cells and to generate memory responses. To study their capacity to prime or tolerize naive CD4(+) T cells in vivo, purified CD8alpha+ or CD8alpha- dendritic cells were injected subcutaneously into normal mice. In contrast to CD8alpha- dendritic cells, the CD8alpha+ fraction failed to traffic to the draining lymph node and did not generate responses to intravenous peptide. However, after in vitro pulsing with peptide, strong in vivo T cell responses to purified CD8alpha+ dendritic cells could be detected. Such responses may have been initiated via transfer of peptide-major histocompatibility complex complexes to migratory host CD8alpha- dendritic cells after injection. These data suggest that correlation of T helper cell type 1 (Th1) and Th2 priming with injection of CD8alpha+ and CD8alpha- dendritic cells, respectively, may not result from direct T cell activation by lymphoid versus myeloid dendritic cells, but rather from indirect modification of the response to immunogenic CD8alpha- dendritic cells by CD8alpha+ dendritic cells.

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