An antibody that facilitates hematopoietic engraftment recognizes CD44

Pretreatment of recipients with the monoclonal antibody (MoAb) S5 facilitates engraftment of bone marrow from mismatched, unrelated donors in the canine transplantation model. In the direct comparisons reported here, the S5 glycoprotein (gp) was found to have structural homology to CD44 that in humans has been implicated in adhesive interactions of one type of effector cell, the lymphocyte. The S5 antigen and gp90Hermes-1 exhibited codistribution on canine peripheral blood cells. Both S5 and Hermes-1 (anti-CD44) MoAbs recognized 90-Kd species in radioimmune precipitations of 125I surface-labeled canine peripheral blood lymphocytes and bone marrow cells. Competitive antibody binding experiments showed that the epitope detected by S5 was distinct from that bound by Hermes-1 but overlapped with those defined by two other known anti-CD44 reagents, IM7 and Hutch-1. Sequential immunoprecipitation with S5 and Hermes-1 indicated that the two antibodies recognize the same or overlapping subsets of membrane gps. Tryptic digestion of S5 and anti-CD44 immunoprecipitates generated two major iodinated peptides of 27 and 35 Kd in both cases, a further indication of structural homology. Similarly, after N-glycanase digestion, S5 and CD44 immunoprecipitates were resolved to a single 68- Kd species. These findings suggest that CD44-mediated adhesive events may affect the fate of transplanted hematopoietic cells. The previous implications of this gp in T-lymphocyte activation and lymphocyte adhesion to endothelium thus provide useful paradigms to analyze its function in the bone marrow transplant setting.     

Ultraviolet irradiation of blood prevents transfusion-induced sensitization and marrow graft rejection in dogs

In a canine model using DLA-identical littermate pairs, we have shown that a regimen of three transfusions of donor blood given 24, 17, and 10 days before transplant uniformly leads to marrow graft rejection, presumably due to sensitization to minor (non-DLA) histocompatibility antigens. Untransfused dogs uniformly achieve sustained engraftment. In the present study, we investigated whether the exposure of blood to ultraviolet (UV) light (220-300 nm) prior to transfusion prevented sensitization of the recipient and allowed for successful marrow engraftment. Ten dogs were each given three pretransplant transfusions from the marrow donor. Each transfusion consisted of 50 mL of whole blood exposed in vitro to UV light for a total of 1.35 J/cm2. All ten dogs achieved engraftment. In contrast, all four dogs that had received sham-exposed transfusions rejected their grafts. In vitro studies revealed that although cell viability was not affected, leukocytes contained in UV-exposed blood were unable to function as stimulator cells in mixed leukocyte cultures or as accessory cells in mitogen- stimulated cultures. These data are consistent with the hypothesis that accessory cells are involved in transfusion-induced sensitization. We conclude that in vitro exposure of blood to UV light before transfusion prevents sensitization and allows for subsequent marrow engraftment.     

Treatment of estrogen receptor-negative or hormonally refractory breast cancer with double high-dose chemotherapy intensification and bone marrow support

We have used high-dose therapy followed by randomization to receive or not receive autologous bone marrow infusion in 58 stage IV breast cancer patients (all were estrogen receptor-negative [ER-] or primary hormonal refractory). Patients received a median of four courses of induction chemotherapy and if stable or responding received two courses of intensive therapy with cyclophosphamide 4.5 to 5.25 g/m2, etoposide 750 to 1,200 mg/m2, and cisplatin 120 to 180 mg/m2 (CVP). The complete remission (CR) rate after completion of the induction and intensive phases was 55%. Median progression-free interval from induction is 57 weeks with a projected 2-year progression-free survival of approximately 25%. Six of seven patients followed for greater than 2 years are still progression-free. Three favorable features predicted for improved progression-free survival are the following: (1) absent liver involvement, (2) absent soft tissue involvement, and (3) less than or equal to two disease sites (P values of .001, .013, and .048, respectively). Hormonal and menopausal status did not predict for progression-free survival. Major toxicities were infectious secondary to neutropenia, with a 93% incidence of fever and a 38% incidence of sepsis. The treatment-related mortality rate was 9%, with three infectious, one coronary, and one late hemorrhage-related death of unknown cause. Longer follow-up is still needed to truly evaluate the possibility of long-term disease-free survival, but further studies of this approach to high-dose intensification in poor prognostic groups of stage IV breast cancer appear warranted.     

Flow cytometric immunophenotyping in posttransplant lymphoproliferative disorders.

We studied the flow cytometric immunophenotyping (FCI) and genotypic data of 11 specimens from 10 transplant recipients and categorized them based on a scheme for posttransplant lymphoproliferative disorders (PTLDs). Specimens had been analyzed by polymerase chain reaction and/or Southern blot for T-cell and B-cell (immunoglobulin heavy chain and light chain genes) gene rearrangements (BGR). The categories for PTLDs were as follows: 1, 1; 2, 6; and 3, 4. The plasmacytic and polymorphic B-cell hyperplasias (PBCHs) revealed no monoclonal/aberrant cells by FCI or genotypic studies (GS). Three of 4 polymorphic B-cell lymphomas (PBCLs) revealed monoclonal or aberrant (no surface light chain) B cells by FCI; 1 of 3 revealed a BGR. However, the 1 case with no monoclonal/aberrant B cells by FCI revealed a BGR. Both immunoblastic lymphomas revealed monoclonal or aberrant B cells by FCI; 1 revealed a BGR. Both multiple myelomas revealed monoclonal plasma cells by FCI; 1 revealed a BGR. In the 4 PTLDs with monoclonal/aberrant B cells by FCI and no clonality detected by GS, the GS were performed on fresh and paraffin-embedded tissue samples. FCI of the plasmacytic and PBCHs supported no clonal process by GS. FCI defined a clonal process in 2 PBCLs, I immunoblastic lymphoma, and 1 multiple myeloma that were negative by GS. However, 1 PBCL that was polyclonal by FCI was monoclonal by GS. Thus, FCI is useful for identifying a clonal process in PTLDs with negative results by GS; FCI and GS should be performed routinely in PTLDs to detect a clonal process.     

Childhood scoliosis: MR imaging

The spinal cords of 28 scoliosis patients between the ages of 1 month and 17 years were examined with magnetic resonance (MR) imaging. Complete visualization was obtained in all cases. In 15 patients (53%) neuropathologic abnormalities demonstrated by MR imaging significantly affected their clinical course, including tethered cords (n = 7), syringomyelia (n = 5), Arnold-Chiari I malformation (n = 4), spinal cord tumors (n = 2), Arnold-Chiari II malformation (n = 3), and diastematomyelia (n = 1). The advantages of MR imaging in the evaluation of the scoliotic spine in children include a high sensitivity for the occult conditions associated with scoliosis, good anatomic demonstration of the cord, and absence of bone artifacts. MR imaging is recommended as a primary imaging modality in scoliosis, following conventional radiography.     

胶原海绵复合新生大鼠原代心肌细胞构建工程化心肌组织

目的:探索以胶原海绵为支架、新生大鼠原代心肌细胞为种子细胞,于体外构建工程化心肌组织的方法。方法:实验于2005-12/2006-11在解放军第四军医大学西京医院心内科实验室完成。Ⅰ型胶原海绵剪切成方形片状(2.0cm×1.4cm×0.2cm),经60Co照射消毒,于DMEM培养液中水化1h左右。另取1d龄SD大鼠心脏,剪成小碎块,然后用2.5g/L胰蛋白酶于37℃中消化,吸取上清至含胎牛血清的DMEM中,重复消化四五次,用差速贴壁法除去大部分成纤维细胞,将细胞沉淀用DMEM培养液以2×109L-1的密度悬浮备用。将上述的心肌细胞悬液1mL缓慢滴注于玻璃模型中的胶原海绵上,然后置于细胞培养中培养。肉眼及显微镜主要观察工程化心肌组织在培养期间的自发收缩情况,包括收缩的部位、强度、频率、一致性以及收缩随时间变化的情况。苏木精-伊红染色观察工程化心肌组织内胶原纤维的变化,细胞形态,胞核的形状及细胞之间的连接。免疫组织化学染色和透射电镜观察工程化心肌组织片的形态和功能。结果:①细胞接种于胶原海绵上1d后,细胞/胶原复合物的凝胶化过程基本完毕,体积保持恒定,维持至培养结束,第3天细胞/胶原复合物局部出现点片状自发收缩,第5天整个细胞/胶原复合物出现同步化自发收缩,收缩频率61～199次/min。2周后37.5%的工程化心肌组织的自发收缩活动减弱,但75%的工程化心肌组织的自发收缩活动持续至培养结束。②苏木精-伊红染色、免疫组织化学染色和透射电子显微镜显示,工程化心肌组织内细胞间连接广泛存在,细胞多呈纵向分布,胞核呈长圆形,胞浆内α-肌节肌动蛋白阳性,胞内肌原纤维排列整齐,可见到心肌特异性的肌小节结构和Z线,多数细胞具有分化的心肌细胞表型。结论:用新生大鼠原代心肌细胞为种子细胞、以Ⅰ型胶原海绵为支架材料,构建出的工程化心肌组织,于体外可长时间持续自发收缩,该细胞/胶原复合物的形态结构与生理功能均类似于成熟大鼠心肌组织。     

胰岛移植过程中胰岛培养的研究现状

目的:总结胰岛移植过程中胰岛培养的研究现状,为利用胰岛培养准备更多更好的胰岛提供理论依据和技术支持。资料来源:以计算机检索Medline和Pubmed数据库1994-01/2007-01与胰岛培养相关的文章,检索词为“isle,tculture”,限定文章语言种类为English。同时计算机检索CNKI中国全文数据库1994-01/2007-01与胰岛培养相关的文章,检索词为“胰岛,培养”,限定文章语言种类为中文。资料选择:对资料进行初审,纳入标准:①与胰岛培养相关的文章。②1994年以后发表的文章。排除标准:Meta分析类文章。资料提炼:共检索到1384篇与胰岛培养相关的文章,入选33篇。对所检索文章的相关信息加以综合概括,其中关于胰岛培养中基础培养基、培养添加物、培养温度、密度等方面的文章18篇,关于胰岛培养新尝试的文章12篇。资料综合:将胰岛培养后再行移植有一定优势,包括降低免疫原性和为术前准备赢得时间等。目前对于挑选合适培养基及其添加物,调整合适培养温度、培养密度以及保护胰岛的活性等都有了比较深入细致的研究;同时很多学者开始尝试一些新的方法延长胰岛培养时间,改善胰岛功能,包括加入细胞外基质、与其他细胞共培养、选用微重力系统培养以及利用胶囊包裹培养等均显示良好的效果。结论:虽然胰岛培养可能会影响胰岛的活性和功能,但随着对胰岛生理和病理生理特性研究的深入,新的技术方法可将这些影响降到最低。胰岛培养给临床实践带来的便利是其最大的优势,加强胰岛培养的研究与应用有着重要的意义。     

Serum epidermal growth factor receptor and HER2 expression in primary and metastatic breast cancer patients

Background  

Breast tissue expression of the ERBB proto-oncogene family has been extensively studied. It was recently shown that expression of epidermal growth factor receptor (EGFR; c-erbB-1) and epidermal growth factor receptor (HER)2 (c-erbB-2) can be detected in the serum of breast cancer patients. The clinical relevance of this has not been fully established.     

Pitfalls in CT diagnosis of appendicitis: Pictorial essay

Despite the high diagnostic accuracy of CT for appendicitis, numerous pitfalls exist that may result in a misdiagnosis. This pictorial review outlines the potential pitfalls in the CT diagnosis of appendicitis that includes atypical position of the appendix and coexisting pathologies. Various mimickers of appendicitis and clinical dilemmas will be highlighted. Upon completion, the reviewer should have an improved ability to recognise appendicitis mimickers and identify equivocal or atypical findings.