Distribution and Expression of Visfatin-Positive Cells in the Spleen of Lipopolysaccharide-Stimulated Piglets

The histological changes in the spleen and the immunohistochemical expression of visfatin in lipopolysaccharidestimulated piglets are reported to examine the relation between visfatin and inflammation. The results are as follows: (1) After LPS treated, the spleen displayed thicker capsules and trabecula, the thinner periarterial lymphatic sheath, and the more expandable splenic sinusoid, with an increase in the number of splenic nodules, lymphocytes, ellipsoids of the marginal zone, red blood cells and macrophagocytes. (2) Visfatinpositive cells were mainly distributed in the red pulp of the spleen, with less in splenic nodules and periarterial lymphatic sheath. In the LPStreated group, the signal intensity and quantity of the visfatin-positive cells were significantly higher in the red pulp and the ellipsoids of the spleen (P<0.01), whereas lower in the periarterial lymphatic sheath. These results indicate that LPS stimulation induces inflammation, causing the histological changes of the piglet spleen and activating humoral immune response. Moreover, variation of visfatin in the spleen suggests that lymphocytes and macrophages are the potent source of visfatin which participates in the humoral immune response in the inflammation.