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1.
Clin Infect Dis ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657084

RESUMO

BACKGROUND: Shorter prophylactic vaccine schedules may offer more rapid protection against Ebola in resource-limited settings. METHODS: This randomized, observer-blind, placebo-controlled, phase 2 trial conducted in five sub-Saharan African countries included people without HIV (PWOH, n = 249) and people living with HIV (PLWH, n = 250). Adult participants received one of two accelerated Ebola vaccine regimens (MVA-BN-Filo, Ad26.ZEBOV administered 14 days apart [n = 79] or Ad26.ZEBOV, MVA-BN-Filo administered 28 days apart [n = 322]) or saline/placebo (n = 98). The primary endpoints were safety (adverse events [AEs]) and immunogenicity (Ebola virus [EBOV] glycoprotein-specific binding antibody responses). Binding antibody responders were defined as participants with a > 2.5-fold increase from baseline or the lower limit of quantification if negative at baseline. RESULTS: The mean age was 33.4 years, 52% of participants were female, and among PLWH, the median (interquartile range) CD4+ cell count was 560.0 (418.0-752.0) cells/µL. AEs were generally mild/moderate with no vaccine-related serious AEs or remarkable safety profile differences by HIV status. At 21 days post-dose 2, EBOV glycoprotein-specific binding antibody response rates in vaccine recipients were 99% for the 14-day regimen (geometric mean concentrations [GMCs]: 5168 enzyme-linked immunosorbent assay units (EU)/mL in PWOH; 2509 EU/mL in PLWH), and 98% for the 28-day regimen (GMCs: 6037 EU/mL in PWOH; 2939 EU/mL in PLWH). At 12 months post-dose 2, GMCs in PWOH and PLWH were 635 and 514 EU/mL, respectively, for the 14-day regimen and 331 and 360 EU/mL, respectively, for the 28-day regimen. CONCLUSIONS: Accelerated 14- and 28-day Ebola vaccine regimens were safe and immunogenic in PWOH and PLWH in Africa. TRIAL REGISTRATION: NCT02598388.

2.
Clin Infect Dis ; 76(3): e744-e747, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36031390

RESUMO

We followed 54 infants with in utero HIV after initiating very early antiretroviral treatment. At weeks 24 and 48, ≥80% had CD4 ≥1500 cells/mm3 and CD4% ≥25%. Routine Pneumocystis jirovecii pneumonia prophylaxis in the first year of life may not be necessary for all very early treated infants. CLINICAL TRIALS REGISTRATION: NCT02140255.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Pneumocystis carinii , Pneumonia por Pneumocystis , Humanos , Lactente , Infecções por HIV/tratamento farmacológico , Pneumonia por Pneumocystis/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Contagem de Linfócito CD4
3.
Medicine (Baltimore) ; 101(5): e28686, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35119011

RESUMO

ABSTRACT: Define the clinical presentation of acute human immunodeficiency virus infection (AHI) among men and women from 2 continents to create a clinical scoring algorithm.Comparison of incident sign and symptom between those with and without AHI.At-risk human immunodeficiency virus (HIV) negative men and women in Thailand, Kenya, Tanzania, and Uganda underwent twice-weekly testing for HIV. Newly diagnosed participants were evaluated twice weekly for 21 days after infection.Of the 3345 participants enrolled, 56 African females and 36 biological males from Thailand were diagnosed with AHI. Four hundred fifty-two of their encounters were compared to 18,281 HIV negative encounters. Due to a high degree of heterogeneity among incident symptoms, 2 unique subgroups based upon geography and sex were created. Among Thai males, the signs and symptoms with the greatest odds ratio (OR) between AHI and uninfected participants were nausea (OR 16.0, 95% confidence interval [CI] 3.9-60.2, P < .001) and lymphatic abnormalities (OR 11.8, 95% CI 4.2-49.0, P < .001); and among African females were pain behind the eyes (OR 44.4, 95% CI 12.0-158.0, P < .0001) and fatigue (OR 22.7, 95% CI 11.3-44.3, P < .001). The Thai male scoring algorithm had a 66% sensitivity and 84% specificity while the African female algorithm had a sensitivity of 27% and specificity of 98%.The different incident symptoms during AHI necessitated creating 2 different scoring algorithms that can guide diagnostic testing among a particular sex in the appropriate geographic setting. Further research on risk exposure, sex, and demographic specific models is warranted.


Assuntos
Infecções por HIV , Algoritmos , Estudos de Coortes , Feminino , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Humanos , Quênia/epidemiologia , Masculino , Fatores de Risco , Sensibilidade e Especificidade , Tanzânia/epidemiologia , Tailândia/epidemiologia , Uganda/epidemiologia
4.
J Acquir Immune Defic Syndr ; 89(2): 178-182, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34693933

RESUMO

BACKGROUND: HIV protease inhibitors anti-Plasmodium falciparum activity in adults remains uncertain. METHODS: Adults with HIV CD4+ counts >200 cells/mm3 starting antiretroviral therapy (ART) with P. falciparum subclinical parasitemia (Pf SCP) were randomized 1:1 to (step 1) protease inhibitor lopinavir/ritonavir (LPV/r)-based (arm A) or nonnucleoside reverse transcriptase inhibitor (nNRTI)-based ART (arm B) for 15 days. In step 2, participants received nNRTI-based ART and trimethoprim/sulfamethoxazole prophylaxis for 15 days. P. falciparum SCP clearance was measured by polymerase chain reaction. The Fisher exact test [95% exact confidence interval (CI)] was used to compare proportions of P. falciparum SCP clearance (<10 parasites/µL on 3 occasions within 24 hours) between LPV/r and nNRTI arms at day 15. The Kaplan-Meier method and log-rank test were used to compare time-to-clearance. RESULTS: Fifty-two adults from Kenya, Malawi, and Uganda with a median age = 31 (Q1, Q3: 24-39) years, 33% women, with baseline median CD4+ counts of 324 (259-404) cells/mm3, median HIV-1 RNA viremia of 5.18 log10 copies/mL (4.60-5.71), and median estimated P. falciparum density of 454 parasites/µL (83-2219) enrolled in the study. Forty-nine (94%) participants completed the study. At day 15, there was no statistically significant difference in the proportions of P. falciparum SCP clearance between the LPV/r (23.1% clearance; 6 of the 26) and nNRTI (26.9% clearance; 7 of the 26) arms [between-arm difference 3.9% (95% CI, -21.1% to 28.4%; P = 1.00)]. No significant difference in time-to-clearance was observed between the arms (P = 0.80). CONCLUSIONS: In a small randomized study of adults starting ART with P. falciparum SCP, no statistically significant differences were seen between LPV/r- and nNRTI-based ART in P. falciparum SCP clearance after 15 days of treatment.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Inibidores da Protease de HIV , Adulto , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Humanos , Lopinavir , Masculino , Parasitemia/tratamento farmacológico , Plasmodium falciparum , Inibidores da Transcriptase Reversa/uso terapêutico , Ritonavir
5.
J Virol ; 95(17): e0079721, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34160251

RESUMO

Identifying whether viral features present in acute HIV-1 infection predetermine the development of neutralization breadth is critical to vaccine design. Incorporating such features in vaccine antigens could initiate cross-reactive antibody responses that could sufficiently protect vaccinees from HIV-1 infection despite the uniqueness of each founder virus. To understand the relationship between Env determinants and the development of neutralization breadth, we focused on 197 individuals enrolled in two cohorts in Thailand and East Africa (RV144 and RV217) and followed since their diagnosis in acute or early HIV-1 infection. We analyzed the distribution of variable loop lengths and glycans, as well as the predicted density of the glycan shield, and compared these envelope features to the neutralization breadth data obtained 3 years after infection (n = 121). Our study revealed limited evidence for glycan shield features that associate with the development of neutralization breadth. While the glycan shield tended to be denser in participants who subsequently developed breadth, no significant relationship was found between the size of glycan holes and the development of neutralization breadth. The parallel analysis of 3,000 independent Env sequences showed no evidence of directional evolution of glycan shield features since the beginning of the epidemic. Together, our results highlight that glycan shield features in acute and early HIV-1 infection may not play a role determinant enough to dictate the development of neutralization breadth and instead suggest that the glycan shield's reactive properties that are associated with immune evasion may have a greater impact. IMPORTANCE A major goal of HIV-1 vaccine research is to design vaccine candidates that elicit potent broadly neutralizing antibodies (bNAbs). Different viral features have been associated with the development of bNAbs, including the glycan shield on the surface of the HIV-1 Envelope (Env). Here, we analyzed data from two cohorts of individuals who were followed from early infection to several years after infection spanning multiple HIV-1 subtypes. We compared Env glycan features in HIV-1 sequences obtained in early infection to the potency and breadth of neutralizing antibodies measured 1 to 3 years after infection. We found limited evidence of glycan shield properties that associate with the development of neutralization breadth in these cohorts. These results may have important implications for antigen design in future vaccine strategies and emphasize that HIV-1 vaccines will need to rely on a complex set of properties to elicit neutralization breadth.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/epidemiologia , HIV-1/imunologia , Evasão da Resposta Imune/imunologia , Polissacarídeos/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , África Oriental/epidemiologia , Anticorpos Neutralizantes/sangue , Estudos de Coortes , Epitopos , Glicosilação , Anticorpos Anti-HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Tailândia/epidemiologia
6.
AIDS Res Hum Retroviruses ; 36(7): 583-589, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32295382

RESUMO

Antiretroviral therapy (ART) can impact assays used for cross-sectional HIV incidence testing, causing inaccurate HIV incidence estimates. We evaluated the relationship between the timing of ART initiation and the performance of two serologic HIV incidence assays. We analyzed 302 samples from 55 individuals from the RV217 cohort (Early Capture HIV Cohort Study). Participants were grouped by ART start time: ART started <1 year after infection (N = 9); ART started 1-3 years after infection (N = 12); and never received ART (N = 34). Samples were tested using the Sedia LAg-Avidity and Johns Hopkins modified Bio-Rad-Avidity assays. Results were compared with those from the Johns Hopkins HIV Cohort in which participants initiated ART an average of 10 years after infection (N = 17). Participants on ART were virally suppressed at the time of sample collection. The increase in normalized optical density (ODn) values was an average of 2.15 U/year lower in participants who started ART <1 year after infection than in those who did not start ART. Participants who started ART 1-3 years after infection had a decline in ODn values 0.90 U/year faster compared with those who started ART an average of 10 years after infection. Timing of ART initiation did not significantly impact results obtained with the Bio-Rad-Avidity assay. ART initiation <1 year after HIV infection was associated with persistently low limiting antigen (Lag)-Avidity values; this could lead to overestimation of HIV incidence. LAg-Avidity values declined more rapidly the earlier ART was initiated. Bio-Rad-Avidity values were not impacted by the timing of ART initiation.


Assuntos
Antirretrovirais/uso terapêutico , Estudos Transversais/normas , Infecções por HIV/epidemiologia , Programas de Rastreamento/normas , Adolescente , Adulto , Afinidade de Anticorpos , Estudos de Coortes , Estudos Transversais/estatística & dados numéricos , Feminino , Anticorpos Anti-HIV/sangue , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Humanos , Incidência , Masculino , Programas de Rastreamento/estatística & dados numéricos , Resposta Viral Sustentada , Fatores de Tempo , Pessoas Transgênero , Carga Viral , Adulto Jovem
7.
Lancet ; 395(10231): 1195-1207, 2020 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-32145827

RESUMO

BACKGROUND: Optimal treatment regimens for AIDS-associated Kaposi sarcoma, a frequent contributor to morbidity and mortality among people with HIV, have not been systematically evaluated in low-income and middle-income countries, where the disease is most common. In this study, we aimed to investigate optimal treatment strategies for advanced stage disease in areas of high prevalence and limited resources. METHODS: In this open-label, non-inferiority trial, we enrolled people with HIV and advanced stage AIDS-associated Kaposi sarcoma attending 11 AIDS Clinical Trials Group sites in Brazil, Kenya, Malawi, South Africa, Uganda, and Zimbabwe. Eligible participants were randomly assigned (1:1:1) with a centralised computer system to receive either intravenous bleomycin and vincristine or oral etoposide (the investigational arms), or intravenous paclitaxel (the control arm), together with antiretroviral therapy (ART; combined efavirenz, tenofovir disoproxil fumarate, and emtricitabine). The primary outcome was progression-free survival (PFS) at week 48, using a 15% non-inferiority margin to compare the investigational groups against the active control group. Safety was assessed in all eligible treated study participants. The study was registered with ClinicalTrials.gov, NCT01435018. FINDINGS: 334 participants were enrolled between Oct 1, 2013, and March 8, 2018, when the study was closed early due to inferiority of the bleomycin and vincristine plus ART arm, as per the recommendations of the Data and Safety Monitoring Board (DSMB). The etoposide plus ART arm also closed due to inferiority in March, 2016, following a DSMB recommendation. Week-48 PFS rates were higher in the paclitaxel plus ART arm than in both investigational arms. The absolute differences in PFS were -30% (95% CI -52 to -8) for the comparison of paclitaxel plus ART (week 48 PFS 50%, 32 to 67; n=59) and etoposide plus ART (20%, 6 to 33; n=59), and -20% (-33% to -7%) for the comparison of paclitaxel plus ART (64%, 55 to 73; n=138) and bleomycin and vincristine plus ART (44%, 35 to 53; n=132). Both CIs overlapped the non-inferiority margin. The most common adverse events, in 329 eligible participants who began treatment, were neutropenia (48 [15%]), low serum albumin (33 [10%]), weight loss (29 [9%]), and anaemia (28 [9%]), occurring at similar frequency across treatment arms. INTERPRETATION: Non-inferiority of either investigational intervention was not shown, with paclitaxel plus ART showing superiority to both oral etoposide plus ART and bleomycin and vincristine plus ART, supporting its use in treating advanced AIDS-associated Kaposi sarcoma in resource-limited settings. FUNDING: US National Institute of Allergy and Infectious Diseases and National Cancer Institute, National Institutes of Health.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Antibióticos Antineoplásicos/efeitos adversos , Antineoplásicos Fitogênicos/efeitos adversos , Bleomicina/efeitos adversos , Sarcoma de Kaposi/tratamento farmacológico , Vincristina/efeitos adversos , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Adulto , África , Fármacos Anti-HIV/administração & dosagem , Antibióticos Antineoplásicos/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica , Terapia Antirretroviral de Alta Atividade/métodos , Bleomicina/administração & dosagem , Países em Desenvolvimento , Quimioterapia Combinada , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Masculino , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Intervalo Livre de Progressão , Sarcoma de Kaposi/mortalidade , Vincristina/administração & dosagem
8.
Nat Commun ; 11(1): 272, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937782

RESUMO

Mucosa-associated invariant T (MAIT) cell loss in chronic HIV-1 infection is a significant insult to antimicrobial immune defenses. Here we investigate the response of MAIT cells during acute HIV-1 infection utilizing the RV217 cohort with paired longitudinal pre- and post-infection samples. MAIT cells are activated and expand in blood and mucosa coincident with peak HIV-1 viremia, in a manner associated with emerging microbial translocation. This is followed by a phase with elevated function as viral replication is controlled to a set-point level, and later by their functional decline at the onset of chronic infection. Interestingly, enhanced innate-like pathways and characteristics develop progressively in MAIT cells during infection, in parallel with TCR repertoire alterations. These findings delineate the dynamic MAIT cell response to acute HIV-1 infection, and show how the MAIT compartment initially responds and expands with enhanced function, followed by progressive reprogramming away from TCR-dependent antibacterial responses towards innate-like functionality.


Assuntos
Infecções por HIV/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Viremia/imunologia , Biomarcadores/sangue , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Estudos de Coortes , HIV-1/fisiologia , Humanos , Imunidade Inata/genética , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Ativação Linfocitária , Células T Invariantes Associadas à Mucosa/metabolismo , Células T Invariantes Associadas à Mucosa/microbiologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Transcriptoma
9.
Clin Infect Dis ; 71(3): 652-660, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-31504347

RESUMO

BACKGROUND: Patients living with human immunodeficiency virus (PLWH) with low CD4 counts are at high risk for immune reconstitution inflammatory syndrome (IRIS) and death at antiretroviral therapy (ART) initiation. METHODS: We investigated the clinical impact of IRIS in PLWH and CD4 counts <100 cells/µL starting ART in an international, prospective study in the United States, Thailand, and Kenya. An independent review committee adjudicated IRIS events. We assessed associations between baseline biomarkers, IRIS, immune recovery at week 48, and death by week 48 with Cox models. RESULTS: We enrolled 506 participants (39.3% were women). Median age was 37 years, and CD4 count was 29 cells/µL. Within 6 months of ART, 97 (19.2%) participants developed IRIS and 31 (6.5%) died. Participants with lower hemoglobin at baseline were at higher IRIS risk (hazard ratio [HR], 1.2; P = .004). IRIS was independently associated with increased risk of death after adjustment for known risk factors (HR, 3.2; P = .031). Being female (P = .004) and having a lower body mass index (BMI; P = .003), higher white blood cell count (P = .005), and higher D-dimer levels (P = .044) were also significantly associated with increased risk of death. Decision-tree analysis identified hemoglobin <8.5 g/dL as predictive of IRIS and C-reactive protein (CRP) >106 µg/mL and BMI <15.6 kg/m2 as predictive of death. CONCLUSIONS: For PLWH with severe immunosuppression initiating ART, baseline low BMI and hemoglobin and high CRP and D-dimer levels may be clinically useful predictors of IRIS and death risk.


Assuntos
Infecções por HIV , Síndrome Inflamatória da Reconstituição Imune , Linfopenia , Adulto , Contagem de Linfócito CD4 , Feminino , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Síndrome Inflamatória da Reconstituição Imune/epidemiologia , Incidência , Quênia , Linfopenia/epidemiologia , Masculino , Estudos Prospectivos , Tailândia
10.
J Virol ; 93(14)2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31043532

RESUMO

Acute HIV-1 infection is characterized by high viremia and massive depletion of CD4+ T cells throughout all tissue compartments. During this time the latent viral reservoir is established but the dynamics of memory CD4+ T cell subset development, their infectability and influence on disease progression during acute HIV-1 infection has not been carefully described. We therefore investigated the dynamics of CD4+ T cell memory populations in the RV217 (ECHO) cohort during the acute phase of infection. Interestingly, while we found only small changes in central or effector memory compartments, we observed a profound expansion of stem cell-like memory CD4+ T cells (SCM) (2.7-fold; P < 0.0001). Furthermore, we demonstrated that the HIV-1 integration and replication preferentially take place in highly differentiated CD4+ T cells such as transitional memory (TM) and effector memory (EM) CD4+ T cells, while naive and less mature memory cells prove to be more resistant. Despite the relatively low frequency of productively infected SCM, we suggest that their quiescent phenotype, increased susceptibility to HIV-1 integration compared to naive cells and extensive expansion make them one of the key players in establishment and persistence of the HIV-1 reservoir. Moreover, the expansion of SCM in acute HIV-1 infection was a result of Fas upregulation on the surface of naive CD4+ T cells. Interestingly, the upregulation of Fas receptor and expansion of SCM in acute HIV-1 infection was associated with the early viral set point and disease progression (rho = 0.47, P = 0.02, and rho = 0.42, P = 0.041, respectively). Taken together, our data demonstrate an expansion of SCM during early acute HIV-1 infection which is associated with disease outcome.IMPORTANCE Understanding the immunopathology of acute HIV-1 infection will help to develop eradication strategies. We demonstrate here that a CD4+ T cell memory subset expands during acute HIV-1 infection, which is associated with disease progression.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Memória Imunológica , Células-Tronco/imunologia , Regulação para Cima/imunologia , Doença Aguda , Linfócitos T CD4-Positivos/virologia , Estudos de Coortes , Feminino , Humanos , Masculino , Células-Tronco/virologia , Viremia/imunologia
11.
J Infect Dis ; 216(9): 1080-1090, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-28968759

RESUMO

Background: We report the first-in-human safety and immunogenicity evaluation of PENNVAX-G DNA/modified vaccinia Ankara-Chiang Mai double recombinant (MVA-CMDR) prime-boost human immuonodeficiency virus (HIV) vaccine, with intramuscular DNA delivery by either Biojector 2000 needle-free injection system (Biojector) or CELLECTRA electroporation device. Methods: Healthy, HIV-uninfected adults were randomized to receive 4 mg of PENNVAX-G DNA delivered intramuscularly by Biojector or electroporation at baseline and week 4 followed by intramuscular injection of 108 plaque forming units of MVA-CMDR at weeks 12 and 24. The open-label part A was conducted in the United States, followed by a double-blind, placebo-controlled part B in East Africa. Solicited and unsolicited adverse events were recorded, and immune responses were measured. Results: Eighty-eight of 100 enrolled participants completed all study injections, which were generally safe and well tolerated, with more immediate, but transient, pain in the electroporation group. Cellular responses were observed in 57% of vaccine recipients tested and were CD4 predominant. High rates of binding antibody responses to CRF01_AE antigens, including gp70 V1V2 scaffold, were observed. Neutralizing antibodies were detected in a peripheral blood mononuclear cell assay, and moderate antibody-dependent, cell-mediated cytotoxicity activity was demonstrated. Discussion: The PVG/MVA-CMDR HIV-1 vaccine regimen is safe and immunogenic. Substantial differences in safety or immunogenicity between modes of DNA delivery were not observed. Clinical Trials Registration: NCT01260727.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/imunologia , Anticorpos Anti-HIV/sangue , Infecções por HIV/prevenção & controle , Imunidade Celular/efeitos dos fármacos , Vaccinia virus/imunologia , Adulto , África Oriental , Método Duplo-Cego , Eletroporação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Vacinação
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