Expression And Clinical Significance Of CD52 And Its Soluble Forms In Central Nervous System Hemangioblastomas

Expression and clinical significance of CD52 and Its Soluble Form In Central Nervous System HemangioblastomasSectionⅠExpression of CD52 In Central Nervous System HBsObjectiveTo detect the expression and distribution of CD52 in central nervous system hemangioblastomas(HBs).MethodsTwenty samples of HBs were collected from surgical operations in Department of Neurosurgery,Huashan Hospital,FDU between Jan 2006 and Dec 2007.Among them,three samples were randomly chosen and examined by electron microscopy.All samples were applied to characterize CD52 by HE staining and immmunohistochemical single/double staining respectively.CD52 was detected in the protein extract from the tumor tissues by westemblot.ResultsThe HBs tissues presented two kinds of morphology,cystic or solid,and are composed of abundant capillary network and stromal cells.Vessels were circled by unilaminar flat endothelial cell,surrounding with perithelial cells.Compared with normal brain tissues,CD52 expression was much higher in HBs by immmunohistochemical staining(P＜0.05),but there was no significant difference betweem cystic and solid group(P＞0.05).All the three different kinds of cells in HBs showed positive staining for vimentin,while only stromal cells positive for CD52,endothelial cells for CD34,and perithelial cells forα-SMA.The results of westernblotting for CD52 were consistent with immmunohistochemical staining.Conclusion Relative high expression of CD52 was detected in the stromal cells of CNS HBs,suggesting a potential new clue to the diagnosis and management of the disease. SectionⅡIn-vitro culturing of primary HBs cells and their expression of CD52ObjectiveTo culture HBs cells in-vitro and detect their expression and distribution of CD52.MethodsTen fresh samples of HBs were collected from surgical operations in Department of Neurosurgery,Huashan Hospital,FDU.between Jan 2006 and Dec 2007.Primary HBs cells were harvested by adherence screening method and grown in DMEM for serial subcultivation.Inverted phase contrast microscope was used to observe the morphological.and growing characteristics of HBs cells in vitro.Immunofluorescence (IF) method was introduced into examining the CD52 distribution in the HBs cells. Western-blot was also applied to detect CD52 and its soluble form in cultured cells and supematant,respectively.ResultsPrimary HBs cells could be cultured and grew well in DMEM in vitro.Stromal cells were the major component of the tumor accounting for more than 80%in the in-vitro cultured cells which thrived and lived longer.IF showed that CD52 were expressed strongly in cultured cells,but expressions of CD34 orα-SMA were rarely detected.Confocal laser scanning microscopy showed that CD52 particles were expressed in the cell membrane,the cytoplasm closed to the membrane and extracellular area.Also the soluble form of CD52 were detected in the isolated supernatant and cultured cell by westernblotting.ConclusionsStromal cell was the substantial tumor cell of HBs.In the HBs in-vitro culturing system,CD52 was highly expressed and shed into the supernatant,providing a new potential diagnostic method for the Central Nervous System HBs. SectionⅢExpression of soluble CD52 in the body fluid of patients with HBsObjectiveTo detect the soluble form of CD52 in the body fluid of HBs patients.MethodsTwenty patients with HBs were surgically treated in Department of Neurosurgery, Huashan Hospital,FDU between Jan 2006 and Dec 2007.Samples of blood and urine were collected before operation and one day,one week,and one month after operation, CSF samples were collected during operation as well in 20 patients.Samples of cystic fluid were also harvested during operation from 7 patients with cystic tumors. Westernblot analysis was employed to examine the expression of soluble CD52 in the body fluid of HBs patients before and after operations.Moreover sCD52 detection was used to careen predict the morbidity in the relatives of a patient suffered from VHLD.ResultsCompared with health adult,sCD52 expression was very high in serum,urine,CSF and cystic fluid of all 20 patients collected before and during operation.The level of serumal and urinary sCD52 in 13 patient with sporadic HBs who underwent total resection didn't began to decline one day after operation but did one week,and the level of sCD52 one month after operation was same to that of one week.The level of serumal and urinary sCD52 in the other 2 patients underwent incomplete tumor resection and 5 patients with VHLD did not change after operation. Positive expression of sCD52 were detected in the urine evacuated by 3/6 relatives of a VHLD patient who have family history,and One of them was further confirmed a renal carcinoma by CT scan and multiple intracranial HBs by MRI,and the other one is a patient with recurrent HBs that was resected before.The third one was negative examinations so far.The other three relatives had a negative expressions of sCD52 in their urine.ConclusionsSoluble forms of CD52 exist in the body fluid of patients with HBs,providing a potential marker for the preoperative screening,diagnosis,and post-operative follow-up study for patients with Central Nervous System HBs.