Limits...
Heterologous immunity triggered by a single, latent virus in Mus musculus: combined costimulation- and adhesion- blockade decrease rejection.

Beus JM, Hashmi SS, Selvaraj SA, Duan D, Stempora LL, Monday SA, Cheeseman JA, Hamby KM, Speck SH, Larsen CP, Kirk AD, Kean LS - PLoS ONE (2013)

Bottom Line: MHV68 infection was correlated with multimodal immune deviation, which included increased secretion of CXCL9 and CXCL10, and with the expansion of a CD8(dim) T cell population.In the setting of MHV68 latency, recipients demonstrated accelerated costimulation blockade-resistant rejection of skin allografts compared to non-infected animals (MST 13.5 d in infected animals vs 22 d in non-infected animals, p<.0001).While in the non-infected cohort, either CTLA-4-Ig or anti-CD154 alone could effectively pair with adhesion blockade to prolong allograft acceptance, in infected animals, the prolonged acceptance of skin grafts could only be recapitulated when anti-LFA-1 and anti-VLA-4 antibodies were combined with anti-CD154 (without CTLA-4-Ig, MST>100 d).

View Article: PubMed Central - PubMed

Affiliation: Emory Transplant Center, Emory University School of Medicine, Atlanta, Georgia, United States of America.

ABSTRACT
The mechanisms underlying latent-virus-mediated heterologous immunity, and subsequent transplant rejection, especially in the setting of T cell costimulation blockade, remain undetermined. To address this, we have utilized MHV68 to develop a rodent model of latent virus-induced heterologous alloimmunity. MHV68 infection was correlated with multimodal immune deviation, which included increased secretion of CXCL9 and CXCL10, and with the expansion of a CD8(dim) T cell population. CD8(dim) T cells exhibited decreased expression of multiple costimulation molecules and increased expression of two adhesion molecules, LFA-1 and VLA-4. In the setting of MHV68 latency, recipients demonstrated accelerated costimulation blockade-resistant rejection of skin allografts compared to non-infected animals (MST 13.5 d in infected animals vs 22 d in non-infected animals, p<.0001). In contrast, the duration of graft acceptance was equivalent between non-infected and infected animals when treated with combined anti-LFA-1/anti-VLA-4 adhesion blockade (MST 24 d for non-infected and 27 d for infected, p = n.s.). The combination of CTLA-4-Ig/anti-CD154-based costimulation blockade+anti-LFA-1/anti-VLA-4-based adhesion blockade led to prolonged graft acceptance in both non-infected and infected cohorts (MST>100 d for both, p<.0001 versus costimulation blockade for either). While in the non-infected cohort, either CTLA-4-Ig or anti-CD154 alone could effectively pair with adhesion blockade to prolong allograft acceptance, in infected animals, the prolonged acceptance of skin grafts could only be recapitulated when anti-LFA-1 and anti-VLA-4 antibodies were combined with anti-CD154 (without CTLA-4-Ig, MST>100 d). Graft acceptance was significantly impaired when CTLA-4-Ig alone (no anti-CD154) was combined with adhesion blockade (MST 41 d). These results suggest that in the setting of MHV68 infection, synergy occurs predominantly between adhesion pathways and CD154-based costimulation, and that combined targeting of both pathways may be required to overcome the increased risk of rejection that occurs in the setting of latent-virus-mediated immune deviation.

Show MeSH

Related in: MedlinePlus

Abbreviated skin allograft survival in MHV68 is not due to MHV68-associated Vβ4+CD8+ expansion.A) Representative flow cytometric plots showing TCR Vβ4 staining versus CD8 staining in mice infected with wild-type MHV68 (left) and the mutant M1.STOP MHV68 (right). B) Kaplan-Meier survival curves comparing skin graft survival for non-infected mice treated with CoB (solid black line, MST 22 d, n = 48, 8 independent experiments) and those infected with the M1.STOP MHV68 mutant virus also treated with CoB (dashed green line, MST 17 d, n = 26 from 3 independent experiments). The log-rank comparison of graft survival between the two groups yielded p<.0001. C) Representative flow cytometric plots showing TCR Vβ4 expression versus CD8 expression in mice infected with wild-type MHV68. The animal in the plot on the left received a non-functional antibody of the same isotype as the antibody used for depletion of Vβ4+ cells (right plot). D) Kaplan-Meier survival curves comparing skin graft survival in non-infected mice treated with CoB (solid black line, MST 22 d, n = 48, 8 independent experiments), MHV68-infected mice treated with a Vβ4-depleting antibody (dashed blue line, MST 14 d, n = 15, 2 independent experiments), and MHV68-infected mice treated with a non-functional antibody (dotted black line, MST 13 d, n = 13, 2 independent experiments) of the same isotype as the Vβ4-depleting antibody. Statistical comparison of the two MHV68-infected cohorts (depleted and isotype control) with the log-rank method yielded a non-significant p-value while comparison of either of the MHV68-infected cohorts with the non-infected cohort yielded p<.0001 despite Vβ4 depletion.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3733932&req=5

pone-0071221-g005: Abbreviated skin allograft survival in MHV68 is not due to MHV68-associated Vβ4+CD8+ expansion.A) Representative flow cytometric plots showing TCR Vβ4 staining versus CD8 staining in mice infected with wild-type MHV68 (left) and the mutant M1.STOP MHV68 (right). B) Kaplan-Meier survival curves comparing skin graft survival for non-infected mice treated with CoB (solid black line, MST 22 d, n = 48, 8 independent experiments) and those infected with the M1.STOP MHV68 mutant virus also treated with CoB (dashed green line, MST 17 d, n = 26 from 3 independent experiments). The log-rank comparison of graft survival between the two groups yielded p<.0001. C) Representative flow cytometric plots showing TCR Vβ4 expression versus CD8 expression in mice infected with wild-type MHV68. The animal in the plot on the left received a non-functional antibody of the same isotype as the antibody used for depletion of Vβ4+ cells (right plot). D) Kaplan-Meier survival curves comparing skin graft survival in non-infected mice treated with CoB (solid black line, MST 22 d, n = 48, 8 independent experiments), MHV68-infected mice treated with a Vβ4-depleting antibody (dashed blue line, MST 14 d, n = 15, 2 independent experiments), and MHV68-infected mice treated with a non-functional antibody (dotted black line, MST 13 d, n = 13, 2 independent experiments) of the same isotype as the Vβ4-depleting antibody. Statistical comparison of the two MHV68-infected cohorts (depleted and isotype control) with the log-rank method yielded a non-significant p-value while comparison of either of the MHV68-infected cohorts with the non-infected cohort yielded p<.0001 despite Vβ4 depletion.

Mentions: Our previous observations in the bone marrow transplant model implicated both viral M1 gene function and Vβ4+CD8+ T cell expansion in the rejection of allogeneic bone marrow during MHV68 latency [3]. However, as shown in Figure 5, in this skin allograft model, using both an M1-deficient MHV68 mutant virus [18] and antibody-mediated depletion of Vβ4+CD8+ T cells, we observed that M1 gene function is dispensable for MHV68-mediated rejection. Thus, as shown in Figures 5A and 5B, mice infected with the MHV68 M1.STOP mutant virus (which lacks both M1 function and M1-dependent Vβ4+CD8+ T cell expansion) exhibited CoBRR (MST = 17 d, n = 26) relative to non-infected mice (MST = 22 d, p<.0001). We further confirmed that Vβ4+CD8+ T cells were not causative of CoBRR in the skin graft model by antibody-mediated depletion of Vβ4+ cells [44] from infected animals. While Vβ4+ T cells are exceedingly difficult to deplete after virus-mediated expansion [18], we found that Vβ4+ T cells could be effectively depleted when antibody treatment was begun before and continued after MHV68 infection. Depletion was confirmed by the absence of staining for both Vβ4+ (Figure 5C) and the isotype of the antibody (not shown). In agreement with the experiments utilizing the M1.STOP virus, infected mice depleted of Vβ4+ cells still experienced significantly accelerated skin allograft rejection (Figure 5D, MST = 14 d, n = 15) relative to non-infected mice (MST = 22 d, p<.0001). Thus, while bulk Vβ4+CD8+ expansion may be sufficient to drive rejection of bone marrow [3], these cells do not appear to mediate skin allograft rejection. As such, the skin graft model described herein may be able to better model the clinical impact of latent viral infection in patients, in which expansion of a similar TCR-β-chain-restricted T cell subset is not generally observed [45], [46].


Heterologous immunity triggered by a single, latent virus in Mus musculus: combined costimulation- and adhesion- blockade decrease rejection.

Beus JM, Hashmi SS, Selvaraj SA, Duan D, Stempora LL, Monday SA, Cheeseman JA, Hamby KM, Speck SH, Larsen CP, Kirk AD, Kean LS - PLoS ONE (2013)

Abbreviated skin allograft survival in MHV68 is not due to MHV68-associated Vβ4+CD8+ expansion.A) Representative flow cytometric plots showing TCR Vβ4 staining versus CD8 staining in mice infected with wild-type MHV68 (left) and the mutant M1.STOP MHV68 (right). B) Kaplan-Meier survival curves comparing skin graft survival for non-infected mice treated with CoB (solid black line, MST 22 d, n = 48, 8 independent experiments) and those infected with the M1.STOP MHV68 mutant virus also treated with CoB (dashed green line, MST 17 d, n = 26 from 3 independent experiments). The log-rank comparison of graft survival between the two groups yielded p<.0001. C) Representative flow cytometric plots showing TCR Vβ4 expression versus CD8 expression in mice infected with wild-type MHV68. The animal in the plot on the left received a non-functional antibody of the same isotype as the antibody used for depletion of Vβ4+ cells (right plot). D) Kaplan-Meier survival curves comparing skin graft survival in non-infected mice treated with CoB (solid black line, MST 22 d, n = 48, 8 independent experiments), MHV68-infected mice treated with a Vβ4-depleting antibody (dashed blue line, MST 14 d, n = 15, 2 independent experiments), and MHV68-infected mice treated with a non-functional antibody (dotted black line, MST 13 d, n = 13, 2 independent experiments) of the same isotype as the Vβ4-depleting antibody. Statistical comparison of the two MHV68-infected cohorts (depleted and isotype control) with the log-rank method yielded a non-significant p-value while comparison of either of the MHV68-infected cohorts with the non-infected cohort yielded p<.0001 despite Vβ4 depletion.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3733932&req=5

pone-0071221-g005: Abbreviated skin allograft survival in MHV68 is not due to MHV68-associated Vβ4+CD8+ expansion.A) Representative flow cytometric plots showing TCR Vβ4 staining versus CD8 staining in mice infected with wild-type MHV68 (left) and the mutant M1.STOP MHV68 (right). B) Kaplan-Meier survival curves comparing skin graft survival for non-infected mice treated with CoB (solid black line, MST 22 d, n = 48, 8 independent experiments) and those infected with the M1.STOP MHV68 mutant virus also treated with CoB (dashed green line, MST 17 d, n = 26 from 3 independent experiments). The log-rank comparison of graft survival between the two groups yielded p<.0001. C) Representative flow cytometric plots showing TCR Vβ4 expression versus CD8 expression in mice infected with wild-type MHV68. The animal in the plot on the left received a non-functional antibody of the same isotype as the antibody used for depletion of Vβ4+ cells (right plot). D) Kaplan-Meier survival curves comparing skin graft survival in non-infected mice treated with CoB (solid black line, MST 22 d, n = 48, 8 independent experiments), MHV68-infected mice treated with a Vβ4-depleting antibody (dashed blue line, MST 14 d, n = 15, 2 independent experiments), and MHV68-infected mice treated with a non-functional antibody (dotted black line, MST 13 d, n = 13, 2 independent experiments) of the same isotype as the Vβ4-depleting antibody. Statistical comparison of the two MHV68-infected cohorts (depleted and isotype control) with the log-rank method yielded a non-significant p-value while comparison of either of the MHV68-infected cohorts with the non-infected cohort yielded p<.0001 despite Vβ4 depletion.
Mentions: Our previous observations in the bone marrow transplant model implicated both viral M1 gene function and Vβ4+CD8+ T cell expansion in the rejection of allogeneic bone marrow during MHV68 latency [3]. However, as shown in Figure 5, in this skin allograft model, using both an M1-deficient MHV68 mutant virus [18] and antibody-mediated depletion of Vβ4+CD8+ T cells, we observed that M1 gene function is dispensable for MHV68-mediated rejection. Thus, as shown in Figures 5A and 5B, mice infected with the MHV68 M1.STOP mutant virus (which lacks both M1 function and M1-dependent Vβ4+CD8+ T cell expansion) exhibited CoBRR (MST = 17 d, n = 26) relative to non-infected mice (MST = 22 d, p<.0001). We further confirmed that Vβ4+CD8+ T cells were not causative of CoBRR in the skin graft model by antibody-mediated depletion of Vβ4+ cells [44] from infected animals. While Vβ4+ T cells are exceedingly difficult to deplete after virus-mediated expansion [18], we found that Vβ4+ T cells could be effectively depleted when antibody treatment was begun before and continued after MHV68 infection. Depletion was confirmed by the absence of staining for both Vβ4+ (Figure 5C) and the isotype of the antibody (not shown). In agreement with the experiments utilizing the M1.STOP virus, infected mice depleted of Vβ4+ cells still experienced significantly accelerated skin allograft rejection (Figure 5D, MST = 14 d, n = 15) relative to non-infected mice (MST = 22 d, p<.0001). Thus, while bulk Vβ4+CD8+ expansion may be sufficient to drive rejection of bone marrow [3], these cells do not appear to mediate skin allograft rejection. As such, the skin graft model described herein may be able to better model the clinical impact of latent viral infection in patients, in which expansion of a similar TCR-β-chain-restricted T cell subset is not generally observed [45], [46].

Bottom Line: MHV68 infection was correlated with multimodal immune deviation, which included increased secretion of CXCL9 and CXCL10, and with the expansion of a CD8(dim) T cell population.In the setting of MHV68 latency, recipients demonstrated accelerated costimulation blockade-resistant rejection of skin allografts compared to non-infected animals (MST 13.5 d in infected animals vs 22 d in non-infected animals, p<.0001).While in the non-infected cohort, either CTLA-4-Ig or anti-CD154 alone could effectively pair with adhesion blockade to prolong allograft acceptance, in infected animals, the prolonged acceptance of skin grafts could only be recapitulated when anti-LFA-1 and anti-VLA-4 antibodies were combined with anti-CD154 (without CTLA-4-Ig, MST>100 d).

View Article: PubMed Central - PubMed

Affiliation: Emory Transplant Center, Emory University School of Medicine, Atlanta, Georgia, United States of America.

ABSTRACT
The mechanisms underlying latent-virus-mediated heterologous immunity, and subsequent transplant rejection, especially in the setting of T cell costimulation blockade, remain undetermined. To address this, we have utilized MHV68 to develop a rodent model of latent virus-induced heterologous alloimmunity. MHV68 infection was correlated with multimodal immune deviation, which included increased secretion of CXCL9 and CXCL10, and with the expansion of a CD8(dim) T cell population. CD8(dim) T cells exhibited decreased expression of multiple costimulation molecules and increased expression of two adhesion molecules, LFA-1 and VLA-4. In the setting of MHV68 latency, recipients demonstrated accelerated costimulation blockade-resistant rejection of skin allografts compared to non-infected animals (MST 13.5 d in infected animals vs 22 d in non-infected animals, p<.0001). In contrast, the duration of graft acceptance was equivalent between non-infected and infected animals when treated with combined anti-LFA-1/anti-VLA-4 adhesion blockade (MST 24 d for non-infected and 27 d for infected, p = n.s.). The combination of CTLA-4-Ig/anti-CD154-based costimulation blockade+anti-LFA-1/anti-VLA-4-based adhesion blockade led to prolonged graft acceptance in both non-infected and infected cohorts (MST>100 d for both, p<.0001 versus costimulation blockade for either). While in the non-infected cohort, either CTLA-4-Ig or anti-CD154 alone could effectively pair with adhesion blockade to prolong allograft acceptance, in infected animals, the prolonged acceptance of skin grafts could only be recapitulated when anti-LFA-1 and anti-VLA-4 antibodies were combined with anti-CD154 (without CTLA-4-Ig, MST>100 d). Graft acceptance was significantly impaired when CTLA-4-Ig alone (no anti-CD154) was combined with adhesion blockade (MST 41 d). These results suggest that in the setting of MHV68 infection, synergy occurs predominantly between adhesion pathways and CD154-based costimulation, and that combined targeting of both pathways may be required to overcome the increased risk of rejection that occurs in the setting of latent-virus-mediated immune deviation.

Show MeSH
Related in: MedlinePlus