免疫检查点抑制剂相关心肌炎小鼠模型的中医证候研究OA

Objective To establish a stable disease-syndrome combination model of immune checkpoint inhibitor-associated myocarditis(ICIM)and comprehensively evaluate its macroscopic manifestations and microscopic biomarkers to elucidate the dynamic evolution of traditional Chinese medicine(TCM)syndromes.Methods Twenty SPF male C57BL/6J mice were randomly divided into model and control groups,with 10 mice per group.From day 8,according to body weight,mice in the model group received intraperitoneal injections of in vivo anti-mouse programmed death 1(25 mg/kg)and cytotoxic T lymphocyte-associated antigen 4(25 mg/kg)monoclonal antibody.In contrast,mice in the control group received intraperitoneal injections of an isotype anti-mouse IgG2a antibody(50 mg/kg).Antibodies were administered once every 3 days for a total of five times.On the 28th day,cardiac function was assessed using echocardiography,including left ventricular ejection fraction(LVEF),left ventricular fractional shortening(LVFS),left ventricular end-systolic volume(LVESV),and left ventricular end-diastolic volume(LVEDV).Histopathological changes in myocardial tissue were evaluated using hematoxylin-eosin(HE)and Masson stainings.Serum contents of cardiac troponin I(cTnI),tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6)were measured using an enzyme-linked immunosorbent assay.The macroscopic manifestations of TCM syndromes in the mice were observed weekly for 4 weeks.On the Thursdays of each week(i.e.,the 4th,11th,18th,and 25th days),general condition was recorded;forelimb grip strength was assessed using a grip strength test,the open field experiment was used to measure the movement distance of the mice within 5 min,and the rectal temperature was measured.On the Fridays of each week(i.e.,the 5th,12th,19th,and 26th days),the exhaustive swimming test was conducted,and the paw temperature,as well as red-green-blue(RGB)values of the tongue surface and both lower limbs were measured.Results Compared with the control group,mice in the model group showed decreased LVEF and LVFS and increased LVESV and LVEDV(P＜0.05);serum contents of cTnI,TNF-α,and IL-6 were elevated(P＜0.05);and HE and Masson stainings revealed disorganized myocardial architecture,prominent immune cell infiltration,and marked fibrosis in the model group.Compared with the control group,mice in the model group exhibited slightly dull and yellowish fur,reduced vigor,decreased activity,and poor claw appearance in weeks 3 and 4;exhaustive swimming time and forelimb grip strength were reduced,whereas rectal temperature was increased(P＜0.05).Compared with the control group,mice in the model group exhibited decreased locomotion distance within 5 min of the open field test in week 4(P＜0.05).Compared with week 1,mice in the model group showed an increased r value and a decreased g value of the tongue surface in week 4(P＜0.05),with no significant change in the b value.Conclusion Based on the comprehensive detection results of macroscopic manifestations and microscopic indicators,the TCM syndromes of ICIM model mice exhibited a dynamic evolution,evolving from the qi deficiency syndrome in week 3 to the qi-yin deficiency syndrome in week 4.