Leishmaniasis is a parasitic infection caused by a protozoan from the
Trypanosomatidae family, genus Leishmania. A well established mouse model of
visceral leismaniasis disease exists using a strain (BALB/C) of mice susceptible to
the disease. An experiment was performed in order to examine the effects of an antiIL-10
immunomodulatory agent on cytokine production by T cells in a mouse model
of Leismaniasis. L. major promastigotes were injected into the ears of BALB/c mice.
After 4 weeks T cells were isolated from the lymph nodes and cultured for 48 hours
in the presence of 5 μg/mL of soluble Leishmania antigen (SLA). Supernatants from
these cultures were harvested and ELISA experiments performed to investigate IFNg
and IL-4 production by the T cells. Following infection, a group of mice were treated
with an anti-IL-10 immunomodulatory agent prior to isolation and culture of T cells.
For comparison, two groups of control mice were used: one group was uninfected
and untreated (no immunomodulatory agent) and the other was uninfected but
treated with the anti-IL-10 agent. Details of the samples can be found below.
Following infection, L.major infected mice developed skin lesions and showed a high
worm burden at the site of infection. The anti-IL-10 treated mice showed reduced
symptoms and reduced worm burden. Both groups of control mice were healthy.
You should first analyse the data you are provided with to determine the amount of IFNg and IL-4 produced by each of the four experimental samples (A-D). a) You should plot the standard curve of the two ELISA experiments on a graph using an appropriate analysis package (eg. Sigmaplot, etc) – ensure graphs are presented and labelled appropriately. b) You should present the results of your analysis of the experimental samples in a separate graph. c) You should describe your results (500 words maximum). Remember to include a description of what your sample and treatment groups did in comparison to controls. You should comment on what the sensitivity of the two ELISA experiments was and how significant, reliable and reproducible your results are. d) You should then give a brief discussion and conclusion for your findings (500 words maximum). Why were these two cytokines measured? What can they tell us about how the body fights the infection? Why might treatment with the anti-IL-10 agent effect the production of IFNg and IL-4 by T cells and why might this effect the health of the mice. Finally, can you find any research literature that supports these conclusions in human Leismaniasis infection?