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Nateghi-Rostami M, Sohrabi Y. Memory T cells: promising biomarkers for evaluating protection and vaccine efficacy against leishmaniasis. Front Immunol 2024; 15:1304696. [PMID: 38469319 PMCID: PMC10925770 DOI: 10.3389/fimmu.2024.1304696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 02/08/2024] [Indexed: 03/13/2024] Open
Abstract
Understanding the immune response to Leishmania infection and identifying biomarkers that correlate with protection are crucial for developing effective vaccines. One intriguing aspect of Leishmania infection is the persistence of parasites, even after apparent lesion healing. Various host cells, including dendritic cells, fibroblasts, and Langerhans cells, may serve as safe sites for latent infection. Memory T cells, especially tissue-resident memory T cells (TRM), play a crucial role in concomitant immunity against cutaneous Leishmania infections. These TRM cells are long-lasting and can protect against reinfection in the absence of persistent parasites. CD4+ TRM cells, in particular, have been implicated in protection against Leishmania infections. These cells are characterized by their ability to reside in the skin and rapidly respond to secondary infections by producing cytokines such as IFN-γ, which activates macrophages to kill parasites. The induction of CD4+ TRM cells has shown promise in experimental immunization, leading to protection against Leishmania challenge infections. Identifying biomarkers of protection is a critical step in vaccine development and CD4+ TRM cells hold potential as biomarkers, as their presence and functions may correlate with protection. While recent studies have shown that Leishmania-specific memory CD4+ T-cell subsets are present in individuals with a history of cutaneous leishmaniasis, further studies are needed to characterize CD4+ TRM cell populations. Overall, this review highlights the importance of memory T cells, particularly skin-resident CD4+ TRM cells, as promising targets for developing effective vaccines against leishmaniasis and as biomarkers of immune protection to assess the efficacy of candidate vaccines against human leishmaniasis.
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Affiliation(s)
| | - Yahya Sohrabi
- Department of Cardiology I-Coronary and Peripheral Vascular Disease, Heart Failure, University Hospital Münster, Westfälische Wilhelms-Universität, Münster, Germany
- Department of Medical Genetics, Third Faculty of Medicine, Charles University, Prague, Czechia
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de Franca MNF, Rodrigues LS, Barreto AS, da Cruz GS, Aragão-Santos JC, da Silva AM, de Jesus AR, Palatnik-de-Sousa CB, de Almeida RP, Corrêa CB. CD4 + Th1 and Th17 responses and multifunctional CD8 T lymphocytes associated with cure or disease worsening in human visceral leishmaniasis. Front Immunol 2024; 15:1277557. [PMID: 38410517 PMCID: PMC10895669 DOI: 10.3389/fimmu.2024.1277557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 01/02/2024] [Indexed: 02/28/2024] Open
Abstract
Introduction In VL, a proinflammatory phenotype is typically associated with enhanced phagocytosis and a Th1 mediated immune response resulting in infection control. In contrast, an anti-inflammatory phenotype, associated with a predominant regulatory response, typically enables intracellular multiplication of Leishmania parasites and disease progression. Methods To investigate the impact of chemotherapy on Th2 and Th17 immune responses in patients with visceral leishmaniasis (VL), we assessed all combinations of intracellular expression of IFN-γ, IL-10, IL-4 and IL-17 in the CD4+ and CD8+ T cell populations of peripheral blood mononuclear cell (PBMC) samples from patients, after antigenic stimulation with Leishmania lysate, throughout treatment and follow-up. As increases in spleen and liver sizes and decreases in hematocrit, hemogloblin, erythrocytes, monocytes, leukocytes and platelets levels are strongly related to the disease, we studied the correlations between the frequencies of T cells producing the afore mentioned cytokines, individually and in combination, and these variables, as markers of disease or cure. Results We found that the frequency of IFN-γ-producingCD4+ T cells increased until the end of chemotherapy with Glucantime® or AmBisome ®, while IL-10, IL-4 and IL-17-producing CD4+ T cells peaked on day 7 following the start of treatment. Although the frequency of CD4+IL-17+ cells decreased during treatment an increase was observed after clinical cure. The frequency of CD4+ T cells producing only IFN-γ or IL-17 correlated with blood monocytes levels. Frequencies of double-producers of IFN-γ and IL-10 or IL-4 correlated positively with eosinophils and platelets levels. Together, this suggest that IFN-γ drives the immune response towards Th1 at cure. In contrast, and associated with disease or Th2 response, the frequency of CD4+ IL-10+ cells correlated positively with spleen sizes and negatively with circulating monocyte levels, while the frequency of CD4+ producing both IL-4 and IL-10 correlated negatively with platelets levels. The frequency of CD8+ single-producers of IFN-γ increased from day 21 to 90 while that of single-producers of IL-10 peaked on day 7, of IL-4 on day 30 and of IL-17, on day 180. IFN-γ expression in CD8+ single- and double-producers of cytokines was indicative of an immune response associated with cure. In contrast, frequencies of CD8+ double-producers of IL-4 and IL-10, IL-4 and IL-17 and IL-10 and IL-17 and producers of three and four cytokines, were associated with disease and were low after the cure. Frequencies of CD8+ T cells producing IFN-γ alone or with IL-17 were positively correlated with platelets levels. In contrast, as markers of disease: 1) frequencies of single producers of IL-10 correlated negatively with leukocytes levels, 2) frequencies of double producers of IL-4 and IL-10 correlated negatively with platelet, leukocyte, lymphocyte and circulating monocyte levels, 3) frequencies of triple-producers of IFN-γ, IL-4 and IL-10 correlated negatively with platelet, leukocyte and neutrophil levels and 4) frequencies of producers of IFN-γ, IL-4, IL-10 and IL-17 simultaneously correlated positively with spleen size, and negatively with leukocyte and neutrophil levels. Discussion Our results confirmed that the clinical improvement of VL patients correlates with the decrease of an IL-4 and IL-10 CD4+Th2 response, the recovery of CD4+ Th1 and Th17 responses and the frequency of CD8+ single-producers of IFN-γ and double producers of IFN-γ and IL-17.
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Affiliation(s)
- Mariana Nobre Farias de Franca
- Laboratory of Biology and Immunology of Cancer and Leishmania, Department of Morphology, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
| | - Lorranny Santana Rodrigues
- Laboratory of Biology and Immunology of Cancer and Leishmania, Department of Morphology, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
| | - Aline Silva Barreto
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Division of Immunology and Molecular Biology Laboratory, University Hospital/Empresa Brasileira de Serviços Hospitalares (EBSERBH), Federal University of Sergipe, Aracaju, Sergipe, Brazil
| | - Geydson Silveira da Cruz
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Division of Immunology and Molecular Biology Laboratory, University Hospital/Empresa Brasileira de Serviços Hospitalares (EBSERBH), Federal University of Sergipe, Aracaju, Sergipe, Brazil
| | - José Carlos Aragão-Santos
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Department of Physical Education, Federal University of Sergipe, Aracaju, Sergipe, Brazil
| | - Angela Maria da Silva
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Department of Medicine, Federal University of Sergipe, Aracaju, Sergipe, Brazil
| | - Amélia Ribeiro de Jesus
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Division of Immunology and Molecular Biology Laboratory, University Hospital/Empresa Brasileira de Serviços Hospitalares (EBSERBH), Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Department of Medicine, Federal University of Sergipe, Immunology Investigative Institute (III), INCT, CNPq, Aracaju, Sergipe, Brazil
| | - Clarisa B. Palatnik-de-Sousa
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Immunology Investigative Institute (III), Insititutos nacionais de Ciência e Tecnologia (INCT), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Rio de Janeiro, Brazil
- Graduate Program in Vegetal Biotechnology and Bioprocesses, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Roque Pacheco de Almeida
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Division of Immunology and Molecular Biology Laboratory, University Hospital/Empresa Brasileira de Serviços Hospitalares (EBSERBH), Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Department of Medicine, Federal University of Sergipe, Immunology Investigative Institute (III), INCT, CNPq, Aracaju, Sergipe, Brazil
| | - Cristiane Bani Corrêa
- Laboratory of Biology and Immunology of Cancer and Leishmania, Department of Morphology, Federal University of Sergipe, Aracaju, Sergipe, Brazil
- Graduate Program in Health Sciences, Federal University of Sergipe, Aracaju, Sergipe, Brazil
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Jesus MM, Lage DP, Vale DL, Freitas CS, Pimenta BL, Moreira GJL, Ramos FF, Pereira IAG, Bandeira RS, Ludolf F, Tavares GSV, Galdino AS, Duarte MC, Menezes-Souza D, Chávez-Fumagalli MA, Teixeira AL, Gonçalves DU, Roatt BM, Christodoulides M, Martins VT, Coelho EAF. Immunization with recombinant LiHyp1 protein plus adjuvant is protective against tegumentary leishmaniasis. Parasitol Res 2023; 122:2917-2931. [PMID: 37768367 DOI: 10.1007/s00436-023-07981-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023]
Abstract
Tegumentary leishmaniasis (TL) is the main clinical manifestation of leishmaniasis, and it can cause the infected hosts to self-healing cutaneous lesions until mutilating scars in mucosal membranes, particularly in the nose and throat. The treatment against disease presents problems, and the diagnosis is hampered by variable sensitivity and/or specificity of the tests. In this context, the development of prophylactic vaccines could be considered as a strategy to control the disease. Previously, we showed that the recombinant LiHyp1 protein plus adjuvant protected mice from infection with Leishmania infantum, which causes visceral leishmaniasis. In the present study, we tested whether rLiHyp1 could induce protection against infection with L. amazonensis, a parasite species able to cause TL. We immunized BALB/c mice with rLiHyp1 plus saponin (rLiHyp1/S) or incorporated in micelles (rLiHyp1/M) as adjuvants and performed parasitological and immunological evaluations before and after infection. Results showed that after in vitro stimulation from spleen cell cultures using rLiHyp1 or a Leishmania antigenic extract (SLA), rLiHyp1/S and rLiHyp1/M groups developed a Th1-type immune response, which was characterized by high levels of IFN-γ, IL-2, TNF-α and IL-12 cytokines, nitrite, and IgG2a isotype antibodies when compared to values found in the control (saline, saponin, micelles alone) groups, which showed higher levels of anti-SLA IL-4, IL-10, and IgG1 antibodies before and after challenge. In addition, mice receiving rLiHyp1/S or rLiHyp1/M presented significant reductions in the lesion average diameter and parasite load in the infected tissue and internal organs. Blood samples were collected from healthy subjects and TL patients to obtain PBMC cultures, which were in vitro stimulated with rLiHyp1 or SLA, and results showed higher lymphoproliferation and IFN-γ production after stimulus using rLiHyp1, as compared to values found using SLA. These results suggest that rLiHyp1 plus adjuvant was protective against experimental TL and could also be considered for future studies as a vaccine candidate against human disease.
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Affiliation(s)
- Marcelo M Jesus
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Daniela P Lage
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Danniele L Vale
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Camila S Freitas
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Breno L Pimenta
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Gabriel J L Moreira
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas/NUPEB, Departamento de Ciências Biológicas, Insituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Fernanda F Ramos
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Isabela A G Pereira
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Raquel S Bandeira
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Fernanda Ludolf
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Grasiele S V Tavares
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Alexsandro S Galdino
- Laboratório de Biotecnologia de Microrganismos, Universidade Federal de São João Del-Rei, Divinópolis, MG, Brazil
| | - Mariana C Duarte
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Av. Antônio Carlos, Belo Horizonte, Minas Gerais, 6627, Brazil
| | - Daniel Menezes-Souza
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Av. Antônio Carlos, Belo Horizonte, Minas Gerais, 6627, Brazil
| | - Miguel A Chávez-Fumagalli
- Computational Biology and Chemistry Research Group, Vicerrectorado de Investigación, Universidad Católica de Santa María, Urb. San José S/N, Umacollo, Arequipa, Peru
| | - Antônio L Teixeira
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Neuropsychiatry Program, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston (UTHealth), 1941 East Road, Houston, TX, USA
| | - Denise U Gonçalves
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Bruno M Roatt
- Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas/NUPEB, Departamento de Ciências Biológicas, Insituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Myron Christodoulides
- Neisseria Research Group, Molecular Microbiology, School of Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton General Hospital, Southampton, England
| | - Vívian T Martins
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Eduardo A F Coelho
- Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
- Departamento de Patologia Clínica, COLTEC, Universidade Federal de Minas Gerais, Av. Antônio Carlos, Belo Horizonte, Minas Gerais, 6627, Brazil.
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Alizadeh Z, Omidnia P, Altalbawy FMA, Gabr GA, Obaid RF, Rostami N, Aslani S, Heidari A, Mohammadi H. Unraveling the role of natural killer cells in leishmaniasis. Int Immunopharmacol 2023; 114:109596. [PMID: 36700775 DOI: 10.1016/j.intimp.2022.109596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 12/07/2022] [Accepted: 12/11/2022] [Indexed: 12/24/2022]
Abstract
NK cells are known as frontline responders that are efficient in combating several maladies as well as leishmaniasis caused by Leishmania spp. As such they are being investigated to be used for adoptive transfer therapy and vaccine. In spite of the lack of antigen-specific receptors at their surface, NK cells can selectively recognize pathogens, accomplished by the activation of the receptors on the NK cell surface and also as the result of their effector functions. Activation of NK cells can occur through interaction between TLR-2 expressed on NK cells and. LPG of Leishmania parasites. In addition, NK cell activation can occur by cytokines (e.g., IFN-γ and IL-12) that also lead to producing cytokines and chemokines and lysis of target cells. This review summarizes several evidences that support NK cells activation for controlling leishmaniasis and the potentially lucrative roles of NK cells during leishmaniasis. Furthermore, we discuss strategies of Leishmania parasites in inhibiting NK cell functions. Leishmania LPG can utilizes TLR2 to evade host-immune responses. Also, Leishmania GP63 can directly binds to NK cells and modulates NK cell phenotype. Finally, this review analyzes the potentialities to harness NK cells effectiveness in therapy regimens and vaccinations.
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Affiliation(s)
- Zahra Alizadeh
- Department of Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Farag M A Altalbawy
- National Institute of Laser Enhanced Sciences (NILES), University of Cairo, Giza 12613, Egypt; Department of Chemistry, University College of Duba, University of Tabuk, Duba 71911, Saudi Arabia
| | - Gamal A Gabr
- Department of Pharmacology and Toxicology, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center, Giza, Egypt
| | - Rasha Fadhel Obaid
- Department of Biomedical Engineering, Al-Mustaqbal University College, Babylon, Iraq
| | - Narges Rostami
- Department of Immunology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saeed Aslani
- Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Aliehsan Heidari
- Department of Parasitology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran.
| | - Hamed Mohammadi
- Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran; Department of Immunology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran.
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Abstract
IL-17 cytokine family members have diverse biological functions, promoting protective immunity against many pathogens but also driving inflammatory pathology during infection and autoimmunity. IL-17A and IL-17F are produced by CD4+ and CD8+ T cells, γδ T cells, and various innate immune cell populations in response to IL-1β and IL-23, and they mediate protective immunity against fungi and bacteria by promoting neutrophil recruitment, antimicrobial peptide production and enhanced barrier function. IL-17-driven inflammation is normally controlled by regulatory T cells and the anti-inflammatory cytokines IL-10, TGFβ and IL-35. However, if dysregulated, IL-17 responses can promote immunopathology in the context of infection or autoimmunity. Moreover, IL-17 has been implicated in the pathogenesis of many other disorders with an inflammatory basis, including cardiovascular and neurological diseases. Consequently, the IL-17 pathway is now a key drug target in many autoimmune and chronic inflammatory disorders; therapeutic monoclonal antibodies targeting IL-17A, both IL-17A and IL-17F, the IL-17 receptor, or IL-23 are highly effective in some of these diseases. However, new approaches are needed to specifically regulate IL-17-mediated immunopathology in chronic inflammation and autoimmunity without compromising protective immunity to infection.
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Affiliation(s)
- Kingston H G Mills
- School of Biochemistry and Immunology, Trinity Biomedical Science Institute, Trinity College Dublin, Dublin, Ireland.
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Costa-Madeira JC, Trindade GB, Almeida PHP, Silva JS, Carregaro V. T Lymphocyte Exhaustion During Human and Experimental Visceral Leishmaniasis. Front Immunol 2022; 13:835711. [PMID: 35585983 PMCID: PMC9108272 DOI: 10.3389/fimmu.2022.835711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 04/07/2022] [Indexed: 11/18/2022] Open
Abstract
A key point of immunity against protozoan Leishmania parasites is the development of an optimal T cell response, which includes a low apoptotic rate, high proliferative activity and polyfunctionality. During acute infection, antigen-specific T cells recognize the pathogen resulting in pathogen control but not elimination, promoting the development and the maintenance of a population of circulating effector cells that mount rapid response quickly after re-exposure to the parasite. However, in the case of visceral disease, the functionality of specific T cells is lost during chronic infection, resulting in inferior effector functions, poor response to specific restimulation, and suboptimal homeostatic proliferation, a term referred to as T cell exhaustion. Multiple factors, including parasite load, infection duration and host immunity, affect T lymphocyte exhaustion. These factors contribute to antigen persistence by promoting inhibitory receptor expression and sustained production of soluble mediators, influencing suppressive cell function and the release of endogenous molecules into chronically inflamed tissue. Together, these signals encourage several changes, reprogramming cells into a quiescent state, which reflects disease progression to more severe forms, and development of acquired resistance to conventional drugs to treat the disease. These points are discussed in this review.
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Affiliation(s)
- Juliana C. Costa-Madeira
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University from São Paulo, Ribeirão Preto, Brazil
| | - Gabrielly B. Trindade
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University from São Paulo, Ribeirão Preto, Brazil
| | - Paulo H. P. Almeida
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University from São Paulo, Ribeirão Preto, Brazil
| | - João S. Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University from São Paulo, Ribeirão Preto, Brazil
- Fiocruz-Bi-Institutional Translational Medicine Project, Ribeirão Preto, Brazil
| | - Vanessa Carregaro
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University from São Paulo, Ribeirão Preto, Brazil
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Abstract
Leishmaniasis is a zoonotic and vector-borne infectious disease that is caused by the genus Leishmania belonging to the trypanosomatid family. The protozoan parasite has a digenetic life cycle involving a mammalian host and an insect vector. Leishmaniasisis is a worldwide public health problem falling under the neglected tropical disease category, with over 90 endemic countries, and approximately 1 million new cases and 20,000 deaths annually. Leishmania infection can progress toward the development of species–specific pathologic disorders, ranging in severity from self-healing cutaneous lesions to disseminating muco-cutaneous and fatal visceral manifestations. The severity and the outcome of leishmaniasis is determined by the parasite’s antigenic epitope characteristics, the vector physiology, and most importantly, the immune response and immune status of the host. This review examines the nature of host–pathogen interaction in leishmaniasis, innate and adaptive immune responses, and various strategies that have been employed for vaccine development.
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