ENCONTRO INFECÇÕES E TB GOIANIA 2012

Apresentação em tema: "ENCONTRO INFECÇÕES E TB GOIANIA 2012"— Transcrição da apresentação:

1 ENCONTRO INFECÇÕES E TB GOIANIA 2012
MECANISMOS IMUNOLÓGICOS DAS INFECÇÕES RESPIRATÓRIAS E TB José Roberto Lapa e Silva Faculdade de Medicina Universidade Federal do Rio de Janeiro

2 DELINEAMENTO Relevância do tema
Resposta imune inflamatória na porta de entrada - Papel dos neutrófilos Resposta imune na infecção latente - Papel do granuloma Resposta imune na doença ativa - Imunossupressão na TB ativa Conclusões

3 RELEVÂNCIA DA PESQUISA EM IMUNOLOGIA DA TB

4 A transmissão aerógena da tuberculose
Raios solares ultra-violetas Matam bacilos Partículas levitantes Partículas infectantes CONTATO FOCO (+++) Partículas maiores que se depositam Fernando Fiuza de Mello

5 Em 70% das pessoas que inalam bacilos, eles
são detidos na porta de entrada por barreiras e imunidade inata A depuração mucociliar é importante mecanismoss de defesa contra a TB Células e substâncias contribuem para o controle da infecção

6 Fagocitose pelo macrófago alveolar
Infecção: uma transmissão bem sucedida Nidação do bacilo no alvéolo Crescimento livre Fagocitose pelo macrófago alveolar Fernando Fiuza de Mello

7 Migração de monócito-macrófagos
Maior atividade inicial contra o bacilo Diseminação hematogênica intra-monócito Alvéolo Capilar Macrófago Polimorfo Monócito Linfócito Fernando Fiuza de Mello

8 Neutrófilos participam da fase inicial do
estabelecimento da infecção por TB Ectossomas são vesículas dos neutrófilos que suprimem a ação micobactericida dos macs (Duarte TA, Tuberculosis 2012)

9 bacilo intra macrófago
Fagocitose e multiplicação bacilar intra-macrófago Rompimento do fagossoma e do lisofagosoma Lisossoma Fagocitose Fagossoma Lisofagossoma (de fusão) Crescimento livre do bacilo intra macrófago Atividade bacilar bloqueando a fusão fagossoma+lisossoma e novas fagocitoses Macrófago Fernando Fiuza de Mello

10 4 Imunidade na TB: Sinalização MHC1 Sinalização MHC2 L.T-CD3/8
Macrófago 4 L.T-CD8 Ativação L.T-CD4 Th 0 L.Tm Th 1 Th 2 Diferenciação Ativação Grânulos bactericidas bacteriostáticos Ativação do macrófago produção de peróxidos limitação das lesões IL2 + g IT IL8 e outras  TFN -a -  das lesões IL4, 5,12 e outras Atividade citotóxica e ação de grânulos

11 Modelo esquemático do granuloma
Necrose caseosa Capilar Ptose vascular Macrófago Célula de Langhans Linfócito auxiliar Polimorfo nuclear modulador Fernando Fiuza de Mello

12 Granulomas tuberculosos com necrose caseosa (HE)
José Roberto Lapa e Silva

13 Células epitelióides formando paliçada em torno do granuloma (IPX, RFD9)
José Roberto Lapa e Silva

14 Células dendríticas presentes no infiltrado em torno do granuloma (IPX, RFD1)
José Roberto Lapa e Silva

15 DIFERENTES ESTÁGIOS DO GRANULOMA
Reece & Kaufmann. Curr Opin Microbiol 2012

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18 HYPOTHESIS Active TB is marked by a relative immunodepression in the affected host Despite the increased expression of defense molecules, some individuals evolve to uncontrolled disease Possible explanation: increased production of deactivating cytokines in the lungs, such as IL-10 or TGF-beta

19 STRATEGY Use of bronchoalveolar lavages to investigate lung immune response during the development of active TB Investigation of phenotypic changes in lung cells, production of cytokines, expression of cytokine genes, enzymes and receptors during the development of active disease

20 Co-expression of activating and deactivating cytokines in BAL lysates
Bonecini-Almeida MG et al. Inf. Immun. 2004; 72:2628

21 Presence of biologically active TGF-b ligand in
BAL supernatants Bonecini-Almeida MG et al. Inf. Immun. 2004; 72:2628

22 Presence of cytokines in BAL supernatants
Bonecini-Almeida MG et al. Inf. Immun. 2004; 72:2628

23 Correlation Between CFP32 (Rv0577) and IL-10 in
Sputum of Patients with Active Pulmonary Tb R2 = 0.58 Huard RC et al. Inf. Immun. 2003; 71:8871

24 STRATEGY Collection of induced sputum from bacteriologically confirmed TB patients at the time of diagnosis and at the following times during treatment: 15 DAYS 30 DAYS 60 DAYS 180 DAYS

25 Host immune markers for TB
We compared cases of TB (n=30), other lung diseases/OLD (n=11), health workers/HCW (n=16) at time of diagnosis; TB cases were followed at 15, 30, 60, and 180 days of treatment; Cell pellets of induced sputum were lysed, mRNA extracted, and real-time PCR performed; Gene expression relative to GAPDH for each mediator was established. An.

26 Host immune markers for TB
The following set of genes were evaluated: - Genes that impair Th-1 immunity: IL-10, TGFβ-RI and II, IRAK-M, SOCS 1 and 3, IL1Rn, IDO - Genes that promote Th-1 immunity: IFN-γ,IL-12-p35 and p40, IL-23-p19, TNF-α, NEMO - Genes that affect both Th-1 and Th-2 responses: CD80, CD86, TLR2 An.

27 Host Mediators as Surrogate Markers for TB Diagnosis and Response to Anti-TB Treatment
Almeida et al. J Immunol 2009

28 PROTEIN EXPRESSION IN SPUTUM SUPS IN TB AND CONTROL SUBJECTS
Almeida et al. J Immunol 2009

29 Sumário dos achados Casos de TB expressaram > níveis de mediadores que se contrapõem à resposta tipo Th1 Altos níveis de mediadores intra (SOCS e IRAK-M) e extracelulares (IL-10, , IDO, etc.) que suprimem a resposta imune Estes mediadores são uma resposta direta ao Mtb, pois diminuem muito aos 30 D de tratamento. Almeida et al. J Immunol 2009

30 PROPOSED SCHEMATIC VIEW OF IMMUNE REGULATION IN TB
Ho & Lapa e Silva. Discov Med 2010

31 Hypothesis High levels of IL-10 in the lungs of M.tb. infected subjects could facilitate the development of active disease and recurrence of TB. Aim To investigate the levels of IL-10 and IFN-gamma in the lungs at TB diagnosis and during anti-TB chemotherapy and to correlate these levels to relapse rates over a long follow-up period In the present work, we pursued the hypothesis that high levels of IL-10 etc. To answer this question we designed a longitudinal study in which TB patients were evaluated at the time of diagnosis, during and after TB treatment and sputum samples collected at these time points and the patients were followed for over five years. Lago PM et al. Int J Tuberc Lung Dis 2012

32 Results IL-10 and IFN-gamma were both present in the lungs of TB patients at all time points but only IL-10 showed two patterns at the end of the treatment An Lago PM et al. Int J Tuberc Lung Dis 2012

33 TWO PATTERNS OF IL-10 IN TB PATIENTS IN SERIAL INDUCED SPUTUM
Pattern 1: IL-10 levels decreased until Day 60 of treatment and increased at Day 180 Pattern 2: IL-10 levels decreased until Day 60 of treatment and decreased even further at Day 180 Pattern 1 revealed a large increase in the levels of IL-10 at diagnosis and a decrease until T60 with a new increase at the end of treatment (T180). Pattern 2 showed a decrease from the IL-10 levels until T60 with a lower level at the end of treatment (T180). Red bars represent the median of IL-10 values for each time point. Limit of detection 5 pg/ml. Lago PM et al. Int J Tuberc Lung Dis 2012

34 TB recurrence and the two IL-10 patterns
20 patients had a follow up of months: six had other TB episodes and 14 didn’t; Out of the six cases with TB recurrence, - FIve had Pattern 1 - One had Pattern 2 [OR: 30,0 (CI 95% = 2, ,3), p= 0,0072 (Fisher’s exact test)]; 20 patients had a follow up of months: six had other TB episodes and 14 didn’t; Out of the six cases with TB recurrence, five had Pattern 1 versus one with Pattern 2 with a p value of less than 0,01; The six TB cases with recurrence had a total of 15 episodes of TB, including the one that had serial sputum collection. All episodes were treated with standard Rifampin, Isoniazid and Pyrazinamide for six months. At the last visit, all were well and the chest X-R had limited fibrosis compatible with TB sequelae. Lago PM et al. Int J Tuberc Lung Dis 2012

35 CONCLUSÕES A TB latente (LTBI) é um dos maiores desafios da saúde pública mundial (reservatório de 2 bi de pessoas, do qual sairão os casos ativos) Os mecanismos de transição da LTBI para TB ativa são largamente desconhecidos A imunossupressão própria da TB ativa resulta em maior morbidade e mortalidade O estudo da imunopatogenia da TB ajudará a encontrar respostas para estas questões