儿童紫癜性肾炎肾组织Th1/Th2比值与肾脏微血管损伤的关系

Relationship between renal Th1/Th2 ratio and renal microvascular injury in children with Henoch-Schnlein purpura nephritis

目的探讨儿童紫癜性肾炎(HSPN)肾组织Th1/Th2比值与肾脏微血管损伤的关系。方法选取32名HSPN患儿为病例组,根据肾脏病理结果分为4个亚组:HSPNⅡ级(n=8),Ⅲa级(n=7),Ⅲb级(n=10)及Ⅵ/Ⅴ级(n=7)。5例因肾外伤切除肾组织患者为对照组。免疫组化法检测肾组织INFγ(标记Th1细胞)、IL-4(标记Th2细胞)及CD34(标记微血管)的表达,并进行微血管评分,计算微血管密度(MVD),分析肾脏INFγ、IL-4表达与肾脏病理分级、肾脏微血管评分和MVD之间的关系。结果与对照组相比,病例组肾组织INFγ表达降低,IL-4表达升高,Th1/Th2比值随着HSPN病理损伤的加重而减小,各级间差异有统计学意义(P<0.05)。与对照组比较,HSPNⅡ级和Ⅲa级组MVD显著增加,但Ⅳ/Ⅴ级组MVD显著减少(P<0.05)。与对照组和HSPNⅡ级组比较,HSPNⅢa级、Ⅲb级以及Ⅳ/Ⅴ级组肾脏微血管评分明显增加,且随病理分级的增加,肾脏微血管评分逐渐增加,各级间差异有统计学意义(P<0.05)。肾组织Th1/Th2比值与微血管密度变化呈负相关(r=-0.921,P<0.01)。结论 Th1/Th2比值降低可能参与了HSPN肾脏微血管损伤。

Objective To explore possible correlations between renal Th1/Th2 ratio and renal microvascular injury in children with Henoch-Schnlein purpura nephritis（HSPN）.Methods Thirty-two children with HSPN were enrolled.They were classified into four groups by renal pathology： HSPN class II（n=8）,HSPN class IIIa（n=7）,HSPN class IIIb（n=10） and HSPN class IV/V（n=7）.Five patients undergoing nephrectomy due to trauma were used as the controls.INFγ,IL-4 and CD34 in the renal tissues were measured by immunohistochemical analysis.INFγ was used as a marker of Th1,IL-4 was used as a marker of Th2 and CD34 was used as a marker of microvessel.The renal microvessel density was evaluated according to the Weidner standard.The relationships among the local Th1/Th2 ratio,renal pathological grade,microvessel score and microvessel density were studied.Results Immunohistochemical analysis showed a lower expression of INFγ and a higher expression of IL-4 in the HSPN groups than in the control group.The local Th1/Th2 ratio in the HSPN groups decreased and correlated significantly with the renal pathological grade.There were significant differences among four HSPN subgroups（P0.05）.Compared with the control group,the renal microvessel density in the HSPN class II and class IIIa groups increased significantly（P0.05）,but it decreased in the HSPN class IV/V group（P0.05）.The renal microvessel scores in the HSPN class IIIa,class IIIb and class IV/V groups increased significantly compared with those in the control and the HSPN classⅡ.The increased renal microvessel scores were associated with more severe renal pathological changes.A negative correlation was found between the local Th1/Th2 ratio and the microvessel density in kidneys（r=-0.921,P0.01）.Conclusions The decrease of Th1/Th2 ratio in kidneys might be responsible for renal microvascular injury in children with HSPN.