[Establishment of Secondary HLH Mouse Model and Effect of Ruxolitinib on Disease Manifestations of Model Mide]

To establish a secondary hemophagocytic lymphohistiocytosis(HLH) mouse model, and to investigate the effect of ruxolitinib on the disease manifestation of model mice.

Wild type C57BL/6 mice were randomly divided into 4 groups: two groups of mice were intraperitoneally injected with CpG oligodeoxynucleotide 1826 (CpG-ODN1826) every other day to induce HLH, and other two groups were control groups. One group of the CpG-ODN1826 groups and one of the control groups were given ruxolitinib, and other two groups were given the same amount of PBS. Blood samples, serum ferritin and hepatic/spleen weights of experimental mice were detected and serum cytokine levels were measured by ELISA.

Compared with the control groups, the levels of white blood cells, hemoglobin and platelets in the CpG-ODN1826 groups were significantly lower (P＜0.05); and liver/body weight, spleen/body weight, serum ferritin, sCD25, IL-10, IL-1β, IFN-Ƴ, IL-12p70, GM-CSF, TNF-α and IL-18 levels significantly increased (P＜0.05). There was no significant difference in the levels of IL-2, IL-4, IL-5, IL-6, IL-22, IL-13, IL-27 and IL-23 between the two groups (P＞0.05). The spleen in CpG group had disordered internal structure, expanding red pulp and hyperplastic nucleated cells. The liver had severe perivascular inflammations. The spleen/weight of the ruxolitinib-treated mice in the CpG-ODN1826 group was significantly smaller than that of the unapplied ruxolitinib (P＜0.05).

The CpG-ODN1826 can induce secondary HLH symptoms in wild type C57BL/6 mice. Ruxolitinib can alleviate the symptoms of splenomegaly in HLH model mice.