Multiple-Cytokine-Producing Antiviral CD4 T Cells Are Functionally Superior to Single-Cytokine-Producing Cells

Abstract

Virus-specific CD4 T cells are endowed with multiple functions, such as cytokine production, CD40 ligand (CD40L) expression (associated with the costimulation of CD8 and B cells), and degranulation (associated with cytotoxic potential). Here, we used antiviral CD4 T cells present in human blood to evaluate the relationship between cytokine production and other functions of CD4 T cells. Antiviral CD4 T cells specific for a virus causing persistent infection, cytomegalovirus (CMV), and two viruses causing nonpersistent infections, influenza virus and the smallpox vaccine virus (vaccinia virus), were studied. CD4 T cells specific for each of the viruses produced all seven possible combinations of the cytokines gamma interferon (IFN-␥), interleukin-2, and tumor necrosis factor alpha. Cells producing three or two cytokines (triple producers and double producers) represented nearly 50% of the total response to each of the viruses. Triple producers expressed the highest levels of cytokines per cell, and single producers expressed the lowest. Following stimulation, higher frequencies of triple producers than single producers expressed CD40L. Only CMV-specific CD4 T cells underwent degranulation. However, higher frequencies of CMV-specific triple producers than single producers showed this functional characteristic. In contrast to the functional phenotypes, the memory phenotypes of triple producers and IFN-␥ single producers did not differ. These results demonstrate a strong positive association between the cytokine coproduction capacity of a virus-specific CD4 T cell and its other functional characteristics and suggest that vaccines should aim to elicit T cells that coproduce more than one cytokine. Antiviral CD4 T cells play a vital role in the control of many viral infections. CD4 T cells are critical for the generation of functional CD8 T cells and neutralizing antibody. CD8 T-cell priming in the absence of CD4 help results in the generation of CD8 T cells that are defective in their ability to expand following a secondary antigen exposure (7,15,22,24). CD4 T-cell help is also critical for the maintenance of functional CD8 responses (25). Similarly, CD4 T cells are crucial for the entry of B cells into germinal center reaction sites for affinity maturation, a process that facilitates the generation of neutralizing antibody and the formation of memory B cells (10,17).Characteristics that are important for T-cell function in the control of viral infections include the production of cytokines, such as gamma interferon (IFN-␥), interleukin-2 (IL-2), and tumor necrosis factor alpha (TNF-␣) (12, 23, 32), and proliferative capacity. Functional CD8 T-cell exhaustion is associated with a progressive loss of cytokine production and proliferative capacity, with the loss of IL-2 production being the first indicator of T-cell exhaustion, followed by the loss of TNF-␣ production (31). Apart from cytokine secretion, other indicators of CD4 T-cell function include costimulation via the expression of the CD40 ligand (CD40L) and cytot...

Human peripheral blood and bone marrow Epstein–Barr virus‐specific T‐cell repertoire in latent infection reveals distinct memory T‐cell subsets

“…4D) [36,49,50]. Other groups showed multicytokine-producing antiviral (CMV, influenza virus and vaccinia virus) T cells to posses in addition higher cytotoxic and costimulatory potential [50]. In accordance with the proposed differentiation model of Seder the CD8 1 triple cytokine producers in our study had an intermediate differentiation memory phenotype based on the CCR7 expression level (Fig.…”

“…Triple cytokine-producing T cells were described in previous studies to possess enhanced functionality characterized by high cytokine production [36,49,50] and cytotoxicity [50]. Comparing the MFI of triple with single cytokine-producing BM EBV-specific CD4 1 T cells, we confirm that triple cytokine-producing EBV-specific CD4 1 T cells exhibited an enhanced cytokine producing capacity with a two-to sixfold increased MFI (po0.05) (Fig.…”

“…In contrast, CD8 1 IFN-g 1 TNF 1 cells and CD4 1 IFN-g-producing cells (single or in combination) had lowest CCR7 expression, corresponding to a late-differentiated effector memory phenotype [48]. In the CD8 1 T-cell compartment, triple cytokine as well as IFN-g single-producing cells had a significantly higher CCR7 expression than IFN-g 1 TNF 1 producers.Triple cytokine-producing T cells were described in previous studies to possess enhanced functionality characterized by high cytokine production [36,49,50] and cytotoxicity [50]. Comparing the MFI of triple with single cytokine-producing BM EBV-specific CD4 1 T cells, we confirm that triple cytokine-producing EBV-specific CD4 1 T cells exhibited an enhanced cytokine producing capacity with a two-to sixfold increased MFI (po0.05) (Fig.…”

“…We could confirm the enhanced function of the triple cytokine cells by showing that they produce higher amounts of cytokines as compared to single producers (Fig. 4D) [36,49,50]. Other groups showed multicytokine-producing antiviral (CMV, influenza virus and vaccinia virus) T cells to posses in addition higher cytotoxic and costimulatory potential [50].…”

Dendritic cell targeted HIV‐1 gag protein vaccine provides help to a recombinant Newcastle disease virus vectored vaccine including mobilization of protective CD8+ T cells

“…T cells producing multiple cytokines appear to be especially effective in protective immunity 9, 28, 29, 30, 31 and have been associated with long term control of HIV‐1 in elite controllers. We therefore examined the quality of the T cell responses induced by complementary DC targeted protein and rNDV‐L‐gag vaccination in terms of the ability of the gag specific T cells to secrete multiple cytokines such as IFNγ, TNF‐α, and IL‐2 (polyfunctional T cells) .…”