I want to create an inflammatory model by using bacterial LPS (not sepsis). I am not sure which organ should i target (Lung, liver,Heart or any other).
I would suggest using the air pouch synovial inflammation model. It is fast, technically easy, and gives reproducible results. A simple pubmed search will give you some good references for the details, but the idea is that you inject air under the skin on the back of a mouse. After ~6-10 days an air pouch lining forms that bears a strong resemblance to human synovium. You can then inject your stimulus (LPS) into the air pouch and collect fluid at various time points. This is an acute model, so most of the action happens within the first 48 hours. Depending on the question that you are interested in, it might be of interest.
IP injections of LPS have been used to create models of systemic inflammation associated with behavioural depression - it can also be instilled directly into the bladder with similar effects:
Skelly, D.T., Hennessy, E., Dansereau, M.-A. & Cunningham, C. 2013. A systematic analysis of the peripheral and CNS effects of systemic LPS, IL-1Β, TNF-α and IL-6 challenges in C57BL/6 mice. Block, M.L., ed. PloS one, 8, e69123, 10.1371/journal.pone.0069123.
Takezawa, K., Kondo, M., Kiuchi, H., Soda, T., Takao, T., Miyagawa, Y., Tsujimura, A., Nonomura, N. & Shimada, S. 2014. Combination of bladder ultrasonography and novel cystometry method in mice reveals rapid decrease in bladder capacity and compliance in LPS-induced cystitis. American journal of physiology. Renal physiology, 307, F234–F241, 10.1152/ajprenal.00043.2014.
Swiergiel, A.H. & Dunn, A.J. 2007. Effects of interleukin-1beta and lipopolysaccharide on behavior of mice in the elevated plus-maze and open field tests. Pharmacology, biochemistry, and behavior, 86, 651–659, 10.1016/j.pbb.2007.02.010.
Liver cells uptake LPS very well. We work with human immortalized line HepG2. Mouse liver tissue uptake LPS as well. Heart could be use as a control, since it doesn't uptake LPS.
The quickest and easiest model system is simply systemic injection of LPS by whichever route is best for you. The i.p. route works well, then simply bleed the animals after 60-90minutes and assay the serum by ELISA or multiplex assay for TNFa initially. If you have access to the multiplex assay system you can measure TNFa, IL-1b, IL-6 and other mediators could also be added such as chemokines; IL-8 (KC) and MCP-1. You can then go on to do inflammation models in natural cavities, such as the peritoneum, or artificial ones, such as an air pouch, as has already been suggested. This adds a further possibility of looking at cell influx in addition to mediators. The cavities need to be washed out using PBS or similar and you can do total cell counting and differential cell counting on cytospins stained for nuclear differentiation. LPS should cause the influx of PMN's. Other systemic effects of LPS are on the liver with the induction of an acute phase response, iron, albumin, and SAP could be measured here amongst others.
Janet Dawson thank you for your suggestion.. i did it in serum but i wanted to know about the specific organ .. so i got from you as well as others that liver is a soft target ..
From answers provided I guess you are working with rodents. Other species may have specific organs which respond significantly to LPS. Ruminants, the lung is also involved. IV LPS produces significant pulmonary dysfunction. Low doses produced very measurable responses (physiologic, cytokine/chemokine, acute phase proteins) and they recover fine. Depends upon your model species