Minor histocompatibility antigens HA-1-, -2-, and -4-, and HY-specific cytotoxic T-cell clones inhibit human hematopoietic progenitor cell growth by a mechanism that is dependent on direct cell-cell contact

HLA-identical bone marrow transplantation (BMT) may be complicated by graft-versus-host disease or graft rejection. Both complications are thought to be initiated by recognition of minor histocompatibility (mH) antigens by HLA-restricted mH-antigen-specific T lymphocytes. Using HLA- A2-restricted mH antigens HA-1-, -2-, and -4-, and HY-specific cytotoxic T lymphocyte (CTL) clones, we studied the recognition by these CTL clones of interleukin-2 (IL-2)-stimulated T cells (IL-2 blasts), BM mononuclear cells (BMMNCs), and hematopoietic progenitor cells (HPCs). We showed that, when IL-2 blasts from the BM donors who were investigated were recognized by the HA-1-, -2-, and -4-, and HY- specific CTL clones, their BMMNCs and HPCs were recognized as well by these CTL clones, resulting in antigen-specific growth inhibition of erythrocyte burst-forming units (BFU-E), colony-forming units- granulocyte (CFU-G), and CFU-macrophage (CFU-M). the HA-2-specific CTL clone, however, inhibited BFU-E and CFU-G growth from four donors to a lesser extent than from two other donors. We further investigated whether inhibitory cytokines released into the culture medium by the antigen-specific stimulated CTLs or by stimulated BMMNCs were responsible for suppression of HPC growth or whether this effect was caused by direct cell-cell contact between CTLs and HPCs. HPC growth inhibition was only observed after preincubation of BMMNCs and CTLs together for 4 hours before plating the cells in semisolid HPC culture medium. When no cell-cell contact was permitted before plating, neither antigen-stimulated CTL nor antigen-nonstimulated CTLs provoked HPC growth inhibition. Culturing BMMNCs in the presence of supernatants harvested after incubation of BMMNCs and CTL clones together for 4 or 72 hours did also not result in HPC growth inhibition. Both suppression of HPC growth and lysis of IL-2 blasts and BMMNCs in the 51Cr-release assay appeared to be dependent on direct cell-cell contact between target cells and CTLs and were not caused by the release of inhibitory cytokines into the culture medium by antigen-specific stimulated CTLs or by stimulated BMMNCs. Our results show that mH-antigen-specific CTLs can inhibit HPC growth by a direct cytolytic effect and may therefore be responsible for BM graft rejection after HLA-identical BMT.     

The major histocompatibility complex region marked by HSP70-1 and HSP70- 2 variants is associated with clozapine-induced agranulocytosis in two different ethnic groups

Genes of the major histocompatibility complex (MHC) have been associated with susceptibility to drug-induced adverse reactions. We previously found that clozapine-induced agranulocytosis (CA) is associated with the HLA-DRB1*0402, DRB4*0101, DQB1*0302, DQA1*0301 haplotype in Ashkenazi Jewish patients and with the HLA-DRB1*1601, DRB5*02, DQB1*0502, DQA1*0102 haplotype in non-Jewish patients. In the present study, we tested the hypothesis that the variants of the heat- shock protein 70 (HSP-70) encoded by the HSP-70 loci located within the MHC region and known to be involved in apoptosis and regulation of cell proliferation could play an important role in molecular mechanisms of CA. First, we analyzed HSP70-2 polymorphism in risk-associated haplotypes from HLA homozygous cells and normal individuals and confirmed that the HSP70-2 9-kb variant was associated invariably with DR4 (HLA-DRB1*0402, DQB1*0302) and DR2 (HLA-DRB1*01601, DQB1*0502, DQA1*0102 and HLA-DRB1*1501, DQB1*0602) haplotypes, which were the haplotypes found increased in Jewish and non-Jewish patients with CA, respectively. The 9.0-kb variant was also found to be associated with HLA-B44, DRB1*0401 and HLA-B44, DRB1*07 haplotypes. Second, in patients with CA (12 Ashkenazi Jewish and 20 non-Jewish patients), HSP70-1 A and HSP70-2 9.0-kb variants were associated with the MHC haplotypes found by us to be markers of susceptibility to CA. The clozapine-treated control group had an excess number of HSP70-1 C and HSP70-2 8.5-kb variants, consistent with genetic resistance to CA associated with those variants. This finding supports our hypothesis that a dominant gene within the MHC region (marked by HSP70-1 and HSP70-2), but not necessarily HLA, is associated with CA in two different ethnic groups.     

The novel use of a biodegradable stent placed by percutaneous transhepatic cholangiography for the treatment of a hepaticojejunostomy biliary leak following an extended left hepatectomy and pancreaticoduodenectomy

A 61-year-old man presented with jaundice, and subsequently underwent an extended left hepatectomy and pancreaticoduodenectomy for a cholangiocarcinoma invading the head of the pancreas. The patient developed sepsis due to a biliary leak at the hepaticojejunostomy. We describe the original use of a biodegradable stent, deployed via percutaneous transhepatic cholangiography into the Roux limb, resulting in good drainage and resolution of sepsis. The chief benefit of this procedure is the lack of need for subsequent removal as well as purported reduced biofilm accumulation. We believe this to be the first reported case of this type and the literature surrounding the subject is also discussed.     

Microtubule reassembly in surface-activated platelets

It is generally accepted that a circumferential microtubule supports the discoid shape of resting platelets. The fate of the many-coiled polymer following platelet activation, however, has been a subject of considerable debate. Morphological investigations have suggested that the circumferential coils are constricted into tight rings around centrally concentrated organelles during platelet shape change. Biochemical studies employing colchicine-binding assays, on the other hand, have indicated that the bundle of microtubules dissolves almost completely within seconds after activation and reassembles in a new location one to four minutes later. The present study has accepted the latter hypothesis in order to examine the second part of the disassembly-reassembly theory proposed in biochemical studies. Platelets exposed to low temperatures sufficient to remove all microtubules were placed on glass slides and microscope grids to cause surface activation during rewarming. The combined stimuli of rewarming and surface activation might have been expected to cause more rapid assembly than warming alone or activation alone. This was not the case. Reassembly of microtubules during rewarming and simultaneous surface activation was not accelerated. In contrast to the constriction of microtubule rings observed during activation in control platelets, the diameters of coils that developed in chilled platelets one to two hours after rewarming and surface activation were twice those of control cells.     

Improving sensitivity of cervical cytology by removal of cervical secretions before sampling: a prospective study in Mexico

Sensitivity of cervical cytology is suboptimal, especially in developing countries such as Mexico, despite available guidelines aimed at improving this. When obtaining cervical samples, whether the samples are taken from the transformation zone and whether abnormal cells are missing must be considered. Cervical secretions (CS) are always present in variable proportions, and when cleaning the cervix, better samples may be obtained. In this study, we analyzed samples obtained with or without cleaning the cervix, and compared their contents in order to determine the sensitivity and specificity of these two methods. Methods: Of 500 patients who underwent cytology and colposcopy, 271 (54.2%) required a second opinion due to a diagnosis of cervical intraepithelial neoplasia (CIN). CS was removed and compared with the clean, second sample (SS) using in both liquid-based cytology. The quality of samples according to the Bethesda System, the presence of CIN, and inflammatory reactions were recorded. The sensitivity and specificity were calculated using biopsy as the gold standard. Results: The SS resulted in a higher proportion of adequate samples being obtained (97.6% vs. 44.8%), and in increased sensitivity (88.2% vs. 58.8%). CIN was detected in the SS 26% more often than in the CS (34 vs. 27 samples), whereas inflammatory reactions were noted more often in the CS (91.4% vs. 74%). Conclusion: Cervical sampling including CS results in lower sensitivity and CIN detection rates, and in more inflammatory reactions. By excluding CS from cervical samples, the sensitivity could be improved and the false negative rate could be reduced.     

肝脏可溶性复合物不同剂量、不同途径移植对肿瘤细胞增殖抑制的体内外实验

目的:肝脏可溶性复合物具有保护肝脏、刺激肝组织再生等生物学活性,观察天然物质肝脏可溶性复合物对肿瘤细胞生长增殖的抑制作用.方法:实验于2006-05/2007-02在四川大学华西医院生物治疗国家重点实验室实验肿瘤研究室完成.①分离人胚胎、成年及新生小鼠肝脏组织,生理盐水清洗、剪碎、筛网过滤,用生理盐水制备混悬液,3 000 r/min离心,收集上清,制备肝脏可溶性复合物.②体外实验:用上述不同来源的肝脏可溶性复合物体外处理肿瘤细胞,四甲基偶氮唑盐比色法测定其对乳腺癌细胞EMT6增殖的影响.③体内实验:观察成年鼠肝脏可溶物质对乳腺癌细胞EMT6体内生长的抑制作用及其对荷瘤鼠生存状况的影响,包括不同给药剂量及不同给药途径两个实验,给药途径包括在接种肿瘤细胞部位的对侧腋下、同侧腋下、腹腔注射及灌胃等.结果:①体外实验显示不同来源的肝脏可溶性复合物能明显抑制肿瘤细胞EMT6增殖率,肿瘤增殖抑制率均显著高于血清白蛋白处理组(P＜0.05),并呈剂量依赖性.②成年鼠肝脏可溶物质8mg/L组抑瘤率高于2,4 mg/L组(P＜0.05),未观察到明显毒副效应.③比较不同给药途径,成年鼠肝脏可溶物质同侧注射组的抑瘤率较其他3组的抑瘤率高(P＜0.05),各成年鼠肝脏可溶物质给予组的体质量增长率比相应生理盐水对照组高(P＜0.05).④与相应生理盐水对照组比较,在同侧腋下注射成年鼠肝脏可溶物质的小鼠生存期明显延长(P＜0.05).结论:肝脏可溶性复合物具有抑制肿瘤细胞生长的作用,并且呈一定的剂量依赖性.不同的给药途径中,在接种肿瘤细胞部位的同侧腋下给药抑瘤效果最好.     

山东泰安地区两个自然村人群血脂状况调查

目的:调查了解山东泰安地区农村人群的血脂水平,为该地区农民心脑血管疾病的预防提供基础数据。方法:实验于2006-06随机选取泰安市两个自然村650人进行健康检查,男270人,女380人,年龄2～88岁。①650人均于早晨空腹采集静脉血3mL,静置凝固后,2h内分离血清,采用全自动生化分析仪常规测定患者血脂指标总胆固醇、三酰甘油水平。②总胆固醇>5.2mmol/L判定为高胆固醇血症,三酰甘油>1.7mmol/L判定为高三酰甘油血症。结果:650人全部完成血样采集与血脂指标检测。①不同性别血脂水平比较:被检人群男性三酰甘油水平显著高于女性[(1.16±1.47),(0.95±0.84)mmol/L,P<0.05];男女总胆固醇水平基本相似(P>0.05)。②不同年龄段血脂水平比较:8人因具体年龄段不祥被排除,剩余642人分为3个年龄段:2～30岁、31～50岁、51～88岁。结果31～50岁人群三酰甘油水平显著高于2～30岁人群[(1.14±1.47),(0.88±0.70)mmol/L,P<0.05],略高于51～88岁人群(P>0.05);51～88岁人群总胆固醇水平>31～50岁人群>2～30岁人群,相邻年龄段间比较差异均有显著性意义(P<0.001)。③各年龄段男女间血脂水平比较:2～30岁人群和51～88岁人群三酰甘油水平性别间差异均无显著性意义(P>0.05),但总胆固醇水平女性均显著高于男性[(2.38±1.47),(1.85±1.26)mmol/L,P<0.05;(4.48±0.92),(4.18±0.76)mmol/L,P0.01]。31～50岁人群男性三酰甘油水平显著高于女性[(1.51±2.06),(0.90±0.80)mmol/L,P<0.01],总胆固醇水平基本相似(P>0.05)。④各年龄段男女高血脂症构成比:31～50岁人群高三酰甘油血症构成比显著高于2～30岁、51～88岁人群(23.1%,5.5%,9.3%,P<0.01);随着年龄增高,各年龄段高胆固醇血症构成比逐渐升高,相邻年龄段间差异均有显著性意义(2.7%,8.6%,15.6%,P<0.01)。31～50岁人群男性高三酰甘油血症、高胆固醇血症的构成比显著高于女性(P<0.01);2～30岁、51～88岁人群男女间高血脂症的构成比基本相似(P>0.05)。结论:①山东泰安地区农村人群高三酰甘油血症,31～50岁年龄段患病率最高;高胆固醇血症患病率随年龄增长逐步上升,提示中年人健康体检尤为重要。②高脂血症应从青少年开始加大预防和保健力度,进行广泛和反复的健康教育,倡导健康的生活方式和生活行为。