controlling Leishmaniasis using Th cells

1. PRESENTED BY
AYUSH JAIN
ROLL NO: 16
DEPARTMENT OF BIOTECNOLOGY, V.N.S.G.U

3. Abstract
Visceral leishmaniasis (VL) is the most distressing aliment among all type of leishmaniasis
caused by obligate intracellular protozoan parasite Leishmania donovani and L. Infantum.
Therefore it become rationale to develop a vaccine against this deadly disease.
The antigen identified was recombinant L. donovani S-adenosyl-L-homocysteine hydrolase
(rLdAdoHcy) which could be a great potential vaccine against Visceral leishmaniasis.
rLdAdoHcy generated perceptible DTH response and exerted considerably good prophylactic
efficacy(~70% inhibition) against L. donovani challenge. Which was conformed by increased
level of iNOS, IFNɣ, IL-12 and down regulation of IL4, IL-10 and TGF-.

4. Introduction
Therefore, ability to induce a pro-inflammatory response is essential for control of
leishmaniasis, in which the Th1 cytokines IL-2, IL-12, IFN-ɣ plays a important role, as
mediating the function of Macrophages.
Therefore, it suggest that any intervention that facilitates the shifting of the Th2 immune
response towards a Th1 immune response will have a significant impact on the treatment of VL.
Osborne, J. C., E. Khatamzas, A. Misbahuddin, R. Hart, A. Sivaramakrishnan and D. P. Breen (2016). 16(2): 139-141.

5. Hypothesis
rLdAdoHcy provides DTH and exert good prophylactic efficacy against L. donovani and
identified as Th1 stimulatory protein generating higher cellular up regulation of IL-12, IFN-ɣ
and down regulation of IL-10. Indicating the potentiality of rLdAdoHcy as a suitable vaccine
candidate against VL.

6. Result
Fig1:Cytokine production. (a) Interleukin
(IL)12, (b) interferon (IFN)-g and (c) IL-10 in
stimulated peripheral blood mononuclear cells
(PBMCs) of cured visceral leishmaniasis (VL)
patients and endemic controls in response to
recombinant Leishmania donovani S-adenosyl-
L-homocysteine hydrolase (rLdAdoHcy)
antigens; each data point represents one
individual.
The x-axis represents the group of individuals
(cured and endemic) and the y-axis corresponds
to the values of respective cytokine
concentrations in pg/ml. The mean concentration
of cytokine for each group is indicated by the
horizontal bars. Cytokine production was tested
in triplicate in two independent experiments and
the results were comparable. The lower
detection limits for various cytokines were as
follows: 51 pg/ml for IFN-g, 308 pg/ml for IL-
12 and 69 pg/ml for IL-10.

7. Fig 2: Prophylactic efficacy of recombinant
Leishmania donovani S-adenosyl
homocysteine hydrolase (rLdAdoHcy) in
hamsters against Leishmania donovani
challenges: body weight (a), spleen weight
(b) and liver weight (c) of hamsters in
mgrams (gm) on days 0, 45, 60, 90, 120 and
180 post-challenge (p.c.); parasite burden
(number of amastigotes per
1000 macrophage nuclei) in the dab smears
of spleen (d), liver (e) and bone marrow (f)
of hamsters on days 45, 60 and 90 p.c. As
the non-vaccinated challenged (infected
control), the bacillus Calmette–Guerin
(BCG)-vaccinated and challenged group
died after day 90 (D 90) of the study period,
their corresponding bars are not shown in
(d,e,f). Significance values indicate the
difference between the rLdAdoHcy-
vaccinated groups and infected group
(*P < 005; **P < 001; ***P < 0001).

8. Fig3:Analysis of mRNA expression profile
of recombinant Leishmania donovani S-
adenosyl-Lhomocysteine hydrolase
(rLdAdoHcy) 1 bacillus Calmette–Guerin-
vaccinated hamsters by quantitative real
time reverse transcription– polymerase
chain reaction (qRT–PCR). Splenic
inducible nitric oxide synthase (iNOS) (a)
and cytokines, interleukin (IL)212 (b),
interferon (IFN)-ɣ(c), tumour necrosis
factor (TNF)-(d), IL-4 (e), IL-10 (f) and
transforming growth factor (TGF)-b (g),
mRNA expression profile was assessed by
qRT–PCR in all the experimental groups of
hamsters on days 45 and 90 post-challenge
(p.c. Data are presented as means 6
standard deviation (s.d.) and are
representative of two independent
experiments with similar results.
Significance values indicate the difference
between the vaccinated and unvaccinated
infected control groups
(*P < 005; **P < 001;***P < 0001).

9. Fig4: Survival curve analysis of different experimental groups: survival of animals (six hamsters in each experimental group) was
observed up to day 180 post-challenge (p.c.). Significance values indicate the difference between the vaccinated and infected
(unvaccinated) control groups.

10. Conclusion
IL-10, a Th2 cytokine which promotes intracellular infection, was found to be suppresses
against recombinant protein in treated patient.
These results indicates strongly that rLdAdoHcy possesses a dominant Th1 stimulatory
property and thus can be potential vaccine.

11. Reference
Khare, P., A. K. Jaiswal, C. D. Tripathi, S. Sundar and A. Dube (2016). "Immunoprotective
responses of T helper type 1 stimulatory protein-S-adenosyl-L-homocysteine hydrolase against
experimental visceral leishmaniasis." Clin Exp Immunol 185(2): 165-179.
Osborne, J. C., E. Khatamzas, A. Misbahuddin, R. Hart, A. Sivaramakrishnan and D. P. Breen
(2016).