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Molecular mechanisms and effector functions of the human cathelicidin host defence peptide LL-37: modulation of cytokine IL-32γ-induced responses and inflammatory arthritisChoi, Ka-Yee Grace 03 April 2017 (has links)
Current therapies for chronic inflammatory diseases often abrogate the immune functions required to fight infections. Human cathelicidin host defence peptide (HDP) LL-37 selectively suppresses pathogen-induced inflammation, without compromising resistance to infections. These unique dual abilities of LL-37 make it a promising candidate as an alternative therapeutic for treating chronic inflammatory diseases. The objective of this study was to investigate the effects of LL-37 and its derivative peptide IG-19 in cytokine-mediated inflammation. I demonstrated that LL-37 and IG-19 selectively suppressed cytokine IL-32γ-induced pro-inflammatory cytokines, without compromising the production of anti-inflammatory cytokines, and chemokines in human PBMC and macrophages. However, significant quantitative differences between LL-37 and IG-19-mediated chemokine productions suggested that the mechanisms underlying the activity of these two peptides were different.
I showed that both peptides suppressed IL-32γ-mediated phosphorylation of the Src-kinase FYN(Y420), known to enhance inflammation. Contrastingly, phosphorylation of the dual phosphatase MKP-1(S359), a negative regulator of inflammation, was enhanced in response to both peptides. Similarly, both peptides increased the activity of p44/42MAPK, which phosphorylates and stabilizes MKP-1. These results suggested that MKP-1 may be a critical mediator of the immunomodulatory activity of these peptides.
Bioinformatic interrogation revealed that direct interacting protein partners of MKP-1 were overrepresented in MAPK and NF-κB signalling pathways. Both peptides enhanced the phosphorylation of p38MAPK. However, contrasting to LL-37, IG-19 did not mediate the phosphorylation of JNK MAPK and IKK-α signaling intermediates involved in inflammation. This was consistent with observations that chemokine production was significantly lower in response to IG-19 compared to LL-37. These results suggested that IG-19 may be a better immunomodulatory therapeutic candidate compared to LL-37.
As cytokine-mediated inflammation plays critical roles in the disease pathogenesis of inflammatory arthritis, I examined the effects of exogenous administration of IG-19 in a murine model of collagen-induced arthritis. Administration of IG-19 decreased disease severity, suppressed pro-inflammatory cytokines and anti-collagen antibodies, and mitigated cartilage destruction in the CIA mice. These results provide a rationale to further develop IG-19 as a therapeutic agent for chronic inflammatory arthritis. The advantage of HDP based therapy is the potential to control inflammation without compromising the patient’s ability to resolve infections. / May 2017
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Avaliação do efeito da expressão do gene da interleucina 32 (IL-32) humana em modelo murino de infecção por Leishmania (Leishmania) amazonensis / Evaluation of the effect of the gene expression of interleukin 32 (IL-32) human in a murine model of infection by Leishmania (L.) amazonensisSilva, Muriel Vilela Teodoro 24 August 2016 (has links)
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Previous issue date: 2016-08-24 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / IL-32 is a proinflammatory cytokine which has different isoforms. IL-32γ isoform is the most
powerful and was detected in lesions of patients with cutaneous leishmaniasis. Murine cells
respond to IL-32, however mice lack the gene for this cytokine. To understand the role of IL-
32 in Leishmania (L.) amazonensis, we used transgenic mice for human IL-32γ (IL-32γTg).
C57BL/6 mice (WT) and C57BL/6 IL-32γTg were infected with L. amazonensis promastigotes
in the ear. The lesion development was followed weekly with a digital caliper (measured in
mm of injury). After 3, 6 and 9 weeks, the animals were euthanized for tissue parasitism
analysis by the limiting dilution technique, in infected ears, draining lymph node and spleen of
mice. The draining lymph node cells were incubated (48 h) in the presence or absence of L.
amazonensis antigen (Ag) for analysis of cytokines by ELISA. IL-32γTg mice present IL-32
production in spleen, liver, lymph node and ear. IL-32γTg mice have a lower injury than the
WT mice during the third week of infection. From the 5th to the 9th week of infection, the two
groups had similar lesion development profiles. Interestingly, in the 3rd week of infection, the
parasitic load in the lesion of IL-32γTg mice was 100 times greater than that of WT mice.
After three weeks, IL-32γTg mice maintained the same parasitic load up to nine weeks. In WT
mice, however, the number of parasites increased exponentially during weeks evaluated. The
parasite load in the spleen and lymph node was lower in IL-32γTg mice when compared with
WT mice. There was no difference in histological sections of the lesions in WT and IL-32γTg
mice infected with L. amazonensis. We did not observe differences between WT and IL-32γTg
groups on the product -10) by lymph node cells stimulated
with Ag, in the 3rd, 6th and 9th week of infection. Our data suggest that IL-32γ favors
infection by L. amazonensis in the early stages, allowing the growth of the parasites.
However, this cytokine seems to limit the growth and spread of parasites in the later stages
of infection. In vitro analyzes show the similar percentage of infected cells and the number of
parasites per infected cell in WT macrophages and IL-32γTg after 3 and 48h of infection with
L. amazonensis. However, the production of NO by macrophages seems to be lower in IL-
32γTg mouse cells during infection with L. amazonensis. Understanding the mechanisms by
which IL-32γ modulates Leishmania amazonensis infection in mice is essential to define the
components that control cutaneous leishmaniasis caused by this specie in humans. / A IL-32 é uma citocina pró-inflamatória que apresenta diferentes isoformas. A isoforma IL-
32γ é a mais potente e foi detectada em lesões de pacientes com leishmaniose tegumentar
americana. Células murinas respondem à IL-32, no entanto, camundongos não têm o gene
para essa citocina. Para entender o papel da IL-32 na infecção por Leishmania (Leishmania)
amazonensis, foram utilizados camundongos transgênicos para a IL-32γ humana (IL-32γTg).
Camundongos C57BL/6 (WT) e C57BL/6 IL-32γTg foram infectados com formas
promastigotas de L. amazonensis na orelha. O desenvolvimento da lesão foi acompanhado
semanalmente com paquímetro digital (medida em mm de lesão). Após 3, 6 e 9 semanas, os
animais foram eutanasiados para análise de parasitismo tecidual, pela técnica de diluição
limitante, nas orelhas infectadas, no linfonodo drenante e no baço dos camundongos. As
células do linfonodo drenante foram incubadas (48 h), na presença ou ausência de antígeno
de L. amazonensis (Ag), para análise de citocinas pela técnica de ELISA. Camundongos IL-
32γTg apresentam produção de IL-32 no baço, fígado, linfonodo e orelha. Camundongos IL-
32γTg apresentam uma lesão menor do que a lesão dos camundongos WT, na terceira
semana de infecção. Da 5ª até a 9a semana de infecção, os dois grupos apresentaram perfis
semelhantes de desenvolvimento da lesão. Curiosamente, na 3ª semana de infecção, a carga
parasitária na lesão do camundongo IL-32γTg era 100 vezes maior do que a dos
camundongos WT. Após três semanas, os camundongos IL-32γTg mantiveram a mesma
carga parasitária até nove semanas. Em camundongos WT, no entanto, o número de
parasitos aumentou exponencialmente durante as semanas avaliadas. A carga parasitária do
linfonodo e no baço foi menor nos camundongos IL-32γTg, quando comparado com
camundongos WT. Não foi observada diferença nos perfis histológicos das lesões nos
camundongos WT e IL-32γTg infectados por L. amazonensis. Não foi observada nenhuma
diferença entre os grupos WT e IL-32γTg em relação à produção de citocinas (IFNγ, TNFα e
IL-10), pelas células dos linfonodos estimuladas com Ag, na 3a, 6a e 9a semana de infecção.
Os nossos dados sugerem que a IL-32γ favorece a infecção por L. amazonensis nas fases
iniciais, permitindo o crescimento do parasito; no entanto, essa citocina parece limitar o
crescimento e a disseminação dos parasitos nas fases mais tardias da infecção. As análises in
vitro mostraram porcentagem de células infectadas e número de parasitas por célula
infectada semelhantes nos macrófagos dos WT e IL-32γTg com 3 e 48h de infecção por L.
amazonensis. Entretanto, a produção de NO por macrófagos parece ser menor nas células de
camundongos IL-32γTg durante a infecção por L. amazonensis. Compreender os mecanismos
pelos quais a IL-32γ modula a infecção por L. amazonensis nos camundongos é fundamental
para a definição dos componentes que controlam a leishmaniose tegumentar causada por
esta espécie em seres humanos.
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Avaliação da participação de citocinas (interleucina 32, interleucina 10, fator de necrose tumoral) e receptores similares a Toll (TLR 4) na infecção por Leishmania (Viannia) sp. / Evaluation of the participation of cytokines (interleukin-32, interleukin-10, tumor necrosis factor) and Toll-Like receptors (TLR 4) in infection by Leishmania (V.) sp.Galdino Júnior, Hélio 26 July 2013 (has links)
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Previous issue date: 2013-07-26 / American Tegumentary Leishmaniasis (ATL) is a disease caused by protozoa Leishmania. In Brazil, the most
prevalent species is L. (Viannia) braziliensis. Several cytokines and receptors are involved in immunopathogenesis of
ATL, however, the role of interleukin 32 (IL-32) was not investigated in this disease. Besides, toll-like receptors
(TLR) were poorly evaluated in Leishmania infection, especially when it is caused by L. (V.) braziliensis. The aim of
the present study was to evaluate IL-32, TNF and IL-10 expression in ATL lesions; the induction of IL-32 by L. (V.)
braziliensis amastigotes in human peripheral blood mononuclear cells (PBMC) cultures as well as the involvement of
TLR4 in monocyte/macrophage response to L. (V.) brazilienis amastigotes. Biopsies fragments from cutaneous and
mucosal lesion and healthy tissues were used to investigate the subgenus of the parasites by PCR-RFLP assay;
expression of IL-32, TNF and IL-10 was assayed by immunohistochemistry and expression of IL-32 isoforms
, TNF and IL-10 was analysed by qRT-PCR. The PBMC were cultured with L. (V.) braziliensis amastigotes
in the absence or presence of IFN and IL-32 induction was assayed by qRT-PCR; and TNF and IL-10, by ELISA.
TLR4 was neutralized by monoclonal antibodies and lipopolysaccharide (LPS) was used as TLR4 agonist. The
expression of TLR4 in monocyte/macrophages was evaluated by flow cytometry. Thirty five patients were evaluated,
23 with cutaneous leishmaniasis (CL) and 12 with mucosal leihsmaniasis (ML). All parasite positive samples
contained L. (Viannia) sp. The expression of IL-32 (protein and mRNA) was similar in CL and ML lesions but was
higher than in health tissues. Only IL-32 was detected. The proteins TNF and IL-10 were detected in similar levels in
CL and ML lesions, but TNF mRNA was present in higher levels in ML (4.069x) than in CL lesions (141 x, p < 0.05).
L. (V.) braziliensis amastigotes induced IL-32, TNF and IL-10 in IFN pre-treated PBMC. The production of TNF
and IL-10 was TLR4 dependent and treatment of PBMC with LPS further increased the production of TNF induced by
amastigotes (p < 0.05). However, LPS did not altere the IL-10 production. Treatment with IFN enhanced the
percentage of TLR4+ monocyte/macrophage (p < 0.05), which was decreased following incubation with amastigotes (p
= 0.06). The results showed that IL-32 is produced during L. (Viannia) infection and TLR4 mediates L. (V.)
braziliensis amastigote-induced TNF and IL-10 production in human PBMC. Moreover, the data suggest that
amastigotes can lead to TLR4 internalization what can allow parasite to evade of innate immune response. This study
indicates that IL-32 and TLR4 are important players in human infection caused by L. (Viannia), especially L. (V.)
braziliensis. Whether TLR4 is also important to IL-32 production by human monocytes/macrophages deserves further
investigation. / A leishmaniose Tegumentar Americana (LTA) é uma doença infecto-parasitária, causada, no Brasil, principalmente
pela espécie Leishmania (Viannia) braziliensis. Na imunopatogenia da LTA participam várias citocinas e receptores.
A interleucina 32 (IL-32) é uma citocina pro-inflamatória, cuja participação na LTA ainda não foi investigada. O papel
dos receptores similares a Toll (TLR) na LTA tem sido pouco investigado, especialmente considerando infecção por L.
(V.) braziliensis. O objetivo deste estudo foi avaliar a expressão da IL-32, do TNF e da IL-10 nas lesões de pacientes
com LTA, a indução de IL-32 por formas amastigotas de L. (V.) braziliensis em células mononucleares (CMN)
humanas, bem como avaliar a participação do TLR4 na infecção de monócitos/macrófagos humanos com formas
amastigotas de L. (V.) brazilienis. Fragmentos de lesões cutâneas ou mucosas de pacientes com LTA e tecidos sadios
foram obtidos, sendo usados para a determinação do subgênero de Leishmania, usando a PCR-RFLP; para análise de
IL-32, TNF e IL-10 por imunoistoquímica; e para análise da expressão das isoformas da IL-32, do TNF e da
IL-10, por qRT-PCR. As CMN foram cultivadas com amastigotas de L. (V.) braziliensis, na ausência ou presença de
IFN e a indução de IL-32 foi avaliada por qRT-PCR e TNF e IL-10, por ELISA. Para neutralização de TLR4 foram
usados anticorpos monoclonais e lipopolissacarídeo (LPS), como agonista de TLR4. A expressão de TLR4 nos
monócitos/macrófagos presentes nas CMN foi avaliada por citometria de fluxo. Foram analisados 35 pacientes sendo
23 leishmaniose cutânea (LC) e 12 com leishmaniose mucosa (LM). Todas as amostras PCR positivas continham
parasitos pertencentes ao subgênero Viannia. Nas lesões de pacientes com LC e LM foi detectada uma maior
expressão tanto da proteína quanto do mRNA da IL-32 do que nos tecidos controles, porém níveis similares foram
encontrados nas duas formas clínicas. Somente a isoforma IL-32 foi detectada. As proteínas TNF e a IL-10 foram
detectadas nas lesões, em níveis similares na LC e na LM, porém, o mRNA do TNF estava em níveis mais elevados
nas lesões de LM (4.069 vezes) do que nas lesões de LC (141 vezes, p < 0,05). As formas amastigotas de L. (V.)
braziliensis indiziram a produção de IL-32 TNF e de IL-10 nas CMN pré-tratadas com IFN. A produção de TNF e
IL-10 foi dependente de TLR4 e o tratamento das CMN com LPS aumentou a produção do TNF induzido pelas
amastigotas (p < 0,05), mas não alterou a produção da IL-10. A incubação com IFN aumentou significantemente a
porcentagem de monócitos/macrófagos TLR4+ (p < 0,05), a qual foi diminuída pelas formas amastigotas (p = 0,06). Os
resultados mostram que a IL-32 é produzida durante a infecção humana causada por L. (Viannia) e evidenciam a
participação de TLR4 na indução de TNF e IL-10 em CMN humanas por formas amastigotas de L. (V.) braziliensis.
Ainda, os dados sugerem que as formas amastigotas causam a internalização dos TLR4, o que pode ser um mecanismo
de evasão da resposta imune. Portanto, a IL-32 e o TLR4 parecem importantes componentes na infecção humana
causada por L. (Viannia), especialmente L. (V.) braziliensis, podendo contribuir para a imunopatogenia ou para o
controle da infecção.
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Exploring the role of IL-32 in premature age-related cardiovascular diseases in HIV-infected individualsZaidan, Sarah 04 1900 (has links)
No description available.
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Rôle de l'IL-32 dans l'inflammation chronique, la sénescence et le dysfonctionnement cellulaire lié aux maladies cardiovasculaires chez les personnes vivant avec le VIH-1Bunet, Rémi 12 1900 (has links)
L’épidémie causée par le virus du VIH-1 touche actuellement 38,4 millions de personnes dans le monde dont environ 63000 au Canada. Depuis 1996 et la mise en pratique de la thérapie antirétrovirale combinée, l’espérance de vie des personnes vivant avec le VIH a augmenté significativement jusqu’à s’approcher de celle de la population générale. Actuellement, 10% des personnes vivant avec le VIH (PVVIH) dans le monde ont plus de 50 ans et ce chiffre augmente à 50% pour les États-Unis et le Canada. Cette population vieillissante avec le VIH est exposée à un risque plus élevé de développer des comorbidités associées à l’infection chronique. Le développement de meilleures méthodes de gestion des comorbidités est nécessaire afin d’améliorer la qualité de vie des personnes vieillissant avec le VIH. Cela passe notamment par une meilleure connaissance des processus inflammatoires impliqués, la recherche de biomarqueurs et de cibles thérapeutiques.
Nous nous sommes intéressés à l’interleukine-32, une cytokine pro-inflammatoire exprimée en de multiples isoformes et dont l’expression est augmentée dans le sang des PVVIH. Nous avons remarqué que les isoformes d’IL-32β et γ diminuaient l’expression du CD96 à la surface des cellules TCD8+. Nous avons déterminé que la perte de son expression était associée avec une diminution de l’expression de CD28 et CD27 et une augmentation de l’expression de CD57. Les cellules TCD8+ exprimant peu de CD96 avaient une diminution de leur capacité de prolifération et les cellules TCD8+ spécifiques au VIH exprimant peu de CD96 répondaient moins efficacement aux peptides du VIH. Nos résultats indiquent que le CD96 est un marqueur des cellules compétentes contre le VIH et que la perte de son expression peut être utilisée comme un marqueur de la dysfonction et de la sénescence des cellules TCD8+.
Nous avons ensuite étudié le rôle de l’IL-32 dans le développement des maladies cardiovasculaires via son impact sur les cellules endothéliales de l’artère coronaire. Nous avons pu montrer que les isoformes de l’IL-32 β et γ ont un impact partiel sur la production de cytokines pro-inflammatoires par les cellules endothéliales. Cependant, ces isoformes d’IL-32 augmentent l’expression des molécules d’adhérence et la production des chimiokines par les cellules endothéliales. Nous avons déterminé que ces isoformes induisent la dysfonction cellulaire et contribuent au recrutement des monocytes et à leur transmigration. Nous avons également déterminé que l’expression des isoformes d’IL-32 corrèle avec la rigidité artérielle de la carotide autant chez les personnes vivant avec le VIH que dans la population générale. Ces résultats suggèrent qu’IL-32 pourrait constituer une cible thérapeutique pour atténuer l’inflammation chronique, la sénescence cellulaire et la dysfonction cellulaire associés au développement des maladies cardiovasculaires.
Enfin nous nous sommes intéressés à l’utilisation des acides gras à chaine courte dans la réduction de l’inflammation des cellules endothéliales. Nous avons découvert que plusieurs acides gras à chaine courte ont le potentiel de diminuer les signes de dysfonction des cellules endothéliales comme l’expression de leurs molécules d’adhérence et leur sécrétion de cytokines et de chimiokines après stimulation par les isoformes d’IL-32β et γ. / As of 2023, the HIV-1 epidemic is affecting 38,4 million people worldwide and 63000 in Canada. Since 1996, introduction of the combined antiretroviral therapy led to a very impressive increase in the lifespan of PLWH, which approaches the general population. Currently, 10% of PLWH are over the age of 50 years worldwide and this number is increased to 50% in the US and Canada. This aging population of PLWH is exposed to an increased prevalence of comorbidities associated with the chronic infection on top of the normal age-associated co-morbidities. Thus, improving the management of comorbidities is mandatory to improve quality of life of PLWH. This can be achieved by a better understanding of the inflammatory process involved along with the discovery of new biomarkers of disease progression and identifying new therapeutic targets.
To this end, we got interested in interleukine-32 (IL-32), a pro-inflammatory cytokine expressed in multiple isoforms and upregulated in the blood of PLWH and is associated with disease progression in PLWH. We discovered that IL-32β and γ decreases the expression of CD96, a transmembrane glycoprotein receptor, at the surface of CD8 T cells. We determined that the loss of CD96 expression was associated with a senescence phenotype translated by the reduction in the expression of CD27 and CD28 and an upregulation in the expression of CD57. CD8+ T cells expressing low CD96 had their proliferative capabilities altered and responded poorly to HIV-1 antigen recall. Our results suggest that CD96 is a biomarker for competent CD8+ T cells in the context of HIV-1 infection and that its decreased expression by IL-32-mediated mechanisms may lead to CD8+ T cell dysfunction and senescence. These mechanisms are likely to contribute to the persistent inflammation and its associated comorbidities in the aging population of PLWH.
We then investigated the role of IL-32 in the development of cardiovascular diseases by looking at its impact on coronary artery endothelial cells (CAEC). We observed that IL-32β and γ have a partial impact on CAEC cytokine production. However, theses isoforms increased the expression of adhesion molecules and production of chemokines involved in leukocyte recruitment by the CAEC. In this context, we determined that IL-32β and γ induce the dysfunction of CAEC and lead to monocyte recruitment. We also observed that IL-32 isoforms expression correlates with carotid artery stiffness in both PLWH and in the general population. These results suggest that IL-32 could be considered as a therapeutic target to attenuate inflammation, cellular senescence, and dysfunction of endothelial cells, which are processes linked to the development of cardiovascular diseases.
Finally, we got interested in the use of short chains fatty acids (SCFA), a group of gut metabolites that we previously shown to be decreased in PLWH with cardiovascular disease, to reduce the impact of IL-32 isoforms on endothelial cells. We discovered that several SCFA have the potential to diminish the impact of IL-32 on markers of CAEC dysfunction, such on the expression of their adhesion molecule and chemokine secretion after stimulation by IL-32β and γ.
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Avaliação de citocinas no sangue periférico e expressão gênica em pacientes com Esclerose Múltipla tratados com Interferon-beta / Evaluation of peripheral blood cytokines and gene expression in patients with Multiple Sclerosis treated with Interferon-betaOliveira, Iara Barreto Neves 29 September 2017 (has links)
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Previous issue date: 2017-09-29 / Introduction. Multiple Sclerosis (MS) is a Central Nervous System disease, mediated by the Immune System, whose
symptoms occur in episodes of relapses. Interferon-beta (IFN-β) is considered a safe treatment for the reduction of
relapses, but its mechanisms of action have not yet been clear. Studies have shown involvement of tumor necrosis
factor alpha (TNF-α) and of Interleukin-10 (IL-10) in the immunopathogenesis of MS. The role of IL-32, a proinflammatory
cytokine has role on several chronic inflammatory diseases, was not elucidated in MS. The effect of
IFN-β on these cytokines and disease severity, as measured by the Expanded Disability Status Scale (EDSS), has not
yet been established. Objective. The objective of the present study was to evaluate TNF-α, IL-10 and IL-32γ
concentrations in the peripheral blood and gene expression of patients with IFN-β. Methods. The sample were
patients of the Department of Neurology of the Clinics Hospital of the Federal University, and healthy individuals.
Blood collection, blood culture with lipopolysaccharide (LPS), Toll 4 receptor agonist (TLR4), and PAM3Cys, TLR2
agonist, and the quantification of cytokines by real-time polymerase chain reaction were performed. Mann Whitney
tests were used for statistical analysis of unpaired data, Wilcoxon for paired samples and Spearman's correlation test,
adopting significance level p <0.05. Results. Of the 30 MS patients, 19 were treated with IFN-β and 11, untreated,
with a mean age of 40.52 and 42 years, respectively, and female prevalence. TNF-α did not differ between groups but
it was less produced after stimulation with Pam3Cys in treated patients compared to controls and untreated patients. IL-
10 concentrations were higher in cultures with LPS in patients treated compared to healthy controls. The mean EDSS
of patients treated with IFN-β and untreated did not differ, and the correlation between and TNF-α and IL-10
concentrations produced in blood cultures and EDSS was not significant in the patients. There was a significant
correlation between TNF-α concentrations and disease time in untreated patients in non-stimulated cultures and those
with TLR2 agonist stimulus. Gene expression of IL-32γ was higher in IFN-β treated patients compared to controls. The
gene expression of cytokines correlated positively and significantly in patients and controls and the IL-10 expression
was correlated negative e significantly with the disease time in untreated patients. Conclusions. IFN-β reduced
patients' response to Pam3Cys. IL-10 was higher in treated patients relative to controls. The correlations were not
conclusive about the possible association between these cytokines and the clinic parameters of the disease. IL-32γ was
higher in patients treated with IFN-β than in healthy subjects. / Introdução. A Esclerose Múltipla (EM) é uma doença do Sistema Nervoso Central, mediada pelo Sistema
Imune,cujos sintomas ocorremem episódios de surtos.OInterferon-beta (IFN-β) é considerado um tratamento seguro
para redução dos surtos, masseus mecanismos de ação ainda não foram bemesclarecidos. Estudos mostraram
participaçãodo fator de necrose tumoral alfa (TNF-α) e da Interleucina-10 (IL-10) na imunopatogênese da EM. O papel
da IL-32, citocina pró-inflamatória atuante emvárias doenças inflamatórias crônicas, não foi elucidado na EM. O efeito
do IFN-β nestas citocinas e na gravidade da doença, medida pela Escala do Estado de Incapacidade Expandida
(EDSS), ainda não foi estabelecido. Objetivo.O objetivo do presente estudo foi avaliar as concentrações de TNF-α, IL-
10 e IL-32γ no sangue periférico de pacientes com EM tratados com IFN-β e não tratados. Métodos.Foram recrutados
portadores da doença, no Serviço de Neurologia do Hospital das Clínicas da Universidade Federal,e indivíduos sadios.
Foi feita a coleta de sangue, hemoculturas com lipopolissacarídeo (LPS), agonista do receptor do tipo Toll 4 (TLR4), e
PAM3Cys, agonista de TLR2, e a quantificação gênica das citocinas por reação em cadeia da polimerase em tempo
real. Foram utilizados os testes Mann Whitney, para análise estatísticados dados não pareados, Wilcoxon para as
amostras pareadas e o teste de correlação de Spearman, adotando nível de significância p<0,05. Resultados. Dos 30
pacientes com EM, 19 eram tratados com IFN-β e 11, não tratados, com idade média de 40,52 e 42 anos, anos,
respectivamente, e prevalência do sexo feminino. As concentrações de IL-10 foram mais elevadasnas culturas dos
pacientes tratados com IFN-β estimuladas com LPS comparado aos controles sadios.TNF-α não diferiu entre os
grupos, mas foi menos produzido após estimulação com Pam3Cys nos pacientes tratados comparado aos controles e
aos pacientes não tratados. O EDSS médio dos pacientes tratados com IFN-β e dos não tratados não diferiu, e a
correlação entre e as concentrações de TNFα e IL-10 produzidas nas hemoculturas e o EDSS não foi significante nos
pacientes. Houve correlação significante entre as concentrações de TNF-α e o tempo de doença nos pacientes não
tratados nas culturas não estimuladas e naquelas com estímulo de agonista de TLR2. A expressão gênica de IL-32γ foi
mais elevada nos pacientes tratados com IFN-β comparado aos controles. As expressões gênicas das citocinas se
correlacionaram positiva e significantemente nos pacientes e controles e a expressão de IL-10 se correlacionou
negativa e significantemente com o tempo de doença nos pacientes não tratados. Conclusões. O IFN-β reduziu a
resposta dos pacientes ao Pam3Cys. IL-10 foi mais elevada nos pacientes tratados em relação aos controles. As
correlações não foram conclusivas sobre a possível associação entre essas citocinas e os parâmetros clínicos da doença.
IL-32γ foi mais elevada nos pacientes tratados com IFN-β em relação às pessoas sadias.
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Cellular and Molecular Biomarkers of Intestinal Pathology Promoting Cardiovascular Disease in People with HIV Receiving Antiretroviral TherapyMoreira Gabriel, Etiene 04 1900 (has links)
Le virus de l'immunodéficience humaine de type 1 (VIH-1) a causé la mort d'environ 40,4 millions de personnes à travers le monde. Malgré les progrès de la thérapie antirétrovirale, qui a transformé le panorama de l'épidémiologie du VIH, le virus continue de représenter un défi sanitaire significatif à l'échelle mondiale, tel que démontré par les 1,3 million de nouveaux cas à la fin de 2022, augmentant le nombre à 39 millions de personnes vivant avec le VIH à ce jour. Les effets nuisibles du VIH-1 vont au-delà du développement du syndrome d'immunodéficience acquise, exacerbant notamment l'inflammation chronique et augmentant le risque de maladies cardiovasculaires chez les personnes infectées. Bien que la thérapie antirétrovirale ait joué un rôle significatif dans la gestion du virus mondialement, l’absence persistante d’un remède définitif et les problèmes liés à l’inflammation chronique et à la dérégulation du système immunitaire soulignent la nécessité cruciale de poursuivre la recherche.
Cette thèse a étudié la relation entre l'infection par le VIH-1, la dérégulation immunitaire de la muqueuse intestinale, l'expression des cytokines, et l'inflammation systémique, avec un focus sur le risque de développement des maladies cardiovasculaires chez les personnes âgées recevant la thérapie antirétrovirale. Plus précisément, les dynamiques immunitaires complexes impliquant les cellules épithéliales intestinales, les cellules Th17, la cytokine pro-inflammatoire interleukine (IL)-32 au sein des tissus lymphoïdes associés au tube digestif, et l'existence de cellules intestinales dans la périphérie ont été évaluées. Nous avions pour objectif de comprendre comment le VIH-1 perpétue l'inflammation chronique et d’identifier de nouvelles cibles potentielles pour des interventions afin d'atténuer les conséquences à long terme pour les personnes avec VIH.
Le premier projet s'est concentré sur le suivi de l'expression des isoformes de l'IL-32 dans le côlon des personnes avec VIH traités par thérapie antirétrovirale par rapport aux individus non infectés. Nous avons associé l'IL-32β à une diminution de l'expression de la cytokine caractéristique des Th17, l'IL-17A. Ce déséquilibre est proposé comme un facteur important contribuant à l'inflammation et à la compromission potentielle de l'intégrité de la barrière intestinale. La recherche met en évidence le rôle de l'IL-32 dans la promotion de l'inflammation par son interaction avec d'autres cytokines pro-inflammatoires, ce qui pourrait conduire à des dommages tissulaires et augmenter le risque de maladies cardiovasculaires.
Le deuxième projet a été inspiré par les preuves dans la littérature que l'IL-32 présente des effets antiviraux. Nous avons exploré d'autres cytokines et facteurs qui modulent l'expression de l'IL-32 dans les cellules épithéliales intestinales et leur impact sur la remontée du VIH dans les cellules T CD4+ des personnes avec VIH traités par thérapie antirétrovirale. Nos résultats indiquent que l'IL-22 et le récepteur nucléaire PPARγ peuvent réguler à la hausse l'expression de l'IL-32 et réduire la réplication du VIH. Cependant, l'IL-26 a montré des effets antiviraux sans affecter la capacité des IEC à exprimer l'IL-32. Enfin, l'inactivation de l'IL-32 dans les cellules épithéliales intestinales par CRISPR/Cas9 n'a pas affecté leur capacité à promouvoir la réactivation du réservoir de VIH. Ainsi, nos résultats soutiennent un modèle dans lequel l'IL-32 exprimé par les cellules épithéliales intestinales contribue à la dérégulation immunitaire et à l'inflammation, plutôt qu'à des réponses antivirales au niveau de la barrière muqueuse.
Le troisième projet a examiné les implications systémiques de l'inflammation chronique et de la dérégulation immunitaire chez les personnes avec VIH traités par thérapie antirétrovirale, reliant ces conditions au risque des maladies cardiovasculaires. Nos résultats révèlent la présence atypique de cellules épithéliales CD326+ à des fréquences relativement élevées dans le sang périphérique des personnes avec VIH, la recirculation dérégulée des cellules intestinales exhibant un phénotype de cellules résidentes tissulaires, ainsi qu’une sous-population de cellules T CD4+ exprimant le marqueur de cellules épithéliales CD326. De plus, nous avons observé que la fréquence d'un sous-groupe de cellules T CD4+, exprimant le marqueur Th17 CCR6 et démunis de la molécule de homing intestinal Itgβ7, était fortement associée à un risque accru de maladie cardiovasculaire, suggérant un lien direct entre les altérations immunitaires et les maladies cardiovasculaires dans l'infection par le VIH traitée par thérapie antirétrovirale. Cette dernière partie de ma thèse souligne la nécessité de mener des études plus ciblées sur des traitements qui vont au-delà de la suppression virale efficace pour aborder la dérégulation immunitaire et réduire l'incidence des maladies cardiovasculaires, améliorant ainsi la qualité de vie d'une communauté vieillissante de personnes avec VIH. / Human immunodeficiency virus type 1 (HIV-1) has claimed around 40.4 million lives worldwide. Despite advancements in antiretroviral therapy (ART), which have transformed the landscape of HIV epidemiology, the virus continues to pose a significant health challenge worldwide, evidenced by approximately 1.3 million new cases by the end of 2022, bringing the total to 39 million people with HIV (PWH) nowadays. HIV-1's harmful effects extend beyond the development of AIDS, notably exacerbating chronic inflammation and elevating the risk of cardiovascular diseases (CVD) among infected individuals. While ART has been significant in managing the virus on a global scale, the ongoing absence of a definitive cure and the persistent issues related to immune system dysregulation and inflammation highlight the critical need for continued research.
This dissertation investigated the relationship between HIV-1 infection, gut mucosal immune dysregulation, cytokine expression, and systemic inflammation, with a focus on CVD risk in aging individuals receiving ART. Specifically, the complex immune dynamics involving intestinal epithelial cells (IEC), Th17 cells, the pro-inflammatory cytokine Interleukin (IL)-32 within the gut-associated lymphoid tissues (GALT), and the existence of circulating gut cells were evaluated. We aimed to address how HIV-1 perpetuates chronic inflammation and identify new targets for potential interventions to mitigate the long-term health consequences for PWH.
The first project focused on monitoring the expression of IL-32 isoforms in the colon of ART-treated PWH compared to uninfected individuals and associated IL-32β with a decrease in Th17 hallmark cytokine IL-17A expression. This imbalance is proposed as a significant factor contributing to inflammation and potential compromise of gut barrier integrity. The research highlights the role of IL-32 in promoting inflammation through its interaction with other pro-inflammatory cytokines, which could lead to tissue damage and elevate CVD risk.
The second project was inspired by the evidence in the literature that IL-32 exhibit antiviral effects and explored additional cytokines and factors that modulate IL-32 expression within IECs and their impact on HIV outgrowth in CD4+ T-cells of ART-treated PWH. Our findings indicate that IL-22 and the nuclear receptor PPARγ can upregulate IL-32 expression and reduce HIV outgrowth. However, IL-26 exhibited antiviral effects without affecting the capacity of IEC to express IL-32. Finally, CRISPR/Cas9-mediated IL-32 knockout in IEC did not affect IEC’s capacity to promote HIV reservoir reactivation. Thus, our results support a model in which IL-32 expressed by IEC contributes to immune dysregulation and inflammation, rather than antiviral responses at mucosal barrier level.
The third project delved into the systemic implications of chronic inflammation and immune dysregulation in PWH, linking these conditions to CVD risk. Our results reveal the atypical presence at relatively high frequencies in the peripheral blood of ART-treated PWH of CD326+ EC, together with dysregulated gut-homing, or resident immune cell phenotypes, as well as a subpopulation of CD4+ T-cells expressing the IEC marker CD326. Also, we observed that the frequency of a subset of CD4+ T-cells, expressing the Th17 marker CCR6 and lacking the gut-homing molecule Itg7, was strongly associated with a higher CVD risk, suggesting a direct connection between immune alterations and CVD in ART-treated HIV infection. This final part of my thesis stresses the need for more focused studies of treatments that extend beyond effective viral suppression to address immune dysregulation and reduce CVD incidence, thereby improving the quality of life of an aging community of PWH.
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