Preclinical evaluation of HIV-1 therapeutic ex vivo dendritic cell vaccines expressing consensus Gag antigens and conserved Gag epitopes.
BACKGROUND
Dendritic cell (DC) therapy is a promising technology for the treatment of HIV infected individuals. HIV-1 Gag- and Nef RNA-loaded DC have previously been shown to induce immune responses ex vivo following coculture with autologous lymphocytes. However, polyfunctionality and memory responses following coculture have not been evaluated. In addition, little is known regarding whether specific HIV-1 proteome components, such as highly conserved regions of the HIV-1, could enhance clinical responses following DC therapy.


RESULTS
To determine the breadth of the immune responses to antigen loaded DC, we analyzed polyfunctional T cell response ex vivo to Gag RNA loaded DC. Blood samples were used to generate monocyte derived DC, which were then matured and cocultured with autologous lymphocytes. We found that cytokine-matured DC loaded with Gag RNA was able to induce Gag-specific IFN-γ and IL-2 responses after a 12-day coculture. We characterized these responses by polyfunctional intracellular cytokine staining and evaluation of T cell memory phenotypes. Central memory CD8+ T cells were induced ex vivo after DC coculture from each of 3 patients, and the effector memory pool was increased by DC coculture from 2 patients. We also observed a decrease in the terminal effector and intermediate CD8+ T cell pool and an increase in the naïve/other population. There was a reduction in terminal effector and intermediate CD4+ T cells, and a corresponding increase in naïve/other CD4+ T cells. Finally, we evaluated conserved regions of Gag as a novel DC therapy immunogen and found that a conserved element (CE) p24 Gag antigen elicited IFN-γ and IL-2 responses comparable to those induced by a full-length Gag antigen.


CONCLUSIONS
We showed that RNA-loaded DC therapy induced a polyfunctional T cell response ex vivo, supporting the use of such DC-therapy for HIV infection. However, the central and effector memory phenotypes of T cells did not appear to be enhanced during coculture with Gag RNA-loaded DC. Furthermore, comparable antigen-specific responses were induced in HIV infected individuals using full-length Gag or only conserved elements of the Gag p24 protein. This indicates that immune responses can be focused onto the conserved elements of Gag in the absence of other Gag components.
Department of Microbiology & Immunology, Miller School of Medicine, University of Miami, 1580 NW 10th Ave, Miami, FL, USA.
Liguo
L
Niu
James M
JM
Termini
Saravana K
SK
Kanagavelu
Sachin
S
Gupta
Morgane M
MM
Rolland
Viraj
V
Kulkarni
George N
GN
Pavlakis
Barbara K
BK
Felber
James I
JI
Mullins
Margaret A
MA
Fischl
Geoffrey W
GW
Stone
D016915:AIDS Vaccines / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D016655:HIV Core Protein p24 / Q000276:immunology; D015658:HIV Infections / Q000276:immunology / Q000628:therapy*; D015497:HIV-1 / Q000235:genetics / Q000276:immunology; D006801:Humans; D007156:Immunologic Memory; D007371:Interferon-gamma / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D012367:RNA, Viral / Q000235:genetics; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000276:immunology*
D016915:AIDS Vaccines; D016655:HIV Core Protein p24; C508594:IL2 protein, human; D007376:Interleukin-2; D012367:RNA, Viral; D054301:gag Gene Products, Human Immunodeficiency Virus; C514799:p24 protein, Human Immunodeficiency Virus Type 1; D007371:Interferon-gamma
AIDS Res Hum Retroviruses. 2009 Mar;25(3):297-303
19327049
J Intern Med. 2009 Jan;265(1):138-58
19093966
J Exp Med. 2006 Jun 12;203(6):1533-41
16735692
J Immunol. 2008 May 1;180(9):5907-15
18424710
J Infect Dis. 2009 Jun 15;199(12):1862-71
19419334
J Immunol. 1998 Aug 15;161(4):1686-93
9712032
Immunol Rev. 2004 Jun;199:251-63
15233739
Clin Immunol. 2008 Mar;126(3):235-42
17916442
Nat Rev Drug Discov. 2010 Jul;9(7):513-4
20592741
Blood. 2010 Nov 11;116(19):3839-52
20693428
J Acquir Immune Defic Syndr. 2010 Mar;53(3):303-10
20048679
Nat Immunol. 2007 Nov;8(11):1246-54
17906628
AIDS. 2003 Dec 5;17(18):2581-91
14685052
Mol Ther. 2010 Nov;18(11):2028-37
20648001
J Virol. 2008 Apr;82(7):3561-73
18234800
J Immunol. 2009 Apr 1;182(7):4244-54
19299723
Blood. 2006 Mar 1;107(5):1963-9
16249391
PLoS One. 2010 Sep 01;5(9):
20824187
Nat Med. 2004 Mar;10(3):282-9
14770175
PLoS Comput Biol. 2007 Apr 27;3(4):e75
17465674
Blood. 2003 Jan 1;101(1):226-35
12393740
J Virol. 2008 Apr;82(7):3391-404
18199637
Nat Med. 2006 Oct;12(10):1198-202
16917489
J Leukoc Biol. 2003 Nov;74(5):702-9
12960257
Prostate. 2009 Jun 15;69(9):938-48
19267351
Clin Immunol. 2010 Feb;134(2):140-7
19889582
Proc Natl Acad Sci U S A. 2010 Aug 3;107(31):13824-9
20631300
J Immunol. 1999 Jun 1;162(11):6942-6
10352317
AIDS Rev. 2008 Jan-Mar;10(1):36-46
18385779
J Infect Dis. 2009 Dec 15;200(12):1825-33
19909083
PLoS Pathog. 2007 Nov;3(11):e157
18052528
Science. 2006 Jun 9;312(5779):1530-3
16763152
J Exp Med. 2007 Jun 11;204(6):1405-16
17535971