Correlation of parasitic load with interleukin-4 response in patients with cutaneous leishmaniasis due toLeishmania tropica

Abstract

We have established the association between parasite burden and localized immune response in patients with cutaneous leishmaniasis (CL) caused by Leishmania tropica. Real-time PCR was used to measure parasitic load in tissue lesions of CL patients at the pretreatment (n=26) and at the post-treatment stage (n=10). Leishmania tropica was detected in all CL lesions with a mean value of 118 357 parasites g(-1) of dermal tissue. Following treatment, only one out of 10 patients showed residual parasites (100 parasites g(-1) tissue). Parasite load was high (mean, 306 000 parasites g(-1) tissue) in acute infections (early lesions) and low (mean, 1081 parasites g(-1) tissue) in chronic infections (late lesions). Intralesional transcripts of interferon-gamma, tumour necrosis factor-alpha, interleukin-1beta (IL-1beta), IL-8, IL-10 and IL-4 were investigated in early lesions (<or=2 months, n=14) and late lesions (>2 months, n=15) by reverse transcriptase-PCR, where IL-4 was found to be significantly upregulated in early lesions (P<0.02). Further, the levels of parasite burden and IL-4 were distinctly correlated in various clinical forms of CL. Other cytokines were at comparable levels in early/late lesions and in different clinical forms. Upregulation of IL-4 was correlated with a higher parasite burden in early lesions of CL, which may be involved in the pathogenesis of CL by inhibiting a protective immune response.

Development of a rapid loop-mediated isothermal amplification assay for diagnosis and assessment of cure of Leishmania infection

“…Thus, with the sensitivity comparable to Q-PCR (both detects up to 1 fg DNA), LAMP assay can undoubtedly be volunteered as an efficient tool for diagnosis of VL and PKDL as it is simpler, faster and easy to perform. In addition, LAMP assay efficiently detected parasite DNA in the same VL ( n  = 2/20) and PKDL ( n  = 2/21) cases at post-treatment stage which were detected positive for parasite DNA by Q-PCR as reported earlier [21, 39]. Close agreement in the results of LAMP and Q-PCR assays at post-treatment stage highlights the utility of LAMP assay as a point-of-care test for assessment of cure of VL and PKDL cases, though a detailed evaluation of the assay in a large number the patients is required to appraise its prognostic efficacy.…”

“…The patients with characteristic symptoms of VL (fever, hepatosplenomegaly, anemia and leucopenia) and PKDL (on clinico-histopathological observations) who were positive by rK39 strip test were included in this study. All the cases were confirmed by Q-PCR assay [21]. Peripheral blood (0.5 ml from 66 cases) and bone marrow aspirate BMA (100 μl from 15 cases) were collected from VL patients while tissue biopsy (4-6 mm punch biopsy from 67 cases) were collected from PKDL patients at pre-treatment stage.…”

“…SYBR Green I based Leishmania genus specific Q-PCR was performed using F3 and B3 primers using the reaction conditions as described previously [21]. A 10 μl of the PCR reaction was performed, consisting of 1X SYBR Green I PCR Master mix (Applied Biosystems, USA), 5 pmol forward primer F3, 5 pmol reverse primer B3, and 1 μl sample DNA.…”

Regulatory IgDhi B Cells Suppress T Cell Function via IL-10 and PD-L1 during Progressive Visceral Leishmaniasis

“…IL-4 production is a hallmark of both cutaneous and visceral leishmaniasis implicated in supporting logarithmic parasite growth and disease progression (35, 36). Murine regulatory B cells were shown to produce IL-4 in conjunction with IL-10 after stimulation with immune regulatory receptor TIM-1 (37).…”

Clinical Presentation of Cutaneous Leishmaniasis caused by <b><i>Leishmania major</i></b>

“…In 1998, Louzir et al [44] reported that the unfavorable clinical outcome of CL was positively associated with high IL-10, IL-12, and IFN-γ mRNA expression. Also, Kumar et al [45] demonstrated that the levels of parasite burden and IL-4 were distinctly correlated in various clinical forms of CL due to L. tropica .…”