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1.
Optom Vis Sci ; 97(11): 970-977, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33110023

RESUMO

SIGNIFICANCE: Men earn at least 6.5% more than women in their first full-time jobs as optometrists. For current salaries, the gender wage gap is more than 13%. This study details the gender wage gap that remains after controlling for practice ownership, residency training, and employer-defined full-time work. PURPOSE: The purpose of this study was to measure the gender wage gap by region and practice type for full-time optometrists who did not complete a residency and do not own their practice. METHODS: Participants completed an online survey, providing data for their first and current optometry positions and demographic information. Respondents who reported full-time employment in the United States, not completing a residency, and not owning their practice were selected for further analysis by census region and practice type. In each category, the gender wage gap was calculated. RESULTS: In all regions and practice types, men were paid higher starting salaries than women. For current salaries, men were paid higher in almost all regions and practice types. The wage gap increased from starting salary to current salary, although not in all regions and practice types. CONCLUSIONS: When practice ownership, residency completion, and full-time work are controlled for, there remains a difference in the pay received by men and women in optometry. The salary data presented in this study may help optometrists narrow the wage gap.


Assuntos
Optometria/economia , Salários e Benefícios/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Optometria/estatística & dados numéricos , Fatores Sexuais , Sexismo/economia , Inquéritos e Questionários , Estados Unidos/epidemiologia
2.
J Immunother Cancer ; 8(1)2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32317292

RESUMO

BACKGROUND: To compare the clinical efficacy of New York Esophageal squamous cell carcinoma-1 (NY-ESO-1) vaccine with ISCOMATRIX adjuvant versus ISCOMATRIX alone in a randomized, double-blind phase II study in participants with fully resected melanoma at high risk of recurrence. METHODS: Participants with resected stage IIc, IIIb, IIIc and IV melanoma expressing NY-ESO-1 were randomized to treatment with three doses of NY-ESO-1/ISCOMATRIX or ISCOMATRIX adjuvant administered intramuscularly at 4-week intervals, followed by a further dose at 6 months. Primary endpoint was the proportion free of relapse at 18 months in the intention-to-treat (ITT) population and two per-protocol populations. Secondary endpoints included relapse-free survival (RFS) and overall survival (OS), safety and NY-ESO-1 immunity. RESULTS: The ITT population comprised 110 participants, with 56 randomized to NY-ESO-1/ISCOMATRIX and 54 to ISCOMATRIX alone. No significant toxicities were observed. There were no differences between the study arms in relapses at 18 months or for median time to relapse; 139 vs 176 days (p=0.296), or relapse rate, 27 (48.2%) vs 26 (48.1%) (HR 0.913; 95% CI 0.402 to 2.231), respectively. RFS and OS were similar between the study arms. Vaccine recipients developed strong positive antibody responses to NY-ESO-1 (p≤0.0001) and NY-ESO-1-specific CD4+ and CD8+ responses. Biopsies following relapse did not demonstrate differences in NY-ESO-1 expression between the study populations although an exploratory study demonstrated reduced (NY-ESO-1)+/Human Leukocyte Antigen (HLA) class I+ double-positive cells in biopsies from vaccine recipients performed on relapse in 19 participants. CONCLUSIONS: The vaccine was well tolerated, however, despite inducing antigen-specific immunity, it did not affect survival endpoints. Immune escape through the downregulation of NY-ESO-1 and/or HLA class I molecules on tumor may have contributed to relapse.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vacinas Anticâncer/administração & dosagem , Colesterol/administração & dosagem , Melanoma/terapia , Recidiva Local de Neoplasia/epidemiologia , Fosfolipídeos/administração & dosagem , Saponinas/administração & dosagem , Neoplasias Cutâneas/terapia , Adjuvantes Imunológicos/efeitos adversos , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Biópsia , Vacinas Anticâncer/efeitos adversos , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Quimioterapia Adjuvante/efeitos adversos , Quimioterapia Adjuvante/métodos , Colesterol/efeitos adversos , Procedimentos Cirúrgicos Dermatológicos , Intervalo Livre de Doença , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Seguimentos , Humanos , Imunogenicidade da Vacina , Masculino , Melanoma/diagnóstico , Melanoma/imunologia , Melanoma/mortalidade , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Fosfolipídeos/efeitos adversos , Saponinas/efeitos adversos , Pele/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/mortalidade
3.
Mol Immunol ; 54(3-4): 465-71, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23454162

RESUMO

The tumor antigen NY-ESO-1 is one of the most antigenic cancer-testis antigens, first identified by serologic analysis of a recombinant cDNA expression library (SEREX). NY-ESO-1 is expressed in different types of cancers including melanoma. NY-ESO-1-specific spontaneous humoral and cellular immune responses are detected in a large proportion of patients with advanced NY-ESO-1-expressing cancers. Therefore NY-ESO-1 is a good candidate antigen for immunotherapy. Although cellular immune responses to NY-ESO-1 are well characterized, much less is known about the humoral immune responses. In this study, we finely mapped linear antibody epitopes using sera from melanoma patients and shorter overlapping peptide sets. We have shown that melanoma patients' humoral immune systems responded to NY-ESO-1 differently in each individual with widely differing antibody specificity, intensity and antibody subtypes. This knowledge will help us further understand anti-tumor immunity and may also help us to monitor cancer progress and cancer vaccine efficacy in the future.


Assuntos
Anticorpos Antineoplásicos/imunologia , Antígenos de Neoplasias/imunologia , Epitopos/sangue , Melanoma/imunologia , Proteínas de Membrana/imunologia , Peptídeos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/sangue , Vacinas Anticâncer/imunologia , Mapeamento de Epitopos , Epitopos/imunologia , Feminino , Humanos , Imunidade Humoral/imunologia , Masculino , Melanoma/sangue , Proteínas de Membrana/sangue , Pessoa de Meia-Idade , Proteínas Recombinantes/imunologia
4.
PLoS One ; 7(9): e44707, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22970293

RESUMO

NY-ESO-1 has been a major target of many immunotherapy trials because it is expressed by various cancers and is highly immunogenic. In this study, we have identified a novel HLA-B*1801-restricted CD8(+) T cell epitope, NY-ESO-1(88-96) (LEFYLAMPF) and compared its direct- and cross-presentation to that of the reported NY-ESO-1(157-165) epitope restricted to HLA-A*0201. Although both epitopes were readily cross-presented by DCs exposed to various forms of full-length NY-ESO-1 antigen, remarkably NY-ESO-1(88-96) is much more efficiently cross-presented from the soluble form, than NY-ESO-1(157-165). On the other hand, NY-ESO-1(157-165) is efficiently presented by NY-ESO-1-expressing tumor cells and its presentation was not enhanced by IFN-γ treatment, which induced immunoproteasome as demonstrated by Western blots and functionally a decreased presentation of Melan A(26-35); whereas NY-ESO-1(88-96) was very inefficiently presented by the same tumor cell lines, except for one that expressed high level of immunoproteasome. It was only presented when the tumor cells were first IFN-γ treated, followed by infection with recombinant vaccinia virus encoding NY-ESO-1, which dramatically increased NY-ESO-1 expression. These data indicate that the presentation of NY-ESO-1(88-96) is immunoproteasome dependent. Furthermore, a survey was conducted on multiple samples collected from HLA-B18(+) melanoma patients. Surprisingly, all the detectable responses to NY-ESO-1(88-96) from patients, including those who received NY-ESO-1 ISCOMATRIX™ vaccine were induced spontaneously. Taken together, these results imply that some epitopes can be inefficiently presented by tumor cells although the corresponding CD8(+) T cell responses are efficiently primed in vivo by DCs cross-presenting these epitopes. The potential implications for cancer vaccine strategies are further discussed.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Epitopos/imunologia , Antígeno HLA-B18/imunologia , Western Blotting , Linhagem Celular Tumoral , Humanos , Melanoma/imunologia , Melanoma/patologia
5.
Cancer Immunol Immunother ; 60(11): 1625-37, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21698545

RESUMO

BACKGROUND: NY-ESO-1 protein formulated in ISCOMATRIX™ results in CD4+, CD8+ T cell and antibody-mediated immunity. We evaluated persistence of immunity, relapse-free survival and tumour antigen expression upon relapse in patients vaccinated in an earlier trial. METHODS: Immunity was measured in 28 patients with resected NY-ESO-1-expressing tumours (melanoma 25, breast 3) 252-1,155 days (median = 681) after vaccination. In the earlier vaccination, trial patients received NY-ESO-1 with ISCOMATRIX™ adjuvant at three protein doses 10 µg, 30 µg or 100 µg (n = 14); 100 µg NY-ESO-1 protein (n = 8) or placebo (n = 6), together with 1 µg of intradermal (ID) NY-ESO-1 protein twice for DTH skin testing. Immune responses assessed in the current study included antibody titres, circulating NY-ESO-1-specific T cells and DTH reactivity 2 days after DTH skin testing with NY-ESO-1 protein (1 µg) or peptides (10 µg). Relapse-free survival was determined for 42 melanoma patients. On relapse NY-ESO-1 and HLA, class I was assessed by immunohistochemistry in 17. RESULTS: Persisting anti-NY-ESO-1 immunity was detected in 10/14 recipients who had previously received vaccine with ISCOMATRIX™ adjuvant. In contrast, immunity only persisted in 3/14 who received 100 µg un-adjuvanted NY-ESO-1 protein (3/8) or 2 µg DTH protein (0/6) P = 0.02. Hence, persisting NY-ESO-1 immunity was associated with prior adjuvant. Tumour NY-ESO-1 or HLA class I was downregulated in participants who relapsed suggesting immunoediting had occurred. CONCLUSION: Immunoediting suggests that a signal of anti-tumour activity was observed in high-risk resected melanoma patients vaccinated with NY-ESO-1/ISCOMATRIX™. This was associated with measurable persisting immunity in the majority of vaccinated subjects tested. A prospective randomised trial has been undertaken to confirm these results.


Assuntos
Antígenos de Neoplasias/administração & dosagem , Neoplasias da Mama/terapia , Vacinas Anticâncer/administração & dosagem , Colesterol/administração & dosagem , Melanoma/terapia , Proteínas de Membrana/administração & dosagem , Fosfolipídeos/administração & dosagem , Saponinas/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Adulto , Idoso , Sequência de Aminoácidos , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/imunologia , Neoplasias da Mama/imunologia , Vacinas Anticâncer/imunologia , Colesterol/imunologia , Intervalo Livre de Doença , Regulação para Baixo , Combinação de Medicamentos , Hipersensibilidade a Drogas/etiologia , Hipersensibilidade a Drogas/imunologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanoma/imunologia , Proteínas de Membrana/biossíntese , Proteínas de Membrana/imunologia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fosfolipídeos/imunologia , Estudos Prospectivos , Saponinas/imunologia , Pele/imunologia
6.
Free Radic Biol Med ; 51(6): 1116-25, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21586323

RESUMO

In recent years, reactive oxygen species (ROS) derived from the vascular isoforms of NADPH oxidase, Nox1, Nox2, and Nox4, have been implicated in many cardiovascular pathologies. As a result, the selective inhibition of these isoforms is an area of intense current investigation. In this study, we postulated that Nox2ds, a peptidic inhibitor that mimics a sequence in the cytosolic B-loop of Nox2, would inhibit ROS production by the Nox2-, but not the Nox1- and Nox4-oxidase systems. To test our hypothesis, the inhibitory activity of Nox2ds was assessed in cell-free assays using reconstituted systems expressing the Nox2-, canonical or hybrid Nox1-, or Nox4-oxidase. Our findings demonstrate that Nox2ds, but not its scrambled control, potently inhibited superoxide (O(2)(•-)) production in the Nox2 cell-free system, as assessed by the cytochrome c assay. Electron paramagnetic resonance confirmed that Nox2ds inhibits O(2)(•-) production by Nox2 oxidase. In contrast, Nox2ds did not inhibit ROS production by either Nox1- or Nox4-oxidase. These findings demonstrate that Nox2ds is a selective inhibitor of Nox2-oxidase and support its utility to elucidate the role of Nox2 in organ pathophysiology and its potential as a therapeutic agent.


Assuntos
Glicoproteínas de Membrana/metabolismo , NADPH Oxidases/metabolismo , Fragmentos de Peptídeos/metabolismo , Animais , Antioxidantes/farmacologia , Materiais Biomiméticos/farmacologia , Células COS , Chlorocebus aethiops , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/química , NADPH Oxidase 2 , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Engenharia de Proteínas , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo
7.
Biochemistry ; 50(12): 2013-25, 2011 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21319793

RESUMO

Nox5 belongs to the calcium-regulated subfamily of NADPH oxidases (Nox). Like other calcium-regulated Noxes, Nox5 has an EF-hand-containing calcium-binding domain at its N-terminus, a transmembrane heme-containing region, and a C-terminal dehydrogenase (DH) domain that binds FAD and NADPH. While Nox1-4 require regulatory subunits, including p22phox, Nox5 activity does not depend on any subunits. We found that inactive point mutants and truncated forms of Nox5 (including the naturally expressed splice form, Nox5S) inhibit full-length Nox5, consistent with formation of a dominant negative complex. Oligomerization of full-length Nox5 was demonstrated using co-immunoprecipitation of coexpressed, differentially tagged forms of Nox5 and occurred in a manner independent of calcium ion. Several approaches were used to show that the DH domain mediates oligomerization: Nox5 could be isolated as a multimer when the calcium-binding domain and/or the N-terminal polybasic region (PBR-N) was deleted, but deletion of the DH domain eliminated oligomerization. Further, a chimera containing the transmembrane domain of Ciona intestinalis voltage sensor-containing phosphatase (CiVSP) fused to the Nox5 DH domain formed a co-immunoprecipitating complex with, and functioned as a dominant inhibitor of, full-length Nox5. Radiation inactivation of Nox5 overexpressed in HEK293 cells and endogenously expressed in human aortic smooth muscle cells indicated molecular masses of ∼350 and ∼300 kDa, respectively, consistent with a tetramer being the functionally active unit. Thus, Nox5 forms a catalytically active oligomer in the membrane that is mediated by its dehydrogenase domain. As a result of oligomerization, the short, calcium-independent splice form, Nox5S, may function as an endogenous inhibitor of calcium-stimulated ROS generation by full-length Nox5.


Assuntos
Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , NADPH Oxidases/química , NADPH Oxidases/metabolismo , Multimerização Proteica , Animais , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Células HEK293 , Humanos , Proteínas de Membrana/genética , Dados de Sequência Molecular , Mutagênese , Mutação , NADPH Oxidase 5 , NADPH Oxidases/genética , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo
8.
J Biol Chem ; 285(14): 10281-90, 2010 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-20139414

RESUMO

By targeting redox-sensitive amino acids in signaling proteins, the NADPH oxidase (Nox) family of enzymes link reactive oxygen species to physiological processes. We previously analyzed the sequences of 107 Nox enzymes and identified conserved regions that are predicted to have important functions in Nox structure or activation. One such region is the cytosolic B-loop, which in Nox1-4 contains a conserved polybasic region. Previous studies of Nox2 showed that certain basic residues in the B-loop are important for activity and translocation of p47(phox)/p67(phox), suggesting this region participates in subunit assembly. However, conservation of this region in Nox4, which does not require p47(phox)/p67(phox), suggested an additional role for the B-loop in Nox function. Here, we show by mutation of Nox4 B-loop residues that this region is important for Nox4 activity. Fluorescence polarization detected binding between Nox4 B-loop peptide and dehydrogenase domain (K(d) = 58 +/- 12 nm). This interaction was weakened with Nox4 R96E B-loop corresponding to a mutation that also markedly decreases the activity of holo-Nox4. Truncations of the dehydrogenase domain localize the B-loop-binding site to the N-terminal half of the NADPH-binding subdomain. Similarly, the Nox2 B-loop bound to the Nox2 dehydrogenase domain, and both the Nox2 and Nox4 interactions were dependent on the polybasic region of the B-loop. These data indicate that the B-loop is critical for Nox4 function; we propose that the B-loop, by binding to the dehydrogenase domain, provides the interface between the transmembrane and dehydrogenase domains of Nox enzymes.


Assuntos
Membrana Celular/metabolismo , NADPH Oxidases/química , NADPH Oxidases/metabolismo , Oxirredutases/metabolismo , Sequência de Aminoácidos , Humanos , Isoenzimas , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação/genética , NADPH Oxidase 2 , NADPH Oxidase 4 , NADPH Oxidases/genética , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos
9.
Biochemistry ; 49(11): 2433-42, 2010 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-20163138

RESUMO

NADPH oxidase 4 (Nox4) is constitutively active, while Nox2 requires the cytosolic regulatory subunits p47(phox) and p67(phox) and activated Rac with activation by phorbol 12-myristate 13-acetate (PMA). This study was undertaken to identify the domain on Nox4 that confers constitutive activity. Lysates from Nox4-expressing cells exhibited constitutive NADPH- but not NADH-dependent hydrogen peroxide production with a K(m) for NADPH of 55 +/- 10 microM. The concentration of Nox4 in cell lysates was estimated using Western blotting and allowed calculation of a turnover of approximately 200 mol of H(2)O(2) min(-1) (mol of Nox4)(-1). A chimeric protein (Nox2/4) consisting of the Nox2 transmembrane (TM) domain and the Nox4 dehydrogenase (DH) domain showed H(2)O(2) production in the absence of cytosolic regulatory subunits. In contrast, chimera Nox4/2, consisting of the Nox4 TM and Nox2 DH domains, exhibited PMA-dependent activation that required coexpression of regulatory subunits. Nox DH domains from several Nox isoforms were purified and evaluated for their electron transferase activities. Nox1 DH, Nox2 DH, and Nox5 DH domains exhibited barely detectable activities toward artificial electron acceptors, while the Nox4 DH domain exhibited significant rates of reduction of cytochrome c (160 min(-1), largely superoxide dismutase-independent), ferricyanide (470 min(-1)), and other electron acceptors (artificial dyes and cytochrome b(5)). Rates were similar to those observed for H(2)O(2) production by the Nox4 holoenzyme in cell lysates. The activity required added FAD and was seen with NADPH but not NADH. These results indicate that the Nox4 DH domain exists in an intrinsically activated state and that electron transfer from NADPH to FAD is likely to be rate-limiting in the NADPH-dependent reduction of oxygen by holo-Nox4.


Assuntos
NADPH Oxidases/química , NADPH Oxidases/metabolismo , NADP/metabolismo , Oxirredutases/metabolismo , Transferases/metabolismo , Extratos Celulares , Linhagem Celular , Membrana Celular/metabolismo , Citosol/metabolismo , Transporte de Elétrons , Flavina-Adenina Dinucleotídeo/metabolismo , Holoenzimas/química , Holoenzimas/metabolismo , Humanos , Cinética , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , NADPH Oxidase 2 , NADPH Oxidase 4 , NADPH Oxidases/genética , NADPH Oxidases/isolamento & purificação , Oxirredutases/química , Dobramento de Proteína , Estrutura Terciária de Proteína , Transporte Proteico , Espécies Reativas de Oxigênio/metabolismo , Homologia de Sequência de Aminoácidos , Solubilidade , Especificidade por Substrato , Transferases/química
10.
Clin Cancer Res ; 15(7): 2507-13, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19318477

RESUMO

PURPOSE: Ipilimumab is a monoclonal antibody that blocks the immune-inhibitory interaction between CTL antigen 4 (CTLA-4) and its ligands on T cells. Clinical trials in cancer patients with ipilimumab have shown promising antitumor activity, particularly in patients with advanced melanoma. Often, tumor regressions in these patients are correlated with immune-related side effects such as dermatitis, enterocolitis, and hypophysitis. Although these reactions are believed to be immune-mediated, the antigenic targets for the cellular or humoral immune response are not known. EXPERIMENTAL DESIGN: We enrolled patients with advanced melanoma in a phase II study with ipilimumab. One of these patients experienced a complete remission of his tumor. The specificity and functional properties of CD8-positive T cells in his peripheral blood, in regressing tumor tissue, and at the site of an immune-mediated skin rash were investigated. RESULTS: Regressing tumor tissue was infiltrated with CD8-positive T cells, a high proportion of which were specific for Melan-A. The skin rash was similarly infiltrated with Melan-A-specific CD8-positive T cells, and a dramatic (>30-fold) increase in Melan-A-specific CD8-positive T cells was apparent in peripheral blood. These cells had an effector phenotype and lysed Melan-A-expressing tumor cells. CONCLUSIONS: Our results show that Melan-A may be a major target for both the autoimmune and antitumor reactions in patients treated with anti-CTLA-4, and describe for the first time the antigen specificity of CD8-positive T cells that mediate tumor rejection in a patient undergoing treatment with an anti-CTLA-4 antibody. These findings may allow a better integration of ipilimumab into other forms of immunotherapy.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos de Neoplasias/imunologia , Antineoplásicos/uso terapêutico , Melanoma/tratamento farmacológico , Proteínas de Neoplasias/imunologia , Neoplasias Cutâneas/tratamento farmacológico , Linfócitos T Citotóxicos/imunologia , Autoimunidade , Citotoxicidade Imunológica , Método Duplo-Cego , Exantema/induzido quimicamente , Exantema/imunologia , Humanos , Ipilimumab , Linfócitos do Interstício Tumoral/imunologia , Antígeno MART-1 , Melanoma/diagnóstico por imagem , Melanoma/imunologia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/imunologia , Tomografia Computadorizada por Raios X
11.
Cancer Res ; 69(3): 1046-54, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19176376

RESUMO

The tumor antigen NY-ESO-1 is a promising cancer vaccine target. We describe here a novel HLA-B7-restricted NY-ESO-1 epitope, encompassing amino acids 60-72 (APRGPHGGAASGL), which is naturally presented by melanoma cells. The tumor epitope bound to HLA-B7 by bulging outward from the peptide-binding cleft. This bulged epitope was not an impediment to T-cell recognition, however, because four of six HLA-B7(+) melanoma patients vaccinated with NY-ESO-1 ISCOMATRIX vaccine generated a potent T-cell response to this determinant. Moreover, the response to this epitope was immunodominant in three of these patients and, unlike the T-cell responses to bulged HLA class I viral epitopes, the responding T cells possessed a remarkably broad TCR repertoire. Interestingly, HLA-B7(+) melanoma patients who did not receive the NY-ESO-1 ISCOMATRIX vaccine rarely generated a spontaneous T-cell response to this cryptic epitope, suggesting a lack of priming of such T cells in the natural anti-NY-ESO-1 response, which may be corrected by vaccination. Together, our results reveal several surprising aspects of antitumor immunity and have implications for cancer vaccine design.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Epitopos Imunodominantes/imunologia , Melanoma/imunologia , Proteínas de Membrana/imunologia , Fragmentos de Peptídeos/imunologia , Alanina/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Apresentação de Antígeno , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/uso terapêutico , Linhagem Celular Tumoral , Antígenos HLA-B/imunologia , Antígeno HLA-B7 , Humanos , Ativação Linfocitária , Melanoma/terapia , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica
12.
J Immunol Methods ; 340(1): 90-4, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18957296

RESUMO

As more tumor antigens are discovered and as computer-guided T cell epitope prediction programs become more sophisticated, many potential T cell epitopes are synthesized and demonstrated to be antigenic in vitro. However, it is estimated that about 50% of such tumor antigen-specific T cells have not been demonstrated to recognize the naturally presented epitopes due to either technical difficulties, such as T cell cloning which is still challenging for many laboratories; or the predicted T cell epitopes are not generated or not generated in sufficient amounts by the antigen processing machinery. However, to potentially identify clinically relevant vaccine candidate epitopes, it is essential to demonstrate natural antigen presentation. Here we combine the advantages of MHC tetramer and intracellular cytokine staining to sensitively detect natural antigen presentation by tumor cells for epitopes of interest. The novel method does not require T cell cloning or long-term T cell culture. Because the antigen-specific T cells are positively identified, this method is much less influenced by IFNgamma producing cells with unknown specificities and should be widely applicable.


Assuntos
Antígenos de Neoplasias/análise , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/análise , Antígenos de Histocompatibilidade/imunologia , Melanoma/imunologia , Antígenos de Neoplasias/imunologia , Linhagem Celular Tumoral , Citocinas/análise , Citocinas/imunologia , Epitopos de Linfócito T/imunologia , Citometria de Fluxo , Humanos
13.
J Speech Lang Hear Res ; 49(1): 113-26, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16533077

RESUMO

PURPOSE: This study examined the cognitive demands of 2 selection techniques in augmentative and alternative communication (AAC), direct selection, and visual linear scanning, by determining the memory retrieval abilities of typically developing children when presented with fixed communication displays. METHOD: One hundred twenty typical children from kindergarten, 1st, and 3rd grades were randomly assigned to either a direct selection or visual linear scanning group. Memory retrieval was assessed through word span using Picture Communication Symbols (PCSs). Participants were presented various numbers and arrays of PCSs and asked to retrieve them by placing identical graphic symbols on fixed communication displays with grid layouts. RESULTS: The results revealed that participants were able to retrieve more PCSs during direct selection than scanning. Additionally, 3rd-grade children retrieved more PCSs than kindergarten and 1st-grade children. An analysis on the type of errors during retrieval indicated that children were more successful at retrieving the correct PCSs than the designated location of those symbols on fixed communication displays. CONCLUSIONS: AAC practitioners should consider using direct selection over scanning whenever possible and account for anticipatory monitoring and pulses when scanning is used in the service delivery of children with little or no functional speech. Also, researchers should continue to investigate AAC selection techniques in relationship to working memory resources.


Assuntos
Auxiliares de Comunicação para Pessoas com Deficiência , Comunicação , Memória , Análise de Variância , Criança , Formação de Conceito , Feminino , Humanos , Masculino
14.
J Immunol Methods ; 291(1-2): 51-62, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15345304

RESUMO

Many tumor antigenic determinants have been identified and included in cancer clinical trials. Due to low T-cell frequencies even after vaccination, few T-cell responses can be revealed ex vivo without in vitro stimulation. Various expansion protocols have been employed for this purpose and the outcomes tend to be quite variable, partly due to the high complexity involved in the protocols. Here we systematically studied various common culture conditions including sera, cytokines and feeders and describe a reliable "bulk" culture method that is robust, simpler and more economical. We demonstrated that fetal calf serum (FCS) supported T-cell proliferation better than multiple commercially available pooled human AB sera. IL-2 is critical in our cultures, but IL-7, IL-15 and anti-CTLA-4 in combination with IL-2 did not further enhance T-cell expansion. We typically achieve more than a 40-fold expansion within a 10-day culture period for antigen-specific T cells measured by HLA-peptide tetramer before and after culture. This method was not only validated by multiple operators as a standard operating procedure for monitoring T-cell responses but was also successfully used for discovering novel CD8+ and CD4+ T cells specific to previously unknown epitopes from the NY-ESO-1 tumor antigen.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Técnicas de Cultura de Células/métodos , Ensaios Clínicos como Assunto , Neoplasias/imunologia , Animais , Anticorpos/imunologia , Anticorpos/farmacologia , Células Apresentadoras de Antígenos/citologia , Células Apresentadoras de Antígenos/imunologia , Antígenos CD , Antígenos de Diferenciação/imunologia , Antígeno CTLA-4 , Bovinos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Epitopos/química , Epitopos/imunologia , Humanos , Interleucina-15/farmacologia , Interleucina-7/farmacologia , Cinética , Neoplasias/sangue , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Reprodutibilidade dos Testes , Soro
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