Immunology Platform 2012

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Prepared by:

Polidy Pean, Head, Immunology Platform

Institut Pasteur du Cambodge, 5, Bvd. Monivong BP 983 - Phnom Penh, Royaume du Cambodge

Immunology

Platform

2012

The scientific activity report of Immunology

Platform of the Institut Pasteur du Cambodge for

the period January 1st to December 31st, 2012.

Scientific

activity

report

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Annual Report ANRS sites in Cambodia 2011-2012

Research team

Team leader: Polidy Pean, MD, PhD Technical staff : Ratana Meng

Introduction

Cambodia is one of the countries with the highest prevalence of HIV and tuberculosis (TB) infections. An estimation of 64% and 0.7% Cambodian people were infected by TB and HIV-1 respectively, and HIV-1/TB co-infection has increased annually, from 2.5% in 1995 to 10% in 2005. The effective treatments of both infections have reduced the mortality and morbidity. However, simultaneous treatments of both infections were complicated by many problems such as drug toxicity, drug resistance and tuberculosis associated immune reconstitution inflammatory syndrome (TB-IRIS). TB-IRIS occurs in 10 to 25% of patients who were treated with antiretroviral and anti tubercular drugs. It could be an obstacle for antiretroviral therapy management and may have an impact on immune reconstitution in severely immunocompromized patients. Diagnosis of TB-IRIS is very difficult and is always a clinical diagnosis of exclusion. Thus, the understanding of mechanism of TB-IRIS, the impact of TB-IRIS on immune reconstitution and identification of its related biomarkers for prediction and diagnosis of this syndrome is very important.

Research Activities in 2011-2012

In collaboration with Dr Daniel Scott Algara and his colleagues (Pasteur Institute in Paris) and CAMELIA (Cambodian Early versus Late Introduction of Antiretroviral Drugs) clinical trial team and with the grant support from ANRS 12153, we investigated the implication of innate immunity of NK cells in the onset of IRIS in HIV-infected patients with TB to identify predictive markers of IRIS. As the results, 128 HIV-HIV-infected patients with TB from the CAMELIA trial were enrolled in the study. Thirty-seven of the 128 patients developed IRIS. At inclusion, patients had low CD4 cell counts (27cells/mm3) and high plasma viral load (5.76 and 5.50 log/mL in IRIS and non-IRIS patients, respectively). At baseline, NK-cell degranulation capacity was significantly higher in

ANRS 12153 project: “Camelia Paradoxical Reaction Immune NK cells study (CAPRI-NK)”

Principal Investigators: Dr Daniel Scott-Algara (IP Paris) and Dr Eric Nerrienet (IP Cambodia)

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IRIS patients than in non-IRIS patients (9.6% vs 6.38%, P <0.005). At IRIS onset, degranulation capacity did not differ between patients, whereas activating receptor expression was lower in IRIS patients. Patients with degranulation levels > 10.84% had a higher risk of IRIS (P = 0.002 by log-rank test). Degranulation level at baseline was the most important IRIS predictor (hazard ratio = 4.41; 95% confidence interval, 1.60-12.16). These results have been published in Blood on april 2012.

We also investigated NK cell reconstitution in HIV/TB co-infection (IRIS and non-IRIS patients) at 8 weeks of cART in comparison with HIV mono-infected patients at 6 weeks of cART. As result, we found that NK cell degranulation was similar in TB-IRIS and non TB-IRIS patients following early cART (6 weeks). A trend towards a decrease of total degranulation capacity from baseline to 6 weeks of cART was observed in TB-IRIS and a slightly increase in non TB-IRIS when they were compared to baseline value. By contrast, the total degranulation capacity of NK cell was significantly increased in HIV mono infected patients at 8 weeks of cART (p< 0.001). When delta values of total degranulation were compared, significant differences were found between HIV mono infected patients and IRIS and non IRIS patients (p=0.004 and p<0.001, respectively). We did not detect any increase of the total IFN- secretion by NK cell after target stimulation after 6 weeks of cART in TB/HIV co-infected patients and this is in contrast to those observed in HIV infection alone. In addition, the evolution of CD107a+ IFN-+ NK cells from baseline to 6/8 weeks of cART has also been found to be low in both TB-IRIS and non-TB-IRIS group, whereas those in HIV treated patients was increased. Globally, we did not find any difference in term of evolution of NK cell degranulation activity and/or IFN- secretion between TB-IRIS and non TB-IRIS patients during the follow up.

A manuscript of those results is in preparation.

Research Achievements and Outcomes.

Pean P, Nerrienet E, Madec Y, et al. Natural killer cell degranulation capacity predicts early onset of the immune reconstitution inflammatory syndrome (IRIS) in HIV-infected patients with tuberculosis. Blood;

119(14):3315-20.

Training: One Cambodian PhD student ( Mr Pean Polidy) has successfully defended his thesis on this project in December 2011

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This study is supported by ANRS 12164 and US NIH (for a supplemented grant). In collaboration with Professor Anne Goldfeld’s team (Program in Cellular and Molecular Medicine, Children’s Hospital-Boston, USA) and CAMELIA clinical trial team, we investigated the immunological basis of TB-IRIS in patients enrolled in CAMELIA clinical trial and its impact on T cell reconstitution. Our aim is to examine the evolution of T cell compartment in TB/HIV co-infected patients (CD4+ T cell counts <200/mm3) enrolled in the trial. We compared the results from patients who developed TB-IRIS within 3 weeks after initiating cART to those who did not develop TB-IRIS (non TB-IRIS). Whole blood T cells immunophenotypes and serum cytokines from 36 TB-IRIS and 104 non-TB-IRIS patients were evaluated prior to ART and at timepoints up to 32 weeks post-ART initiation. As the result, in patients who developed TB-IRIS there were significantly higher proportions of activated HLA-DR+CD4+ (p=0.005) and CCR5+CD4+ (p<0.0001) T cells. There were similar levels of activated CD38+CD8+ and regulatory CD4+ T (CD25+/CD127lo) cells in the two groups at cART initiation and at ensuing timepoints. While CD62L-CD45RA- CD4+ effector memory (EM) T cell proportions continued to increase after the TB-IRIS event up to week 32, while in non TB-IRIS patients CD4+EM cell reconstitution stabilized by week 8 post-ART (p=0.005). Within the first two weeks post-ART, HLA-DR+CD4+ (p=0.0023) and CCR5+CD4+ (p=0.0035) T cell proportions, and serum levels of IL-1 (p=0.026) and IL-6 (p=0.0066), increased at significantly faster rates in TB-IRIS patients as compared to non TB-IRIS patients. In conclusion, global CD4+ T cell activation, elevated CCR5+CD4+ T cell levels and viral load were significantly higher at ART initiation in TB-IRIS patients. The increase in IL-1 and IL-6 after ART initiation in TB-IRIS patients with increased viral antigen load may drive the elevated CD4+ T cell activation in TB-IRIS patient.

Research Achievements and Outcomes.

Scientific communication: an abstract on “Impact of Tuberculosis-Associated IRIS on T Cell Activation and Reconstitution in Highly Immunosuppressed HIV/TB Co-Infected Patients Starting ART “ has accepted for discussion and poster presentation in 20th CROI 2013 (US-Atalanta). (Abstract No S-186)

Publication: The manuscript of this result is in preparation.

Training: One Cambodian PhD student (Mr Pean Polidy) has successfully defended his thesis on this project on december 2011

-CAMELIA (TB/HIV) patients

:

blood collected at weeks 2, 4, 8, 10, 14, and 34

post-TB therapy initiation. Blood is also collected at the time of PR diagnosis.

-TB patients

: blood collected at weeks 2, 4, 8, 10, 14 and 34 post-TB therapy

initiation.

-HIV patients

: blood collected at the time of HAART initiation, and at weeks 6,

12 and 32.

-Healthy controls

: blood collected at time of enrollment and at 6 months.

ANRS 12164 project“Camelia Paradoxical Reaction Immune T cells study (CAPRI-T)”

Principal investigators: Pr Anne Goldfed ( Boston USA), Dr Pean Polidy ( IP Cambodia)

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5 | P a g e Principal investigators: Dr Olivier Marcy (France), Dr Ung Vibol (Cambodia. Regional Project Manager: Dr Laurence Borand - Country project Manager: Mrs Pheng Phearavin

Collaborators: National Pediatric hospital (Phnom Penh) and Angkor Hospital for Children (Siem Reap), Epidemiology and Public Health Unit, Clinical laboratory Unit, Immunology Platform IP Cambodia

Childhood tuberculosis (TB) accounts for 11% of the total 9 million annual TB cases and is still not considered a public health priority in endemic countries. The difficulty of diagnosing TB in children is increased in case of HIV infection, in a situation of very high morbidity and mortality and major therapeutic and care issues. The tests currently available in developing countries as well as diagnostic approaches recommended by the national programs or WHO are not sufficiently sensitive and specific. Improved diagnostic criteria are imperative. The new immunological tests measuring the secretion of interferon-gamma (IGRAs) by lymphocytes activated by specific Mycobacterium tuberculosis (MTB) complex antigens are interesting alternatives to the tuberculin skin test (TST), but must be evaluated in immunocompromised children. Our aims is to evaluates the sensitivity, specificity, positive and negative predictive values of an in-vitro Interferon Gamma Release (IGRAs): the QuantiFERON®-TB Gold In-Tube, for the diagnosis of TB in HIV infected children and to compare the performances of two in-vitro IGRAs: the QuantiFERON®-TB Gold In-Tube and the T.SPOT-TB®, for the diagnosis of tuberculosis in HIV infected children in a sub-group of children (in Cambodia). This multicentric study is done in collaboration with Dr Nguyen Thi Ngoc Lan team (Microbiology Laboratory, Pham Ngoc Thach Hospital, Ho Chi Minh City Vietnam), Dr Guislaine Carcelain (Hôpital Pitié-Salpêtrière, Paris, France) and Epidemiology and Public Health Unit of IPC (Dr Laurence Borand) and with grant support from ANRS 12229. On November 30th, 2012, 84/120 suspected HIV/TB coinfected children were enrolled in Cambodia. The inclusion and data collection are ongoing.

ANRS 12 229 Study: “Improving diagnosis of Tuberculosis in HIV infected children in Asia (Cambodia, Vietnam) and in Africa (Burkina Faso, Cameroon) (PAANTHER 01)

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Perspective: Participation of the Platform of Immunology (Dr PEAN Polidy) and the HIV/Hepatitis

Unit (Mr NOUHIN Janin)

See Report NOUHIN Janin

Publication:

Pean P, Nerrienet E, Madec Y, et al. Natural killer cell degranulation capacity predicts early onset of the immune reconstitution inflammatory syndrome (IRIS) in HIV-infected patients with tuberculosis. Blood;

119(14):3315-20.

Scientific communication: an abstract on “Impact of Tuberculosis-Associated IRIS on T Cell Activation and Reconstitution in Highly Immunosuppressed HIV/TB Co-Infected Patients Starting ART “ has accepted for discussion and poster presentation in 20th CROI 2013 (US-Atalanta). (Abstract No S-186)

Impact of maternal HIV infection and feeding mode on the maturation of innate immunity and morbidity in infants in the context of the elimination of MTCT* of HIV-1 in Cambodia

(CAMENI)

Figure

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References

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