MXPA00009831A - Hiv-specific cytotoxic t-cell responses - Google Patents

Abstract

A method of generating an HIV-specific cytotoxic T-cell response in a host involves an initial administration of a T-helper molecule to the host to prime T-helper cells of the immune system of the host and a subsequent administration to the host of a mixture of the T-helper molecule and a T-cell inducing HIV-derived molecule to generate an HIV-specific T-cell response in the host.

Description

RESPONSES OF SPECIFIC CYTOTOXIC CELL FOR HIV FIELD OF THE INVENTION The present invention relates to the field of immunology and, in particular, to the generation of T cell responses specific for HIV in a host.

BACKGROUND OF THE INVENTION The acquired immunodeficiency syndrome (AIDS) is a disease that is the final result of infection with the human immunodeficiency virus (HIV). Currently, there is no effective vaccine that can protect the human population against HIV infection, therefore, there is an urgent need for an HIV vaccine and a protocol to administer it. Previously, HIV-1 particles exhaustively inactivated by chemical treatments, a vaccinia vector encoding the complete envelope protein (gpl.sub.10) of HIV-1 and purified recombinant gpl20, have been evaluated as candidate vaccines against HIV. Although inactivated HIV-1 virus preparations produced a T-cell-mediated Type H-mediated Hypersensitivity (DTH) reaction in humans, and candidates for the recombinant gpl20 and gplβO / vaccinia vaccine induced neutralizing antibodies to the virus, none of these immunogens has shown to be an effective vaccine against HIV in humans. The interest of the inventors in the area of HIV vaccines is to develop synthetic HIV-1 peptide vaccines and to consider that their use, alone or together with other candidate vaccines against HIV-1, can lead to the production of more effective immune responses against HIV-1. The inventors have previously previously described in their US Patents Nos. 5,817,318 (European Patent No. 470,980) and 5,639,854, the teachings of which are incorporated herein by reference, inter alia, the identification and characterization of a T cell epitope of the core protein, p24E, of HIV-1, as well as its use in the construction of synthetic and immunogenic chimeric peptides comprising p24E bound to the amino acid sequences of different B-cell epitopes of an HIV-1 core or envelope protein . This effort has been directed towards the design of HIV vaccines capable of producing cell-mediated immunity (CMI) and protocols for the use of them. In this context, the inventors have focused their interest on the viral protein, Rev, expressed early during the HIV virus life cycle because half of the carboxyl terminus is rich in human cytotoxic T cell (CTL) motifs. Peptides that have been generated by immunization with a properly constructed vaccine containing the Rev protein, can therefore be presented in the context of the class 1 molecules of the Major Histocompatibility Complex (MHC) to induce responses of CTL effector capable of killing infected cells with viruses early to limit the spread of viruses. However, the immunization protocol provided herein is applied to peptides containing T cell epitope derived from other HIV proteins.

SUMMARY OF THE INVENTION According to another aspect of this invention, there is provided a method for generating an HIV-specific cytotoxic T cell (CTL) response in a host, comprising: administering to the host an auxiliary T molecule for priming the helper cells T of the immune system of the host, and subsequently administering to the host a mixture of the auxiliary molecule T and a molecule derived from HIV that induces the T cell, in order to generate a T cell response specific for HIV, in the host. Accordingly, the host immune system, which may be a human host, is primed by any convenient T helper molecule and then the auxiliary T molecule is subsequently mixed with a T cell-inducing molecule. In this way, a response is obtained of T-cell specific for HIV. The auxiliary molecule T can be any of the well known materials that provide this MHC class II auxiliary activity in the immune system, including T-cell epitopes specific for DP, DR, DQ, human, T-cell. The materials used as T-helper molecules in the experiments described herein are a peptide corresponding to a portion of the nucleocapsid antigen of the T cell virus. hepatitis B, identified as CLP-243 (SEQ ID NO: 10). The auxiliary molecule T can be administered with an adjuvant, if desired. The T cell-inducing HIV-derived molecule generally includes a peptide corresponding to a portion of an HIV-1 antigen and containing at least one T-cell epitope. In particular, the peptides may correspond to sequences of the Rev protein of HIV-1, particularly corresponding amino acids 52 to 116 (SEQ ID NO: 9) (Table 2) of Rev (CLP-164) of HIV-1 (LAI). The amino acid sequence of the Rev protein is that of the LAI isolates. The invention includes the use of the corresponding peptide sequences from the Rev proteins of other HIV-1 isolates, including the primary isolates. In the experimentation described herein, the peptide was effective in the protocol described herein when provided in the form of a polypeptide, particularly when the lipid is palmitoyl or cholesterol. Two particular lipopeptides used here are CLP-175 and CLP-176, where the palmitoyl and cholesterol derivatives, respectively, are of CLP-164. Mixtures of the auxiliary molecule T and the HIV-derived molecule that induces the T cell can be administered with a suitable adjuvant. The present invention also provides, in another aspect, some novel peptides derived from the HIV-1 Rev protein. Accordingly, in this aspect of the invention, there is provided a peptide having an amino acid sequence corresponding to amino acids 52 to 116 (SEQ ID NO: 9) of the HIV Rev protein sequence and containing the epitopes of T cell within amino acids 65 to 75 (SEQ ID NO: 3), 78 to 87 (SEQ ID N0: 5) and 102 to 110 (SEQ ID N0: 8) (Table 1). This peptide can be provided in the form of a lipopeptide including CLP-175 or CLP-176. The specific amino acid sequences of the peptide having SEQ ID NO: 9, is that of the LAI isolate of HIV-1. Within the scope of the invention is the corresponding peptide and the corresponding T cell epitope sequences of the Rev protein of other HIV-1 isolates, which include the primary isolates. The advantages of the present invention include: an immunization method for inducing the T cell response in a host immunogenic peptides for use in this method.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates the results of in vitro stabilization experiments of HLA-A2 conducted using certain Rev-derived peptides by FACS (fluorescent antibody cell sorting). The peptide CLP-72 (SEQ ID NO: 8), CLP-182 (SEQ ID NO: 7), CLP-178 (SEQ ID NO: 3) and CLP-177 (SEQ ID NO: 2) are bound to HLA -A2 on cell T2, and are shown by the displacement of the respective fluorescent peaks. Figure 2, comprising the panels A to F, illustrates the immunogenicity of HIV-1 Rev immunogens (LAI) in transgenic A2Kb mice using CLP-175, 176 and 164 (SEQ ID N0: 9), with or without priming with CLP-243 (SEQ ID NO: 10). Figure 3, comprising panels A to X, illustrates the CTL induction specific for Rev of HIV-1 (LAI) in transgenic A2Kb mice employing various protocols as described below.

DETAILED DESCRIPTION OF THE INVENTION The inventors have found that two nanomeric peptides, designated CLP-177 (SEQ ID NO: 2) and CLP-72 (SEQ ID NO: 8), a hexamer designated CLP-178 (SEQ ID NO: 3) and a 12-mer designated CLP-182 (SEQ ID NO: 7) of the HIV-1 Rev protein (LAI) (the amino acid sequence of the respective peptides found in Table 1), could individually bind to the molecules Class 1 of the Human Major Histocompatibility Complex (HLA) bound to the membrane, HLA-A2, and stabilize it, this complex is the predominant HLA class 1 subtype found in the Caucasian race. The inventors also found that a long peptide (SEQ ID NO: 9), which spans amino acid residues 52 to 116 of the Rev protein of HIV-1 (LAI) and were constructed with a single cholesterol or palmitoyl entity attached to its amino - (N-) terminal via a KSS linker, to form lipopeptides, CLP-176 and CLP-175 respectively, is also capable of producing CTL as well as P115 antibody responses in transgenic HLA-A2 mice. Based on the experiments provided herein, a novel immunization protocol is provided to induce HIV-specific cytotoxic T cell response in a host, by initial administration of an auxiliary molecule T to prime the host's immune system, followed by the administration of a mixture of the auxiliary molecule T and a peptide containing the T-cell epitope corresponding to a portion of an HIV antigen . The invention is illustrated herein using, as an auxiliary molecule T, a peptide corresponding to a portion of the nucleocapsid antigen of hepatitis B virus. However, other auxiliary T molecules can be employed, for example those that provide MHC class II adjuvant activity in the immune system. The invention is illustrated herein using, as the peptide containing the HIV T cell epitope, some lipopeptides derived from the Rev protein. However, the HIV T cell epitope that contains the peptides derived from any other HIV proteins , may be used. One model has recently been used to predict human CTL antigenic determinants based on the primary sequence (see references 1 to 3, in this P115 description several references will be made to more fully describe the state of the art to which the invention belongs. The complete bibliographic information of each citation is at the end of the specification, immediately before the claims. The expositions of these references are hereby incorporated by reference in their entirety). It has been proposed that CTL epitopes that are most favored to bind and lodge within the peptide binding slot of the human MHC class 1 molecule, for example HLA-A2, normally have 9 amino acids. However, peptides containing 8 to 13 amino acids capable of interacting with HLA class 1 molecules have also been reported. In most cases, these peptides contain a leucine (L) or methionine (M) at position 2, and either an L or a valine (V) at their carboxy termini. The location of the motifs containing potential CTL of the HIV-1 Rev protein (LAI) has been predicted by the reported peptide-binding motif algorithms. Table 1 shows the amino acid sequences of those predicted peptides (SEQ ID NOS: 1 A 8). The ability of the peptides containing these motifs, to bind and stabilize the membrane bound HLA-A2 molecule, was assessed using the T2 cell line. The cell line is well documented with respect to P1154 its defective TAP transporter function, which causes that the majority of intracellularly generated peptides are unable to transport themselves towards the endoplasmic reticulum to associate with the recently synthesized class 1 HLA molecules, ie HLA-A2 (see references 4, 5) . Most of the HLA-A2 molecules displayed on the surface of T2 cells are, therefore, empty (ie they do not contain peptides) and are unstable. During the interaction with the appropriate exogenously introduced peptides, the stability of the HLA-A2 molecules can be restored. The results of the HLA-A2 stabilization experiments in vi tro that were carried out demonstrated that two nanomers, namely CLP-177 (SEQ ID N0: 2) and CLP-72 (SEQ ID N0: 8); and an 11-mer and a 12-mer represented by the peptides, namely CLP-178 (SEQ ID N0: 3) and CLP-182 (SEQ ID NO: 4), respectively; were able to bind to HLA-A2 in T2 cells. This result is shown in the displacement of the respective fluorescent peaks to the right, due to a higher density of class 1 molecules displayed on the cells, as shown in the accompanying Figure 1. Comparison of the respective fluorescence indices revealed that the potency of the peptides is in the following order: CLP-177 > CLP-72 > CLP-178 > C P-182.

Constructs of the lipidated Rev peptides that were tested are shown in Table 2. The results illustrated in Figure 2 show lipid peptides from Rev 52 to 116 (SEQ ID N0: 9), CLP-175 and CLP-176; as well as its non-lipidated counterparts, CLP-164, which were immunogenic, as determined by the IgG titer, when injected three times at a dose of 100.0 μg into transgenic A2Kb mice (ref 6). High titers of IgG antibodies directed against the peptide of Rev 52 to 116 (CLP-164) were detected in the animals that received CLP-175 formulated with Freund's Incomplete Adjuvant (IFA) or CLP-176 or CLP-164 (Panels A, B and C). Mice tested under different experimental environments, by priming them with a dose of CLP-243 in IFA, followed by a double booster with a mixture of CLP-243 + CLP-175 formulated with IFA, or CLP-243 + CLP-176 or CLP-243 + CLP-164, formulated with IFA, similarly produced high anti-CLP-164 antibody responses (Panels D to F). CLP-243 is a restrained I-Ab peptide which spans amino acid residues 128 to 140 (TPPAYRPPNAPIL; SEQ ID NO: 10) of the nucleocapsid antigen of hepatitis B virus (ref 6). The results of the immunogenicity experiments showed that the lipopeptides, CLP-176 and CLP-175, were CTL inducers, as shown in Figure 3. Transgenic A2Kb mice primed subcutaneously with a dose of peptide I-Ab- restricted, CLP-243 in IFA, and with booster dose P1154 double using the same immunization route with a mixture of priming doses of CLP-243 and 100.0 μg of any of the following: CLP-176 or CLP-175, in IFA, generated effector cells that exterminated Jurkat- A2Kb pulsed with nanometer, CLP-177 (Panels A, B, E, F). The cytotoxic activity of the effectors was specific because the Jurkat A2Kb cells not loaded with CLP-177 were not killed (Panels C, D, G and H). In contrast, transgenic A2Kb animals similarly injected once with the inoculum CLP-243 / IFA, and then twice with CLP-243 plus CLP-164 in IFA, did not produce a specific effector response for CLP-177, significant (Panels I , J, K, L). The results of the immunization experiments showed that priming with the peptide I-Ab-restricted, CLP-243, followed by the reinforcement with a mixture of CLP-243 and CLP-176 or CLP 175, was more effective than immunization with the respective lipopeptide alone, for the induction of the CTL response, as shown in Figure 3. It was found that the splenocytes of transgenic A2Kb mice injected 3 times subcutaneously with a dose of 100.0 μg of CLP-176, or CLP- 175, or CLP-164 (Rev 52-116 non-lipidated) in IFA and when re-stimulated with Jurkat A2Kb cells pulsed with CLP-177 and CLP-175 added exogenously at a concentration of 15.0 μg per ml, did not give rise to the generation of effectors capable of killing the Jurkat cells pulsed with the peptide CLP-177 (Panels M to X).

The results of the in vitro re-stimulation experiments showed that the simultaneous re-stimulation of the specific I-Ab-restricted T helper cells for CLP-243 was achieved by the addition of the CLP-243 peptide and the specific effectors for CLP. -177 were achieved by co-culturing them with the Jurkat A2Kb cells pulsed with CLP-177, requiring increasing the enrichment of the specific effectors for CLP-177 and allowing their detection in the CTL in vi tro assay. The components are administered in a manner compatible with the dosage formulation and in an amount that will be therapeutically effective, immunogenic and protective in the immunization protocol. The amount of material to be administered depends on the subject to be treated, including, for example, the ability of the individual's immune system to synthesize antibodies and to produce a cell-mediated immune response. The precise amounts of the required active ingredients that have to be administered depend on the judgment of the physician. However, suitable dose ranges can be readily determined by one skilled in the art and can be in the order of micrograms to milligrams of the material. The dose may also depend on the route of administration and will vary according to the size of the host. Immunogenicity can be significantly improved if the antigens are co-administered with adjuvants. Adjuvants reinforce the immunogenicity of an antigen, but P1154 are not necessarily immunogenic by themselves. The adjuvants can act by retaining the antigen locally near the site of administration to produce a depot effect that facilitates a sustained and slow release of the antigen to the cells of the immune system. Adjuvants can also attract cells of the immune system to an antigen deposit and stimulate these cells to produce an immune response. Immunostimulatory agents or adjuvants have been used for many years to improve host immune responses to, for example, vaccines. Intrinsic adjuvants, for example lipopolysaccharides, are usually the components of the attenuated or killed bacteria used as vaccines. The extrinsic adjuvants are immunomodulators that typically bind non-covalently to the antigens and are formulated to improve the immune responses of the hosts. Therefore, adjuvants have been identified that improve the immune response against antigens administered parenterally. Some of these adjuvants are toxic, however, and can cause undesirable side effects making them unsuitable for use in human and veterinary vaccines. The efficacy of alum in toxoids is well established and an HbsAg vaccine has contained alum as an adjuvant.

A wide range of extrinsic adjuvants can elicit potent immune responses to antigens. These include alumina phosphate, aluminum hydroxide, QS21, Quil A, derivatives and components thereof, calcium phosphate, calcium hydroxide, zinc hydroxide, a glycolipid analogue, an octodecyl ester of an amino acid, a muramyl dipeptide, polyphosphazene, a lipoprotein, an ISCOM matrix, DC-Chol, DDBA and other bacterial adjuvants and toxins, components and derivatives thereof. The particularly advantageous combination is disclosed in co-pending U.S. Application No. 08 / 258,228, filed June 13, 1994 and 08 / 483,856 filed June 7, 1995, assigned to the assignee hereof and whose disclosure it is incorporated herein by reference (WO 95/34308). Under particular circumstances, adjuvants that induce the Thl response are desirable. The invention will be further illustrated in accordance with the following Examples. The above discussion, in general, describes the present invention. For a more complete understanding of it, reference will be made to the following specific Examples. These Examples are described solely for the purpose of illustrating the invention and are not intended to limit it in any way. Changes in the form and P1154 substitution of equivalents according to the circumstances. Although specific terms are used herein, those terms are intended to be descriptive and in no way intended to be limiting.

EXAMPLES Methods of peptide and polypeptide synthesis, cell cultures, enzyme immunoassays (EIA), CTL assays and other test procedures will not be explicitly described in this document but are widely reported in the scientific literature and remain within of the reach of those with expertise in this field.

Example 1; This Example illustrates the synthesis of peptides and lipopeptides. Solid phase peptide synthesis was performed on an ABl 430A automatic peptide synthesizer according to the manufacturer's standard protocols.

The amino acid sequences of the peptides synthesized are shown in the following Table 1. The lysine residues designated for subsequent lipidation were incorporated into the peptides using Na-t-butyloxycarbonyl-Ne-fluorenylmethoxycarbonyl-lysine (Boc-Lys (Fmoc) -OH) ). Lipid entities were incorporated by manual removal of the side-chain Fmoc protecting group, followed by acylation with the appropriate carboxylic acid, activated with 0-benzotriazol-1-yl-N, N, N ', N' -tetramethyluronium hexafluorophosphate. (HBTU) and diisopropylethylamine in dimethylformamide (DMF). The lipopeptides were excised from the solid support by treatment with liquid hydrofluoric acid in the presence of thiocresol, anisole, and methyl sulfide. The crude products were extracted with trifluoroacetic acid (TFA) and precipitated with diethyl ether. The lipopeptides and the non-lipidated peptides are shown in Table 2.

Example 2; This Example illustrates the method used to demonstrate the binding of HLA-A2 and the modulation of the peptides. The T2 cell line expressing the HLA-A2 molecules was obtained from Dr. Peter Creswell of the Howard Hughes Research Institute of Yale University. The cells were propagated in Iscove's complete medium (Iscove's medium supplemented with bovine serum of 10% thermal inactivation, 120.0 units per ml of G sodium penicillin, 120 μg per ml of streptomycin sulfate and 0.35 mg per ml of L-glutamine. ). The ability of peptides P1154 individual 8 to 13 mer, prepared as described in Example 1 and identified in Table 1, to bind and modulate the stability of A2 molecules on T2 cells was determined using a peptide-induced MHC class 1 assembly assay , which was modified from the protocol described by Yuping Deng et al. (ref 6). In essence, 1 × 10 5 T2 cells were incubated with a specific concentration of the test peptide in 250.0 μl of Iscove serum-free medium (Iscove medium supplemented with 120.0 units per ml of sodium penicillin G, 120.0 μg per ml of streptomycin sulfate and 0.35 mg per ml of L-glutamine) in a sterile Eppendorf tube at 37 ° C overnight. After the cells were incubated on ice for 30 min, before 1.0 ml of Iscove's complete medium supplemented with 5.0 μg per ml of Brefeldin A was added, 12.5 μg per ml of 'anisomycin and 5.0 μg per ml of cyclohexamide were added. Then, the samples were incubated for 3.0 hours in an incubator with C02 at 37 ° C. In the presence of drugs, additional protein synthesis and intracellular administration of HLA-A2 molecules to the cell surface is inhibited and destabilization of the conformation of class 1 molecules bound to the membrane at physiological temperature occurs. The cells were then washed twice with PBA P1154 cooled in ice (a regulator containing 0.9% sodium chloride, 0.5% bovine serum albumin and 0.02% sodium azide). Subsequently, 100.0 μl of PBA containing 5.0 μg of a conformal-sensitive mouse monoclonal antibody specific for HLA-A2, BB7.2 (ref 7) was added to each test sample. The reaction was carried out on ice for 45 min. The cells were then washed three times with PBA cooled on ice. Binding of BB7.2 was then detected by adding 100.0 PBA containing 1.0 μg of fluorescein conjugate and goat anti-mouse Ig (F ') FG (FITC) to each cell sample. After 30 min incubation on ice, the cells were washed twice with PBA and another two times with PBS, pH 7.2. The cells were fixed immediately after washing by adding 100.0 μl of 1.0% paraformaldehyde to the cell pellet. The cells were then gently resuspended and analyzed by FACS normally within three days after the experiments were completed. The fluorescence index, which is an indicator of the increased density of A2 molecules bound to the membrane, was calculated by dividing the average fluorescence of an experimental sample (T2 cells treated with peptide) by the mean fluorescence of the control sample (cells T2 not treated with peptide). The results P115 obtained are established in Figure 1.

Example 3; This Example describes the immunization and booster protocol used to test the immunogenicity of peptides and lipopeptides. Mice with a BIO background that were transgenic for the A2Kb chimeric gene were purchased and licensed from the Scripps Clinic in California, USA. The colony remained in the Service Facilities Animal in Pasteur Merieux Connaught Canada. A first group of mice was injected subcutaneously at the base of the tail with a dose of 100.0 μg of peptide formulated with IFA or lipopeptide emulsified in IFA and then booster doses were given at 30 days and again at 42 a 48 days later, with the same inoculum. A second group of mice was injected subcutaneously at the base of the tail with a dose of 100.0 μg of a CLP-243 formulated with IFA and then boosted with a mixture formulated with IFA of the same dose of the immunogen of priming and 100.0 μg of CLP-175 or CLP-176 or CLP-164. The sera of the experimental animals collected on days 10 or 11 after the final injection were analyzed for IgG antibodies.

P1154 specific for CLP-164 using a standard EIA. the results obtained are shown in Figure 2. The splenocytes of the experimental mice were simultaneously cultivated to enrich them for the CTLs before the assessment of the effector activity, as described below.

Example 4; This Example illustrates an in vitro culture method that is used to enrich CTL effectors and CTL titration. Splenocytes from the experimental A2Kb transgenic mice of Example 3 at 3.0 x 107 were cultured with 1.3 x 10 7 Jurkat cells transfected with A2Kb, pulsed with the CLP 175 or CLP 176 peptides in 15.0 ml of complete medium (RPMI 1640 supplemented with 10.0% of thermally inactivated bovine serum at 56 ° C, 120.0 units per ml of sodium penicillin G, 120.0 μg per ml of streptomycin sulfate and 0.35 mg per ml of L-glutamine) per 25 cm2 in a tissue culture flask. The I-Ab-restricted peptide, CLP-243, was also added at a concentration of 15.0 μg per ml at the start of the culture. The cultures were maintained at 37 ° C in a C02 incubator for 7 days and the responders were then tested against peptide-pulsed A2Kb Jurkat transfectant in a standard CTL assay.

P1154 in vi tro for 4 hours, in the following way. Responders were collected from the 7-day cultures and washed twice with the complete medium. The positive blank was created by incubating 1 x 106 Jurkat A2Kb cells with 100.0 μg of the specified peptide, overnight in an incubator with C02 at 37 ° C. The target cells were then labeled with 51Cr at 250.0 uCi for 1 x 106 cells for 1.5 hours in the presence of 25.0 μg of the same test peptides. After washing twice with complete medium to remove excess 51 Cr, the blanks were incubated at 2.5 x 103 with different numbers of responders for 4 hours in an incubator with C02 at 37 ° C. Half of the supernatant was then removed and the radioactivity counted. The results obtained are shown in Figure 3.

EXHIBITION SUMMARY As a summary of the discussion, this invention provides a novel protocol for achieving a specific CTL response for HIV in a host, including a human host, by an inoculation / reinforcement process using T helper molecules and peptide peptides of the protein HIV, as well as novel peptides and novel lipopeptides. Modifications are possible within the scope of the invention.

P1154 TABLE 1 CTL motifs restricted in HLA-A2 of HIV-1 Rev protein (LAI) PEPTIDE AMINO ACID SEQUENCE SEQ ID NO: 1. CLP-279 DLIKAVRL 11-18 1 2. CLP-177 YLGRSAEPV 65-73 2 3. CLP-178 YLGRSAEPVPL 65-75 3 4. CLP-179 QLPPLERL 78-85 4 . CLP-180 QLPPLERLIL 78-87 5 6. CLP-181 PLQLPPLERL 76-85 6 7. CLP-182 PLQLPPLERLIL 76-87 7 8. CLP-72 ILVESPAVL 102-110 8 TABLE 2 Lipopeptides / HIV-1 Rev 52-116 peptides (LAI) tested Lipopeptide / Construction peptide CLP 175 K [Palmitoyl] SS-RQIHSISERILSTYLGRSAEPVPLQLPPLERLTL- -DCNEDCGTSGTQGVGSPQILVESPAVLESGTKE CLP 176 K [cholesterol] SS-RQIHSISERILSTYLGRSAEPVPLQLPPLERLTL- -DCNEDCGTSGTQGVGSPQILVESPAV ESGTKE CLP 164 STY RQIHSISERI GRSAEPVP Q PP ERLT - -DCNEDCGTSGTQGVGSPQILVESPAVLESGTKE (SEQ ID NO: 9) P1154 REFERENCES Ian A Wilson and David H Fremont. Seminars in Immunology, Vol 5, pp. 75-80, 1993. Kirsten Falk and Olaf Rotzschke. Seminars in Immunology, Vol 5, pp. 81-94, 1993. Víctor H Engelhard. Current Opinion in Immunology, Vol 6, pp 13-23, 1994. Salter R D and Creswell P. EMBO J., Vol 5, pp943, 1986. Townsend A. et al. Nature, Vol 340, pp 443, 1989. Yuping Deng et al. Journal of Immunology, Vol 158, pp 1507-1515, 1997.

Claims (17)

1. CLAIMS; 1. The use of an HIV-derived molecule that induces T cells, in the manufacture of a drug that is used to generate an HIV-specific cytotoxic T cell (CTL) response in a host, by: administering a molecule to the host Auxiliary T for priming the T helper cells of the host immune system, and subsequently administering to the host a mixture of the auxiliary T molecule and an HIV-derived molecule that induces the T cell to generate a T cell response specific for HIV, in the host 2. The use of claim 1, characterized in that the auxiliary molecule T is selected from the T-helper epitopes restricted in HLA class II. 3. The use of claim 2, characterized in that the auxiliary epitopes T are selected from the group consisting of T cell epitopes specific for DP, DR and DQ. 4. The use of claim 2, characterized in that the auxiliary molecule T is CLP-243 (SEQ ID NO: 10). 5. The use according to any of claims 1 to 4, characterized in that the auxiliary molecule T is administered with an adjuvant. P1154 6. The use according to any of claims 1 to 5, characterized in that the HIV-derived molecule that induces the T cell includes a peptide corresponding to a portion of an HIV-1 antigen and containing at least one epitope of T cell. The use of claim 6, characterized in that the peptide corresponds to the sequences of the Rev protein of HIV-1. 8. The use of claim 6, characterized in that the peptide is a lipopeptide. 9. The use of claim 8, characterized in that the lipid is palmitoyl or cholesterol. The use of claim 6, characterized in that the lipopeptide is CLP-175 or CLP-176. The use according to any of claims 6 to 10, characterized in that the mixture is administered with an adjuvant. 12. A peptide having an amino acid corresponding to amino acids 52 to 116 (SEQ ID NO: 9) of the Rev protein sequence of HIV-1 LAI isolate and containing T cell epitopes within amino acids 65 to 75 (SEQ ID NO: 3), 78 to 87 (SEQ ID NO: 5) and 102 to 110 (SEQ ID N0: 8), or having a corresponding amino acid sequence of another HIV-1 isolate. The peptide according to claim 12, in P115 form of a lipopeptide. 14. The peptide according to claim 13, characterized in that the lipid is palmitoyl or cholesterol. 15. The peptide according to claim 13, characterized in that the lipopeptide is CLP-175 or CLP-176. 16. The peptide according to any of claims 12 to 15, which is used as a medicament for generating a cytotoxic response (CTL) specific for HIV, in a host. 17. The use of a peptide according to any of claims 12 to 15, in the manufacture of a medicament that is used to generate a cytotoxic response (CTL) specific for HIV, in a host. P1154