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A negative feedback loop mediated by the Bcl6-cullin 3 complex limits Tfh cell differentiation.

Mathew R, Mao AP, Chiang AH, Bertozzi-Villa C, Bunker JJ, Scanlon ST, McDonald BD, Constantinides MG, Hollister K, Singer JD, Dent AL, Dinner AR, Bendelac A - J. Exp. Med. (2014)

Bottom Line: Intriguingly, we found that Bcl6 was also highly and transiently expressed during the CD4(+)CD8(+) (double positive [DP]) stage of T cell development, in association with the E3 ligase cullin 3 (Cul3), a novel binding partner of Bcl6 which ubiquitinates histone proteins.Although they maintained an apparently normal phenotype after emigration, they expressed increased amounts of Batf and Bcl6 at basal state and produced explosive and prolonged Tfh responses upon subsequent antigen encounter.Ablation of Cul3 in mature CD4(+) splenocytes also resulted in dramatically exaggerated Tfh responses.

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Affiliation: Committee on Immunology, Department of Pathology, Howard Hughes Medical Institute, and Department of Chemistry, University of Chicago, Chicago, IL 60637Committee on Immunology, Department of Pathology, Howard Hughes Medical Institute, and Department of Chemistry, University of Chicago, Chicago, IL 60637Committee on Immunology, Department of Pathology, Howard Hughes Medical Institute, and Department of Chemistry, University of Chicago, Chicago, IL 60637.

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Exaggerated Tfh responses without alteration of Th1 or Th2 programs. (a and b) 0.5 × 106 CD4+ enriched SP thymocytes from OTII or OTII Cul3cKO donors were injected i.v. into CD45 congenic recipients 24 h before injection of OVA + CFA s.c., OVA + alum i.p., or PBS, as indicated. OTII cells were analyzed at day 7 after immunization in inguinal lymph nodes (CFA; a) or spleen (alum; b). (first row) Expression of CXCR5 and PD1. Numbers above the dot plots are the absolute numbers of OTII cells recovered from the lymph nodes or spleen. Numbers in top right quadrants are the percentage of CXCR5+PD1+ (mean ± SEM). (second row) Expression of Ki67 and CXCR5. (third row) Expression of Tbet and Bcl6. Numbers indicate the percentage (mean ± SEM) of TbethiBcl6hi cells (right box) or TbethiBcl6int cells (left box). Background staining is shown after preincubation with an excess of unconjugated antibodies (cold Tbet+Bcl6). (fourth row) Expression of Gata3 and CXCR5 with quadrant statistics (mean ± SEM). Background staining is shown for fluorochrome-conjugated isotype control. Data are representative of two independent experiments with total n = 6 mice.
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fig4: Exaggerated Tfh responses without alteration of Th1 or Th2 programs. (a and b) 0.5 × 106 CD4+ enriched SP thymocytes from OTII or OTII Cul3cKO donors were injected i.v. into CD45 congenic recipients 24 h before injection of OVA + CFA s.c., OVA + alum i.p., or PBS, as indicated. OTII cells were analyzed at day 7 after immunization in inguinal lymph nodes (CFA; a) or spleen (alum; b). (first row) Expression of CXCR5 and PD1. Numbers above the dot plots are the absolute numbers of OTII cells recovered from the lymph nodes or spleen. Numbers in top right quadrants are the percentage of CXCR5+PD1+ (mean ± SEM). (second row) Expression of Ki67 and CXCR5. (third row) Expression of Tbet and Bcl6. Numbers indicate the percentage (mean ± SEM) of TbethiBcl6hi cells (right box) or TbethiBcl6int cells (left box). Background staining is shown after preincubation with an excess of unconjugated antibodies (cold Tbet+Bcl6). (fourth row) Expression of Gata3 and CXCR5 with quadrant statistics (mean ± SEM). Background staining is shown for fluorochrome-conjugated isotype control. Data are representative of two independent experiments with total n = 6 mice.

Mentions: The exaggerated Tfh response was associated with increased expression of Ki67, suggesting markedly increased proliferation of Cul3cKO Tfh cells (Fig. 4 a, second row). It did not appear to occur at the expenses of other T helper programs because Cul3cKO mice immunized with OVA mixed with alum or with OVA mixed with CFA exhibited the same bias toward Gata3+ Th2 cells or Tbet+ Th1 cells, respectively (Fig. 4, a and b). Altogether, these results indicated that although Cul3cKO CD4+ T cells exhibited baseline increases in Batf and Bcl6 after exiting the thymus, they acquired their exaggerated Tfh cell differentiation after immunization in the periphery.


A negative feedback loop mediated by the Bcl6-cullin 3 complex limits Tfh cell differentiation.

Mathew R, Mao AP, Chiang AH, Bertozzi-Villa C, Bunker JJ, Scanlon ST, McDonald BD, Constantinides MG, Hollister K, Singer JD, Dent AL, Dinner AR, Bendelac A - J. Exp. Med. (2014)

Exaggerated Tfh responses without alteration of Th1 or Th2 programs. (a and b) 0.5 × 106 CD4+ enriched SP thymocytes from OTII or OTII Cul3cKO donors were injected i.v. into CD45 congenic recipients 24 h before injection of OVA + CFA s.c., OVA + alum i.p., or PBS, as indicated. OTII cells were analyzed at day 7 after immunization in inguinal lymph nodes (CFA; a) or spleen (alum; b). (first row) Expression of CXCR5 and PD1. Numbers above the dot plots are the absolute numbers of OTII cells recovered from the lymph nodes or spleen. Numbers in top right quadrants are the percentage of CXCR5+PD1+ (mean ± SEM). (second row) Expression of Ki67 and CXCR5. (third row) Expression of Tbet and Bcl6. Numbers indicate the percentage (mean ± SEM) of TbethiBcl6hi cells (right box) or TbethiBcl6int cells (left box). Background staining is shown after preincubation with an excess of unconjugated antibodies (cold Tbet+Bcl6). (fourth row) Expression of Gata3 and CXCR5 with quadrant statistics (mean ± SEM). Background staining is shown for fluorochrome-conjugated isotype control. Data are representative of two independent experiments with total n = 6 mice.
© Copyright Policy - openaccess
Related In: Results  -  Collection

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fig4: Exaggerated Tfh responses without alteration of Th1 or Th2 programs. (a and b) 0.5 × 106 CD4+ enriched SP thymocytes from OTII or OTII Cul3cKO donors were injected i.v. into CD45 congenic recipients 24 h before injection of OVA + CFA s.c., OVA + alum i.p., or PBS, as indicated. OTII cells were analyzed at day 7 after immunization in inguinal lymph nodes (CFA; a) or spleen (alum; b). (first row) Expression of CXCR5 and PD1. Numbers above the dot plots are the absolute numbers of OTII cells recovered from the lymph nodes or spleen. Numbers in top right quadrants are the percentage of CXCR5+PD1+ (mean ± SEM). (second row) Expression of Ki67 and CXCR5. (third row) Expression of Tbet and Bcl6. Numbers indicate the percentage (mean ± SEM) of TbethiBcl6hi cells (right box) or TbethiBcl6int cells (left box). Background staining is shown after preincubation with an excess of unconjugated antibodies (cold Tbet+Bcl6). (fourth row) Expression of Gata3 and CXCR5 with quadrant statistics (mean ± SEM). Background staining is shown for fluorochrome-conjugated isotype control. Data are representative of two independent experiments with total n = 6 mice.
Mentions: The exaggerated Tfh response was associated with increased expression of Ki67, suggesting markedly increased proliferation of Cul3cKO Tfh cells (Fig. 4 a, second row). It did not appear to occur at the expenses of other T helper programs because Cul3cKO mice immunized with OVA mixed with alum or with OVA mixed with CFA exhibited the same bias toward Gata3+ Th2 cells or Tbet+ Th1 cells, respectively (Fig. 4, a and b). Altogether, these results indicated that although Cul3cKO CD4+ T cells exhibited baseline increases in Batf and Bcl6 after exiting the thymus, they acquired their exaggerated Tfh cell differentiation after immunization in the periphery.

Bottom Line: Intriguingly, we found that Bcl6 was also highly and transiently expressed during the CD4(+)CD8(+) (double positive [DP]) stage of T cell development, in association with the E3 ligase cullin 3 (Cul3), a novel binding partner of Bcl6 which ubiquitinates histone proteins.Although they maintained an apparently normal phenotype after emigration, they expressed increased amounts of Batf and Bcl6 at basal state and produced explosive and prolonged Tfh responses upon subsequent antigen encounter.Ablation of Cul3 in mature CD4(+) splenocytes also resulted in dramatically exaggerated Tfh responses.

View Article: PubMed Central - HTML - PubMed

Affiliation: Committee on Immunology, Department of Pathology, Howard Hughes Medical Institute, and Department of Chemistry, University of Chicago, Chicago, IL 60637Committee on Immunology, Department of Pathology, Howard Hughes Medical Institute, and Department of Chemistry, University of Chicago, Chicago, IL 60637Committee on Immunology, Department of Pathology, Howard Hughes Medical Institute, and Department of Chemistry, University of Chicago, Chicago, IL 60637.

Show MeSH
Related in: MedlinePlus