Table 1.
Summary table of the main involvement of Vγ9Vδ2 T cells in infectious diseases.
| Infections | Human Vγ9Vδ2 T cells | Mechanisms of antimicrobial immunity | Vγ9Vδ2 T cell “memory” responses | |
|---|---|---|---|---|
| Bacteria | M. tuberculosis | ↑ in blood, bronchoalveolar lavage fluid and cerebral spinal fluid (5, 15, 16) ↓ loss of cytotoxic activity (61–63) |
- IFN-γ, TNF-α, perforin, granzymes, and granulysin release (64–66) - NKG2D activation (58) |
BCG vaccination: recall expansion in humans and in macaques (67) |
| L. monocytogenes | ↑ in blood (6) | - IFN-γ, TNF-α, IL-4, IL-17, and perforin release (68) |
L. monocytogenes secondary infection: recall expansion in macaques and in mice (69, 70) |
|
| Brucella spp. | ↑ in blood (8) | - IFN-γ and perforin release (71) - Fas-mediated signals (71) - NKG2D activation (58) |
Restore the full functional capacity of Brucella-infected DCs (72) | |
| Parasite | P. falciparum | ↑ in blood and spleens (20) ↓ loss of cytotoxic activity (12, 73) |
- IFN-γ, granzymes and granulysin release (74, 75) - phagocytosis (38) |
P. falciparum sporozoite vaccine: recall expansion associated with protection in humans (76, 77) |
| Virus | Influenza | Not known | - IFN-γ, perforin and granzymes release (78, 79) - TRAIL and Fas-mediated signals (78, 79) - NKG2D activation (78, 79) |
- Help to produce influenza virus-specific Ab (80, 81) - Influenza vaccination: memory responses (82, 83) |
| SARS-CoV | ↑ in blood after clearing SARS-CoV-1 and SARS-CoV-2 infections (21–23) |
- IFN-γ release (21) | Correlation with higher anti-SARS-CoV-1 specific IgG titers (21) | |
| Epstein-Barr | ↑ in blood (50) | - TRAIL and Fas mediated signals (84) - NKG2D activation (50, 84) |
Not known | |
| HBV/HCV | ↓ in blood in chronic hepatitis (24) inability of cytotoxic activity (85–87) |
- IFN-γ release (88) | Not known | |
| HIV | ↓ in blood and mucosal tissues inability of cytotoxic activity (25–27, 61) |
- ADCC mediated cytotoxicity (89) - production of antiviral factors that block HIV replication in vitro (90) |
- DC maturation and HIV-specific CD8+ T cell responses (91) - HIV Env-specific Ab titers during chronic SHIV (92) |
The arrow ↑ represents an increase and the arrow ↓ indicates a decrease in the number of Vγ9Vδ2 T cells.