The present invention relates, in general, to human immunodeficiency virus (HIV) and, in particular, to a multicomponent vaccine and method of using same to protect against HIV-1 infection.
Production of an effective vaccine for HIV-1 is a critical goal of AIDS research. To date, development of a preventive vaccine has been unsuccessful due to the diversity of HIV (Gaschen, Science 296:2354 (2002)), the rapid onset of apoptosis of immune cells at mucosal sites (Mattapallil et al, Nature 434:1093 (2005); Veazey et al, Science 280:427 (1998); Guadalupe et al, J. Virol 77:11708 (2003); Brenchley et al, J. Exp. Med. 200:749 (2004); Menhandru et al, J. Exp. Med. 200:761 (2004)), the fact that HIV-1 is an integrating virus with a viral cellular reservoir (Fauci, Science 245:305 (1989)), and the delay in induction of autologous HIV-1 innate and neutralizing antibody responses from eight weeks to a year following viral ramp-up in the plasma (Abel et al, J. Virol 80:6357-67 (2006), Wei et al, Nature 422:307-12 (2003); Richman et al, Proc. Natl. Acad. Sci. USA 100:4144-9 (2003)).
The present invention relates to a multicomponent vaccine that addresses problems resulting from the diversity of HIV by the use consensus and/or mosaic HIV genes (Gaschen et al, Science 296:2354 (2002); Liao et al, Virology 353:268 (2006), Gao et al, J. Virol. 79:1154 (2005), Weaver et al, J. Virol. 80:6754 (2006), Fischer et al, Nature Medicine, 13(1):100-106 (2007), Epub 2006 Dec. 24), coupled with strategies designed to break immune tolerance to allow for induction of the desired specificity of neutralzing antibodies at mucosal sites (e.g., through the use of T regulatory cell inhibition and/or TLR-9 agonist adjuvants), and strategies designed to overcome HIV-1 induced apoptosis (e.g., induction of anti-phosphatidylserine (PS) antibodies, anti-CD36 antibodies, and/or anti-tat antibodies).
The present invention relates generally to HIV. More specifically, the invention relates to a multicomponent HIV vaccine that can be used to protect humans against HIV-1 infection.
Objects and advantages of the present invention will be clear from the description that follows.
Methods. Phospholipids POPC (1-Palmitoyl-2-Oleoyl-sn-Glycero-3-Phosphatidylcholine), POPE (1-Palmitoyl-2-Oleoyl-sn-Glycero-3-Phosphatidylethanolamine), DOPE (1,2-Dioleoyl-sn-Glycero-3-Phosphatidylethanolamine); DMPA (1,2-Dimyristoyl-sn-Glycero-3-Phosphate) and Cholesterol dissolved in chloroform were purchased from Avanti Polar Lipids (Alabaster, Ala.). Phospholipid liposomes were prepared by dispensing appropriate molar amounts of phospholipids in chloroform resistant tubes. Chloroform solutions of lipids were added to the peptide solution, in molar ratios of 45:25:20:10 (POPC:POPE:DMPA:Cholesterol). HIV-1 membrane proximal peptides were dissolved in 70% Chloroform, 30% Methanol. Each peptide was added to a molar ratio of peptide:total phospholipids of 1:420. The phospholipids were mixed by gentle vortexing and the mixture was dried in the fume hood under a gentle stream of nitrogen. Any residual chloroform was removed by storing the lipids under a high vacuum (15 h). Aqueous suspensions of phospholipids were prepared by adding PBS or TBS buffer, pH 7.4 and kept at a temperature above the Tm for 10-30 minutes, with intermittent, vigorous vortexing to resuspend the phospholipids followed by Sonication in a bath sonicator (Misonix Sonicator 3000, Misonix Inc., Farmingdale, N.Y.). The sonicator was programmed to run 3 consecutive cycles of 45 seconds of total sonication per cycle. Each cycle included 5 seconds of sonication pulse (70 watts power output) followed by a pulse off period of 12 seconds. At the end of sonication, the suspension of lamellar liposomes was stored at 4° C. and was thawed and sonicated again as described above prior to capture on BLAcore sensor chip.
Peptides were synthesized and purified by reverse-phase HPLC and purity was confirmed by mass spectrometric analysis. Peptides used in this study include the following—
The present invention relates to a multicomponent, multifunctional HIV vaccine targeted at overcoming: i) HIV diversity, ii) tolerance constraints of neutralizing antibody induction, and iii) apoptotic induced immunosuppression. The invention provides an HIV vaccine comprising centralized HIV gene inserts (consensus, mosaic), a tolerance-breaking component (e.g. TLR-agonists, T regulatory cell innhibition), and a component that can inhibit the immunosuppression of apoptotsis, or inhibit apoptosis itself (e.g., anti-PS, anti-CD36 antibody induction, and/or anti-HIV tat antibody induction).
The use of adjuvants and other immunization regimens that result in antibody specificities being made that are not ordinarily made to HIV-1 envelope immunization have been proposed previously (PCT/US2006/013684; U.S. application Ser. No. 11/785,007; U.S. application Ser. No. 11/812,992; U.S. Prov. Application No. 60/960,413). This work derived from the observation that many of the broadly neutralizing anti-HIV-1 monoclonal antibodies are autoantibodies and are likely under immunoregulatory control (Haynes et al, Science 308:1906 (2005), Haynes et al, Human Antibodies 14:59 (2006)). One adjuvant regimen that has been used to break tolerance in mice is oligo CpGs in an oil-based adjuvant (Tran et al, Clin. Immunol. 109:278 (2003)). For humans, the B type of oligo CpGs can be used, including 2006 or 10103 oCpGs (McCluskie and Krieg, Curr. Topic. Microbial. Immunol. 311:155-178 (2006)). However, tolerance controls can be difficult to completely overcome, even on a temporary basis, and autoantibody production is also under T regulatory cell control (Shevach, Immunity 25:195-201 (2006)). Tnus, immunization with an adjuvant regimen combined with a regimen to temporarily inactivate T regulatory cells can be used to induce anti-HIV-1 antibodies that normally are prevented from being induced by negative immunoregulatory mechanisms. T regulatory cells can be inactivated or eliminated by either immunizing with glucocorticoid-induced TNT family-related receptor ligand (GITRL) DNA (Stone et al, J. Virol. 80:1762-72 (2006)), CD40 Ligand DNA (Stone et al, Clin. Vaccine Immunol. 13:1223-30 (2006), or administering simultaneously with the vaccine immunization a CD25 mab or ONTAK, a IL-2-toxin conjugate (see PCT/US2005/37384, PCT/US06/47591, U.S. application Ser. No. 11/302,505 and U.S. application Ser. No. 11/665,251) (the data presented in Example 2 below demonstrates that administration of ONTAK to rhesus monkeys enhances antibody generation to an antigen).
A further approach to breaking tolerance to administered immunogens is to design the recombinant insert genes with a cytoplasmic domain endoplasmic reticulum retention sequence, such as lysine-lysine, and target the HIV gene (such as Envelope) for retention in the endoplasmic reticulum (Cornall et al, JEM 198:1415-25 (2003)). Such a designed gene can be, for example, a DNA, recombinant adenovirus immunogen or a DNA, recombinant vesicular stomatitis virus immunogen or combinations thereof. Any of a variety of other vectors can also be used to deliver the insert genes (e.g., those presented in Table 1):
AGSTMGAASI
T
LTVQARQLLSGIVQQQSNLLRAIEAQQHLLQLTVWG
IKQLQARVLAVERYLKDQQLLGIWGCSGKLICTTTVPWNSSWSNKSQ
DEIWDNMTWMEWEREINNYTDIIYSLIEESQNQQEKNEQELLALDKW
ASLWNWFDITNWLWYIKIFIMIVGGLIGLRIVFAVLSIVNRVRQGYS
AGSTMGAASI
T
LTVQARQLLSGIVQQQSNLLRAIEAQQHLLQLTVWG
IKMQARVLAVERYLKDQQLLGIWGCSGKLICTTTVPWNSSWSNKSQD
SLWNWFDITNWLWYIKIFIMIVGGLIGLRIVFAVLSIVNRVRQGYSP
AGSTMGAASI
T
LTVQARQLLSGIVQQQSNLLRAIEAQQHLLQLTVWG
IKQLQARVLAVERYLKDQQLLGIWGCSGKLICTTTVPWNSSWSNKSQ
DEIWDNMTWMEWEREINNYTDIIYSLIEESQNQQEKNEQELLALDKW
ASLWNWFDITNWLWYIKIFIMIVGGLIGLRIVFAVLSIVNRVRQGYS
AGSTMGAASI
T
LTVQARQLLSGIVQQQSNLLRAIEAQQHLLQLTVWG
IKQLQARVLAVERYLKDQQLLGIWGCSGKLICTTTVPWNSSWSNKSQ
DEIWDNMTWMEWEREINNYTDIIYSLIEESQNQQEKNEQELLALDKW
ASLWNWFDITNWLWYIKIFIMIVGGLIGLRIVFAVLSIVNRVRQGYS
GSTMGAASM
TLTVQARLLLSGIVQQQNNLLRAIEAQQRMLQLTVWGI
KQLQARVLAVERYLGDQQLLGIWGCSGKLICTTAVPWNASWSNKSLD
SLWNWFDITKWLWYIKIFIMIVGGLIGLRIVFTVLSIVNRVRQGYSP
GSTMGAASM
TLTVQARLLLSGIVQQQNNLLRAIEAOORMLQLTVWGI
KQLQARVLAVERYLGDQQLLGIWGCSGKLICTTAVPWNASWSNKSLD
SLWNWFDITKWLWYIKIFIMIVGGLIGLRIVFTVLSIVNRVRQGYSP
GSTMGAASM
TLTVQARLLLSGIVQQQNNLLRAIEAQQRMLQLTVWGI
KQLQARVLAVERYLGDQQLLGIWGCSGKLICTTAVPWNASWSNKSLD
SLWNWFDITKWLWYIKIFIMIVGGLIGLRIVFTVLSIVNRVRQGYSP
AGSTMGAASM
TLTVQARLLLSGIVQQQNNLLRAIEAQORMLOLTV
WGIKQLOARVLAVERYLGDQQLLGIWGCSGKLICTTAVPWNASWS
NKSLDRIWNNMTWMEWEREIDNYTSEIYTLIEESQNQQEKNEQEL
AGSTMGAASM
TLTVQARLLLSGIVQQQNNLLRAIEAQQRMLQLTV
WGIKQLQARVLAVERYLGDQQLLGIWGCSGKLICTTAVPWNASWS
NKSLDRIWNNMTWMEWEREIDNYTSEIYTLIEESQNQQEKNEQEL
The diversity of HIV can be addressed by using a consensus (PCT/US2004/030397 and U.S. application Ser. Nos. 10/572,638 and 11/896,934) and/or mosaic (PCT/US2006/032907) gene T cell and B cell vaccine design strategy. Use of these strategies can eliminate much of the inter- and intra-clade diversity of HIV and induce cross clade T and B cell responses to HIV-1 that are superior to wild-type HIV genes (Gaschen et al, Science 296:2354 (2002); Liao et al, Virology 353:268 (2006), Gao et al, J. Virol. 79:1154 (2005), Weaver et al, J. Virol. 80:6754 (2006)). The mosiac gene approach (Fischer et al, Nature Medicine 13(1):100-106 (2007), Epub 2006 Dec. 24; PCT/US2006/032907) uses in silico evolution to design genes that together, when used as an immunogen, provide optimal T cell epitope coverage for inducing anti-HIV T cell responses. Thus, an integral part of the instant HIV vaccine construct is consensus env, gag, pol, nef, and tat genes. Preferred genes include year 2003 group M consensus gene sequences from Los Alamos National Laboratory HIV Sequence Database sequences, or, alternatively, newer consensus gene sequences selected from a transmitted HIV isolate database, such as developed in the Center for HIV AIDS Vaccine Immunology. In addition, use of mosaic HIV genes, such as gag and nef, can be used to broaden the T cell responses to multiple HIV strains. For induction of neutralizing antibodies, Env constructs can be group M consensus year 2001, CON-S, year 2003 CON-T or a newer consensus Env from transmitted HIV strains, for example, in the forms of gp160, gp140C, gp140CF or gp140CFI (Liao et al, Virology 353:268 (2006)) (gp140CFI refers to an HIV-1 envelope design in which the cleavage-site is deleted (C), the fusion-site is deleted (F) and the gp41 immunodominant region is deleted (I), in addition to the deletion of transmembrane and cytoplasmic domains). Alternatively, year 2003 A1 consensus, 2003 Clade C consensus Envs (Tables 2, 3 and 4) can be used for induction of broadly reactive neutralizing antibodies (U.S. application Ser. No. 10/572,638).
160
176
128
137
66
129
157
185
135
44
46
49
53
149
138
76
110
130
449
291
141
1,257
922
881
402
>540
253
484
8,686
20,502
12,427
9,920
11,030
6,194
5,608
15,012
37,634
41,842
16,225
16,511
86
>540
152
112
364
164
362
304
356
293
134
233
24
42
35
36
43
45
720
1224
1046
751
2,029
2,547
1,939
1,699
99
127
86
173
107
150
108
136
241
237
389
251
70
121
128
152
69
78
64
62
33
50
64
97
89
105
69
34
85
85
78
63
43
40
46
34
33
36
149
533
>540
>540
>540
32
42
76
75
>540
>540
>540
>540
112
119
108
113
49
100
87
96
78
58
66
64
57
169
134
137
168
229
98
170
34
36
108
115
83
100
150
2,203
2,095
506
489
1,546
412
1,301
984
1,489
1,888
92
290
128
421
88
106
540
443
449
711
93
148
41
48
37
36
403
168
258
311
55
50
39
150
71
100
106
54
42
31
43
79
165
111
149
105
136
99
125
916
2,760
1,471
2,822
7,426
7,079
5,166
3,917
43,740
43,740
43,740
43,740
46
93
74
60
354
1,021
2,056
1,161
37
60
116
40
35
63
37
36
42
41
50
68
99
100
52
988
430
438
611
1,299
2,899
1,659
4,195
153
>540
54
46
152
315
127
>540
269
121
126
150
130
141
169
79
52
46
58
53
45
66
48
62
80
45
60
230
261
156
229
>540
377
384
496
3,503
6,297
3,916
5,542
80
150
89
108
129
306
180
285
1,196
412
4,856
1,817
116
233
118
109
41
33
74
54
796
296
1,339
423
2,224
170
415
986
31,224
8,186
41,667
13,369
23,619
9,916
22,467
18,639
444
159
916
444
2,195
463
1,456
1,219
40
40
33
58
42
50
55
90
113
67
44
91
69
113
146
51
52
74
81
32
49
75
68
99
100
52
1,339
770
2,442
724
2,195
463
1,486
1,219
176
329
387
378
46
49
104
51
33
1,819
1,408
3,207
1,336
2,003
540
1,724
1,598
84
61
86
43
33
30
58
137
116
204
95
177
111
70
Vectors to be used to administer the HIV-1 genes include DNA for priming (Letvin et al. Science 312:1530-33 (2006)), recombinant adenovirus for boosting (Barouch et al, Nature 441:239-43 (2006), Letvin et al, Science 312:1530-33 (2006), Thorner et al, J. Virol. Epub. Oct. 11, 2006), recombinant vesicular stomatitis virus (Publicover et al, J. Virol. 79:13231-8 (2005)) and recombinant mycobacteria such as attenuated TB, rBCG or rM. smegmatis (Hovav et al, J. Virol., epub., Oct. 18, 2006, Yu et al, Clin. Vacc. Immunol. 13:1204-11 (2006); Derrick et al, Immunology, epub. Oct. 31, 2006). Any of these vectors can be used in prime/boost combinations, and the route of immunization can be systemic (e.g., IM. SC) or mucosal (po. IN, Intravaginally, Intrarectally).
As pointed out above, the present vaccination approach includes a component for overcoming HIV-1 induced apoptosis and immunosuppression to eliminate the delay in T and B cell responses following HIV-1 transmission at mucosal sites. It has recently been shown that while multiple antibody species arise very early in acute HIV infection, non-neutralizing anti-gp41 antibodies arise the earliest, and autologous neutralizing antibodies do not arise until months after transmission (
Fas and FasL are dysregulated in chronic HIV-1 infection (Cossarizza et al, AIDS14:346 (2000); Westendorp et al, Nature 375:497 (1995); Sloand et al, Blood 89:1357 (1997)). Studies have been undertaken to determine if there are elevations in plasma Fas or FasL in acute HIV infection. It has been found that, in many AHI patients, there is a dramatic rise in plasma FasL coincident with the rise in plasma viral load (
TNFR2 levels are increased in chronic HIV and are predictive of disease progression (Zangerle et al. Immunol Lett. 41:229 (1994)) and TNFR2 is triggered at an early stage of interaction of HIV with monocytes (Rimaniol et al, Cytokine 9:9-18 (1997)). As shown in
Finally, TRAIL mediates apoptosis of uninfected T cells during HIV infection (Kasich et al, JEM186:1365 (1997); Miura et al, J. Exp. Med. 193: 51 (2001)).
Thus, HIV virions and HIV envelope can directly induce T cell death in AHI, soluble TRAIL can bind to uninfected cells and induce death in AHI, and with both HIV infection of cells and with massive apoptosis, high levels of phosphatidylserine containing cells and particles likely abound in AHI. It has recently been shown that PD-1 (programmed death molecule-1) is present on the surface of human B cells in chronic HIV infection. This suggests that human B cells are primed for apoptosis in HIV infection (
Phosphatidylserine (PS) on the surface of HIV infected cells and virions has been found (
Thus, the massive apoptosis that occurs with acute HIV infection with resulting release of TRAIL, mediation of apoptosis via FAS-FASL interactions, and release of PS containing viral and other particles all conspire to initially immunosuppress the host, preventing rapid protective B cell responses.
The present invention includes strategies to prevent apoptosis that include, but are not limited to, the use of PS-containing HIV immunogens, such as PS liposomes, either with or without CON-S or CON-T gp140 or HIV env epitopes associated with the liposomes, such as 2F5-GTH1 peptide lipid conjugates (
Other strategies of the invention that can be used to preventapoptosis are inclusion of the HIV tat gene or protein in the HIV vaccine immunogen to induce antibodies against the tat protein that will inhibit the ability of tat to induce apoptosis in immune cells (Eusoli et Microbes Infect. 7:1392-9 (2005)). Forms of tat that can be used include the 101 amino acid tat protein or the gene encoding such a protein (Watkins et al, Retrovirology 3:1742 (2006)).
In addition to the above, a pancaspase inhibitor (e.g., zVAD-FMK (see also Dean et al. Cancer Treat. Rev. 33:203-212 (2007), Meng et al Current. Opinion Cell Biol. 18:668-676 (2006)) can be included in the vaccine to simultaneously inhibit any vaccine or immune cell activation associated with apoptosis to allow antibody responses to occur quickly. Any Env associated immunosuppression would be overcome. A pancaspase inhibitor can also be used to treat chronic HIV infection.
Correction of the immunosuppressive apoptotic insult can also be effected by immunizing with HIV antigens with various inhibitors of TNF such as Etanercept (a dimeric human TNFR p75-FC fusion protein) or with antibodies against TNFα (such as Infliximab or Adalimumab) (see “Rheumatoid Arthritis”, by EW St. Clair, DS Pisetsky and BF Haynes, Lippincott Williams and Wilkins, 2004, particularly chapters 31 and 32.) and an inhibitor of Fas-Fas ligand interactions (like Fas-Fc) and an inhibitor of TRAIL-DR5 interactions (such as DR5-Fc) (these can be used together or separately). Such agents can also be used to treat chronic HIV infection.
The components of the multicomponent vaccine of the invention can be formulated, as appropriate, with a pharmaceutically acceptable carrier using techniques well known in the art. Suitable routes of administration of the vaccine components include, as appropriate, systemic (e.g., intramuscular or subcutaneous), mucosal or intranasal. Optimum dosing regimens can be determined by one skilled in the art and can vary with the patient and specific components used.
Certain aspects of the invention can be described in greater detail in the non-limiting Examples that follows.
The basic components of the multicomponent vaccine are:
1. a strategy to break immune tolerance,
2. an immunogen to overcome diversity and induce broadly reactive neutralizing antibodies,
3. a strategy to evade the immunosuppression associated with massive apoptosis of immune and other cells that occurs at the time of acute HIV infection,
4. a vector/formulation that provides mucosal immune responses.
An example of the invention is the following multicomponent immunogen:
DNA prime containing recombinant CON-S consensus gp160 HIV Env with a ICK cytoplasmic domain motif (break tolerance and deal with diversity, neutralizing antibody responses) recombinant boost with recombinant vesicular stomatitis virus containing CON-S gp140 Env and mosaic gag-nef genes, consensus pol, tat genes (deal with diversity, mucosal immune responses) recombinant CON-S gp140 protein prime and boost in type “B” or “C” oCpGs in a squalene emulsion administered with the DNA and rVSV immunizations (neutralizing antibody responses, break immune tolerance) combined with CD40-ligand and GITRL in a DNA plasmid administered with each immunization.
A Rhesus T Reg cell depletion model has been developed to test the impact of transient T reg inactivation on the host immune response to anthrax protective antigen (rPA). ONTAK (15 mcg/Kg) infused for 5 days into rhesus monkeys significantly reduced (p<0.05) the percent of CD4+/CD25+ cells in peripheral blood (red line vs heavy black;
To test the hypothesis that ONTAK would improve the host immune response to a biodefense immunogen, juvenile Chinese rhesus monkeys were immunized with rPA (protective antigen; 25 μg) alone or in combination with 5 consecutive days of ONTAK (15 mcg/kg IV) infusion. Animals (n=3/group) were bleed for CBC/diff, immunophenotype, chemistry panel, plasma and serum on days—7, 5, 10, 12, 19, 33, 40 post immunization. Shown in
Two measures were used to assess the magnitude and quality of the primary humoral response to PA in the NHP model +/−ONTAK. First, antigen-specific Ig isotype binding was studied and second, a determination was made of the ability of sera to neutralize anthrax toxin (PA+LF) in a TNA assay. The dose of PA (25 μg+Alum) used induced a anti-PA humoral response starting on day 19, as indicated by the geometric mean endpoint titer plotted on a log scale (
An anthrax toxin Neutralization Assay (TNA) has been established for use with mouse and rhesus serum. Test sera were run as a dilution series in the assay. Shown in
Seroconversion panels (HIV-1+/HCV-/HBV-, n=30, HIV-1-/HCV-/HBV+, n=10, and HIV-1-, HCV+/HCV-, n=10) were obtained from ZeptoMetrix Corporation, (Buffalo, N.Y.). Each panel consisted of sequential aliquots of plasma (range 4-30) collected approximately every 3 days from a plasma donor. HIV-1-/HCV-/HBV-human plasmas (n=25) were obtained from Innovative Research, (Southfield, Mich.). All studies were approved by the Duke University human subjects institutional review board.
Viral load testing of the plasma samples was performed by Quest Diagnostics (Lyndhurst, N.J.) RNA PCR Ultra). HCV and HBV viral loads were preformed by Zeptometrix: select HCV viral loads were provided by Philip Norris, Blood Systems Research Institute. San Francisco, Calif.
ELISAs for Fas, Fas Ligand, TRAIL (Diaclone, Besancon Cedex, France), and TNFR2 (Hycult Biotechnology, Uden, The Netherlands) were performed according to the manufacturer's directions. Plasma was assayed undiluted (TRAIL), diluted 1:10 (TNFR2) or diluted 1:2 (Fas Ligand).
The number of MP in each plasma sample was determined with flow cytometry. All flow cytometry analyses were performed on the LSRII Flow Cytometer (BD Biosciences, San Jose, Calif.) and data analyses were performed using FlowJo software (Ashland, Oreg.). All buffers (PBS without calcium and magnesium) (Cellgro, Herndon, Va.) and formaldehyde (Sigma, St. Louis, Mo.) were filtered with a 0.22 am filter (Millipore, Billerica, Mass.) before use in any MP experiment. The buffer used to dilute plasma samples (1% formaldehyde in PBS without calcium and magnesium) was used to define the background MP count (˜1500 events counted in 60 seconds on the flow cytometer). To define the MP gate, FluoSpheres Fluorescent Microspheres (Molecular Probes, Eugene, Oreg.), ranging in size from 0.1 μm to 1 μm, were analyzed on the flow cytometer. The MP gate was drawn around the beads, encompassing the 0.1 μm, 0.2 μm, 0.5 μm, and 1.0 μm beads. Each plasma sample was diluted 1:100 and 1:1000 in 1% formaldehyde/PBS, and data acquired for 60 seconds. Optimal sample dilutions were determined experimentally, with the acceptance criteria being the dilution of plasma with abort counts <5%, and noise to signal ratios <0.1 (noise to signal ratio=background MP count in PBS/experimental plasma MP count) (
Plasma samples (2 ml) were diluted in 5 ml of filtered saline and then filtered through a 5 μm filter (Pall Corporation, East Hills, N.Y.). The diluted samples were then centrifuged (1 hr at 200,000×g at 4° C.) (Sorvall RC M150 GX, Thermo Fisher Scientific, Waltham, Mass.). The top 2.5 ml of supernatant was removed, 2.5 ml of fresh saline added and samples were centrifuged×1 hr, 200,000×g. The pellet was washed ×2 in 1 ml of filtered saline; after the last wash, 900 μl of the supernatant was removed and the pellet resuspended in the remaining 200 μl of saline. Ten μl of MP suspension was incubated with an antibody and/or annexin V (total volume of 100 μl×20 minutes, 20° C., in the dark). Saline with 1% BSA (Sigma) was used as staining buffer for incubation with antibodies, and 2.5 mM CaCl2 added to the buffer for annexin V staining. For annexin V control, 50 mM EDTA was added to the buffer, incubated 20 min., the volume adjusted to 500 μl with saline/formaldehyde, and analyzed by flow cytometry within 24 hours. Conjugated antibodies included mouse anti-human CD45-PE, CD3-PE, CD4-PE, CD6a, CD63, CCR5-PE, CD14-PE, CD19-PE, and isotype controls (BD Biosciences, San Jose, Calif.), and annexin V conjugated to AlexaFluor 647 (Molecular Probes, Eugene, Oreg.).
Eight ml of plasma was diluted 1:5 in filtered saline and MP pelleted (200,000×g×1 hr, 4° C.). Pellets were washed (200,000×g×1 hr, 4° C.). The pellet was resuspended in 1 ml of saline and washed ×2 (100,000×g×30 minutes). The MP pellet was resuspended in 500 μl of saline and overlaid onto 1 ml of a 40% sucrose solution, and MP centrifuged (100,000×g×90 min.). The pellets were fixed (1% formaldehyde, 4° C. overnight), pelleted, (100,00×g×60 min.), soaked in 1% osmium tetroxide×10 min. and rinsed with saline. The pellets were mounted in agar and embedded in epoxy resin and baked overnight at 60° C. Ultrathin sections were cut and stained and were examined with a Philips CM12 transmission electron microscope,
To establish a reference point throughout all the plasma seroconversion panels, Day “0” was defined as the date when viral load reached 100 copies/ml for HIV-1, 600 copies/ml for HCV, and 700 copies/ml for HBV.
To determine the percent increase in plasma markers of apoptosis during HIV-1, HBV, and HCV infections, the mean TRAIL, TNFR2, or Fas Ligand level before Day 0 was compared to the mean level after Day 0, and percent increase was calculated, ([(mean after day 0−mean before day 0)/mean after day 0]×100).
To compare the plasma markers of apoptosis during the course of infection, the mean levels of TRAIL. TNFR2, and Fas Ligand in uninfected donors, in the first sample of the seroconversion panel (first observation), and at the peak of viral load were compared in HIV-1 infection and in HBV and HCV infections (data not shown). Boxplot analyses were then performed for each group of data. Briefly, for each of the three groups compared, the maximum value, the minimum value, the mean value, and the first and third quartiles (encompassed by box) were calculated. Outliers (1.5× the difference between the third quartile and the first quartile of data) were omitted. Using a Students' t test, the means of each group were compared, and P values calculated.
To analyze the timing of the appearance of the plasma markers of apoptosis during HIV-1 infection, metrics were developed to characterize viral expansion rates. Metrics developed included maximum viral expansion rate, (r0), and date of peak for each plasma marker of apoptosis. For these analyses, six subjects of the thirty total were excluded because the associated viral load data was too sparsely sampled to yield reliable metrics. Viral expansion rate (r0) was determined using the two points within viral ramp-up which yield maximum expansion. For purposes of establishing the timing relationships between viral load and analyte metrics, Wilcoxon Rank Sum tests were performed for paired data. Each test performed compared date of maxium viral expansion with the date of a peak metric.
To optimize existing flow cytometric protocols for the investigations of microparticles, variety of experiments were performed. First, dilution series of polystyrene beads were assayed with the LSRII to determine acceptable signal to noise ratios and abort counts (
TRAIL, TNFR2 and Fas Ligand were Elevated in Most Patients Either Just Before or During Viral Load Ramp-Up During Acute HIV-1 Infection.
To compare the viral kinetics, as well as the timing of the plasma markers of apoptosis and microparticle levels of one plasma donor patient to another, a common timepoint (Day 0) was determined for each of 30 HIV-1, 10 HCV and 10 HBV patients (
Next, to determine if changes of plasma markers of apoptosis could be detected at early timepoints in the acute HIV-1 infection process, levels of soluble TRAIL, TNFR2, and Fas Ligand were assayed in all plasma samples of each plasma donor that became HIV-1 viral load positive, and these levels were compared with those seen in HCV and HBV early infections, (
Boxplot analyses were used to determine if analyte levels were significantly different at the time of peak viral load compared to samples drawn from the patient before viral load ramp up. The mean TRAIL, TNFR2, and Fas Ligand levels at the time of peak viral load, compared to the earliest plasma sample drawn from each acute HIV-1 infected patient before Day 0, were significantly different (p<0.01 for TRAIL, p<0.001 for TNRF2 and p<0.001 for Fas Ligand) (
To investigate the timing of peak levels of TRAIL, TNFR2 and Fas Ligand compared to peak viral load, a determination was made of the relationship between the occurrence of an apoptotic analyte peak compared to the peak viral load, and the number of subjects that had peaks in plasma apoptotic analytes occurring before, coincident with or following the peak in HIV-1 viral load (Table 5). The majority of acute HIV-1 infection subjects (30/30 for TRAIL, 27/30 for TNFR2, and 26/30 for Fas Ligand), demonstrated peak analyte levels occurring within a 30-day time frame (i.e., 15 days before, at the time of, or within 15 days after the viral load peak) (Table 5). Of particular interest, the majority of subjects' TRAIL levels (21/30) peaked before the peak viral load, while TNFR2 and Fas Ligand levels more often peaked coincident with viral load (Table 5).
To statistically analyze the timing of peak analyte levels relative to viral kinetics, paired Wilcoxon rank tests were performed (
Because no concomitant peripheral blood mononuclear cell samples were available for the plasma panels, plasma panels were assayed for relative levels of plasma microparticles from ˜10 μM to 1.0 μM in size, and the presence of immune cell and exosome marker were determined on MP. Flow cytometry analyses were used to determine the relative levels of MP, comparing initial versus latency plasma samples from each individual (
All documents and other information sources cited above are hereby incorporated in their entirety by reference.
This application claims priority from U.S. Provisional Application No. 60/859,496. filed Nov. 17, 2006, the entire content of which is incorporated herein by reference.
This invention was made with government support under Grant No. AI0678501 awarded by the National Institutes of Health. The government has certain rights in the invention.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US07/24122 | 11/19/2007 | WO | 00 | 5/21/2010 |
Number | Date | Country | |
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60859496 | Nov 2006 | US |