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Clonal CD8+ T Cell Persistence and Variable Gene Usage Bias in a Human Transplanted Hand.

Kim JY, Balamurugan A, Azari K, Hofmann C, Ng HL, Reed EF, McDiarmid S, Yang OO - PLoS ONE (2015)

Bottom Line: Profiling of T cell receptor (TCR) variable gene usage and size distribution of the infiltrating cells revealed marked skewing of the TCR repertoire indicating oligoclonality, but relatively normal distributions in the blood.Although sampling limitation prevented complete assessment of the TCR repertoire, sequencing further identified 11 TCR clonal expansions that persisted through varying degrees of clinical rejection and immunosuppressive therapy.These 11 clones were limited to three TCR beta chain variable (BV) gene families.

View Article: PubMed Central - PubMed

Affiliation: Division of Infectious Diseases, Department of Medicine, Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America; Department of Microbiology, Immunology, and Molecular Genetics, Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America.

ABSTRACT
Immune prophylaxis and treatment of transplanted tissue rejection act indiscriminately, risking serious infections and malignancies. Although animal data suggest that cellular immune responses causing rejection may be rather narrow and predictable based on genetic background, there are only limited data regarding the clonal breadth of anti-donor responses in humans after allogeneic organ transplantation. We evaluated the graft-infiltrating CD8+ T lymphocytes in skin punch biopsies of a transplanted hand over 178 days. Profiling of T cell receptor (TCR) variable gene usage and size distribution of the infiltrating cells revealed marked skewing of the TCR repertoire indicating oligoclonality, but relatively normal distributions in the blood. Although sampling limitation prevented complete assessment of the TCR repertoire, sequencing further identified 11 TCR clonal expansions that persisted through varying degrees of clinical rejection and immunosuppressive therapy. These 11 clones were limited to three TCR beta chain variable (BV) gene families. Overall, these data indicate significant oligoclonality and likely restricted BV gene usage of alloreactive CD8+ T lymphocytes, and suggest that changes in rejection status are more due to varying regulation of their activity or number rather than shifts in the clonal populations in the transplanted organ. Given that controlled animal models produce predictable BV usage in T lymphocytes mediating rejection, understanding the determinants of TCR gene usage associated with rejection in humans may have application in specifically targeted immunotherapy.

No MeSH data available.


Related in: MedlinePlus

Spectratype BV peak expansions seen over time in CD8+ T cells from the transplanted hand.Spectratypes for BV families were performed (as in Fig 3) at the indicated time points. A. All expanded peaks (>2 relative units magnitude) are indicated by black shading, according to BV family and peak size. B. The number of observed expansions is plotted against the Banff score at each time point. C. The magnitudes of observed expansions are plotted against the Banff score at each time point. *The results for duplicate sampling on day 751 were combined for panel A, and averaged for panel C.
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pone.0136235.g004: Spectratype BV peak expansions seen over time in CD8+ T cells from the transplanted hand.Spectratypes for BV families were performed (as in Fig 3) at the indicated time points. A. All expanded peaks (>2 relative units magnitude) are indicated by black shading, according to BV family and peak size. B. The number of observed expansions is plotted against the Banff score at each time point. C. The magnitudes of observed expansions are plotted against the Banff score at each time point. *The results for duplicate sampling on day 751 were combined for panel A, and averaged for panel C.

Mentions: Transplanted hand skin biopsies were evaluated longitudinally in this manner between days 573 and 751. There were spectratype peak expansions seen in every tested time point, with a mean of 5.9 (±2.7) expansions per biopsy (Fig 4). Multiple expanded peaks were seen at more than one time point. The most repeated peak expansions were found in families BV07 and BV27, including two peak sizes (#3 and #5) in BV07 that were seen at five of seven time points each, and two peak sizes (#4 and #5) in BV27 that were seen in five and three of seven time points, respectively (Fig 4A). Comparing the numbers (Fig 4B) or magnitudes (Fig 4C) of expansions to the rejection status showed no clear relationship of clonal breadth or magnitude of infiltrating CD8+ T cells. The breadth of expansions was least at days 744 and 751, when there was severe rejection and likely vascular compromise just before resection of the hand, perhaps due to nonspecific influx of circulating lymphocytes. Similar results were seen for AV spectratyping (S2 Fig), although there were more expansions seen, perhaps due to the known incomplete allelic exclusion of AV chains [20] or better sensitivity of the AV PCR primers. Overall, these results suggested likely stability of clones within graft-infiltrating T cells, consistent with other studies in animal organ rejection models using similar spectratyping approaches [21,22].


Clonal CD8+ T Cell Persistence and Variable Gene Usage Bias in a Human Transplanted Hand.

Kim JY, Balamurugan A, Azari K, Hofmann C, Ng HL, Reed EF, McDiarmid S, Yang OO - PLoS ONE (2015)

Spectratype BV peak expansions seen over time in CD8+ T cells from the transplanted hand.Spectratypes for BV families were performed (as in Fig 3) at the indicated time points. A. All expanded peaks (>2 relative units magnitude) are indicated by black shading, according to BV family and peak size. B. The number of observed expansions is plotted against the Banff score at each time point. C. The magnitudes of observed expansions are plotted against the Banff score at each time point. *The results for duplicate sampling on day 751 were combined for panel A, and averaged for panel C.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4546120&req=5

pone.0136235.g004: Spectratype BV peak expansions seen over time in CD8+ T cells from the transplanted hand.Spectratypes for BV families were performed (as in Fig 3) at the indicated time points. A. All expanded peaks (>2 relative units magnitude) are indicated by black shading, according to BV family and peak size. B. The number of observed expansions is plotted against the Banff score at each time point. C. The magnitudes of observed expansions are plotted against the Banff score at each time point. *The results for duplicate sampling on day 751 were combined for panel A, and averaged for panel C.
Mentions: Transplanted hand skin biopsies were evaluated longitudinally in this manner between days 573 and 751. There were spectratype peak expansions seen in every tested time point, with a mean of 5.9 (±2.7) expansions per biopsy (Fig 4). Multiple expanded peaks were seen at more than one time point. The most repeated peak expansions were found in families BV07 and BV27, including two peak sizes (#3 and #5) in BV07 that were seen at five of seven time points each, and two peak sizes (#4 and #5) in BV27 that were seen in five and three of seven time points, respectively (Fig 4A). Comparing the numbers (Fig 4B) or magnitudes (Fig 4C) of expansions to the rejection status showed no clear relationship of clonal breadth or magnitude of infiltrating CD8+ T cells. The breadth of expansions was least at days 744 and 751, when there was severe rejection and likely vascular compromise just before resection of the hand, perhaps due to nonspecific influx of circulating lymphocytes. Similar results were seen for AV spectratyping (S2 Fig), although there were more expansions seen, perhaps due to the known incomplete allelic exclusion of AV chains [20] or better sensitivity of the AV PCR primers. Overall, these results suggested likely stability of clones within graft-infiltrating T cells, consistent with other studies in animal organ rejection models using similar spectratyping approaches [21,22].

Bottom Line: Profiling of T cell receptor (TCR) variable gene usage and size distribution of the infiltrating cells revealed marked skewing of the TCR repertoire indicating oligoclonality, but relatively normal distributions in the blood.Although sampling limitation prevented complete assessment of the TCR repertoire, sequencing further identified 11 TCR clonal expansions that persisted through varying degrees of clinical rejection and immunosuppressive therapy.These 11 clones were limited to three TCR beta chain variable (BV) gene families.

View Article: PubMed Central - PubMed

Affiliation: Division of Infectious Diseases, Department of Medicine, Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America; Department of Microbiology, Immunology, and Molecular Genetics, Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America.

ABSTRACT
Immune prophylaxis and treatment of transplanted tissue rejection act indiscriminately, risking serious infections and malignancies. Although animal data suggest that cellular immune responses causing rejection may be rather narrow and predictable based on genetic background, there are only limited data regarding the clonal breadth of anti-donor responses in humans after allogeneic organ transplantation. We evaluated the graft-infiltrating CD8+ T lymphocytes in skin punch biopsies of a transplanted hand over 178 days. Profiling of T cell receptor (TCR) variable gene usage and size distribution of the infiltrating cells revealed marked skewing of the TCR repertoire indicating oligoclonality, but relatively normal distributions in the blood. Although sampling limitation prevented complete assessment of the TCR repertoire, sequencing further identified 11 TCR clonal expansions that persisted through varying degrees of clinical rejection and immunosuppressive therapy. These 11 clones were limited to three TCR beta chain variable (BV) gene families. Overall, these data indicate significant oligoclonality and likely restricted BV gene usage of alloreactive CD8+ T lymphocytes, and suggest that changes in rejection status are more due to varying regulation of their activity or number rather than shifts in the clonal populations in the transplanted organ. Given that controlled animal models produce predictable BV usage in T lymphocytes mediating rejection, understanding the determinants of TCR gene usage associated with rejection in humans may have application in specifically targeted immunotherapy.

No MeSH data available.


Related in: MedlinePlus