Table 1. Immune memory responses of gamma delta (γδ) T cells.

BCG: Bacille Calmette-Guerin; CMV: Cytomegalovirus; HSV: herpes simplex virus; IMQ: imiquimod; MMR: measles-mumps-rubella; MPV: Mpox virus.

Species	T cell subset	Experimental setting	Location	Adaptive immune memory responses		Innate immune memory responses		Ref
				Inducing agent	Immune memory response characteristics	Inducing agent	Immune memory response characteristics
Human and non-human primates	Vδ2	In vitro	Peripheral blood	BCG	Enhanced proliferation upon M. tuberculosis stimulation			Hoft et al., 1998; Kabelitz et al., 1991
	Vδ2	In vivo	Peripheral blood	BCG	Enhanced proliferation and IFN-γ production upon restimulation			Kabelitz et al., 1991
	γδ	In vivo	Pulmonary and peripheral blood	BCG	Enhanced proliferation upon reinfection			Shen et al., 2002; Lai et al., 2003
	Vδ2	In vivo	Peripheral blood	Listeria monocytogenes	Enhanced proliferation and effector function upon reinfection			Ryan-Payseur et al., 2012
	γδ	In vivo	Peripheral blood	Plasmodium falciparum	Enhanced proliferation and IFN-γ production upon restimulation			Teirlinck et al., 2011
	Vδ1	In vivo	Peripheral blood	Plasmodium falciparum	Clonal expansion, recurrent parasite-exposure driven expansion and differentiation			von Borstel et al., 2021; Rutishauser et al., 2020
	Vδ2	In vivo	Peripheral blood	SARS-CoV-2 mRNA vaccine	Enhanced proliferation and IFN-γ production upon revaccination			Terzoli et al., 2024
	Vδ2	In vivo	Peripheral blood	MPV	Enhanced proliferation and IFN-γ production upon rechallenge			Shao et al., 2009
	Vδ1	In vivo	Peripheral blood	CMV	Rapid proliferation and infection resolution after reinfection			Pitard et al., 2008
	Vδ2	In vivo	Pulmonary compartment			Listeria monocytogenes	Enhanced IFN-γ and perforin production; lower pulmonary pathology and less weight loss upon M. tuberculosis infection	Shen et al., 2019
	γδ	In vitro	Peripheral blood			BCG	Enhanced TNF and IFN-γ production upon C. albican challenge; transcriptional rewiring	Suen et al., 2024
	Vδ2	In vitro	Peripheral blood			HSV	Enhanced lysing ability of infected cells upon PHA or mycobacteria stimulation	Bukowski et al., 1994
	γδ	In vitro	Peripheral blood			MMR	Enhanced TNF and IFN-γ production upon CD3 stimulation; transcriptional and metabolic rewiring	Röring et al., 2024
Mouse	Vγ4Vδ1	In vivo	Intestinal mucosa	Listeria monocytogenes	Enhanced proliferation and infection clearance upon rechallenge			Sheridan et al., 2013
	Vγ4	In vivo	Intestinal epithelium	Listeria monocytogenes	Enhanced IL-17 production and clustering with L monocytogenes replication foci upon secondary infection			Romagnoli et al., 2016
	Vγ6	In vivo	Peritoneum, draining mediastinal lymph nodes	Staphylococcus aureus	Enhanced IL-17 production and infection clearance after reinfection			Murphy et al., 2014
	Vγ6	In vivo	Kidney	Staphylococcus aureus	Reduced renal bacterial load upon reinfection			Bertram et al., 2023
	Vγ1	In vivo	Liver, lung, spleen	MCMV	Enhanced proliferation and survival rate upon rechallenge			Khairallah et al., 2015
	γδ	In vitro	Liver, spleen	Plasmodium chabaudi	Enhanced CD107a expression and IFN-γ production upon rechallenge; transcriptional reprogramming			Kumarasingha et al., 2020
	Vγ4Vδ4	In vivo	Skin			IMQ	Enhanced proliferation and IL-17 production upon IMQ rechallenge	Ramírez-Valle et al., 2015
	Vγ4Vδ4	In vivo	Skin; ear			IMQ	Enhanced proliferation and IL-17 production and neutrophil recruitment upon IMQ rechallenge	Hartwig et al., 2015
	Vγ4Vδ1	In vitro	Gut; bulk mesenteric lymph nodes			Listeria monocytogenes	Enhanced proliferation and IFN-γ and IL-17A production upon S. enterica serovar Typhimurium and C. rodentium challenge	Khairallah et al., 2022
Cow	γδ	In vitro	Airway and peripheral blood	BCG	Increased IFN-γ producing γδ T cells			Guerra-Maupome and McGill, 2019
	γδ	In vitro	Peripheral blood			BCG	Enhanced IL-6 and TNF production upon Escherichia coli, LPS and Pam3CSK4 stimulation; epigenetic rewiring	Samuel et al., 2024