Retraction: IL-21 Regulates the Differentiation of a Human γδ T Cell Subset Equipped with B Cell Helper Activity

Abstract Cytomegalovirus (CMV) is a major infectious cause of death and disease after transplantation. We have previously demonstrated that the tissue-associated adaptive Vδ2neg γδ T cells are key effectors responding to CMV and associated with recovery, contrasting with their innatelike circulating counterparts, the Vγ9posVδ2pos T cells that respond to phosphoantigens but not to CMV. A third Vγ9negVδ2pos subgroup with adaptive functions has been described in adults. In the current study, we demonstrate that these Vγ9negVδ2pos T cells are also components of the CMV immune response while presenting with distinct characteristics from Vδ2neg γδ T cells. In a cohort of kidney transplant recipients, CMV seropositivity was the unique clinical parameter associated with Vγ9negVδ2pos T-cell expansion and differentiation. Extensive phenotyping demonstrated their substantial cytotoxic potential and activation during acute CMV primary infection or reinfection. In vitro, Vγ9negVδ2pos T cells responded specifically to CMV-infected cells in a T-cell receptor–dependent manner and through strong interferon γ production. Finally, Vγ9negVδ2pos T cells were the only γδ T-cell subset in which expansion was tightly correlated with the severity of CMV disease. To conclude, our results identify a new player in the immune response against CMV and open interesting clinical perspectives for using Vγ9negVδ2pos T cells as an immune marker for CMV disease severity in immunocompromised patients.

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Targeting of an activated T-cell subset using a bispecific antibody- toxin conjugate directed against CD4 and CD26

Blood ◽

10.1182/blood.v82.7.2224.bloodjournal8272224 ◽

1993 ◽

Vol 82 (7) ◽

pp. 2224-2234

Author(s):

JS Duke-Cohan ◽

C Morimoto ◽

SF Schlossman

Keyword(s):

T Cells ◽

T Cell ◽

B Cell ◽

Rational Design ◽

Bispecific Antibody ◽

Cell Subset ◽

Activated T Cells ◽

T Cell Subset ◽

Tissue Grafts ◽

Ig Synthesis

We have developed a bispecific antibody that recognizes the CD4 and CD26 antigens simultaneously and that was examined for its ability to target CD4+CD26+T cells. These latter cells constitute the activated component of the CD4+ CD29highCD45RO+ memory T-cell subset that provides help for B-cell Ig synthesis and help for responses against recall antigens. The purified bispecific antibody exhibited an estimated dissociation constant (kd) of 2.4 x 10(-9) mol/L, on comparison with 1.1 x 10(-9) mol/L for anti-CD26, and 1.6 x 10(-10) mol/L for anti-CD4. Surface plasmon resonance was used to show the bifunctional capacity of the antibody. On binding 125I-bispecific antibody to phytohemagglutinin (PHA)-activated T cells, 54.4% of the bound antibody was internalized. This was the result of bispecific binding, because monovalent fragments of anti-CD4 and anti-CD26 were not able to modulate antigen or induce internalization using both a fluorescent assay and an 125I-internalization assay. The ability of the bispecific antibody to be internalized was used to deliver a toxin, blocked ricin, specifically to cells that are CD4+CD26+. The inability of monovalent fragments to be internalized formed the basis for our hypothesis that monovalent binding by the bispecific immunotoxin would not result in internalization. Against resting E+ T cells, the bispecific immunotoxin developed a minimal effect. On preactivating the same cells, using phorbol myristate acetate (PMA)/ionomycin on concanavalin A (ConA) or especially PHA, levels of CD26 were upregulated and the immunotoxin effectively inhibited the ability to provide help for B-cell Ig synthesis while leaving intact the CD4-CD26+ and CD4+CD26- populations; an effect observed both functionally and by phenotype. The bispecific antibody proved to be most effective at inhibiting a heterologous mixed leukocyte reaction. We propose that this reagent may form the basis for the rational design of toxins designed to modulate activated T cells from, or directed against, tissue grafts.

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Faculty Opinions recommendation of A Macrophage Colony-Stimulating-Factor-Producing γδ T Cell Subset Prevents Malarial Parasitemic Recurrence.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.732635565.793573523 ◽

2020 ◽

Author(s):

David Wiest ◽

Alejandra Contreras

Keyword(s):

T Cell ◽

Cell Subset ◽

Γδ T Cell ◽

Colony Stimulating Factor ◽

T Cell Subset ◽

Macrophage Colony Stimulating Factor ◽

Macrophage Colony ◽

Stimulating Factor

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Targeting of an activated T-cell subset using a bispecific antibody- toxin conjugate directed against CD4 and CD26

Blood ◽

10.1182/blood.v82.7.2224.2224 ◽

1993 ◽

Vol 82 (7) ◽

pp. 2224-2234 ◽

Cited By ~ 6

Author(s):

JS Duke-Cohan ◽

C Morimoto ◽

SF Schlossman

Keyword(s):

T Cells ◽

T Cell ◽

B Cell ◽

Rational Design ◽

Bispecific Antibody ◽

Cell Subset ◽

Activated T Cells ◽

T Cell Subset ◽

Tissue Grafts ◽

Ig Synthesis

Abstract We have developed a bispecific antibody that recognizes the CD4 and CD26 antigens simultaneously and that was examined for its ability to target CD4+CD26+T cells. These latter cells constitute the activated component of the CD4+ CD29highCD45RO+ memory T-cell subset that provides help for B-cell Ig synthesis and help for responses against recall antigens. The purified bispecific antibody exhibited an estimated dissociation constant (kd) of 2.4 x 10(-9) mol/L, on comparison with 1.1 x 10(-9) mol/L for anti-CD26, and 1.6 x 10(-10) mol/L for anti-CD4. Surface plasmon resonance was used to show the bifunctional capacity of the antibody. On binding 125I-bispecific antibody to phytohemagglutinin (PHA)-activated T cells, 54.4% of the bound antibody was internalized. This was the result of bispecific binding, because monovalent fragments of anti-CD4 and anti-CD26 were not able to modulate antigen or induce internalization using both a fluorescent assay and an 125I-internalization assay. The ability of the bispecific antibody to be internalized was used to deliver a toxin, blocked ricin, specifically to cells that are CD4+CD26+. The inability of monovalent fragments to be internalized formed the basis for our hypothesis that monovalent binding by the bispecific immunotoxin would not result in internalization. Against resting E+ T cells, the bispecific immunotoxin developed a minimal effect. On preactivating the same cells, using phorbol myristate acetate (PMA)/ionomycin on concanavalin A (ConA) or especially PHA, levels of CD26 were upregulated and the immunotoxin effectively inhibited the ability to provide help for B-cell Ig synthesis while leaving intact the CD4-CD26+ and CD4+CD26- populations; an effect observed both functionally and by phenotype. The bispecific antibody proved to be most effective at inhibiting a heterologous mixed leukocyte reaction. We propose that this reagent may form the basis for the rational design of toxins designed to modulate activated T cells from, or directed against, tissue grafts.

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