Limits...
Hypertrophy of infected Peyer's patches arises from global, interferon-receptor, and CD69-independent shutdown of lymphocyte egress.

Schulz O, Ugur M, Friedrichsen M, Radulovic K, Niess JH, Jalkanen S, Krueger A, Pabst O - Mucosal Immunol (2013)

Bottom Line: Intriguingly, the exact nature of these changes remains undefined to date.Surprisingly, infection-induced lymphocyte sequestration did not require previously proposed mediators of lymphoid organ shutdown including type I interferon receptor and CD69.In contrast, following T-cell receptor-mediated priming, CD69 was essential to selectively block CD4(+) effector T-cell egress.

View Article: PubMed Central - PubMed

Affiliation: Institute of Immunology, Hannover Medical School, Hannover, Germany.

ABSTRACT
Lymphoid organ hypertrophy is a hallmark of localized infection. During the inflammatory response, massive changes in lymphocyte recirculation and turnover boost lymphoid organ cellularity. Intriguingly, the exact nature of these changes remains undefined to date. Here, we report that hypertrophy of Salmonella-infected Peyer's patches (PPs) ensues from a global "shutdown" of lymphocyte egress, which traps recirculating lymphocytes in PPs. Surprisingly, infection-induced lymphocyte sequestration did not require previously proposed mediators of lymphoid organ shutdown including type I interferon receptor and CD69. In contrast, following T-cell receptor-mediated priming, CD69 was essential to selectively block CD4(+) effector T-cell egress. Our findings segregate two distinct lymphocyte sequestration mechanisms, which differentially rely on intrinsic modulation of lymphocyte egress capacity and inflammation-induced changes in the lymphoid organ environment.

Show MeSH

Related in: MedlinePlus

CD69-dependent and -independent lymphocyte retention mechanisms. (a) Quantitative RT-PCR analysis of sphingosine-1-phosphate receptor 1 (S1PR1) expression in fluorescence-activated cell sorting (FACS)-sorted CD19+CD62L+ cells from non-infected and day 7-infected Peyer's patches (PPs). A total of 13 (d0) and 12 (d7) samples generated in eight independent sorts. For one sample, PPs were pooled from one to two mice. Mean+s.d. of samples. (b) CXCR4 expression on CD19+ cells in PPs of non-infected (ctrl), LPS-treated (LPS), and day 7-infected (d7) mice, determined using flow cytometry. Two independent experiments, total four to six mice per group. Symbols represent PP pools from individual mice. (c) Selective retention of activated CD4+ T cells. CD69wtOTII or CD69−/−OTII cells labeled with cell proliferation dye were transferred to congenic recipients. Fifty microgram OVA were given po, PPs were fluorescein isothiocyanate (FITC)-injected on day 3 and analyzed on day 4. Symbols represent individual PPs. One-way analysis of variance (ANOVA), Tukey post test. FACS plot from CD69wtOTII transfer shows transferred CD4+ cells. Transferred CD4+ cells were subgated on division cycles. Mean+s.d. of individual PPs. Two-way ANOVA, Bonferroni post test comparing genotypes. Four experiments with total 4 (no OVA), 11 (CD69wtOTII+OVA), 8 (CD69−/−OTII+OVA), and three mice per group (LPS). (d) Retention of non-activated OTII cells. OTII cells were transferred to congenic recipients. Mice were infected or not infected and analyzed on days 5–6, 1 day after FITC injection. Left FACS plot is gated on viable PP cells, subsequent plots gated on indicated subpopulations. Two experiments, total four (d0) and six (d5–6) mice. Symbols represent individual PPs. Mann–Whitney test. Fold retention infected/non-infected PPs. Mean+s.d. of experiments.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4060605&req=5

fig8: CD69-dependent and -independent lymphocyte retention mechanisms. (a) Quantitative RT-PCR analysis of sphingosine-1-phosphate receptor 1 (S1PR1) expression in fluorescence-activated cell sorting (FACS)-sorted CD19+CD62L+ cells from non-infected and day 7-infected Peyer's patches (PPs). A total of 13 (d0) and 12 (d7) samples generated in eight independent sorts. For one sample, PPs were pooled from one to two mice. Mean+s.d. of samples. (b) CXCR4 expression on CD19+ cells in PPs of non-infected (ctrl), LPS-treated (LPS), and day 7-infected (d7) mice, determined using flow cytometry. Two independent experiments, total four to six mice per group. Symbols represent PP pools from individual mice. (c) Selective retention of activated CD4+ T cells. CD69wtOTII or CD69−/−OTII cells labeled with cell proliferation dye were transferred to congenic recipients. Fifty microgram OVA were given po, PPs were fluorescein isothiocyanate (FITC)-injected on day 3 and analyzed on day 4. Symbols represent individual PPs. One-way analysis of variance (ANOVA), Tukey post test. FACS plot from CD69wtOTII transfer shows transferred CD4+ cells. Transferred CD4+ cells were subgated on division cycles. Mean+s.d. of individual PPs. Two-way ANOVA, Bonferroni post test comparing genotypes. Four experiments with total 4 (no OVA), 11 (CD69wtOTII+OVA), 8 (CD69−/−OTII+OVA), and three mice per group (LPS). (d) Retention of non-activated OTII cells. OTII cells were transferred to congenic recipients. Mice were infected or not infected and analyzed on days 5–6, 1 day after FITC injection. Left FACS plot is gated on viable PP cells, subsequent plots gated on indicated subpopulations. Two experiments, total four (d0) and six (d5–6) mice. Symbols represent individual PPs. Mann–Whitney test. Fold retention infected/non-infected PPs. Mean+s.d. of experiments.

Mentions: To reconcile our findings with a proposed role for IFNα/β/CD69/S1PR1, we hypothesized that two distinct mechanisms of lymphocyte retention must exist, which differ in their requirement of CD69. CD69 has been suggested to retain lymphocytes during the first hours of lymphocyte activation before other mechanisms, such as transcriptional regulation of S1P receptors, are initiated.24 We therefore measured S1PR1 transcript levels in CD19+CD62L+ cells sorted from PPs. However, we did not observe a consistent reduction in S1PR1 transcript levels in cells from infected PPs compared with cells from non-infected PPs (Figure 8a). Recently, CXCR4 has been reported to promote B-cell egress from PPs.28 We therefore measured CXCR4 surface expression on PP cells from non-treated, LPS-treated, and day 7-infected mice. CXCR4 expression was almost exclusively found on CD19+ cells. However, expression was unaltered in lymphocytes from infected PPs compared with non-infected PPs (Figure 8b). These results suggest that infection does not retain lymphocytes through direct regulation of the lymphocyte egress factors S1PR1 and CXCR4.


Hypertrophy of infected Peyer's patches arises from global, interferon-receptor, and CD69-independent shutdown of lymphocyte egress.

Schulz O, Ugur M, Friedrichsen M, Radulovic K, Niess JH, Jalkanen S, Krueger A, Pabst O - Mucosal Immunol (2013)

CD69-dependent and -independent lymphocyte retention mechanisms. (a) Quantitative RT-PCR analysis of sphingosine-1-phosphate receptor 1 (S1PR1) expression in fluorescence-activated cell sorting (FACS)-sorted CD19+CD62L+ cells from non-infected and day 7-infected Peyer's patches (PPs). A total of 13 (d0) and 12 (d7) samples generated in eight independent sorts. For one sample, PPs were pooled from one to two mice. Mean+s.d. of samples. (b) CXCR4 expression on CD19+ cells in PPs of non-infected (ctrl), LPS-treated (LPS), and day 7-infected (d7) mice, determined using flow cytometry. Two independent experiments, total four to six mice per group. Symbols represent PP pools from individual mice. (c) Selective retention of activated CD4+ T cells. CD69wtOTII or CD69−/−OTII cells labeled with cell proliferation dye were transferred to congenic recipients. Fifty microgram OVA were given po, PPs were fluorescein isothiocyanate (FITC)-injected on day 3 and analyzed on day 4. Symbols represent individual PPs. One-way analysis of variance (ANOVA), Tukey post test. FACS plot from CD69wtOTII transfer shows transferred CD4+ cells. Transferred CD4+ cells were subgated on division cycles. Mean+s.d. of individual PPs. Two-way ANOVA, Bonferroni post test comparing genotypes. Four experiments with total 4 (no OVA), 11 (CD69wtOTII+OVA), 8 (CD69−/−OTII+OVA), and three mice per group (LPS). (d) Retention of non-activated OTII cells. OTII cells were transferred to congenic recipients. Mice were infected or not infected and analyzed on days 5–6, 1 day after FITC injection. Left FACS plot is gated on viable PP cells, subsequent plots gated on indicated subpopulations. Two experiments, total four (d0) and six (d5–6) mice. Symbols represent individual PPs. Mann–Whitney test. Fold retention infected/non-infected PPs. Mean+s.d. of experiments.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4060605&req=5

fig8: CD69-dependent and -independent lymphocyte retention mechanisms. (a) Quantitative RT-PCR analysis of sphingosine-1-phosphate receptor 1 (S1PR1) expression in fluorescence-activated cell sorting (FACS)-sorted CD19+CD62L+ cells from non-infected and day 7-infected Peyer's patches (PPs). A total of 13 (d0) and 12 (d7) samples generated in eight independent sorts. For one sample, PPs were pooled from one to two mice. Mean+s.d. of samples. (b) CXCR4 expression on CD19+ cells in PPs of non-infected (ctrl), LPS-treated (LPS), and day 7-infected (d7) mice, determined using flow cytometry. Two independent experiments, total four to six mice per group. Symbols represent PP pools from individual mice. (c) Selective retention of activated CD4+ T cells. CD69wtOTII or CD69−/−OTII cells labeled with cell proliferation dye were transferred to congenic recipients. Fifty microgram OVA were given po, PPs were fluorescein isothiocyanate (FITC)-injected on day 3 and analyzed on day 4. Symbols represent individual PPs. One-way analysis of variance (ANOVA), Tukey post test. FACS plot from CD69wtOTII transfer shows transferred CD4+ cells. Transferred CD4+ cells were subgated on division cycles. Mean+s.d. of individual PPs. Two-way ANOVA, Bonferroni post test comparing genotypes. Four experiments with total 4 (no OVA), 11 (CD69wtOTII+OVA), 8 (CD69−/−OTII+OVA), and three mice per group (LPS). (d) Retention of non-activated OTII cells. OTII cells were transferred to congenic recipients. Mice were infected or not infected and analyzed on days 5–6, 1 day after FITC injection. Left FACS plot is gated on viable PP cells, subsequent plots gated on indicated subpopulations. Two experiments, total four (d0) and six (d5–6) mice. Symbols represent individual PPs. Mann–Whitney test. Fold retention infected/non-infected PPs. Mean+s.d. of experiments.
Mentions: To reconcile our findings with a proposed role for IFNα/β/CD69/S1PR1, we hypothesized that two distinct mechanisms of lymphocyte retention must exist, which differ in their requirement of CD69. CD69 has been suggested to retain lymphocytes during the first hours of lymphocyte activation before other mechanisms, such as transcriptional regulation of S1P receptors, are initiated.24 We therefore measured S1PR1 transcript levels in CD19+CD62L+ cells sorted from PPs. However, we did not observe a consistent reduction in S1PR1 transcript levels in cells from infected PPs compared with cells from non-infected PPs (Figure 8a). Recently, CXCR4 has been reported to promote B-cell egress from PPs.28 We therefore measured CXCR4 surface expression on PP cells from non-treated, LPS-treated, and day 7-infected mice. CXCR4 expression was almost exclusively found on CD19+ cells. However, expression was unaltered in lymphocytes from infected PPs compared with non-infected PPs (Figure 8b). These results suggest that infection does not retain lymphocytes through direct regulation of the lymphocyte egress factors S1PR1 and CXCR4.

Bottom Line: Intriguingly, the exact nature of these changes remains undefined to date.Surprisingly, infection-induced lymphocyte sequestration did not require previously proposed mediators of lymphoid organ shutdown including type I interferon receptor and CD69.In contrast, following T-cell receptor-mediated priming, CD69 was essential to selectively block CD4(+) effector T-cell egress.

View Article: PubMed Central - PubMed

Affiliation: Institute of Immunology, Hannover Medical School, Hannover, Germany.

ABSTRACT
Lymphoid organ hypertrophy is a hallmark of localized infection. During the inflammatory response, massive changes in lymphocyte recirculation and turnover boost lymphoid organ cellularity. Intriguingly, the exact nature of these changes remains undefined to date. Here, we report that hypertrophy of Salmonella-infected Peyer's patches (PPs) ensues from a global "shutdown" of lymphocyte egress, which traps recirculating lymphocytes in PPs. Surprisingly, infection-induced lymphocyte sequestration did not require previously proposed mediators of lymphoid organ shutdown including type I interferon receptor and CD69. In contrast, following T-cell receptor-mediated priming, CD69 was essential to selectively block CD4(+) effector T-cell egress. Our findings segregate two distinct lymphocyte sequestration mechanisms, which differentially rely on intrinsic modulation of lymphocyte egress capacity and inflammation-induced changes in the lymphoid organ environment.

Show MeSH
Related in: MedlinePlus