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OBJECTIVE: Folate receptor alpha (FRα) is overexpressed on >90% of high-grade epithelial ovarian cancers (EOC). Targeting FRα with antibody-drug conjugates has proven utility in the platinum-resistant setting. It is also a potential therapeutic target for immuno-oncologic agents, such as peptide vaccines that work primarily via adaptive and humoral immunity. We tested the hypothesis that FRα peptide immunization could improve outcomes in patients with EOC following response to platinum-based therapy. METHODS: We conducted a randomized, double-blind, multicenter, phase II study to evaluate the safety and efficacy of TPIV200 (a multi-epitope FRα peptide vaccine admixed with GM-CSF) versus GM-CSF alone in 120 women who did not have disease progression after at least 4 cycles of first-line platinum-based therapy. Patients were vaccinated intradermally once every 4 weeks up to 6 times, followed by a boosting period of 6 vaccinations at 12-week intervals. Primary endpoints included safety, tolerability, and progression free survival (PFS). RESULTS: At study termination with a median follow-up of 15.2 months (range 1.2-28.4 months), 68 of 119 intention-to-treat patients had disease progression (55% in TPIV200 + GM-CSF arm and 59% in GM-CSF alone arm). The median PFS was 11.1 months (95% CI 8.3-16.6 months) with no significant difference between the treatment groups (10.9 months with TPIV200 + GM-CSF versus 11.1 months with GM-CSF, HR, 0.85; upper 90% CI 1.17]. No patient experienced a ≥ grade 3 drug-related adverse event. CONCLUSION: TPIV200 was well tolerated but was not associated with improved PFS. Additional studies are required to uncover potential synergies using multiepitope vaccines targeting FRα. Trial Registration NLM/NCBI Registry, NCT02978222, https://clinicaltrials.gov/search?term=NCT02978222.
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Background: The benefits of recombinant interleukin-12 (rIL-12) as a multifunctional cytokine and potential immunotherapy for cancer have been sought for decades based on its efficacy in multiple mouse models. Unexpected toxicity in the first phase 2 study required careful attention to revised dosing strategies. Despite some signs of efficacy since then, most rIL-12 clinical trials have encountered hurdles such as short terminal elimination half-life (T½), limited tumor microenvironment targeting, and substantial systemic toxicity. We developed a strategy to extend the rIL-12 T½ that depends on binding albumin in vivo to target tumor tissue, using single-chain rIL-12 linked to a fully human albumin binding (FHAB) domain (SON-1010). After initiating a dose-escalation trial in patients with cancer (SB101), a randomized, double-blind, placebo-controlled, single-ascending dose (SAD) phase 1 trial in healthy volunteers (SB102) was conducted. Methods: SB102 (NCT05408572) focused on safety, tolerability, pharmacokinetic (PK), and pharmacodynamic (PD) endpoints. SON-1010 at 50-300 ng/kg or placebo administered subcutaneously on day 1 was studied at a ratio of 6:2, starting with two sentinels; participants were followed through day 29. Safety was reviewed after day 22, before enrolling the next cohort. A non-compartmental analysis of PK was performed and correlations with the PD results were explored, along with a comparison of the SON-1010 PK profile in SB101. Results: Participants receiving SON-1010 at 100 ng/kg or higher tolerated the injection but generally experienced more treatment-emergent adverse effects (TEAEs) than those receiving the lowest dose. All TEAEs were transient and no other dose relationship was noted. As expected with rIL-12, initial decreases in neutrophils and lymphocytes returned to baseline by days 9-11. PK analysis showed two-compartment elimination in SB102 with mean T½ of 104 h, compared with one-compartment elimination in SB101, which correlated with prolonged but controlled and dose-related increases in interferon-gamma (IFNγ). There was no evidence of cytokine release syndrome based on minimal participant symptoms and responses observed with other cytokines. Conclusion: SON-1010, a novel presentation for rIL-12, was safe and well-tolerated in healthy volunteers up to 300 ng/kg. Its extended half-life leads to a prolonged but controlled IFNγ response, which may be important for tumor control in patients. Clinical trial registration: https://clinicaltrials.gov/study/NCT05408572, identifier NCT05408572.
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Interleucina-12 , Neoplasias , Animales , Ratones , Humanos , Citocinas , Voluntarios Sanos , Neoplasias/tratamiento farmacológico , Interferón gamma , Interleucina-2 , Proteínas Recombinantes , Albúminas/efectos adversos , Microambiente TumoralRESUMEN
Background: The potential synergy between interleukin-12 (IL-12) and IL-15 holds promise for more effective solid tumor immunotherapy. Nevertheless, previous clinical trials involving therapeutic cytokines have encountered obstacles such as short pharmacokinetics, limited tumor microenvironment (TME) targeting, and substantial systemic toxicity. Methods: To address these challenges, we fused single-chain human IL-12 and native human IL-15 in cis onto a fully human albumin binding (FHAB) domain single-chain antibody fragment (scFv). This novel fusion protein, IL12-FHAB-IL15 (SON-1210), is anticipated to amplify the therapeutic impact of interleukins and combination immunotherapies in human TME. The molecule was studied in vitro and in animal models to assess its pharmacokinetics, potency, functional characteristics, safety, immune response, and efficacy. Results: SON-1210 demonstrated robust binding affinity to albumin and exhibited the anticipated in vitro activity and tumor model efficacy that might be expected based on decades of research on native IL-12 and IL-15. Notably, in the B16F10 melanoma model (a non-immunogenic, relatively "cold" tumor), the murine counterpart of the construct, which had mouse (m) and human (h) cytokine sequences for the respective payloads (mIL12-FHAB-hIL15), outperformed equimolar doses of the co-administered native cytokines in a dose-dependent manner. A single dose caused a marked reduction in tumor growth that was concomitant with increased IFNγ levels; increased Th1, CTL, and activated NK cells; a shift in macrophages from the M2 to M1 phenotype; and a reduction in Treg cells. In addition, a repeat-dose non-human primate (NHP) toxicology study displayed excellent tolerability up to 62.5 µg/kg of SON-1210 administered three times, which was accompanied by the anticipated increases in IFNγ levels. Toxicokinetic analyses showed sustained serum levels of SON-1210, using a sandwich ELISA with anti-IL-15 for capture and biotinylated anti-IL-12 for detection, along with sustained IFNγ levels, indicating prolonged kinetics and biological activity. Conclusion: Collectively, these findings support the suitability of SON-1210 for patient trials in terms of activity, efficacy, and safety, offering a promising opportunity for solid tumor immunotherapy. Linking cytokine payloads to a fully human albumin binding domain provides an indirect opportunity to target the TME using potent cytokines in cis that can redirect the immune response and control tumor growth.
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Interleucina-12 , Melanoma , Humanos , Animales , Ratones , Citocinas , Interleucina-15 , Semivida , Albúmina Sérica Humana , Microambiente TumoralRESUMEN
Preclinical data suggest that a "prime-boost" vaccine regimen using a target-expressing lentiviral vector for priming, followed by a recombinant protein boost, may be effective against cancer; however, this strategy has not been evaluated in a clinical setting. CMB305 is a prime-boost vaccine designed to induce a broad anti-NY-ESO-1 immune response. It is composed of LV305, which is an NY-ESO-1 expressing lentiviral vector, and G305, a recombinant adjuvanted NY-ESO-1 protein. This multicenter phase 1b, first-in-human trial evaluated CMB305 in patients with NY-ESO-1 expressing solid tumors. Safety was examined in a 3 + 3 dose-escalation design, followed by an expansion with CMB305 alone or in a combination with either oral metronomic cyclophosphamide or intratumoral injections of a toll-like receptor agonist (glucopyranosyl lipid A). Of the 79 patients who enrolled, 81.0% had sarcomas, 86.1% had metastatic disease, and 57.0% had progressive disease at study entry. The most common adverse events were fatigue (34.2%), nausea (26.6%), and injection-site pain (24.1%). In patients with soft tissue sarcomas, a disease control rate of 61.9% and an overall survival of 26.2 months (95% CI, 22.1-NA) were observed. CMB305 induced anti-NY-ESO-1 antibody and T-cell responses in 62.9% and 47.4% of patients, respectively. This is the first trial to test a prime-boost vaccine regimen in patients with advanced cancer. This approach is feasible, can be delivered safely, and with evidence of immune response as well as suggestion of clinical benefit.
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Vacunas contra el Cáncer , Sarcoma , Adyuvantes Inmunológicos , Antígenos de Neoplasias/genética , Vacunas contra el Cáncer/efectos adversos , Humanos , Proteínas de la Membrana/genéticaRESUMEN
We conducted an open label, dose escalation Phase 1 clinical trial of a tetravalent dengue DNA vaccine (TVDV) formulated in Vaxfectin® to assess safety and immunogenicity. A total of 40 dengue- and flavivirus-naive volunteers received either low-dose (1 mg) TVDV alone (N = 10, group 1), low-dose TVDV (1 mg) formulated in Vaxfectin (N = 10, group 2), or high-dose TVDV (2 mg, group 3) formulated in Vaxfectin® (N = 20). Subjects were immunized intramuscularly with three doses on a 0-, 30-, 90-day schedule and monitored. Blood samples were obtained after each immunization and various time points thereafter to assess anti-dengue antibody and interferon gamma (IFNγ) T-cell immune responses. The most common adverse events (AEs) across all groups included mild to moderate pain and tenderness at the injection site, which typically resolved within 7 days. Common solicited signs and symptoms included fatigue (42.5%), headache (45%), and myalgias (47.5%). There were no serious AEs related to the vaccine or study procedures. No anti-dengue antibody responses were detected in group 1 subjects who received all three immunizations. There were minimal enzyme-linked immunosorbent assay and neutralizing antibody responses among groups 2 and 3 subjects who completed the immunization schedule. By contrast, IFNγ T-cell responses, regardless of serotype specificity, occurred in 70%, 50%, and 79% of subjects in groups 1, 2, and 3, respectively. The largest IFNγ T-cell responses were among group 3 subjects. We conclude that TVDV was safe and well-tolerated and elicited predominately anti-dengue T-cell IFNγ responses in a dose-related fashion.
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Anticuerpos Neutralizantes/biosíntesis , Anticuerpos Antivirales/biosíntesis , Vacunas contra el Dengue/administración & dosificación , Virus del Dengue/inmunología , Dengue/prevención & control , Inmunidad Celular/efectos de los fármacos , Vacunas de ADN/administración & dosificación , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/química , Adulto , Dengue/inmunología , Dengue/virología , Vacunas contra el Dengue/efectos adversos , Fatiga/etiología , Fatiga/fisiopatología , Femenino , Cefalea/etiología , Cefalea/fisiopatología , Humanos , Esquemas de Inmunización , Inmunogenicidad Vacunal , Inyecciones Intramusculares , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Masculino , Mialgia/etiología , Mialgia/fisiopatología , Seguridad del Paciente , Fosfatidiletanolaminas/administración & dosificación , Fosfatidiletanolaminas/química , Vacunación , Vacunas de ADN/efectos adversosRESUMEN
BACKGROUND: The loss of half the U.S. supply of influenza vaccine due to contamination has created a critical shortage. Dose-sparing strategies that use intradermal delivery of vaccines may be one approach to consider. METHODS: We conducted a randomized, open-label trial outside the influenza season in 100 healthy adults 18 to 40 years of age to compare the immunogenicity and safety of intradermal immunization with influenza vaccine with standard intramuscular immunization. Subjects were randomly assigned to receive either a single intramuscular dose of 0.5 ml of trivalent influenza vaccine, containing at least 15 microg of hemagglutinin per strain, by means of a prefilled syringe or a single intradermal dose of 0.1 ml, containing at least 3 microg of hemagglutinin per strain, by means of a fine-gauge needle; both injections were in the deltoid region. Changes in the hemagglutination-inhibition (HAI) antibody titer were assessed by comparing geometric mean titers and fold increases relative to baseline values and by comparing changes in the seroconversion and seroprotection rates. Local and systemic adverse events were assessed after both types of vaccination. RESULTS: Subjects who received an intradermal injection with one fifth the standard dose of influenza vaccine had increases in the geometric mean HAI titer by a factor of 15.2 for the H1N1 strain in the vaccine, 19.0 for the H3N2 strain, and 12.4 for the B strain on day 21, as compared with respective increases by a factor of 14.9, 7.1, and 15.3 for the intramuscular injection of the standard dose. Seroconversion and seroprotection rates were similar in the two groups on day 21, ranging from 66 to 82 percent and 84 to 100 percent, respectively. Local reactions were significantly more frequent among recipients of intradermal injections than among recipients of intramuscular injections, but such reactions were mild and transient. CONCLUSIONS: In this study of young adults, intradermal administration of one fifth the standard intramuscular dose of an influenza vaccine elicited immunogenicity that was similar to or better than that elicited by intramuscular injection. Intradermal administration could be used to expand the supplies of influenza vaccine, but further studies are needed before this strategy can be recommended for routine use.
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Anticuerpos Antivirales/sangre , Virus de la Influenza A/inmunología , Virus de la Influenza B/inmunología , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Adolescente , Adulto , Femenino , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Humanos , Vacunas contra la Influenza/efectos adversos , Gripe Humana/inmunología , Inyecciones Intradérmicas , Inyecciones Intramusculares , MasculinoRESUMEN
Although there are only four adjuvants used in licensed vaccines for humans, a wealth of information on novel vaccine adjuvants has become available in both animal models and clinical studies over the past decade. Many vaccine candidates require immunopotentiation to achieve a satisfactory immune response, which is driving the search for new and safer approaches. In this review, we take a brief look at what is known of the mechanisms of action, consider some of the elements of product development, then survey several of the classes of adjuvants within the context of human trials.
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Adyuvantes Inmunológicos/administración & dosificación , Vacunas/administración & dosificación , Adyuvantes Inmunológicos/efectos adversos , Animales , Química Farmacéutica , Ensayos Clínicos como Asunto , Humanos , Modelos Animales , Modelos Inmunológicos , Seguridad , Vacunas/efectos adversosRESUMEN
The skin is an attractive target for vaccine delivery. Topical application of adjuvants results in potent immune responses and good safety profiles. Adjuvants can be coadministered in a patch with vaccine antigens (transcutaneous immunization) or similar delivery format, or administered separately with an injection or IS patch (Iomai), leading to enhanced immune responses. These observations have moved into the clinic, highlighting the likelihood that skin delivery of vaccines will play an important future role in vaccine applications.
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Adyuvantes Inmunológicos/administración & dosificación , Piel/inmunología , Vacunas/administración & dosificación , Administración Cutánea , Animales , Cobayas , Humanos , Inmunidad Mucosa , Inmunocompetencia , Células de Langerhans/inmunología , RatonesRESUMEN
The skin provides an attractive immune environment for vaccine delivery and a safe and confined anatomic space for the use of potent adjuvants. It has been presumed that LCs as a class of dendritic cells should stimulate potent immune responses when activated by adjuvants, and this theory is beginning to be validated. Progress on simple pretreatment of the skin has led to well-developed, simple-to-use protocols that are not dissimilar from current protocols used to cleanse the skin before injection. Antigen and adjuvant formulation optimization has progressed, leading to phase 2 testing of the technology in formulated, manufacturable patches. Although delivery optimization and product testing is challenging, the major biologic observations underlying TCI and the IS patch have been established clearly in that large protein antigens have been delivered clinically, resulting in robust immune responses in a safe manner. During the next 5 years, the challenge will be to conduct a development program that leads to safe and effective vaccination in the context of specific applications.
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Inmunidad/inmunología , Inmunización/métodos , Piel/inmunología , Vacunas/administración & dosificación , Administración Cutánea , Animales , HumanosRESUMEN
BACKGROUND: Cytomegalovirus reactivation occurs within 6 months in 60-70% of cytomegalovirus-seropositive patients after allogeneic haemopoietic stem-cell transplantation (HSCT), mainly due to immunosuppression associated with the procedure. Pre-emptive antiviral therapy reduces incidence of cytomegalovirus disease but can be toxic. To reduce the potential for disease and subsequent need for such antiviral drugs, we aimed to assess safety and efficacy of a cytomegalovirus therapeutic DNA vaccine compared with placebo. METHODS: In this exploratory double-blind, placebo-controlled, parallel group, phase 2 trial, up to 80 donor-recipient pairs and 80 unpaired recipients undergoing allogeneic HSCT were planned for enrolment at 16 transplant centres in the USA. Eligible recipients were cytomegalovirus-seropositive, 18-65 years old, without high-risk primary disease, T-cell depletion, previous vaccination for cytomegalovirus, or autoimmune diseases. We randomly allocated participants in both parallel groups in a 1:1 ratio to receive a cytomegalovirus therapeutic DNA vaccine (TransVax; Vical, San Diego, CA, USA) or placebo before conditioning and at 1, 3, and 6 months after transplantation. The vaccine contains plasmids encoding cytomegalovirus glycoprotein B and phosphoprotein 65 formulated with poloxamer CRL1005 and benzalkonium chloride. Randomisation was done by sequential allocation based on Pocock and Simon's method, and stratified by site, donor-recipient HLA matching status, and donor's cytomegalovirus serostatus. The primary outcome was the occurrence rate of clinically significant viraemia resulting in initiation of cytomegalovirus-specific antiviral therapy in the per-protocol assessable population. We assessed rates of adverse events in all participants who received at least one dose of vaccine or placebo. This study is registered with ClinicalTrials.gov, number NCT00285259. FINDINGS: We randomly allocated 108 participants (94 HSCT recipients and 14 paired donors) between June 29, 2006, and Dec 11, 2009. Enrolment of the paired arm was halted in February 2008 for logistical reasons. Safety was assessed in all participants; the efficacy population was restricted to 74 unpaired recipients. Groups were balanced for demographic and clinical variables. 19 (48%) of 40 vaccine recipients required cytomegalovirus-specific antiviral therapy, compared with 21 (62%) of 34 controls (p=0·145). However, during follow-up vaccine significantly reduced the occurrence and recurrence of cytomegalovirus viraemia and improved the time-to-event for viraemia episodes compared with placebo. The vaccine was well-tolerated; only one participant discontinued after an allergic reaction. Incidence of common adverse events after HSCT (eg, graft-versus-host disease or secondary infections) did not differ between groups. INTERPRETATION: We show proof of concept for an immunotherapeutic cytomegalovirus vaccine (TransVax) for clinically significant viraemia in the HSCT setting. The reported safety and efficacy outcomes support further development in a phase 3 trial, notwithstanding a lack of significant reduction in the use of cytomegalovirus-specific antiviral therapy compared with placebo in this phase 2 trial. FUNDING: Vical and US National Institute of Allergy and Infectious Diseases.
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Infecciones por Citomegalovirus/terapia , Vacunas contra Citomegalovirus/administración & dosificación , Citomegalovirus/inmunología , Trasplante de Células Madre Hematopoyéticas/métodos , Vacunas de ADN/administración & dosificación , Adulto , Anciano , Anticuerpos Antivirales/sangre , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/prevención & control , Infecciones por Citomegalovirus/virología , Vacunas contra Citomegalovirus/inmunología , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Vacunas de ADN/inmunología , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/inmunología , Viremia/inmunología , Viremia/terapia , Viremia/virología , Adulto JovenRESUMEN
The feasibility of developing a prophylactic vaccine against SARS was assessed by comparing the immune responses elicited by immunizing mice with a recombinant SARS spike glycoprotein (S-protein) formulated with different adjuvants, given by different routes. In both young and aged mice, an intranasal Protollin-formulated S-protein vaccine elicited high levels of antigen-specific IgG in serum, comparable to those elicited by an intramuscular Alum-adsorbed S-protein vaccine. Serum antibodies were shown to be virus neutralizing. Intranasal immunization of young mice with the Protollin-formulated vaccine elicited significant levels of antigen-specific lung IgA in contrast to mice immunized with the intramuscular vaccine in which no antigen-specific lung IgA was detected. Following live virus challenge of aged mice, no virus was detected in the lungs of intranasally immunized mice, in contrast to intramuscularly immunized mice whose lung virus titers were comparable to those observed in control mice.
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Anticuerpos Antivirales/biosíntesis , Cisteína Endopeptidasas/administración & dosificación , Lipopolisacáridos/administración & dosificación , Pulmón/inmunología , Glicoproteínas de Membrana/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología , Vacunas Sintéticas/administración & dosificación , Proteínas del Envoltorio Viral/inmunología , Vacunas Virales/administración & dosificación , Administración Intranasal , Animales , Cisteína Endopeptidasas/inmunología , Citocinas/biosíntesis , Combinación de Medicamentos , Femenino , Inmunización , Lipopolisacáridos/inmunología , Ratones , Ratones Endogámicos BALB C , Glicoproteína de la Espiga del Coronavirus , Vacunas Sintéticas/inmunología , Vacunas Virales/inmunologíaRESUMEN
The elderly have greater morbidity and mortality due to influenza, and respond poorly to influenza vaccination compared to younger adults. This study was designed to determine if the adjuvant heat-labile enterotoxin from Escherichia coli (LT), administered as an immunostimulant (IS) patch on the skin with influenza vaccination, improves influenza immune responses in the elderly. Three weeks following vaccination, hemagglutination inhibition (HAI) responses in LT IS patch recipients showed improvement over those of elderly receiving vaccine alone, as demonstrated by significance or trends in fold rise [A/Panama (P = 0.004), A/New Caledonia (P = 0.09)], seroconversion [A/New Caledonia (63% versus 40%, P = 0.01), A/Panama (54% versus 36%, P = 0.08)] and seroprotection [26%, 20% and 16% greater for the patch group for A/New Caledonia, A/Panama and B/Shandong strains, respectively]. The data suggest that an LT IS patch may further enhance influenza vaccine immune responses in the elderly.
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Adyuvantes Inmunológicos/administración & dosificación , Anciano , Toxinas Bacterianas/administración & dosificación , Enterotoxinas/administración & dosificación , Proteínas de Escherichia coli/administración & dosificación , Vacunas contra la Influenza/administración & dosificación , Adyuvantes Inmunológicos/efectos adversos , Administración Cutánea , Adolescente , Adulto , Toxinas Bacterianas/efectos adversos , Toxinas Bacterianas/inmunología , Enterotoxinas/efectos adversos , Enterotoxinas/inmunología , Proteínas de Escherichia coli/efectos adversos , Proteínas de Escherichia coli/inmunología , Femenino , Humanos , Vacunas contra la Influenza/efectos adversos , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Masculino , Persona de Mediana EdadRESUMEN
Synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG motifs act as immune adjuvants in mice, boosting the humoral and cellular response to coadministered Ags. CpG ODN that stimulate human PBMC are only weakly active in mice. Thus, alternative animal models are needed to monitor the activity and safety of "human" CpG ODN in vivo. This work demonstrates that rhesus macaques recognize and respond to the same CpG motifs that trigger human immune cells. Coadministering CpG ODN with heat-killed Leishmania vaccine provided significantly increased protection of macaques against cutaneous Leishmania infection. These findings indicate that rhesus macaques provide a useful model for studying the in vivo activity of human CpG motifs, and that ODN expressing these motifs act as strong immune adjuvants.
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Adyuvantes Inmunológicos/farmacología , Leishmania major/inmunología , Leishmaniasis Cutánea/prevención & control , Oligodesoxirribonucleótidos/farmacología , Vacunas Antiprotozoos , Adyuvantes Inmunológicos/efectos adversos , Animales , Anticuerpos Antiprotozoarios/biosíntesis , Antígenos de Protozoos/inmunología , Células Cultivadas , Citocinas/biosíntesis , Femenino , Humanos , Cinética , Leishmaniasis Cutánea/inmunología , Leishmaniasis Cutánea/patología , Leucocitos Mononucleares/inmunología , Activación de Linfocitos , Macaca mulatta , Oligodesoxirribonucleótidos/efectos adversos , Vacunas de Productos InactivadosRESUMEN
Leishmania donovani protozoan parasites, the causative agent of visceral leishmaniasis, establish an infection partly by interfering with cytokine signaling in the host macrophages. Therefore, we investigated the expression of the suppressor of cytokine signaling (SOCS) genes in human macrophages infected with L. donovani. The expression of SOCS3 mRNA was induced transiently after exposure to live or heat-killed parasites, but not purified lipophosphoglycan, while that of other SOCS genes remained unchanged. SOCS3 gene expression was not dependent on phagocytosis or on cytokines released by L. donovani-infected macrophages, such as interleukin-1beta or tumor necrosis factor alpha. In addition, Leishmania used a different signaling pathway(s) than bacterial lipopolysaccharide to induce SOCS3 mRNA, as indicated by the kinetics of induction and sensitivity to polymyxin B inhibition. Finally, phosphorylation of the STAT1 transcription factor was significantly reduced in L. donovani-infected macrophages and required de novo transcription. The induction of SOCS3 provides a potent inhibitory mechanism by which intracellular microorganisms may suppress macrophage activation and interfere with the host immune response.
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Leishmania donovani/patogenicidad , Activación de Macrófagos , Macrófagos/parasitología , Proteínas/metabolismo , Proteínas Represoras , Factores de Transcripción , Animales , Citocinas/metabolismo , Humanos , Interferón gamma/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , Monocitos/parasitología , Proteínas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de CitocinasRESUMEN
Oligodeoxynucleotides containing CpG motifs (CpG ODNs) mimic microbial DNA and activate effectors of the innate immune response, which limits the spread of pathogens and promotes an adaptive immune response. CpG ODNs have been shown to protect mice from infection with intracellular pathogens. Unfortunately, CpG motifs that optimally stimulate humans are only weakly active in mice, mandating the use of nonhuman primates to monitor the activity and safety of "human" CpG ODNs in vivo. This study demonstrates that CpG ODN treatment of rhesus macaques significantly reduces the severity of the lesions caused by a challenge with Leishmania: Leishmania superinfection is common in immunocompromised hosts, particularly those infected with HIV. This study shows that PBMCs from HIV-infected subjects respond to stimulation with CpG ODNs. To determine whether CpG ODNs can protect retrovirus-infected primates, SIV-infected macaques were treated with CpG ODNs and then challenged with Leishmania: Both lesion size and parasite load were significantly reduced in the CpG-treated animals. These findings support the clinical development of CpG ODNs as immunoprotective agents in normal and HIV-infected patients.
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Adyuvantes Inmunológicos/uso terapéutico , Antiprotozoarios/uso terapéutico , Islas de CpG/inmunología , Leishmaniasis Cutánea/inmunología , Leishmaniasis Cutánea/prevención & control , Oligodesoxirribonucleótidos/uso terapéutico , Vacunas Antiprotozoos/uso terapéutico , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Adulto , Animales , Antiprotozoarios/administración & dosificación , Células Cultivadas , Femenino , Infecciones por VIH/inmunología , Humanos , Inyecciones Intradérmicas , Leishmania mexicana/inmunología , Leishmaniasis Cutánea/virología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/virología , Macaca mulatta , Masculino , Oligodesoxirribonucleótidos/administración & dosificación , Vacunas Antiprotozoos/administración & dosificación , Síndrome de Inmunodeficiencia Adquirida del Simio/parasitología , Síndrome de Inmunodeficiencia Adquirida del Simio/terapia , Virus de la Inmunodeficiencia de los Simios/inmunología , Carga ViralRESUMEN
Cutaneous leishmaniasis, a parasitic infection causing ulcerating skin lesions, is an important disease worldwide and urgently requires a vaccine. Animal models that closely mimic human disease are essential for designing preventive vaccines against Leishmania major. We have evaluated both biologic and immunologic parameters of cutaneous L. major infection in nonhuman primates. Naïve rhesus macaques or monkeys previously exposed to L. major were infected with varying doses of L. major metacyclic promastigotes, and lesion size was assessed over a 10-week period. Monkeys previously infected with L. major had much smaller lesions that resolved faster compared with those of naïve monkeys in response to the two higher doses of infection. Moreover, eight of nine naïve monkeys had parasites detected in their lesions during the course of the infection. In addition, the cellular infiltrate within the lesions was qualitatively and quantitatively different in naïve versus previously infected monkeys. Finally, an ELIspot assay determined that the magnitude and kinetics of responses differed between previously infected and naïve monkeys.
Asunto(s)
Modelos Animales de Enfermedad , Leishmania major , Leishmaniasis Cutánea/inmunología , Leishmaniasis Cutánea/fisiopatología , Macaca mulatta , Animales , Inflamación/inmunología , Inflamación/fisiopatología , Interferón gamma/biosíntesis , Leishmania major/inmunología , Leishmania major/patogenicidad , Leishmaniasis Cutánea/parasitología , Leucocitos Mononucleares/inmunología , Piel/inmunología , Piel/parasitología , Piel/patologíaRESUMEN
BACKGROUND: Transcutaneous immunization (TCI) is a needle-free technique that delivers antigens and adjuvants to potent epidermal immune cells. To address critical unmet needs in biodefense against anthrax, we have designed a novel vaccine delivery system using a dry adhesive patch that simplifies administration and improves tolerability of a subunit anthrax vaccine. METHODS: Mice and rabbits were vaccinated with recombinant protective antigen of Bacillus anthracis and the heat-labile toxin of Escherichia coli. Serologic changes, levels of toxin-neutralizing antibodies (TNAs), and pulmonary and nodal responses were monitored in the mice. A lethal aerosolized B. anthracis challenge model was used in A/J mice, to demonstrate efficacy. RESULTS: The level of systemic immunity and protection induced by TCI was comparable to that induced by intramuscular vaccination, and peak immunity could be achieved with only 2 doses. The addition of adjuvant in the patch induced superior TNA levels, compared with injected vaccination. CONCLUSIONS: Anthrax vaccine patches stimulated robust and functional immune responses that protected against lethal challenge. Demonstration of responses in the lung suggests that a mechanism exists for protection against challenge with aerosolized anthrax spores. A formulated, pressure-sensitive, dry adhesive patch, which is stable and can be manufactured in large scale, elicited comparable immunoglobulin G and TNA responses, suggesting that an anthrax vaccine patch is feasible and should advance into clinical evaluation.
Asunto(s)
Vacunas contra el Carbunco/administración & dosificación , Carbunco/prevención & control , Bacillus anthracis/inmunología , Proteínas de Escherichia coli , Vacunación , Adyuvantes Inmunológicos , Administración Cutánea , Animales , Carbunco/inmunología , Vacunas contra el Carbunco/inmunología , Anticuerpos Antibacterianos/análisis , Anticuerpos Antibacterianos/biosíntesis , Anticuerpos Antibacterianos/sangre , Toxinas Bacterianas/administración & dosificación , Toxinas Bacterianas/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta Inmunológica , Enterotoxinas/administración & dosificación , Enterotoxinas/inmunología , Ganglios Linfáticos/inmunología , Ratones , Pruebas de Neutralización , Conejos , Proteínas Recombinantes/inmunología , Factores de Tiempo , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/inmunologíaAsunto(s)
Adyuvantes Inmunológicos , Vacunas , Animales , Ensayos Clínicos como Asunto , Emulsiones , Francia , Salud Global , Humanos , Minerales , Tensoactivos , Organización Mundial de la SaludRESUMEN
A method is described using tuberculin purified protein derivative (PPD) as a model to follow the in vivo cellular immune response. This combines induction of a local response, formation of skin blisters, and staining of the cells appearing in the sterile exudate over time, using standard cytopreparatory and immunoperoxidase techniques. Skin blisters were induced over sites previously injected intradermally with PPD or control saline using suction over a template on the forearm. The cells which appeared in the exudate at 24, 36, 48 and 72 h were collected on small cellulose filters which were divided into several parts. The cells on the filter segments were then stained using a biotin-avidin immunoperoxidase method with a panel of monoclonal antibodies, and with enzyme histochemical techniques. This allowed quantitative estimation over an extended period of total numbers of each cell type responding as a local expression of cellular immunity. The kinetics of an early, non-specific inflammatory response could be distinguished from the later immune response using total cell counts. Maximal cell counts correlated well with PPD induced induration at 48 h, showing an overwhelming predominance of mononuclear cells. Over 72 h, the number of non-specific esterase (NSE) positive cells (macrophage) declined while Leu4 positive cells (T cells) increased. OKT4 positive cells (T helper) outnumbered OKT8 positive cells (T suppressor) as the response developed. This method enables the direct quantitative assessment of cell populations arriving at the site of an immune response using a simple inexpensive technique which is painless, non-invasive and non-scarring.