Efficacy of interleukin-6 in the induction of liver cell proliferation after hemi-hepatectomy: histopathologic and immunohistochemical study.

INTRODUCTION

The function of Interleukin-6 (IL-6) in the regenerative process is not fully understood. The aim was to show the IL-6 role in hepatocyte regeneration by identifying the proliferative rate of hepatocytes following partial hepatectomy.

MATERIAL AND

METHODS

Eighty male adult Sprague-Dawley rats were categorized into two equivalent groups (n = 40 rats); non-treated, and treated group with IL-6 of 35 µg/100 gm body weight according to lethality study for a four-day observation. Both groups were subjected to 70% hepatic resection. Liver specimens were taken for histo/immunohistochemical studies. Five measures were investigated histopathologically; binucleation, mitoses, thickening of the hepatic plate, ductular reaction, and presence of inflammatory cells. Ki-67 labeling index was evaluated using mouse anti-Ki-67 antibody.

RESULTS

In non-treated group; binucleation and multinucleation were noted in 12 cases (30%), bizarre cells with abnormal mitoses 16 cases (42%), and thickening of liver cell plate 18 cases (45%), in contrast to 32 (80%), 30 (75%) and 28 (70%), in treated group. Patches of inflammatory infiltrate were more marked in the treated group. Ki-67 labeling index was higher in the treated group (p-value 0.00001). The degree of Ki-67 reactivity in the treated group was: negative 6 (15%), weak 6 (15%), moderate 16 (40%) and strong 12 (30%) compared with 18 (45%), 13 (32.5%), 6 (15%) and strong 3 (7.5%) in non-treated group.

CONCLUSION

IL-6 is valuable in the induction of liver cell regeneration. Correlation with biochemical assay and flow cytometric studies is recommended.