Gut-homing Δ42PD1+Vδ2 T cells promote innate mucosal damage via TLR4 during acute HIV type 1 infection

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The innate immune cells underlying mucosal inflammatory responses and damage during acute HIV-1 infection remain incompletely understood. Here, we report a Vδ2 subset of gut-homing γδ T cells with significantly upregulated Δ42PD1 (a PD1 isoform) in acute (~20%) HIV-1 patients compared to chronic HIV-1 patients (~11%) and healthy controls (~2%). The frequency of Δ42PD1+Vδ2 cells correlates positively with plasma levels of pro-inflammatory cytokines and fatty-acid-binding protein before detectable lipopolysaccharide in acute patients. The expression of Δ42PD1 can be induced by in vitro HIV-1 infection and is accompanied by high co-expression of gut-homing receptors CCR9/CD103. To investigate the role of Δ42PD1+Vδ2 cells in vivo, they were adoptively transferred into autologous humanized mice, resulting in small intestinal inflammatory damage, probably due to the interaction of Δ42PD1 with its cognate receptor Toll-like receptor 4 (TLR4). In addition, blockade of Δ42PD1 or TLR4 successfully reduced the cytokine effect induced by Δ42PD1+Vδ2 cells in vitro, as well as the mucosal pathological effect in humanized mice. Our findings have therefore uncovered a Δ42PD1–TLR4 pathway exhibited by virus-induced gut-homing Vδ2 cells that may contribute to innate immune activation and intestinal pathogenesis during acute HIV-1 infection. Δ42PD1+Vδ2 cells may serve as a target for the investigation of diseases with mucosal inflammation.

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Fig. 1: Δ42PD1+Vδ2 cells are found in early HIV-1 infection and correlate with immune activation.
Fig. 2: HIV-1 infection induces Δ42PD1 expression on Vδ2 cells.
Fig. 3: Preferential migration of HIV-induced CD3+Vδ2+ cells to the intestines in humanized mice.
Fig. 4: Δ42PD1 functions via TLR4 for the induction of cytokine production.
Fig. 5: Direct interaction between Δ42PD1 and TLR4.
Fig. 6: HIV-induced Δ42PD1-expressing γδ T cells can induce robust cytokines from autologous DCs via Δ42PD1–TLR4.


  1. 1.

    Vantourout, P. & Hayday, A. Six-of-the-best: unique contributions of γδ T cells to immunology. Nat. Rev. Immunol. 13, 88–100 (2013).

  2. 2.

    McCarthy, N. E. et al. Proinflammatory Vδ2+ T cells populate the human intestinal mucosa and enhance IFN-γ production by colonic αβ T cells. J. Immunol. 191, 2752–2763 (2013).

  3. 3.

    McCarthy, N. E. et al. Azathioprine therapy selectively ablates human Vδ2(+) T cells in Crohn’s disease. J. Clin. Invest. 125, 3215–3225 (2015).

  4. 4.

    Brandes, M., Willimann, K. & Moser, B. Professional antigen-presentation function by human γδ T cells. Science 309, 264–268 (2005).

  5. 5.

    Bjarnason, I. et al. Intestinal inflammation, ileal structure and function in HIV. AIDS 10, 1385–1391 (1996).

  6. 6.

    Batman, P. A. et al. Jejunal enteropathy associated with human immunodeficiency virus infection: quantitative histology. J. Clin. Pathol. 42, 275–281 (1989).

  7. 7.

    Heise, C. et al. Primary acute simian immunodeficiency virus infection of intestinal lymphoid tissue is associated with gastrointestinal dysfunction. J. Infect. Dis. 169, 1116–1120 (1994).

  8. 8.

    Kotler, D. P., Reka, S. & Clayton, F. Intestinal mucosal inflammation associated with human immunodeficiency virus infection. Dig. Dis. Sci. 38, 1119–1127 (1993).

  9. 9.

    McGowan, I. et al. Increased HIV-1 mucosal replication is associated with generalized mucosal cytokine activation. J. Acquir. Immune Defic. Syndr. 37, 1228–1236 (2004).

  10. 10.

    Olsson, J. et al. Human immunodeficiency virus type 1 infection is associated with significant mucosal inflammation characterized by increased expression of CCR5, CXCR4, and β-chemokines. J. Infect. Dis. 182, 1625–1635 (2000).

  11. 11.

    Harouse, J. M. et al. Distinct pathogenic sequela in rhesus macaques infected with CCR5 or CXCR4 utilizing SHIVs. Science 284, 816–819 (1999).

  12. 12.

    Autran, B. et al. T cell receptor γ/δ+ lymphocyte subsets during HIV infection. Clin. Exp. Immunol. 75, 206–210 (1989).

  13. 13.

    Gan, Y. H., Pauza, C. D. & Malkovsky, M. γδ T cells in rhesus monkeys and their response to simian immunodeficiency virus (SIV) infection. Clin. Exp. Immunol. 102, 251–255 (1995).

  14. 14.

    Poles, M. A. et al. Human immunodeficiency virus type 1 induces persistent changes in mucosal and blood T cells despite suppressive therapy. J. Virol. 77, 10456–10467 (2003).

  15. 15.

    Glatzel, A. et al. Patterns of chemokine receptor expression on peripheral blood γδ T lymphocytes: strong expression of CCR5 is a selective feature of Vδ2/Vγ9 γδ T cells. J. Immunol. 168, 4920–4929 (2002).

  16. 16.

    Li, H. & Pauza, C. D. HIV envelope-mediated, CCR5/α4β7-dependent killing of CD4-negative γδ T cells which are lost during progression to AIDS. Blood 118, 5824–5831 (2011).

  17. 17.

    Hermier, F. et al. Decreased blood TcR γδ+ lymphocytes in AIDS and p24-antigenemic HIV-1-infected patients. Clin. Immunol. Immunopathol. 69, 248–250 (1993).

  18. 18.

    Kosub, D. A. et al. γδ T-cell functional responses differ after pathogenic human immunodeficiency virus and nonpathogenic simian immunodeficiency virus infections. J. Virol. 82, 1155–1165 (2008).

  19. 19.

    Li, Z. et al. γδ T cells are involved in acute HIV infection and associated with AIDS progression. PLoS ONE 9, e106064 (2014).

  20. 20.

    Poccia, F. et al. Peripheral Vγ9/Vδ2 T cell deletion and anergy to nonpeptidic mycobacterial antigens in asymptomatic HIV-1-infected persons. J. Immunol. 157, 449–461 (1996).

  21. 21.

    Wallace, M. et al. Functional γδ T-lymphocyte defect associated with human immunodeficiency virus infections. Mol. Med. 3, 60–71 (1997).

  22. 22.

    Cardone, M. et al. HIV-1-induced impairment of dendritic cell cross-talk with γδ T lymphocytes. J. Virol. 89, 4798–4808 (2015).

  23. 23.

    Cimini, E. et al. Primary and chronic HIV infection differently modulates mucosal Vδ1 and Vδ2 T-cells differentiation profile and effector functions. PLoS ONE 10, e0129771 (2015).

  24. 24.

    Zhou, J. et al. Potentiating functional antigen-specific CD8+ T cell immunity by a novel PD1 isoform-based fusion DNA vaccine. Mol. Ther. 21, 1445–1455 (2013).

  25. 25.

    Cheng, L. et al. Monoclonal antibodies specific to human Δ42PD1: a novel immunoregulator potentially involved in HIV-1 and tumor pathogenesis. MAbs 7, 620–629 (2015).

  26. 26.

    Stacey, A. R. et al. Induction of a striking systemic cytokine cascade prior to peak viremia in acute human immunodeficiency virus type 1 infection, in contrast to more modest and delayed responses in acute hepatitis B and C virus infections. J. Virol. 83, 3719–3733 (2009).

  27. 27.

    Brenchley, J. M. et al. Microbial translocation is a cause of systemic immune activation in chronic HIV infection. Nat. Med. 12, 1365–1371 (2006).

  28. 28.

    García, V. E. et al. IL-15 enhances the response of human γδ T cells to nonpetide microbial antigens. J. Immunol. 160, 4322–4329 (1998).

  29. 29.

    Enders, P. J. et al. HIV-mediated γδ T cell depletion is specific for Vγ2+ cells expressing the Jγ1.2 segment. AIDS Res. Hum. Retroviruses 19, 21–29 (2003).

  30. 30.

    Evans, P. S. et al. In vitro stimulation with a non-peptidic alkylphosphate expands cells expressing Vγ2-Jγ1.2/Vδ2 T-cell receptors. Immunology 104, 19–27 (2001).

  31. 31.

    Hebbeler, A. M. et al. Failure to restore the Vγ2-Jγ1.2 repertoire in HIV-infected men receiving highly active antiretroviral therapy (HAART). Clin. Immunol. 128, 349–357 (2008).

  32. 32.

    Wu, X. et al. Brain invasion by CD4+ T cells infected with a transmitted/founder HIV-1 during acute stage in humanized mice. J. Neuroimmune Pharmacol. 11, 572–583 (2016).

  33. 33.

    Abreu, M. T., Fukata, M. & Arditi, M. TLR signaling in the gut in health and disease. J. Immunol. 174, 4453–4460 (2005).

  34. 34.

    Balazs, A. B. et al. Vectored immunoprophylaxis protects humanized mice from mucosal HIV transmission. Nat. Med. 20, 296–300 (2014).

  35. 35.

    Im, E. et al. Elevated lipopolysaccharide in the colon evokes intestinal inflammation, aggravated in immune modulator-impaired mice. Am. J. Physiol. Gastrointest. Liver Physiol. 303, G490–G497 (2012).

  36. 36.

    Erridge, C. Endogenous ligands of TLR2 and TLR4: agonists or assistants? J. Leukoc. Biol. 87, 989–999 (2010).

  37. 37.

    Teghanemt, A. et al. Novel roles in human MD-2 of phenylalanines 121 and 126 and tyrosine 131 in activation of Toll-like receptor 4 by endotoxin. J. Biol. Chem. 283, 1257–1266 (2008).

  38. 38.

    Yu, L. et al. NMR studies of hexaacylated endotoxin bound to wild-type and F126A mutant MD-2 and MD-2.TLR4 ectodomain complexes. J. Biol. Chem. 287, 16346–16355 (2012).

  39. 39.

    Schromm, A. B. et al. Molecular genetic analysis of an endotoxin nonresponder mutant cell line: a point mutation in a conserved region of MD-2 abolishes endotoxin-induced signaling. J. Exp. Med. 194, 79–88 (2001).

  40. 40.

    Gruber, A. et al. Structural model of MD-2 and functional role of its basic amino acid clusters involved in cellular lipopolysaccharide recognition. J. Biol. Chem. 279, 28475–28482 (2004).

  41. 41.

    Apetoh, L. et al. Toll-like receptor 4-dependent contribution of the immune system to anticancer chemotherapy and radiotherapy. Nat. Med. 13, 1050–1059 (2007).

  42. 42.

    Andersson, U. & Tracey, K. J. HMGB1 is a therapeutic target for sterile inflammation and infection. Annu. Rev. Immunol. 29, 139–162 (2011).

  43. 43.

    Pal, D. et al. Fetuin-A acts as an endogenous ligand of TLR4 to promote lipid-induced insulin resistance. Nat. Med. 18, 1279–1285 (2012).

  44. 44.

    Schmidt, M. et al. Crucial role for human Toll-like receptor 4 in the development of contact allergy to nickel. Nat. Immunol. 11, 814–819 (2010).

  45. 45.

    Conti, L. et al. Reciprocal activating interaction between dendritic cells and pamidronate-stimulated γδ T cells: role of CD86 and inflammatory cytokines. J. Immunol. 174, 252–260 (2005).

  46. 46.

    Scotet, E. et al. Bridging innate and adaptive immunity through γδ T-dendritic cell crosstalk. Front. Biosci. 13, 6872–6885 (2008).

  47. 47.

    Mancek-Keber, M. & Jerala, R. Postulates for validating TLR4 agonists. Eur. J. Immunol. 45, 356–370 (2015).

  48. 48.

    Park, B. S. et al. The structural basis of lipopolysaccharide recognition by the TLR4-MD-2 complex. Nature 458, 1191–1195 (2009).

  49. 49.

    Rakoff-Nahoum, S. et al. Recognition of commensal microflora by Toll-like receptors is required for intestinal homeostasis. Cell 118, 229–241 (2004).

  50. 50.

    Chen, Z. et al. CD4+ lymphocytopenia in acute infection of Asian macaques by a vaginally transmissible subtype-C, CCR5-tropic simian/human immunodeficiency virus (SHIV). J. Acquir. Immune Defic. Syndr. 30, 133–145 (2002).

  51. 51.

    Mattapallil, J. J. et al. Massive infection and loss of memory CD4+ T cells in multiple tissues during acute SIV infection. Nature 434, 1093–1097 (2005).

  52. 52.

    Raffatellu, M. et al. Simian immunodeficiency virus-induced mucosal interleukin-17 deficiency promotes Salmonella dissemination from the gut. Nat. Med. 14, 421–428 (2008).

  53. 53.

    Mancek-Keber, M. et al. Toll-like receptor 4 senses oxidative stress mediated by the oxidation of phospholipids in extracellular vesicles. Sci. Signal. 8, ra60 (2015).

  54. 54.

    Zidar, D. A. et al. Oxidized LDL levels are increased in HIV infection and may drive monocyte activation. J. Acquir. Immune Defic. Syndr. 69, 154–160 (2015).

  55. 55.

    Brandes, M. et al. Cross-presenting human γδ T cells induce robust CD8+ αβ T cell responses. Proc. Natl Acad. Sci. USA 106, 2307–2312 (2009).

  56. 56.

    Poonia, B. et al. γδ T cells are ADCC effectors in elite HIV controllers. Retrovirology 7(Suppl 1), O7 (2010).

  57. 57.

    González-Navajas, J. M. et al. TLR4 signaling in effector CD4+ T cells regulates TCR activation and experimental colitis in mice. J. Clin. Invest. 120, 570–581 (2010).

  58. 58.

    Jin, B. et al. The effects of TLR activation on T-cell development and differentiation. Clin. Dev. Immunol. 2012, 836485 (2012).

  59. 59.

    Tu, W. et al. The aminobisphosphonate pamidronate controls influenza pathogenesis by expanding a γδ T cell population in humanized mice. J. Exp. Med. 208, 1511–1522 (2011).

  60. 60.

    Xiang, Z. et al. Targeted activation of human Vγ9Vδ2-T cells controls Epstein–Barr virus-induced B cell lymphoproliferative disease. Cancer Cell 26, 565–576 (2014).

  61. 61.

    Kang, Y. et al. CCR5 antagonist TD-0680 uses a novel mechanism for enhanced potency against HIV-1 entry, cell-mediated infection, and a resistant variant. J. Biol. Chem. 287, 16499–16509 (2012).

  62. 62.

    Cheung, A. K. L. et al. The role of the human cytomegalovirus UL111A gene in down-regulating CD4+ T-cell recognition of latently infected cells: implications for virus elimination during latency. Blood 114, 4128–4137 (2009).

  63. 63.

    Ghosh, J. K., Romanow, W. J. & Murre, C. Induction of a diverse T cell receptor γ/δ repertoire by the helix-loop-helix proteins E2A and HEB in nonlymphoid cells. J. Exp. Med. 193, 769–776 (2001).

  64. 64.

    van Dongen, J. J. et al. Design and standardization of PCR primers and protocols for detection of clonal immunoglobulin and T-cell receptor gene recombinations in suspect lymphoproliferations: report of the BIOMED-2 Concerted Action BMH4-CT98-3936. Leukemia 17, 2257–2317 (2003).

  65. 65.

    Lefranc, M. P. et al. IMGT®, the international ImMunoGeneTics information system® 25 years on. Nucleic Acids Res. 43, D413–D422 (2015).

  66. 66.

    Weigmann, B. et al. Isolation and subsequent analysis of murine lamina propria mononuclear cells from colonic tissue. Nat. Protoc. 2, 2307–2311 (2007).

  67. 67.

    Erben, U. et al. A guide to histomorphological evaluation of intestinal inflammation in mouse models. Int. J. Clin. Exp. Pathol. 7, 4557–4576 (2014).

  68. 68.

    Feinman, R. et al. HIF-1 mediates pathogenic inflammatory responses to intestinal ischemia–reperfusion injury. Am. J. Physiol. Gastrointest. Liver Physiol. 299, G833–G843 (2010).

  69. 69.

    Karpova, T. & McNally, J. G. Detecting protein–protein interactions with CFP-YFP FRET by acceptor photobleaching. Curr. Protoc. Cytom. 12, 12.7.1–12.7.11 (2007).

  70. 70.

    Feige, J. N. et al. PixFRET, an ImageJ plug-in for FRET calculation that can accommodate variations in spectral bleed-throughs. Microsc. Res. Tech. 68, 51–58 (2005).

  71. 71.

    Nicoludis, J. M. et al. Structure and sequence analyses of clustered protocadherins reveal antiparallel interactions that mediate homophilic specificity. Structure 23, 2087–2098 (2015).

  72. 72.

    Kozakov, D. et al. The ClusPro web server for protein–protein docking. Nat. Protoc. 12, 255–278 (2017).

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The authors thank K. Miyake for providing the MD2 plasmid, K.H. Kok for CFP, YFP and NF-κB-luciferase plasmids and C. Cheng-Mayer for critical discussions. The authors thank L. Liu for technical advice with immunohistochemical staining. The authors acknowledge the Faculty Core Facility of the LKS Faculty of Medicine, HKU, for technical assistance with confocal microscopy. This work was supported by research grants from the Hong Kong Research Grant Council (RGC: HKU5/CRF/13G, RGC17103514, RGC17122915 and A-HKU709/14 to Z.C.); the Health and Medical Research Fund (HMRF: 14130582 to Z.C., 15140372 to A.K.L.C.); the San-Ming Project of Medicine in Shenzhen (to Z.C. and H.Wa.); the National Science and Technology Major Project (2012ZX10001-009-001-001 to Z.C., 2012ZX1000-1006-001-009 to H.S.) Beijing Key Laboratory of HIV/AIDS Research (BZ0089 to H.Wu) and Beijing Municipal of Science and Technology Major Project (D161100000416003 to H.Wu) and the University Development Fund of the University of Hong Kong and Li Ka Shing Faculty of Medicine Matching Fund to AIDS Institute.

Author information

A.K.L.C. and Z.C. designed experiments, analysed data and wrote the manuscript. A.K.L.C., Y.H., H.-y.K., M.C., Y.M., X.W., K.-s.L., H.-k.K, T.C.K.L., J.Z. and B.K.L. performed experiments. J.L. and L.C. generated the Δ42PD1-specific antibodies. Q.P., X.L., M.A., H.Wa., H.S., B.Z. and H.Wu provided HIV patient samples. A.X. and K.-Y.Y. provided critical comments and materials.

Correspondence to Zhiwei Chen.

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