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991.
992.
Muregi FW Ishih A Miyase T Suzuki T Kino H Amano T Mkoji GM Terada M 《Journal of ethnopharmacology》2007,111(1):190-195
Methanolic extracts from 15 medicinal plants representing 11 families, used traditionally for malaria treatment in Kenya were screened for their in vivo antimalarial activity in mice against a chloroquine (CQ)-tolerant Plasmodium berghei NK65, either alone or in combination with CQ. The plant parts used ranged from leaves (L), stem bark (SB), root bark (RB), seeds (S) and whole plant (W). When used alone, extracts from seven plants, Clerodendrum myricoides (RB), Ficus sur (L/SB/RB), Maytenus acuminata (L/RB), Rhamnus prinoides (L/RB), Rhamnus staddo (RB), Toddalia asiatica (RB) and Vernonia lasiopus (RB) had statistically significant parasitaemia suppressions of 31.7-59.3%. In combination with CQ, methanolic extracts of Albizia gummifera (SB), Ficus sur (RB), Rhamnus prinoides and Rhamnus staddo (L/RB), Caesalpinia volkensii (L), Maytenus senegalensis (L/RB), Withania somnifera (RB), Ekebergia capensis (L/SB), Toddalia asiatica (L/RB) and Vernonia lasiopus (L/SB/RB) gave statistically significant and improved suppressions which ranged from 45.5 to 85.1%. The fact that these activities were up to five-fold higher than that of extract alone may suggest synergistic interactions. Remarkable parasitaemia suppression by the extracts, either alone or in combination with CQ mostly resulted into longer mouse survival relative to the controls, in some cases by a further 2 weeks. Plants, which showed significant antimalarial activity including Vernonia lasiopus, Toddalia asiatica, Ficus sur, Rhamnus prinoides and Rhamnus staddo warrant further evaluation in the search for novel antimalarial agents against drug-resistant malaria. 相似文献
993.
994.
Stefano Lazzi MD PhD Cristiana Bellan MD PhD Anna Onnis PhD Giulia De Falco PhD Shahin Sayed PhD Ioannis Kostopoulos MD Monica Onorati MD Alessandro D'Amuri MD Rosa Santopietro MD Carla Vindigni MD Alberto Fabbri MD Simona Righi PhD Stefano Pileri MD Piero Tosi MD Lorenzo Leoncini MD 《Human pathology》2009,40(9):1252-1261
995.
目的 用5-氟尿嘧啶(5-fluorouracil,5-FU)处理HeLa细胞,检测其NKG2D 配体 MICA 的表达及其对NK92细胞杀伤敏感性的变化.方法 不同浓度的 5-FU处理 HeLa细胞,在不同时间点用半定量PCR及流式细胞术检测HeLa细胞表面的NKG2D配体MICA在RNA及蛋白水平的表达变化情况,用MTT法检测NKG2D抗体封闭NK92细胞的NKG2D受体前后, NK92 细胞对HeLa细胞的杀伤作用.结果 不同浓度的5-FU作用于 HeLa 细胞后,半定量RT-PCR结果显示MICA表达随5-FU作用浓度增加逐渐增高.而且40 μg/ml 5-FU作用于HeLa细胞后随着作用时间的延长(0、8、16、24 h)MICA表达增加,流式细胞术检测结果表明,MICA表达的增加主要依赖于未凋亡细胞的 MICA表达.在40μg/ml 5-FU作用24 h,效靶比为2.5∶ 1,5∶ 1,10∶ 1,20∶ 1时都检测到NK92细胞对HeLa细胞的杀伤增强,杀伤作用可部分被NKG2D抗体抑制.结论 5-FU 能够上调HeLa细胞表面NKG2D配体MICA的表达,增强HeLa细胞对NK92细胞的敏感性,提示化疗联合NK细胞免疫治疗宫颈癌可产生协同作用,提高治疗效果. 相似文献
996.
Maria Alice Sant'Anna Zarife Eliana Almeida Gomes Reis Theomira Mauadie Azevedo Carmo Gisele Barreto Lopes Emilia Carolina Malafaia Brando Helder Reis Silva Nelma Santana Olindo Assis Martins‐Filho Mitermayer Galvo Reis 《Journal of medical virology》2009,81(1):49-59
A detailed phenotypic analysis of major and minor circulating lymphocyte subsets is described in potential blood donors with markers of hepatitis C virus (HCV), including non‐viremic and viremic groups. Although there were no changes in the hematological profile of either group, increased the levels of pre‐NK cells (CD3?CD16+CD56?) and a lower frequency of mature NK cells (CD3?CD16+CD56+) characterized innate immunity in the non‐viremic group. Both non‐viremic and viremic groups displayed significantly increased levels of CD56Bright NK cells. Furthermore, this subset was significantly elevated in the viremic subgroup with a low viral load. In addition, an increase in the NKT2 subset was observed only in this subgroup. An enhanced frequency of activated CD4+ T‐cells (CD4+HLA‐DR+) was a characteristic feature of the non‐viremic group, whereas elevated CD19+ B‐cells and CD19+CD86+ cell populations were the major phenotypic features of the viremic group, particularly in individuals with a low viral load. Although CD4+CD25High T‐cells were significantly elevated in both the viremic and non‐viremic groups, it was particularly evident in the viremic low viral load subgroup. A parallel increase in CD4+CD25High T‐cells, pre‐NK, and activated CD4+ T‐cells was observed in the non‐viremic group, whereas a parallel increase in CD4+CD25High T‐cells and CD19+ B‐cells was characteristic of the low viral load subgroup. These findings suggest that CD56Bright NK cells, together with pre‐NK cells and activated CD4+ T‐cells in combination with CD4+CD25High T‐cells, might play an important role in controlling viremia. Elevated CD56Bright NK cells, B‐cell responses and a T‐regulated immunological profile appeared to be associated with a low viral load. J. Med. Virol. 81:49–59, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
997.
Junji Tanaka Junichi Sugita Shinsuke Asanuma Kotaro Arita Yusuke Shono Misato Kikutchi Souichi Shiratori Kentaro Wakasa Atsushi Yasumoto Akio Shigematu Takeshi Kondo Takahiko Kobayashi Masahiro Asaka Masahiro Imamura 《Human immunology》2009,70(9):701-705
In the present study, we investigated subpopulations of natural killer (NK) cells and the expression of stimulatory and inhibitory NK receptors after adult blood and bone marrow transplantation (BBMT) and cord blood transplantation (CBT). There were significant increases in CD16+CD56dim cell proportion and in absolute number in peripheral blood mononuclear cells (PBMC) during a period of 4–9 months after CBT compared with these in normal PBMC, cord blood (CB), and in PBMC after BBMT. Also, increased numbers of CD16+CD56dim NK cells were sustained in some patients until 4 years after CBT. This CD16+CD56dim cell subset after CBT exhibited decreased expression of NKG2A compared with that in CB and increased expression of NKG2C. Purified CD16+CD56dim cells from patients 8–9 months after CBT exhibited significantly higher levels of cytolytic activity against K562 than did purified CD16+CD56bright cells and also whole PBMC. The CD16+CD56dim cell subset with a high level of cytolytic activity significantly increased after CBT, and these cells may be responsible for NK cell–mediated immunity after CBT. 相似文献
998.
Introduction In recent years, it has been realized that innate lymphocytes do not act in isolation but potentiate their efficiency by interacting
with each other, resulting even in the regulation of adaptive immune response. One such cross-talk exists between dendritic
cells (DCs) and natural killer (NK) cells. Here, we summarize recent studies on which subsets of these two innate immune components
participate in this interaction, how it influences immune responses, and to which extent similar stimuli are integrated by
DCs and NK cells during innate immunity.
Conclusion We suggest that this cross-talk should be harnessed by activating both of these innate leucocyte populations with new adjuvant
formulations for immunotherapies. 相似文献
999.
1000.
Aoki I Takahashi Y Chuang KH Silva AC Igarashi T Tanaka C Childs RW Koretsky AP 《NMR in biomedicine》2006,19(1):50-59
There is growing interest in using MRI to track cellular migration. To date, most work in this area has been performed using ultra-small particles of iron oxide. Immune cells are difficult to label with iron oxide particles. The ability of adoptively infused tumor specific T cells and N cells to traffic to the tumor microenvironment may be a critical determinant of their therapeutic efficacy. We tested the hypothesis that lymphocytes and B cells would label with MnCl2 to a level that would allow their detection by T1-weighted MRI. Significant signal enhancement was observed in human lymphocytes after a 1 h incubation with 0.05-1.0 mM MnCl2. A flow cytometry-based evaluation using propidium iodide and Annexin V staining showed that lymphocytes did not undergo apoptosis or necrosis immediately after and 24 h following a 1 h incubation with up to 1.0 mM MnCl2. Importantly, NK cells and cytotoxic T cells maintained their in vitro killing capacity after being incubated with up to 0.5 mM MnCl2. This is the first report to describe the use of MnCl2 to label lymphocytes. Our data suggests MnCl2 might be an alternative to iron oxide cell labeling for MRI-based cell migration studies. 相似文献