Extraction and purification of serum specific endothelial cell antibody of renal transplant recipients / 器官移植

Objective To investigate the extraction and purification methods of serum specific endothelial cell antibody of renal transplant recipients with rejection after renal transplantation.Methods Human umbilical vein endothelial cell (HUVEC)was isolated and cultured.The serum samples of the renal transplant recipients with poor renal function after renal transplantation were collected.Specific endothelial cell antibody was screened out with flow cytometry;antibodies against human leukocyte antigen (HLA)and major histocompatibility complex class Ⅰ-related chain A (MICA)were detected by Luminex platform.After the existence of specific endothelial cell antibody in the serum sample was confirmed,specific endothelial cell antibody was absorbed with HUVEC.The cell was washed and then the absorbed antibody was eluted from the cell membrane.Antibody IgG in the eluent was purified and concentrated again with Protein-A /G magnetic beads.Antibody activity in the eluent was detected by flow cytometry and the purified specific endothelial cell antibody (IgG)was identified by SDS-polyacrylamide gel (SDS-PAGE)and Western blot.Results In the serum of 386 renal transplant recipients,the serum samples of 5 renal transplant recipients with serum creatinine (Scr) >400 μmoI /L,negative anti-HLA antibody,negative anti-MICA antibody and median fluorescence intensity (MFI) >16 were selected.Purified specific endothelial cell antibody IgG showed immunoglobulin heavy chain (purity > 95%)by SDS-PAGE gel.Flow cytometry showed that the purified antibody had the feature of rebinding with the surface antigen of vascular endothelial cell.Conclusions The purification method of using human umbilical vein endothelial cell to absorb specific endothelial cell antibody in the serum of renal transplant recipients may obtain good effect.

Assessment of reactivity of three treponemal tests in non-treponemal non-reactive cases from sexually transmitted diseases clinic, antenatal clinic, integrated counselling and testing centre, other different outdoor patient departments/indoor patients of a tertiary care centre and peripheral health clinic attendees.

In India, many state reference centres for sexually transmitted infections perform only a single screening assay for syphilis diagnosis. In this study, Treponema pallidum haemagglutination (TPHA) was performed on 1115 Venereal Disease Research Laboratory (VDRL)/rapid plasma regain (RPR) non-reactive and 107 reactive sera out of 10,489 tested by VDRL/RPR according to the National AIDS Control Organisation syphilis testing protocol. A total of 47 Specimens reactive in TPHA and non-reactive with VDRL test were subjected to fluorescent treponemal antibody absorption and enzyme-immunoassay. Seroprevalence considering both VDRL and TPHA positivity was highest (4.4%) in sexually transmitted diseases clinic attendees than in other subject groups. Positivity by two treponemal tests in 24 (2.2%) cases non-reactive by VDRL/RPR was representative of the fully treated patients or latent or late syphilis cases. The findings highlight that a suitable treponemal confirmatory test should be performed in all the diagnostic laboratories.

A Case of Primary Syphilis in the Rectum

A 30-yr-old man was referred for suspicious rectal cancer because of ulcerated lesions in the rectum and a palpable mass in left inguinal area. Sigmoidoscopy showed two indurated masses and histologic evaluation of biopsy revealed obliterative endarteritis with heavy plasma cell infiltration. Both venereal disease research laboratories (VDRL) and fluorescent treponemal antibody absorption (FTA-ABS) tests were positive. After injection of penicillin G benzathine for 3 weeks, the rectal chancre and the palpable mass disappeared.

Detection of congenital syphilis by using fluorescent treponemal antibody absorption test on fractionated sera (FTA-ABS 19s IgM).

The fluorescent treponemal antibody absorption test used with fractionated serum (FTA-ABS 19s IgM test) was evaluated as a test for congenital syphilis. From 1994 to 1995, 32 high-risk infants of mothers with untreated or inadequately treated syphilis and eight adults with primary or secondary syphilis were studied. The FTA-ABS 19s IgM was positive in 6 of 13 symptomatic babies (46 percent) with was a better rate than that given by the older method (38 percent), but only one adult gave a positive test (17 percent). This test was negative in all 50 controls studied, so the specificity was 100 percent. Although a negative FTA-ABS 19s IgM cannot be used to rule out congenital syphilis, a positive test should confirm suspected cases. The clinical features of congenital syphilis, as well as other laboratory investigations, re also discussed.