天麻钩藤饮联合醒脑开窍针刺法对急性脑梗死患者血管内皮功能、脑血管储备功能及CD62P、CD63表达的影响

摘要 目的：探讨天麻钩藤饮联合醒脑开窍针刺法辅助治疗对急性脑梗死患者血管内皮功能、脑血管储备功能及血小板表面-颗粒膜糖蛋白（CD62P）、溶酶体膜糖蛋白（CD63）表达的影响。方法：选择2017年1月至2019年12月收治的急性脑梗死患者80例,依照随机数字表法分为对照组（40例,予以常规治疗）和观察组（40例,常规治疗的基础上给予天麻钩藤饮联合醒脑开窍针刺法辅助治疗）,比较两组临床有效率及治疗前后的美国国立卫生研究院卒中量表（NIHSS）评分、长谷川智能量表（HDS）评分、Barthel指数、血管内皮功能指标（包括一氧化氮（NO）、内皮素-1（ET-1））、脑血管储备功能指标[脑血管储备功能（CVR）、脉动指数（PI）]及血小板CD62P、CD63水平。结果：观察组的临床总有效率为92.50%（37/40）,对照组的临床总有效率为70.00%（28/40）,2组比较差异有统计学意义（P<0.05）。观察组NIHSS评分明显低于对照组,HDS评分和Barthel指数均明显高于对照组（P<0.05）。观察组治疗后血清NO、CVR水平水平明显高于对照组,血清ET-1、PI及血小板CD62P、CD63表达水平均明显低于对照组（P<0.05）。结论：在常规治疗的基础上,天麻钩藤饮联合醒脑开窍针刺法辅助治疗急性脑梗死的临床疗效显著,能够明显改善血管内皮功能、脑血管储备功能、神经功能,提高生活质量,改善血小板CD62P、CD63表达。     

血清CD163、AFU、miR202在原发性肝癌诊断中的作用及在介入治疗前后的变化

摘要 目的：探讨血清CD163、α-L-岩藻糖苷酶（AFU）、微小核糖核酸202（miR202）在原发性肝癌诊断中的作用及在介入治疗前后的变化。方法：选择本院2018年5月~2020年6月收治的106例原发性肝癌患者，均予以肝动脉化疗栓塞术（TACE）治疗，同期选择本院收治的94例肝硬化患者纳入疾病对照组，门诊健康体检者113例纳入健康对照组。对比三组血清CD163、AFU、miR202，原发性肝癌患者治疗前后CD163、AFU、miR202。结果：原发性肝癌组血清CD163、AFU高于疾病对照组及健康对照组，差异有统计学意义（P<0.05），miR202低于对照组及健康对照组（P<0.05）；疾病对照组血清CD163、AFU高于健康对照组（P<0.05），miR202低于健康对照组（P<0.05）。原发性肝癌患者治疗后血清CD163、AFU低于治疗前，差异有统计学意义（P<0.05）；miR202高于治疗前，差异有统计学意义（P<0.05）。治疗前及治疗后，好转组血清CD163、AFU水平均低于无效组，差异有统计学意义（P<0.05），miR202高于无效组，差异有统计学意义（P<0.05）；治疗后，好转组血清CD163、AFU水平低于治疗前（P<0.05），miR202高于治疗前（P<0.05），无效组治疗前后血清CD163、AFU、miR202差异无统计学意义（P>0.05）。结论：血清CD163、AFU、miR202能够辅助原发性肝癌的诊断，又可为TACE的疗效评价提供参考依据。     

沙丁胺醇联合布地奈德雾化吸入对支气管哮喘患儿血清AT-III、CD5L以及炎症水平的影响

摘要 目的：探讨沙丁胺醇联合布地奈德雾化吸入对支气管哮喘患儿血清AT-III、CD5L以及炎症水平的影响。方法：选取我院2018年10月到2020年10月共收治的78例支气管哮喘患儿作为研究对象,将所有患儿随机分为观察组与对照组,每组39例。对照组患儿应用布地奈德雾化吸入治疗,观察组患儿应用沙丁胺醇联合布地奈德雾化吸入治疗,对比两组患儿的治疗效果、治疗前后的FeNO、肺功能指标、血气指标、血清AT-III、CD5L以及外周血单个核细胞NLRP3炎症小体变化情况。结果：观察组患儿的治疗总有效率为97.44%,显著高于对照组的82.05%（P＜0.05）;两组患儿治疗前PEF、FVC、FEV1指标对比无显著差异（P＞0.05）,通过治疗后观察组患儿的PEF、FVC、FEV1指标明显优于对照组,组间对比,差异具有统计学意义（P＜0.05）;通过对比各项肺功能指标发现,两组患儿治疗后PaO₂、PaCO₂、SaO₂指标对比差异均无统计学意义（P＞0.05）;两组患儿治疗前FeNO、AT-III、CD5L以及外周血单个核细胞NLRP3炎症小体表达对比无明显差异（P＞0.05）;治疗后,观察组患儿FeNO、AT-Ⅲ水平以及NLRP3 mRNA表达均显著低于对照组,CD5L水平高于对照组（P＜0.05）。结论：对支气管哮喘患儿应用沙丁胺醇联合布地奈德雾化吸入治疗,能够减轻患儿临床症状,提高治疗效果,提升患儿肺功能,稳定血气指标,减轻慢性缺氧状态,提升免疫力,降低炎症反应,值得临床应用推广。     

视频脑电图联合PEWS评分、NSE、CD4+/CD8+比值对病毒性脑炎患儿病情评估及预后预测的临床价值

摘要 目的：探讨视频脑电图（VEEG）联合儿童早期预警评分（PEWS）、神经元特异性烯醇化酶（NSE）、CD4⁺/CD8⁺比值对病毒性脑炎患儿病情评估及预后预测的价值。方法：选择2020年3月至2022年3月南京医科大学附属儿童医院收治的152例病毒性脑炎患儿，根据病情严重程度将患儿分为重症组（67例）和轻症组（85例），另选择72例无神经系统损伤住院患儿为对照组。治疗2周后，根据儿童格拉斯哥预后量表（CGOS）将其分为预后良好组（4~5级，89例）与预后不良组（1~3级，63例）。所有研究对象均接受PEWS测评和VEEG检查，检测血清NSE水平，计算CD4⁺/CD8⁺比值。采用单因素和多因素Logistic回归分析影响病毒性脑炎患儿预后的因素。采用受试者工作特征（ROC）曲线分析PEWS、VEEG 及血清NSE、CD4⁺/CD8⁺比值预测病毒性脑炎患儿预后的价值。结果：重症组PEWS、VEEG重度异常比例及血清NSE水平高于轻症组和对照组，CD4⁺/CD8⁺比值低于轻症组和对照组（P＜0.05）；轻症组PEWS、VEEG重度异常比例及血清NSE水平高于对照组，CD4⁺/CD8⁺比值低于对照组（P＜0.05）。预后不良组PEWS、VEEG重度异常比例、血清NSE水平高于预后良好组，CD4⁺/CD8⁺比值低于预后良好组（P＜0.05）。多因素Logistic回归分析结果显示，持续惊厥、高PEWS、VEEG重度异常、血清NSE水平升高是病毒性脑炎患儿预后不良的危险因素，CD4⁺/CD8⁺比值升高是保护因素（P＜0.05）。联合PEWS、VEEG 及血清NSE、CD4⁺/CD8⁺比值预测病毒性脑炎患儿预后曲线下面积为0.859，高于各指标单独预测。结论：病毒性脑炎患儿高PEWS、VEEG重度异常、血清NSE水平升高、CD4⁺/CD8⁺比值降低，与病情加重和预后不良有关，联合以上四项指标辅助预测病毒性脑炎患儿预后的价值较高。     

传染性单核细胞增多症患儿NLR、CD4+/CD8+比值、ADA与EBV-DNA载量的相关性分析及对肝损害的影响

摘要 目的：探讨传染性单核细胞增多症（IM）患儿外周血中性粒细胞/淋巴细胞比值（NLR）、CD4⁺/CD8⁺比值、腺苷脱氨酶（ADA）与EB病毒（EBV）-脱氧核糖核酸（DNA）载量的相关性,分析其对IM患儿肝损害的影响。方法：选择2019年1月至2022年4月我院儿科收治的102例IM患儿（IM组）,另选择同期我科收治的95例EB病毒检测阴性的发热患儿（非IM组）和体检健康的73例健康儿童（对照组）。根据是否发生肝损害将IM患儿分为肝损害组（61例）和非肝损害组（41例）。比较外周血NLR、CD4⁺/CD8⁺比值、ADA与EBV-DNA载量,Pearson法分析NLR、CD4⁺/CD8⁺比值、ADA与EBV-DNA载量的相关性。多因素Logistic回归分析IM患儿发生肝损害的影响因素。结果：IM组ADA高于非IM组和对照组（P＜0.05）,且非IM组高于对照组（P＜0.05）,NLR、CD4⁺/CD8⁺比值低于非IM组和对照组（P＜0.05）,且非IM组低于对照组（P＜0.05）,IM组EBV-DNA载量高于非IM组（P＜0.05）。IM患儿ADA与EBV-DNA载量呈正相关（r=0.493,P＜0.05）,NLR、CD4⁺/CD8⁺比值与EBV-DNA载量呈负相关（r=-0.419、-472,P＜0.05）。肝损害组ADA、EBV-DNA载量高于非肝损害组（P＜0.05）,NLR、CD4⁺/CD8+⁺比值低于非肝损害组（P＜0.05）。肝脏肿大、高EBV-DNA载量、高ADA是IM患儿肝损害的危险因素（P＜0.05）,高NLR、高CD4⁺/ CD8⁺比值是保护因素（P＜0.05）。结论：IM患儿ADA增高,NLR、CD4⁺/CD8⁺比值降低,与EBV-DNA载量增加以及肝损害有关。     

高压氧联合低剂量阿替普酶静脉溶栓治疗老年急性缺血性脑卒中的疗效及对患者神经认知功能、凝血指标的影响

摘要 目的：评价高压氧（HBO）联合低剂量阿替普酶（rtPA）静脉溶栓治疗老年急性缺血性脑卒中（AIS）的疗效及对患者神经认知功能、凝血指标的影响。方法：选入我院2020年1月~2022年12月收治的老年AIS患者60例,随机分为对照组和观察组,各30例。对照组予以HBO+标准剂量（0.9 mg/kg）rtPA静脉溶栓治疗,观察组采用HBO+低剂量（0.6 mg/kg）rtPA治疗。评价两组的治疗效果、神经认知功能及凝血指标等,并进行统计比较。结果：两组治疗总有效率无明显差异（P＞0.05）;与溶栓前比较,两组溶栓后24 h、7 d时的NIHSS显著下降、MMSE明显升高（P＜0.05）,但两组之间无明显差异（P＞0.05）;相较于溶栓前,两组溶栓后7 d时PT、APTT、TT、D-D不同程度增加,Fib明显下降（P＜0.05）,而观察组增加/下降幅度较小,与对照组差异显著（P＜0.05）;观察组出血率明显低于对照组（6.67% vs 26.67%,P＜0.05）;两组死亡率无明显差异（P＞0.05）。结论：HBO联合低剂量与标准剂量rtPA静脉溶栓在改善AIS患者神经认知功能、临床疗效及死亡率方面效果相当,但低剂量对血凝功能影响小,同时出血发生风险低。     

特罗凯靶向治疗联合培美曲塞和顺铂对非小细胞肺癌患者血清肿瘤标志物、免疫球蛋白和T淋巴细胞亚群的影响

摘要 目的：探讨特罗凯靶向治疗联合培美曲塞和顺铂对非小细胞肺癌（NSCLC）患者血清肿瘤标志物、免疫球蛋白和T淋巴细胞亚群的影响。方法：选取2018年2月~2020年2月期间我院接收的NSCLC患者80例,采用抽签法分为对照组、观察组两组,各40例。对照组给予培美曲塞和顺铂化疗方案治疗,观察组在对照组基础上联合特罗凯靶向治疗,对比两组总有效率、血清肿瘤标志物、免疫球蛋白、T淋巴细胞亚群及不良反应发生率。结果：对比两组不良反应无差异（P>0.05）。治疗3个疗程后,对照组、观察组的临床总有效率分别为37.50%、60.00%,观察组的总有效率高于对照组（P<0.05）。治疗3个疗程,观察组CD3⁺、CD4⁺、CD4⁺/CD8⁺高于对照组,CD8⁺低于对照组（P<0.05）。治疗3个疗程,观察组免疫球蛋白G（IgG）、免疫球蛋白A（IgA）、免疫球蛋白M（IgM）高于对照组（P<0.05）。治疗3个疗程,观察组细胞角蛋白19片段（CYFRA21-1）、糖类抗原50（CA50）、癌胚抗原（CEA）低于对照组（P<0.05）。结论：特罗凯靶向治疗联合培美曲塞和顺铂治疗NSCLC患者,疗效较好,可能与该方案可降低患者血清肿瘤标志物含量、调节免疫应答等因素有关。     

曲妥珠单抗联合榄香烯注射液治疗乳腺癌的疗效及对血清BNP、cTnⅠ表达的影响

摘要 目的：探究曲妥珠单抗联合榄香烯注射液治疗乳腺癌的疗效及对血清BNP、cTnⅠ表达的影响。方法：2018年2月至2021年6月于我院接受治疗的78例乳腺癌患者,将其按照治疗药物的不同分为观察组（39例）与对照组（39例）,观察组给予曲妥珠单抗联合榄香烯注射液治疗,对照组仅给予曲妥珠单抗注射液治疗,对比两组患者治疗效果、术前术后T淋巴细胞亚群水平、生活质量、毒性反应、血清脑利钠肽（BNP）和高敏心肌肌钙蛋白（cTnⅠ）水平情况。结果：（1）观察组治疗总有效率较对照组高（P<0.05）;（2）观察组毒性反应总发生率为15.38 %显著低于对照组的35.90 %（P<0.05）;（3）治疗后观察组的CD3⁺、CD4⁺水平均较对照组高,CD8⁺水平较对照组低（P<0.05）;（4）治疗后血清cTnⅠ、BNP水平逐渐升高,且每一周期对照组血清cTnⅠ水平高于观察组（P<0.05）。（5）治疗后观察组躯体功能、认知功能、总体健康状况评分显著高于对照组（P<0.05）。结论：曲妥珠单抗联合榄香烯注射液治疗乳腺癌的可行性较好,能显著提高治疗有效率,改善患者的生活质量和免疫功能,同时还能降低血清BNP和cTnⅠ水平,值得临床推广应用。     

rt-PA动脉溶栓联合血管内支架成形术对早期急性脑梗死患者纤溶系统和血清神经功能损伤指标的影响

摘要 目的：探讨重组人组织型纤溶酶原激活物（rt-PA）动脉溶栓联合血管内支架成形术治疗早期急性脑梗死（ACI）的疗效及对纤溶系统和血清神经功能损伤指标的影响。方法：选取我院2018年9月~2021年3月间接收的80例早期ACI患者。根据随机数字表法分为对照组38例（rt-PA动脉溶栓治疗）和研究组42例（rt-PA动脉溶栓联合血管内支架成形术治疗）。对比两组血管再通情况、纤溶系统和血清神经功能损伤指标变化、日常生活能力量表（ADL）及美国国立卫生研究院卒中量表（NIHSS）评分,观察两组预后情况。结果：研究组的血管完全再通率高于对照组（P<0.05）。研究组治疗后1 d、治疗后7 d、治疗后3个月NIHSS评分低于对照组,ADL评分高于对照组（P<0.05）。研究组治疗7 d后血管性假血友病因子（vWF）、血浆纤溶酶原激活物抑制剂-1（PAI-1）低于对照组,组织型纤溶酶原激活剂（tPA）高于对照组（P<0.05）。研究组治疗7 d后胶质纤维酸性蛋白（GFAP）、神经元特异性烯醇化酶（NSE）、S100β蛋白低于对照组（P<0.05）。研究组患者的再发脑梗死率、死亡率低于对照组（P<0.05）。结论：rt-PA动脉溶栓联合血管内支架成形术治疗早期ACI患者,可改善患者近远期疗效和预后,有效调节纤溶系统,减轻机体神经功能损伤,提高患者日常生活能力。     

小儿肺咳颗粒联合头孢呋辛酯治疗急性支气管炎患儿的临床疗效及对免疫功能和炎症指标的影响

摘要 目的：探讨小儿肺咳颗粒联合头孢呋辛酯治疗急性支气管炎患儿的临床疗效及对免疫功能和炎症指标的影响。方法：将我院2019年1月到2020年12月期间接收的88例急性支气管炎患儿以信封抽签法的方式分为对照组（头孢呋辛酯治疗）和观察组（小儿肺咳颗粒联合头孢呋辛酯治疗）,各44例,两组患儿均治疗10 d。观察两组患儿疗效、临床症状消失时间、免疫功能、炎症因子及不良反应。结果：观察组患儿临床总有效率为90.91%（40/44）,高于对照组患儿的70.45%（31/44）（P<0.05）。与对照组相比,观察组的临床症状消失时间（肺部啰音、咳嗽、发热）更短（P<0.05）。治疗10 d后,观察组CD3⁺、CD4⁺、CD4⁺/CD8⁺高于对照组,CD8⁺低于对照组（P<0.05）。治疗10 d后,观察组血清白介素-6（IL-6）、超敏C反应蛋白（hs-CRP）、肿瘤坏死因子-α（TNF-α）水平低于对照组（P<0.05）。两组不良反应发生率组间对比差异无统计学意义（P>0.05）。结论：急性支气管炎患儿在头孢呋辛酯治疗的基础上给予小儿肺咳颗粒治疗,症状缓解时间缩短,同时还可有效降低血清炎症因子水平,提高患儿免疫力,安全可靠。     

CD30/CD30 ligand and CD40/CD40 ligand in malignant lymphoid disorders

CD30 and CD40 are members of the tumor necrosis factor (TNF) receptor family. These two receptors have pleiotropic biologic functions including induction of apoptosis and enhancing cell survival. This review will discuss the pattern of expression of these receptors in malignant lymphoid disorders and their prospective ligands. Understanding issues related to these two ligands and their receptors in lymphoid malignancies may help to improve the classification of these diseases and could open the doors for new treatment strategies.     

Follicular lymphoma intratumoral CD4+CD25+GITR+ regulatory T cells potently suppress CD3/CD28-costimulated autologous and allogeneic CD8+CD25- and CD4+CD25- T cells

Regulatory T cells (T(R)) play a critical role in the inhibition of self-reactive immune responses and as such have been implicated in the suppression of tumor-reactive effector T cells. In this study, we demonstrate that follicular lymphoma (FL)-infiltrating CD8+ and CD4+ T cells are hyporesponsive to CD3/CD28 costimulation. We further identify a population of FL-infiltrating CD4+CD25+GITR+ T(R) that are significantly overrepresented within FL nodes (FLN) compared with that seen in normal (nonmalignant, nonlymphoid hyperplastic) or reactive (nonmalignant, lymphoid hyperplastic) nodes. These T(R) actively suppress both the proliferation of autologous nodal CD8+CD25- and CD4+CD25- T cells, as well as cytokine production (IFN-gamma, TNF-alpha and IL-2), after CD3/CD28 costimulation. Removal of these cells in vitro by CD25+ magnetic bead depletion restores both the proliferation and cytokine production of the remaining T cells, demonstrating that FLN T cell hyporesponsiveness is reversible. In addition to suppressing autologous nodal T cells, these T(R) are also capable of suppressing the proliferation of allogeneic CD8+CD25- and CD4+CD25- T cells from normal lymph nodes as well as normal donor PBL, regardless of very robust stimulation of the target cells with plate-bound anti-CD3 and anti-CD28 Abs. The allogeneic suppression is not reciprocal, as equivalent numbers of CD25+FOXP3+ cells derived from either normal lymph nodes or PBL are not capable of suppressing allogeneic CD8+CD25- and CD4+CD25- T cells, suggesting that FLN T(R) are more suppressive than those derived from nonmalignant sources. Lastly, we demonstrate that inhibition of TGF-beta signaling partially restores FLN T cell proliferation suggesting a mechanistic role for TGF-beta in FLN T(R)-mediated suppression.     

CD2 and CD3 associate independently with CD5 and differentially regulate signaling through CD5 in Jurkat T cells.

In T lymphocytes, the CD2 and CD5 glycoproteins are believed to be involved in the regulation of signals elicited by the TCR/CD3 complex. Here we show that CD2 and CD3 independently associate with CD5 in human PBMC and Jurkat cells. CD5 coprecipitates with CD2 in CD3-deficient cells and, conversely, coprecipitates with CD3 in cells devoid of CD2. In unstimulated CD2+ CD3+ Jurkat cells, CD5 associates equivalently with CD2 and CD3 and is as efficiently phosphorylated in CD2 as in CD3 immune complexes. However, upon activation the involvement of CD5 is the opposite in the CD2 and CD3 pathways. CD5 becomes rapidly tyrosine phosphorylated after CD3 stimulation, but is dephosphorylated upon CD2 cross-linking. These opposing effects correlate with the decrease in the activity of the SH2 domain-containing protein phosphatase 1 (SHP-1) following CD3 activation vs an enhanced activity of the phosphatase after CD2 triggering. The failure of CD5 to become phosphorylated on tyrosine residues in the CD2 pathway has no parallel with the lack of use of zeta-chains in CD2 signaling; contrasting with comparable levels of association of CD2 or CD3 with CD5, zeta associates with CD2 only residually and is nevertheless slightly phosphorylated after CD2 stimulation. The modulation of CD5 phosphorylation may thus represent a level of regulation controlled by CD2 in signal transduction mechanisms in human T lymphocytes.     

Synthesis and CD structural studies of CD52 peptides and glycopeptides

The syntheses of five natural and N-terminal acetylated peptides and glycopeptides of the CD52 antigen are described. Solid phase peptide synthesis was employed in the construction of the target compounds from Fmoc-protected commercial amino acids and synthetic glycan-asparagine conjugates. Circular dichroism studies of the synthetic targets showed that they exist as random coils in solution, and no significant change in secondary structure was observed when the CD52 peptide was either acetylated at the N-terminus or glycosylated at the Asn³ residue with a disaccharide or a fucose-containing branched trisaccharide.     

CD7 and CD28 are required for murine CD4+CD25+ regulatory T cell homeostasis and prevention of thyroiditis

CD7 and CD28 are T cell Ig superfamily molecules that share common signaling mechanisms. To determine roles CD7 and CD28 might play in peripheral lymphocyte development and function, we have generated CD7/CD28-double-deficient mice. CD7- and CD28-single-deficient and CD7/CD28-double-deficient mice had normal levels of CD4 and CD8-single-positive T cells in thymus and spleen. However, CD28-deficient mice had decreased CD4+CD25+ T cells in spleen compared with wild-type mice, and CD7/CD28-double-deficient mice had decreased numbers of CD4+CD25+ T cells in both thymus and spleen compared with both wild-type and CD28-deficient mice. Functional studies demonstrated that CD4+CD25+ T cells from CD28-deficient and CD7/CD28-double-deficient mice could mediate suppression of CD3 mAb activation of CD4+CD25- wild-type T cells, but were less potent than wild-type CD4+CD25+ T regulatory cells. Thyroiditis developed in aged CD7/CD28-double-deficient mice (>1 year) that was not seen in age-matched control mice or single CD7- or CD28-deficient mice, thus suggesting in vivo loss of T regulatory cells allowed for the development of spontaneous thyroiditis. Taken together, these data demonstrated collaborative roles for both CD7 and CD28 in determination of number and function of CD4+CD25+ T regulatory cells in the thymus and peripheral immune sites and in the development of spontaneous thyroiditis.     

Differential Requirement for CD70 and CD80/CD86 in Dendritic Cell-Mediated Activation of Tumor-Tolerized CD8 T Cells

Activated human blood γδ T cells have also been previously demonstrated to behave as professional APCs, although the processes that control APC function have not been characterized. n this study, we show that the acquisition of potent APC function by human blood γδ T cells is achieved after physical interaction with an Ab-coated target cell, a process that we refer to as licensing. In cancer models, licensing of γδ T cells by tumor-reactive mAbs promotes the uptake of tumor Ags and professional presentation to tumor-reactive αβ T cells. We propose that licensing by Ab is a mechanism whereby the adaptive properties of γδ T cells are induced by their innate functions in a spatially and temporally controlled manner.     

Expression of CD16, CD18 and CD56 in tributyltin-exposed human natural killer cells

Tributyltin (TBT) was produced in large quantities for use in wood preservation, marine antifouling paints, disinfection of circulating industrial cooling waters and slime control in paper mills. TBT is found in dairy products, meat and fish. We and others have shown that there are measurable levels of TBT in human blood. BTs appear to increase the risk of cancer and viral infections in exposed individuals. In previous studies, we demonstrated that the NK-cytotoxic function of lymphocytes was greatly diminished after a 1-h exposure to 300 nM TBT or a 24-h exposure to 200 nM TBT. Inhibition induced by a 1-h exposure to 300 nM TBT continues even after removal of the compound. There is also decreased ability of NK cells to bind to tumor target cells when they have been exposed to 200 nM TBT for 24 h. This loss of binding function is not seen when NK cells are exposed to 300 nM TBT for 1 h. However, NK cells exposed to 300 nM TBT for 1 h and then incubated in TBT-free media for 24, 48 or 96 h, show a significant loss of tumor-binding function by 96 h. The effects of TBT on cell surface molecules that are crucial to NK cell function is investigated. The data indicate there is a loss of expression of CD16 and CD56 on NK cells exposed to 200 nM TBT for 24 h. There is no decrease in expression of any of the markers studied when NK cells are exposed to 300 nM TBT for 1 h, consistent with the fact that a 1-h exposure has no effect on the ability of NK cells to bind to tumor targets. However, when NK cells are exposed to 300 nM TBT followed by 24, 48 or 96 h incubations in TBT-free media, there is a significant loss of CD16 and CD18 expression after 24 h and of CD16 and CD56 expression after 48 and 96 h.