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1.
Arthritis Res Ther ; 26(1): 65, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459582

RESUMO

BACKGROUND: Lymphopenia, autoantibodies and activation of the type I interferon (IFN) system are common features in systemic lupus erythematosus (SLE). We speculate whether lymphocyte subset counts are affected by pregnancy and if they relate to autoantibody profiles and/or IFNα protein in SLE pregnancy. METHODS: Repeated blood samples were collected during pregnancy from 80 women with SLE and 51 healthy controls (HC). Late postpartum samples were obtained from 19 of the women with SLE. Counts of CD4 + and CD8 + T cells, B cells and NK cells were measured by flow cytometry. Positivity for anti-nuclear antibodies (ANA) fine specificities (double-stranded DNA [dsDNA], Smith [Sm], ribonucleoprotein [RNP], chromatin, Sjögren's syndrome antigen A [SSA] and B [SSB]) and anti-phospholipid antibodies (cardiolipin [CL] and ß2 glycoprotein I [ß2GPI]) was assessed with multiplexed bead assay. IFNα protein concentration was quantified with Single molecule array (Simoa) immune assay. Clinical data were retrieved from medical records. RESULTS: Women with SLE had lower counts of all lymphocyte subsets compared to HC throughout pregnancy, but counts did not differ during pregnancy compared to postpartum. Principal component analysis revealed that low lymphocyte subset counts differentially related to autoantibody profiles, cluster one (anti-dsDNA/anti-Sm/anti-RNP/anti-Sm/RNP/anti-chromatin), cluster two (anti-SSA/anti-SSB) and cluster three (anti-CL/anti-ß2GPI), IFNα protein levels and disease activity. CD4 + T cell counts were lower in women positive to all ANA fine specificities in cluster one compared to those who were negative, and B cell numbers were lower in women positive for anti-dsDNA and anti-Sm compared to negative women. Moreover, CD4 + T cell and B cell counts were lower in women with moderate/high compared to no/low disease activity, and CD4 + T cell count was lower in IFNα protein positive relative to negative women. Finally, CD4 + T cell count was unrelated to treatment. CONCLUSION: Lymphocyte subset counts are lower in SLE compared to healthy pregnancies, which seems to be a feature of the disease per se and not affected by pregnancy. Our results also indicate that low lymphocyte subset counts relate differentially to autoantibody profiles, IFNα protein levels and disease activity, which could be due to divergent disease pathways.


Assuntos
Lúpus Eritematoso Sistêmico , Linfopenia , T-Linfocitopenia Idiopática CD4-Positiva , Feminino , Humanos , Gravidez , Anticorpos Antinucleares , Autoanticorpos , DNA , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/patologia , T-Linfocitopenia Idiopática CD4-Positiva/etiologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Interferon-alfa
2.
Immunol Lett ; 241: 15-22, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34774916

RESUMO

Tumors with a low level of pre-existing immune cell infiltration respond poorly to immune checkpoint therapies. Oncolytic viruses optimize immunotherapies by modulating the tumor microenvironment and affecting multiple steps in the cancer-immunity cycle, making them an attractive agent for combination strategies. We engineered an HSV-1-based oncolytic virus and investigated its antitumor effects in combination with the marketed PD-1 antibody Keytruda (pembrolizumab) in hPD-1 knock-in mice bearing non-immunogenic B16-F10 melanoma. Our results showed enhanced CD8+ and CD4+ T cell infiltration, IFN-γ secretion and PD-L1 expression in tumors, subsequently leading to the prolonged overall survival of mice. Systemic changes in lymphocyte cell proportions were also observed in the peripheral blood. In summary, these findings provide evidence that oncolytic viruses can be engineered as a potential platform for combination therapies, especially to treat tumors that are poorly responsive to immune checkpoint therapy.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Herpes Simples/imunologia , Herpesvirus Humano 1/fisiologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Linfócitos do Interstício Tumoral/imunologia , Melanoma/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/fisiologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Terapia Combinada , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Humanos , Melanoma/imunologia , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
Stem Cell Reports ; 16(6): 1468-1477, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-33961792

RESUMO

Induced pluripotent stem cells (iPSCs) and cancer cells share cellular similarities and transcriptomic profiles. Here, we show that an iPSC-based cancer vaccine, comprised of autologous iPSCs and CpG, stimulated cytotoxic antitumor CD8+ T cell effector and memory responses, induced cancer-specific humoral immune responses, reduced immunosuppressive CD4+ T regulatory cells, and prevented tumor formation in 75% of pancreatic ductal adenocarcinoma (PDAC) mice. We demonstrate that shared gene expression profiles of "iPSC-cancer signature genes" and others are overexpressed in mouse and human iPSC lines, PDAC cells, and multiple human solid tumor types compared with normal tissues. These results support further studies of iPSC vaccination in PDAC in preclinical and clinical models and in other cancer types that have low mutational burdens.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Carcinoma Ductal Pancreático/imunologia , Células-Tronco Pluripotentes Induzidas/imunologia , Neoplasias Pancreáticas/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Animais , Antineoplásicos/uso terapêutico , Linfócitos T CD8-Positivos/metabolismo , Vacinas Anticâncer/metabolismo , Vacinas Anticâncer/uso terapêutico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/terapia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Memória Imunológica , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Pancreáticas/terapia , T-Linfocitopenia Idiopática CD4-Positiva/metabolismo , Transcriptoma , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Cell Host Microbe ; 29(6): 894-903.e5, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-33989514

RESUMO

Babesia spp. are tick-transmitted intra-erythrocytic protozoan parasites that infect humans and animals, causing a flu-like illness and hemolytic anemia. There is currently no human vaccine available. People most at risk of severe disease are the elderly, immunosuppressed, and asplenic individuals. B. microti and B. divergens are the predominant species affecting humans. Here, we present a whole-parasite Babesia vaccine. To establish proof-of-principle, we employed chemically attenuated B. microti parasitized red blood cells from infected mice. To aid clinical translation, we produced liposomes containing killed parasite material. Vaccination significantly reduces peak parasitemia following challenge. B cells and anti-parasite antibodies do not significantly contribute to vaccine efficacy. Protection is abrogated by the removal of CD4+ T cells or macrophages prior to challenge. Importantly, splenectomized mice are protected by vaccination. To further facilitate translation, we prepared a culture-based liposomal vaccine and demonstrate that this performs as a universal vaccine inducing immunity against different human Babesia species.


Assuntos
Babesia microti/imunologia , Babesiose/imunologia , Babesiose/prevenção & controle , Avaliação Pré-Clínica de Medicamentos , Parasitemia/imunologia , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/uso terapêutico , Animais , Anticorpos Antiprotozoários/sangue , Linfócitos B/imunologia , Babesiose/parasitologia , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Imunidade , Lipossomos/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Parasitemia/terapia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Carrapatos/parasitologia
5.
Allergol. immunopatol ; 49(3): 193-201, mayo 2021. tab, graf
Artigo em Inglês | IBECS | ID: ibc-214281

RESUMO

Background: Measles vaccinations have been suggested to provide immune protection and decreased measles incidence. However, there was a limited study evaluating how the measles vaccine elicits specific immune responses. Objective: This study aimed to evaluate both humoral and cellular immunity to first-dose measles vaccine Edmonston-Zagreb (EZ) in 9-month-old Indonesian infants. Methods: A cohort study was conducted on 9-month-old infants who got the first-dose of measles vaccine EZ. Measles-specific immunoglobulin G (IgG) antibody serum levels were measured using plaque-reduction microneutralization assay. Peripheral blood mononuclear cells were stimulated with a measles-specific peptide to identify a cellular immune response. Quantification of CD4+ and CD8+ T-cells producing interferon-gamma (IFN-ɣ) and interleukin 17-A (IL-17A) were conducted by flow cytometry. Humoral and cellular immune response parameters were analyzed over time. Results: The prevalence of seropositivity rates was 85.8% at 1-month after vaccination and 16.67% at 6-months postvaccination. Measles-specific IgG antibodies increased significantly at 1-month after measles vaccination. However, they decreased significantly 6-months after vaccination. IFN-ɣ and IL-17A secreting T-cells increased significantly at 1-month after measles vaccination. Interestingly, a significant decrease of IFN-ɣ and IL-17A secreting CD4+ T cells was noticed 6-months postvaccination compared to IFN-ɣ and IL-17A secreting CD8+ T cells. Conclusion: Our study suggests that the first-dose measles vaccine on 9-months-old infants seems to induce both humoral and cellular immune responses that decline 6-months after vaccination (AU)


Assuntos
Humanos , Masculino , Feminino , Lactente , Especificidade de Anticorpos , Imunidade Celular , Sarampo/prevenção & controle , Vacina contra Sarampo/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Linfócitos T CD8-Positivos/imunologia , Citometria de Fluxo , Estudos de Coortes , Imunoglobulina G/imunologia , Indonésia
6.
Clin Immunol ; 224: 108664, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33422677

RESUMO

OBJECTIVE: Characterize autoantibodies and autoimmune diseases in a prospective cohort of patients with Idiopathic CD4 Lymphocytopenia (ICL) a rare immunodeficiency characterized by an absolute CD4+ T count of <300 cells/µl in the absence of HIV or HTLV infection. METHODS: Single-Center prospective study of 67 patients conducted over an 11-year period. Rheumatologic evaluation and measurement of autoantibodies were systematically conducted, and flow cytometry of immune cell subsets was performed in a subset of patients. RESULTS: 54% of referred patients had clinical evidence of autoimmunity, with 34% having at least one autoimmune disease, most commonly autoimmune thyroid disease. 19%, had autoantibodies or incomplete features of autoimmune disease. Patients with autoimmune disease had more elevated serum immunoglobulins, and more effector memory T cells than those without autoimmunity. CONCLUSIONS: Evidence of autoimmunity, including autoimmune diseases, is more prevalent in ICL than the general population, and should be considered part of this syndrome.


Assuntos
Autoanticorpos/análise , Doenças Autoimunes/imunologia , Imunofenotipagem/métodos , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Adulto , Idoso , Doenças Autoimunes/complicações , Estudos de Coortes , Doenças Transmissíveis/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , T-Linfocitopenia Idiopática CD4-Positiva/complicações , Adulto Jovem
7.
Immunology ; 162(2): 194-207, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32986852

RESUMO

Class II human leucocyte antigen (HLA) proteins are involved in the immune response by presenting pathogen-derived peptides to CD4+ T lymphocytes. At the molecular level, they are constituted by α/ß-heterodimers on the surface of professional antigen-presenting cells. Here, we report that the acceptor variant (rs8084) in the HLA-DRA gene mediates the transcription of an alternative version of the α-chain lacking 25 amino acids in its extracellular domain. Molecular dynamics simulations suggest this isoform undergoes structural refolding which in turn affects its stability and cellular trafficking. The short HLA-DRA isoform cannot reach the cell surface, although it is still able to bind the corresponding ß-chain. Conversely, it remains entrapped within the endoplasmic reticulum where it is targeted for degradation. Furthermore, we demonstrate that the short isoform can be transported to the cell membrane via interactions with the peptide-binding site of canonical HLA heterodimers. Altogether, our findings indicate that short HLA-DRA functions as a novel intact antigen for class II HLA molecules.


Assuntos
Cadeias alfa de HLA-DR/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Isoformas de Proteínas/imunologia , Adulto , Idoso , Aminoácidos/imunologia , Células Apresentadoras de Antígenos/imunologia , Sítios de Ligação/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Membrana Celular/imunologia , Retículo Endoplasmático/imunologia , Feminino , Células HEK293 , Células HeLa , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Peptídeos/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia
8.
J Exp Med ; 218(4)2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33373442

RESUMO

T cells increase cholesterol biosynthesis upon activation to generate substrates for cellular growth and proliferation. The ubiquitously expressed liver X receptor ß (LXRß) encoded by the Nr1h2 gene is a critical regulator of cholesterol homeostasis in mammalian cells; however, its cell-intrinsic role in T cell biology remains poorly understood. We report that ablation of LXRß in T cells leads to spontaneous T cell activation and T lymphocytopenia. Unexpectedly, analysis of mixed bone marrow chimeric mice revealed a cell-autonomous survival defect that reduced the fitness of LXRß-deficient effector T cells, suggesting that the heightened immune activation in mice harboring LXRß-deficient T cells was due to impaired regulatory T (T reg) cell functionality. Indeed, we found that single-copy deletion of Nr1h2 in T reg cells disrupted activated T reg cell metabolism and fitness and resulted in early-onset fatal autoimmune disease. Our study demonstrated an indispensable requirement for T reg cell-intrinsic LXRß function in immune homeostasis and provides a basis for immunological therapies through targeting of this receptor.


Assuntos
Doenças Autoimunes/imunologia , Homeostase/imunologia , Receptores X do Fígado/fisiologia , Ativação Linfocitária/genética , Linfócitos T Reguladores/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Animais , Doenças Autoimunes/genética , Células Cultivadas , Colesterol/metabolismo , Feminino , Fatores de Transcrição Forkhead/genética , Homeostase/genética , Receptores X do Fígado/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quimera por Radiação/imunologia , Transdução de Sinais/genética , Linfócitos T Reguladores/metabolismo , T-Linfocitopenia Idiopática CD4-Positiva/genética
9.
J Clin Invest ; 130(10): 5326-5337, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32634122

RESUMO

BACKGROUNDIdiopathic CD4 lymphopenia (ICL) is defined by persistently low CD4+ cell counts (<300 cells/µL) in the absence of a causal infection or immune deficiency and can manifest with opportunistic infections. Approximately 30% of ICL patients develop autoimmune disease. The prevalence and breadth of their autoantibodies, however, and their potential contribution to pathogenesis of ICL remain unclear.METHODSWe hybridized 34 and 51 ICL patients' sera to a 9,000-human-proteome array and to a 128-known-autoantigen array, respectively. Using a flow-based method, we characterized the presence of anti-lymphocyte Abs in the whole cohort of 72 patients, as well as the Ab functional capability of inducing Ab-dependent cell-mediated cytotoxicity (ADCC), complement deposition, and complement-dependent cytotoxicity (CDC). We tested ex vivo the activation of the classical complement pathway on ICL CD4+ T cells.RESULTSAll ICL patients had a multitude of autoantibodies mostly directed against private (not shared) targets and unrelated quantitatively or qualitatively to the patients' autoimmune disease status. The targets included lymphocyte intracellular and membrane antigens, confirmed by the detection by flow of IgM and IgG (mostly IgG1 and IgG4) anti-CD4+ cell Abs in 50% of the patients, with half of these cases triggering lysis of CD4+ T cells. We also detected in vivo classical complement activation on CD4+ T cells in 14% of the whole cohort.CONCLUSIONOur data demonstrate that a high prevalence of autoantibodies in ICL, some of which are specific for CD4+ T cells, may contribute to pathogenesis, and may represent a potentially novel therapeutic target.TRIAL REGISTRATIONClinicalTrials.gov NCT00867269.FUNDINGNIAID and National Institute of Arthritis and Musculoskeletal and Skin Diseases of the NIH.


Assuntos
Autoanticorpos/sangue , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Adulto , Idoso , Especificidade de Anticorpos , Citotoxicidade Celular Dependente de Anticorpos , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Estudos de Coortes , Ativação do Complemento , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , T-Linfocitopenia Idiopática CD4-Positiva/sangue , T-Linfocitopenia Idiopática CD4-Positiva/etiologia , Adulto Jovem
10.
Cell Host Microbe ; 28(1): 54-68.e7, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32526160

RESUMO

The Salmonella enterica effector SteD depletes mature MHC class II (mMHCII) molecules from the surface of infected antigen-presenting cells through ubiquitination of the cytoplasmic tail of the mMHCII ß chain. Here, through a genome-wide mutant screen of human antigen-presenting cells, we show that the NEDD4 family HECT E3 ubiquitin ligase WWP2 and a tumor-suppressing transmembrane protein of unknown biochemical function, TMEM127, are required for SteD-dependent ubiquitination of mMHCII. Although evidently not involved in normal regulation of mMHCII, TMEM127 was essential for SteD to suppress both mMHCII antigen presentation in mouse dendritic cells and MHCII-dependent CD4+ T cell activation. We found that TMEM127 contains a canonical PPxY motif, which was required for binding to WWP2. SteD bound to TMEM127 and enabled TMEM127 to interact with and induce ubiquitination of mature MHCII. Furthermore, SteD also underwent TMEM127- and WWP2-dependent ubiquitination, which both contributed to its degradation and augmented its activity on mMHCII.


Assuntos
Proteínas de Bactérias/fisiologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Proteínas de Membrana/fisiologia , Salmonella typhimurium/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Ubiquitinação , Animais , Apresentação de Antígeno , Sistemas CRISPR-Cas , Linhagem Celular , Células Dendríticas/imunologia , Células Dendríticas/microbiologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Ligação Proteica , Infecções por Salmonella/imunologia , Infecções por Salmonella/microbiologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/microbiologia , Virulência
11.
Gut Microbes ; 11(3): 610-619, 2020 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-32036739

RESUMO

Gaining a complete understanding of transmission risk factors will assist in efforts to reduce new HIV infections, especially within the disproportionally affected population of men who have sex with men (MSM). We recently reported that the fecal microbiota of MSM elevates immune activation in gnotobiotic mice and enhances HIV infection in vitro over that of fecal microbiota from men who have sex with women. We also demonstrated elevation of the gut homing marker CD103 (integrin αE) on CD4+ T cells by MSM-microbiota. Here we provide additional evidence that the gut microbiota is a risk factor for HIV transmission in MSM by showing elevated frequencies of the HIV co-receptor CCR5 on CD4+ T cells in human rectosigmoid colon biopsies. We discuss our interest in specific MSM-associated bacteria and propose the influx of CD103+ and CCR5+ CD4+ T cells into the colon as a potential link between the MSM microbiota and HIV transmission.


Assuntos
Microbioma Gastrointestinal , Infecções por HIV/microbiologia , Infecções por HIV/transmissão , Minorias Sexuais e de Gênero , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Adolescente , Adulto , Antígenos CD/imunologia , Biópsia , Colo/imunologia , Colo/microbiologia , Feminino , Infecções por HIV/imunologia , Humanos , Cadeias alfa de Integrinas/imunologia , Masculino , Pessoa de Meia-Idade , Receptores CCR5/imunologia , Fatores de Risco , Comportamento Sexual , T-Linfocitopenia Idiopática CD4-Positiva/microbiologia , Adulto Jovem
12.
J Infect Chemother ; 26(2): 257-260, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31345742

RESUMO

Idiopathic CD4 lymphocytopenia (ICL) is a rare disease characterized by marked loss of CD4 T-cells without human immunodeficiency virus infection. CD4 T-cells play an important role in granuloma formation in cryptococcal infection. Thus far, among ICL patients, it has not been concluded definitely whether granuloma is formed or not. We report the case of a 39-year-old woman with ICL and disseminated cryptococcal infection with granuloma formation. She was referred to our department because of a lung mass, osteolytic lesion, and a subcutaneous mass identified on a computed tomography scan, and an elevated C-reactive protein level. Cryptococcus neoformans was isolated from the tissues. She also had marked CD4 lymphocytopenia (33 cells/µL), without human immunodeficiency virus infection. In a biopsy specimen of the lung mass, granulomas containing CD4 T-cells were observed. The cryptococcosis was treated with liposomal amphotericin B followed by fluconazole and she was found to be cured. The CD4 T-cell count was persistently low. This case showed that granulomas containing CD4 T-cells can be formed in ICL patients with cryptococcal infection despite very low CD4 T-cell counts.


Assuntos
Criptococose/diagnóstico , Granuloma/diagnóstico , T-Linfocitopenia Idiopática CD4-Positiva/diagnóstico , Adulto , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Biópsia/métodos , Contagem de Linfócito CD4 , Criptococose/complicações , Criptococose/tratamento farmacológico , Criptococose/imunologia , Cryptococcus neoformans/isolamento & purificação , Feminino , Fluconazol/uso terapêutico , Granuloma/complicações , Granuloma/imunologia , Granuloma/patologia , Humanos , Pulmão/diagnóstico por imagem , Síndrome de Sjogren/complicações , Síndrome de Sjogren/diagnóstico , T-Linfocitopenia Idiopática CD4-Positiva/complicações , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
13.
Front Immunol ; 10: 2502, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781092

RESUMO

Idiopathic T-CD4 lymphocytopenia (ICL) is a rare and heterogeneous syndrome characterized by opportunistic infections due to reduced CD4 T-lymphocytes (<300 cells/µl or <20% T-cells) in the absence of HIV infection and other primary causes of lymphopenia. Molecular testing of ICL has revealed defects in genes not specific to CD4 T-cells, with pleiotropic effects on other cell types. Here we report for the first time an absolute CD4 lymphocytopenia (<0.01 CD4+ T-cells/µl) due to an autosomal recessive CD4 gene mutation that completely abrogates CD4 protein expression on the surface membrane of T-cells, monocytes, and dendritic cells. A 45-year-old female born to consanguineous parents consulted because of exuberant, relapsing, and treatment-refractory warts on her hands and feet since the age of 10 years, in the absence of other recurrent infections or symptoms. Serological studies were negative for severe infections, including HIV 1/2, HTLV-1, and syphilis, but positive for CMV and EBV. Blood analysis showed the absence of CD4+ T-cells (<0.01%) with repeatedly increased counts of B-cells, naïve CD8+ T-lymphocytes, and particularly, CD4/CD8 double-negative (DN) TCRαß+ TCRγδ- T-cells (30% of T-cells; 400 cells/µl). Flow cytometric staining of CD4 using monoclonal antibodies directed against five different epitopes, located in two different domains of the protein, confirmed no cell surface membrane or intracytoplasmic expression of CD4 on T-cells, monocytes, and dendritic cells but normal soluble CD4 plasma levels. DN T-cells showed a phenotypic and functional profile similar to normal CD4+ T-cells as regards expression of maturation markers, T-helper and T-regulatory chemokine receptors, TCRvß repertoire, and in vitro cytokine production against polyclonal and antigen-specific stimuli. Sequencing of the CD4 gene revealed a homozygous (splicing) mutation affecting the last bp on intron 7-8, leading to deletion of the juxtamembrane and intracellular domains of the protein and complete abrogation of CD4 expression on the cell membrane. These findings support previous studies in CD4 KO mice suggesting that surrogate DN helper and regulatory T-cells capable of supporting antigen-specific immune responses are produced in the absence of CD4 signaling and point out the need for better understanding the role of CD4 on thymic selection and the immune response.


Assuntos
Antígenos CD4/deficiência , Antígenos CD4/genética , Mutação , T-Linfocitopenia Idiopática CD4-Positiva/genética , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Verrugas/genética , Verrugas/imunologia , Antígenos CD4/sangue , Linfócitos T CD4-Positivos/classificação , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Consanguinidade , Citotoxicidade Imunológica , Células Dendríticas/imunologia , Feminino , Genes Recessivos , Homozigoto , Humanos , Imunidade Humoral , Imunidade Inata , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Linhagem , T-Linfocitopenia Idiopática CD4-Positiva/patologia , Verrugas/patologia
14.
JCI Insight ; 4(14)2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31341106

RESUMO

Idiopathic CD4 lymphocytopenia (ICL) is a clinically heterogeneous immunodeficiency disorder defined by low numbers of circulating CD4+ T cells and increased susceptibility to opportunistic infections. CD8+ T cells, NK, and/or B cells may also be deficient in some patients. To delineate possible pathogenic cellular mechanisms in ICL, we compared immune system development and function in NOD-RAGKO-γcKO (NRG) mice transplanted with hematopoietic stem cells from patients with ICL or healthy controls. CD34+ hematopoietic stem cells from healthy controls and patients with ICL reconstituted NRG mice equally well. In contrast, PBMC transfers into NRG mice identified 2 ICL engraftment phenotypes, reconstituting and nonreconstituting (NR), based on the absence or presence of donor lymphopenia. For patients in the NR group, the distribution of lymphocyte subsets was similar in the peripheral blood of both the patient and the corresponding humanized mice. The NR-ICL group could be further divided into individuals whose CD3+ T cells had defects in proliferation or survival. Thus, ICL cellular pathogenesis might be classified by humanized mouse models into 3 distinct subtypes: (a) T cell extrinsic, (b) T cell intrinsic affecting proliferation, and (c) T cell intrinsic affecting survival. Humanized mouse models of ICL help to delineate etiology and ultimately to guide development of individualized therapeutic strategies.


Assuntos
Complexo CD3/metabolismo , Linfócitos T CD4-Positivos/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Adulto , Idoso , Animais , Antígenos CD34/imunologia , Antígenos CD34/metabolismo , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células , Separação Celular , Sobrevivência Celular/imunologia , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Voluntários Saudáveis , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/imunologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imunofenotipagem , Masculino , Camundongos , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , T-Linfocitopenia Idiopática CD4-Positiva/sangue , Quimeras de Transplante/imunologia
15.
Front Immunol ; 9: 1566, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30093899

RESUMO

Helminth infection induces Th2-biased immune responses and inhibitory/regulatory pathways that minimize excessive inflammation to facilitate the chronic infection of helminth in the host and in the meantime, prevent host hypersensitivity from autoimmune or atopic diseases. However, the detailed molecular mechanisms behind modulation on inflammatory diseases are yet to be clarified. Programmed death 1 (PD-1) is one of the important inhibitory receptors involved in the balance of host immune responses during chronic infection. Here, we used the murine model to examine the role of PD-1 in CD4+ T cells in the effects of Trichinella spiralis infection on collagen-induced arthritis (CIA). Mice infected with T. spiralis demonstrated higher expression of PD-1 in the spleen CD4+ T cells than those without infection. Mice infected with T. spiralis 2 weeks prior to being immunized with type II collagen displayed lower arthritis incidence and significantly attenuated pathology of CIA compared with those of uninfected mice. The therapeutic effect of T. spiralis infection on CIA was reversed by blocking PD-1 with anti-PD-1 antibody, associated with enhanced Th1/Th17 pro-inflammatory responses and reduced Th2 responses. The role of PD-1 in regulating CD4+ T cell differentiation and proliferation during T. spiralis infection was further examined in PD-1 knockout (PD-1-/-) C57BL/6 J mice. Interestingly, T. spiralis-induced alteration of attenuated Th1 and enhanced Th2/regulatory T cell differentiation in wild-type (WT) mice was effectively diminished in PD-1-/- mice characterized by recovered Th1 cytokine levels, reduced levels of Th2 and regulatory cytokines and CD4+CD25+Foxp3+ cells. Moreover, T. spiralis-induced CD4+ T cell proliferation suppression in WT mice was partially restored in PD-1-/- mice. This study introduces the first evidence that PD-1 plays a critical role in helminth infection-attenuated CIA in a mouse model by regulating the CD4+ T cell function, which may provide the new insights into the mechanisms of helminth-induced immunomodulation of host autoimmunity.


Assuntos
Artrite Experimental/imunologia , Artrite Experimental/parasitologia , Imunomodulação , Receptor de Morte Celular Programada 1/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Trichinella spiralis/imunologia , Animais , Modelos Animais de Doenças , Camundongos
16.
Ann Allergy Asthma Immunol ; 119(4): 374-378, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28958376

RESUMO

BACKGROUND: Idiopathic CD4 lymphocytopenia (ICL) is a rare condition characterized by an unexplained deficit of circulating CD4 T cells leading to increased risk of serious opportunistic infections. The pathogenesis, etiology, clinical presentation, and best treatment options remain unclear. OBJECTIVE: To describe the clinical presentation, treatment strategies, and outcome of patients with ICL seen in a single referral center. METHODS: In a retrospective study, from January 1993 to January 2014, the demographic characteristics, clinical presentation, and treatments of patients diagnosed with ICL were reviewed. RESULTS: Twenty-four patients (14 female [58%] and 10 male [42%]) were evaluated. The mean age was 45 ± 17.6 years (range 7-76 years). Mean CD4 and CD8 T-cell counts at the time of diagnosis were 119 ± 84/mm3 (range 4-294/mm3) and 219 ± 258/mm3 (range 7-630/mm3), respectively. Seventeen patients (71%) had opportunistic infections, 4 (17%) had malignancies, and 3 (13%) had unexplained demyelinating disease and neurologic problems. Most patients had normal levels of immunoglobulins. Thirteen patients had abnormally low to absent response to phytohemagglutinin, concanavalin A, and antigens (candida and tetanus). Three patients had resolution of warts and 1 had mycobacterial lung infection on interleukin-2 with increases in CD4 count. The 11 patients on trimethoprim and sulfamethoxazole had no further hospital admissions for infections. CONCLUSION: The pathogenesis of ICL remains unclear. Although only some patients are healthy, most patients present with opportunistic infections. There is no known standard treatment aside from prophylactic antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Doenças Desmielinizantes/tratamento farmacológico , Neoplasias/tratamento farmacológico , Infecções Oportunistas/tratamento farmacológico , T-Linfocitopenia Idiopática CD4-Positiva/tratamento farmacológico , Adolescente , Adulto , Idoso , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Criança , Doenças Desmielinizantes/complicações , Doenças Desmielinizantes/diagnóstico , Doenças Desmielinizantes/imunologia , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/diagnóstico , Neoplasias/imunologia , Infecções Oportunistas/complicações , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/imunologia , Estudos Retrospectivos , Sulfametoxazol/uso terapêutico , T-Linfocitopenia Idiopática CD4-Positiva/complicações , T-Linfocitopenia Idiopática CD4-Positiva/diagnóstico , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Trimetoprima/uso terapêutico
17.
Ann Allergy Asthma Immunol ; 119(4): 390-391.e1, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28958380
18.
J La State Med Soc ; 169(3): 85-87, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28644158

RESUMO

A 39 year-old male with a history of diabetes, retinitis pigmentosa, and genital warts presented with intractable occipital headaches accompanied with nausea and vomiting. The patient had markedly depressed CD4 counts. Furthermore the patient tested negative for HIV and HTLV 1/2 and had normal immunoglobulin levels. During hospital course the patient underwent a lumbar puncture and multiple imaging exams, including both CT and MR. Except for occasional nausea and vomiting controlled by therapeutic lumbar punctures, phenergan, and dilaudid the patient's hospital course was uncomplicated.


Assuntos
Abscesso Encefálico/diagnóstico por imagem , Hospedeiro Imunocomprometido , Meningite Criptocócica/diagnóstico por imagem , T-Linfocitopenia Idiopática CD4-Positiva/diagnóstico por imagem , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Adulto , Antifúngicos/uso terapêutico , Abscesso Encefálico/fisiopatologia , Abscesso Encefálico/terapia , Terapia Combinada , Seguimentos , Humanos , Hidromorfona/uso terapêutico , Interleucina-2/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Meningite Criptocócica/fisiopatologia , Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/etiologia , Prometazina/uso terapêutico , Doenças Raras , Medição de Risco , Punção Espinal/métodos , T-Linfocitopenia Idiopática CD4-Positiva/terapia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
19.
Curr Opin Hematol ; 22(1): 46-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25463685

RESUMO

PURPOSE OF REVIEW: Idiopathic CD4⁺ lymphocytopenia (ICL) is defined by the reduction of the main lymphocyte subtype in peripheral blood and CD4⁺ T cells below 300/µl in the absence of any secondary known causes of lymphopenia, including viral causes. The present review aims to state the latest available data on clinical, pathological and therapeutic aspects related to ICL, published from 1990 to 2014. The last observed clinical presentation and complications of ICL patients are described. The latest findings and possible mechanisms involved in the development of ICL features are included in the present review; however, pathogenesis of ICL has remained mainly obscured. Finally, recent therapeutic efforts considered in ICL patients are discussed. RECENT FINDINGS: In spite of the serious complications ICL has on the patients' quality of life, data on clinical, etiopathological and therapeutic behavior for ICL are very limited. On one side, an abnormal blood cell count may be the sole presentation; however, occurrence of disseminated malignant tumors is not uncommon in patients. Recent findings highlight the role of cytokines, especially interleukin-2, on features such as phenotype severity and responsiveness of the condition to therapy. In addition, some studies have suggested that a defect in hematopoietic stem cells may be involved in disease progression, an idea that is supported by the success of bone marrow transplantation in acquiring persistent remissions in ICL patients. SUMMARY: ICL is a hematologic condition of increasing importance due to its diverse clinical and pathological spectrum. Molecular studies have shown the presence of mutations involved in lymphocyte development as potential factors that may contribute to ICL occurrence. ICL patients could present either with common infections or really serious malignant conditions. The role of cytokines, especially interleukin-2, has emerged as one of the main possible mechanisms involved in clinical and pathological behavior of ICL. Today, the main therapeutic approaches are controlling life-threatening infections and underlying disorders along with efforts to cure ICL through rising CD4⁺ cell counts using cytokine interventions and transplantation.


Assuntos
Interleucina-2 , Mutação , T-Linfocitopenia Idiopática CD4-Positiva , Humanos , Infecções/genética , Infecções/imunologia , Infecções/patologia , Infecções/terapia , Interleucina-2/genética , Interleucina-2/imunologia , Interleucina-2/uso terapêutico , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/terapia , T-Linfocitopenia Idiopática CD4-Positiva/genética , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/patologia , T-Linfocitopenia Idiopática CD4-Positiva/terapia
20.
Artigo em Inglês | MEDLINE | ID: mdl-24974649
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