Levels of IL-18, sCD14, CCL2, CXCL8 and CXCL10 in tubercular immune

reconstitution inflammatory syndrome in a North Indian population

Manoj Kumar1, Patricia Price3, Manisha Jain1, Ben Oliver3, Amitabh Kumar2, Upasna Agrawal2, Sarman Singh1

1. Department of Laboratory Medicine, All India Institute of Medical Sciences, India. 2. LRS Institute of TB & Respiratory Diseases, New Delhi, India.

3. School of Pathology & Laboratory Medicine, University of Western Australia, Australia

Abstract Number: 11497 (WEPDA204)

IntroductionSome HIV-TB co-infected patients on ATT develop worsening of signs and symptoms of tuberculosis during the initial months of ART. This is termed paradoxical Immune Reconstitution Inflammatory Syndrome (IRIS).

IRIS frequency is variable and its immunopathogenesis is poorly understood.

Objectives To determine the frequency, risk factors and outcome of

mycobacterial IRIS in Indian patients co-infected with HIV/TB and receiving ATT and ART.

ELISA studies of cytokines, chemokines and antibodies relevant to IRIS

Material and Methods

Recruitment of Patients, n=62 (Aug 2007-April

2009)

Host genetic polymorphism study (now

underway)

Immunological assays using ELISA

Demographics and Baseline Characteristics of patients

62 patients were followed for 6 months

IRIS(n=19)

Non-IRIS (n=43)

pa

PTB 5 (26%) 18 (42%) 0.20EPTB 12 (63%) 16 (37%) 0.20PTB + EPTB 2 (11%) 9 (21%) 0.40% of cohort 31% 69%

Patient age (years) 36 (25-50) 35 (18-65) 0.69Male 16 (84%) 34 (79%) 0.78Died 7 (37%)b 6 (14%) 0.09CD4 T-cells/ul at start of ART 78 (14-189) 100 (2-198) 0.56CD4 T-cells/ul at 6 months 181 (46-582) 125 (59-664) 0.13ATT before ART (days) 28 (5-117) 27 (7-255) 0.55ART before IRIS (days) 17 (5-153) NA -

a Mann Whitney U test (continuous variables) or Fisher’s test (categorical variables) b 4 patients with TB Meningitis as IRD, all died; NA, not applicable

sCD14 plasma levels were marginally higher at the IRIS event compared to baseline.Levels did not change in patients without IRIS.

Elevated IL-18 and sCD14 suggest monocytes contribute to IRIS

Plasma IL-18 levels were higher at the IRIS event than baseline (p=0.05).

Levels did not change in Non-IRIS patients.

IRIS

Week

0

IRIS

Time

Non-IR

IS w

eek 0

Non-IR

IS w

eek4

0

5000

10000

15000

sCD

14 C

once

ntra

tion

(pg/

ml)

0

10000

20000

30000

IL-1

8 C

once

ntra

tion

(pg/

ml)

p = 0.73p = 0.05p = 0.23 p = 0.47

p = 0.54p = 0.06p = 0.14 p = 0.32

Low plasma levels of CCL2 and CXCL8 may predispose a patient to IRIS

CCL2 levels were lower in IRIS patients than non-IRIS patients at baseline (p=0.03).

CCL2 levels did not rise on ART in any patients.

CXCL8 levels were marginally lower in IRIS patients at baseline

CXCL8 levels increased on ART in non-IRIS patients (p=0.02).

10

100

1000

10000

100000p = 0.08

p = 0.02p = 0.15p = 0.13

CXCL

8 C

once

ntra

tion

(pg/

ml)

p = 0.23 p = 0.63p = 0.03 p =0.34

IRIS

Week 0

IRIS

Time

Non-IR

IS wee

k 0

Non-IR

IS wee

k4

1

10

100

1000

10000

100000

CCL2

Co

ncen

trat

ion

(pg/

ml)

Low plasma levels of CXCL10 also may predispose a patient to IRIS

0

2000

4000

6000

8000

100001000015000200002500030000

CX

CL

10 C

once

ntra

tion

(pg/

ml)

p = 0.43p =0.05p = 0.91 p = 0.08

Rise in CXCL10 levels was found in both IRIS and non-IRIS patients on therapy. But baseline levels predicted IRIS (p=0.05).

Discussion & Conclusions

Paradoxical TB IRIS is relatively common, affecting 31% of patients in a TB clinic in India.

IRIS and non-IRIS patients were similar in age, baseline CD4 T-cell counts, CD4 T-cell recovery and duration of ATT before ART.

The increased levels of IL-18 and sCD14 in paradoxical TB IRIS suggest a role for the monocyte response to bacterial motifs.

Low levels of chemokines at baseline may also promote paradoxical TB IRIS – perhaps by impairing mycobacterial clearance. These molecules should be investigated as prognostic markers.

AcknowledgementAIIMS, New Delhi,

IndiaProf. Sarman Singh

Manisha Jain

LRS, New Delhi, IndiaDr. Upasna AgrawalDr. Amitabh Kumar

Dr. Jyoti SharmaMrs. Komal Sharma

Mrs. MeenakshiArjun & SatPal

UWA, Perth, Australia

Prof. Patricia Price Dr. Martyn French

Ben Oliver Jacquita AffendiSara Tanskovic

I would like to express my gratitude to all lab colleagues & all my patients who participated in the study.

Left to right: Dr. Amitabh Kumar, Prof. Patricia Price, Prof. Sarman Singh, Mr. Manoj Kumar, Dr. Upasna Agrawal