Quantification of parasite load in clinical samples of leishmaniasis patients: IL-10 level correlates with parasite load in visceral leishmaniasis.
A rapid and accurate method to detect and quantify Leishmania parasite is urgently needed to facilitate early diagnosis of leishmaniasis and monitoring of antileishmania therapy. In this study, real-time assay was applied to estimate parasite load in clinical samples of visceral leishmaniasis (VL) and post kala-azar dermal leishmaniasis (PKDL) patients. The mean parasite load in blood of VL patients (n = 31) was 8,372 parasites/ml, while the mean parasite load in bone marrow aspirate (BMA) was 194,962 parasites/million nucleated cells (n = 12). Parasite load was undetectable after treatment with amphotericin B (n = 9) in VL, while a residual parasite burden was detected in 2 of 6 patients following treatment with sodium antimony gluconate. Further, circulating levels of IFN-gamma, TNF-alpha, IL-10, IL-6, IL-4 and IL-2 were analysed in VL patients (n = 29) by Cytometric Bead Array to evaluate correlation with parasitic load. Interestingly, IL-10 levels correlated significantly with parasite load (r = 0.82, P<0.0001). The mean parasite load in dermal lesions of PKDL patients was 9,502 parasites/microg tissue DNA at pre-treatment stage (n = 25), with no detectable parasites after therapy (n = 5). Parasite burden was distinctly higher (P<0.0001) in nodular lesions (n = 12) (19,586 parasites/microg tissue DNA) compared to papular/macular lesions (n = 13, 193 parasites/microg tissue DNA). Further, chronic PKDL lesions showed significantly (P = 0.0166) higher parasite load in comparison with acute lesions. Results indicate that chronic, nodular cases constitute the major parasite reservoir for anthroponotic transmission. Our results establish that the high parasite load in VL is strongly correlated with a high level of IL-10, implicating IL-10 as a marker of disease severity. The assay is applicable for diagnosis as well as prognosis of both VL and PKDL, providing a simple molecular tool to monitor the efficacy of antileishmanial drugs or vaccines.
Verma
Sandeep
S
Institute of Pathology (ICMR), Safdarjung Hospital Campus, New Delhi, India.
Kumar
Rajesh
R
Katara
Gajendra Kumar
GK
Singh
Laishram Chandreshwor
LC
Negi
Narender Singh
NS
Ramesh
V
V
Salotra
Poonam
P
D015415:Biomarkers / Q000097:blood; D001769:Blood / Q000469:parasitology; D001853:Bone Marrow / Q000469:parasitology; D016054:DNA, Protozoan / Q000097:blood; D006801:Humans; D016753:Interleukin-10 / Q000097:blood*; D007891:Leishmania / Q000254:growth & development / Q000302:isolation & purification*; D007896:Leishmaniasis / Q000175:diagnosis*; D016773:Leishmaniasis, Cutaneous / Q000175:diagnosis; D007898:Leishmaniasis, Visceral / Q000175:diagnosis; D016133:Polymerase Chain Reaction; D012720:Severity of Illness Index
D015415:Biomarkers; D016054:DNA, Protozoan; D016753:Interleukin-10
J Clin Microbiol. 2001 Mar;39(3):849-54
11230394
Am J Trop Med Hyg. 2007 May;76(5):896-901
17488912
Cytokine. 1995 Oct;7(7):740-5
8580385
Infect Immun. 1995 Mar;63(3):1130-3
7868238
Infect Immun. 1994 Mar;62(3):1058-63
8112840
J Infect Dis. 2006 Oct 1;194(7):958-65
16960784
J Clin Microbiol. 2004 Mar;42(3):1214-9
15004078
J Clin Invest. 1993 Jul;92(1):324-9
8326000
Clin Immunol. 2006 Jun;119(3):339-45
16540374
Clin Exp Immunol. 2006 Oct;146(1):124-32
16968407
J Clin Microbiol. 2004 Nov;42(11):5249-55
15528722
J Immunol. 1995 Jul 15;155(2):722-9
7608550
J Immunol. 1994 Apr 1;152(7):3514-21
7908304
Rev Inst Med Trop Sao Paulo. 1998 Jan-Feb;40(1):31-4
9713135
Trans R Soc Trop Med Hyg. 2001 May-Jun;95(3):239-43
11490989
J Clin Microbiol. 2001 Jun;39(6):2065-71
11376036
Transfusion. 2008 Sep;48(9):1787-98
18564397
Trans R Soc Trop Med Hyg. 2000 Mar-Apr;94(2):200-4
10897369
J Immunol. 1993 Nov 15;151(10):5425-30
8228235
J Immunol. 1995 Mar 15;154(6):2668-77
7533180
Trop Med Int Health. 2007 Jul;12(7):848-51
17596251
Acta Trop. 2007 Sep;103(3):195-200
17662227
J Clin Microbiol. 2002 May;40(5):1666-9
11980939
J Exp Med. 2001 Nov 19;194(10):1497-506
11714756
FEMS Immunol Med Microbiol. 2009 Dec;57(3):239-46
19799628
J Immunol. 1992 Mar 15;148(6):1792-6
1541819
Trans R Soc Trop Med Hyg. 2002 Apr;96 Suppl 1:S179-83
12055835
Clin Infect Dis. 2000 Oct;31(4):1104-7
11049798
J Infect Dis. 1993 Oct;168(4):986-93
8376845
Clin Immunol Immunopathol. 1995 Oct;77(1):111-4
7554475
Cytokine. 2008 Nov;44(2):288-92
18842424
J Clin Microbiol. 1998 Jul;36(7):1989-95
9650950
J Immunol. 1991 Nov 1;147(9):3149-55
1833466
Trans R Soc Trop Med Hyg. 1993 Jan-Feb;87(1):94-6
8465412
Am J Trop Med Hyg. 2005 Dec;73(6):999-1004
16354801
J Parasitol. 2004 Oct;90(5):1150-4
15562617
Am J Trop Med Hyg. 2004 Nov;71(5):561-7
15569785
Br J Dermatol. 2000 Jul;143(1):136-43
10886148
J Clin Invest. 1993 Apr;91(4):1644-8
8097208
J Clin Pathol. 2003 Nov;56(11):840-3
14600129
Res Vet Sci. 2009 Aug;87(1):76-8
19178919
J Immunol. 1992 Feb 15;148(4):1143-8
1737931
Ann Trop Med Parasitol. 1992 Aug;86(4):355-9
1463355
Clin Diagn Lab Immunol. 2001 Jul;8(4):828-31
11427436
BMC Infect Dis. 2005 Dec 19;5:113
16364177
Vet Immunol Immunopathol. 2009 Apr 15;128(4):349-58
19124159
J Clin Microbiol. 2003 Nov;41(11):5080-4
14605142
J Mol Diagn. 2005 May;7(2):268-75
15858151
J Immunol. 1994 Oct 1;153(7):3135-40
8089491