Comparative analysis of accumulation of chlorine e6 and hematoporphyrin derivatives in subpopulations of peripheral blood lymphocytes

We studied accumulation of porphyrin photosensitizers chlorine e6, hematoporphyrin, and their derivatives by different lymphocyte subpopulations. The intensity of staining of B lymphocytes and natural killer cells with photosensitizers was higher compared to T lymphocytes. T cell subpopulation differed by their ability to bind photosensitizers. Relative accumulation of dimethyl esters of chlorine e6 and hematoporphyrin in cells surpassed that of nonesterified porphyrins. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 8, pp. 180–184, August, 2004 Thisk work was supported by the Belarussian-Russian Foundation for Basic Research (grant NO. B02R-084).     

Neural stem/progenitor cells damaged by reactive oxygen species evolved in photosensitizing reaction

We want to know how the growth of neural stem/progenitor cells and their differentiation are affected by reactive oxygen species evolved in photosensitizing reaction, because of the similarity between the stem cells and the tumor cells in central nervous system. We investigated the effects of two photosensitizers (rhodamine 123 and hematoporphyrin) on the mouse neural stem/progenitor cells cultured in vitro under the illumination. ABC transporters were expressed in the cells, and could pump rhodamine 123 and hematoporphyrin out of the cells. Under the illumination of strong actinic light with those photosensitizers, reactive oxygen species was evolved to injure the cells. Number of viable cells decreased under illumination through apoptosis and necrosis. Those cell-killing activities were not clearly dependent on the presence of inhibitors for ABC transporters. Immunocytochemical staining with showed that immature cells with markers of neural stem/progenitor cells (Sox 2, CD133, nestin) were more sensitive to the reactive oxygen species than the differentiated cells.     

Assessment of laboratory and field assays of sunlight-induced killing of mosquito larvae by photosensitizers

The effectiveness of light-induced killing of mosquito larvae in the presence of photosensitizers was studied with larvae of Aedes aegypti (L.), Anopheles stephensi (Liston), and Culex quinquefasciatus Say grown in the laboratory and of Cx. quinquefasciatus grown under field conditions. Tested photosensitizers included xanthene, chlorin, and porphyrin derivatives. All the larvae were treated at the fourth instar. Preliminary laboratory experiments showed a light-induced lethal effect of Rose Bengal (RB) on three species of mosquito larvae. Compared with other photosensitizers, RB seemed to be more efficient at even lower concentration than chlorin (e6) and chlorophyllin on Ae. aegypti larvae. Among the four porphyrin derivatives, i.e., chloroquinoline tetraphenyl propioamidoporphine, tetraphenyl porphine tetrasulfonate, hematoporphyrin (HP), and tetraphenylporphinepropionic acid porphine, HP was the only effective photosensitizer on Ae. aegypti larvae. The best conditions for field tests using RB were conducted on Cx. quinquefasciatus in Bobo-Dioulasso, Burkina Faso. The mortality induced by RB varied from 80 to 96% obtained with unfiltered cesspit water to 0.4 to 6.7% in cesspits with a heavy load of organic materials, thus providing the basis for further developments of this technique under field conditions.     

CCL25 induces α₄β₇ integrin-dependent migration of IL-17⁺ γδ T lymphocytes during an allergic reaction

Herein, we provide evidence that during allergic inflammation, CCL25 induces the selective migration of IL-17(+) γδ T cells mediated by α(4) β(7) integrin. Intrapleural injection of CCL25 into ovalbumin (OVA)-immunized C57BL/6 mice triggered the accumulation of γδ T lymphocytes expressing CCR9 (CCL25 receptor) and α(4) β(7) integrin in the pleura, but failed to attract αβ T lymphocytes. CCL25 attracted CCR6(+) γδ T cells producing IL-17 (but not IFN-γ or IL-4). OVA challenge triggered increased production of CCL25 followed by the accumulation of CCR9(+) , α(4) β(7) (+) , and CCR6(+) /IL-17(+) γδ T cells into the pleural cavities of OVA-immunized mice, which was inhibited by the in vivo neutralization of CCL25. The in vivo blockade of α(4) β(7) integrin also inhibited the migration of IL-17(+) γδ T lymphocytes (but not of αβ T lymphocytes) into mouse pleura after OVA challenge, suggesting that the CCL25/α(4) β(7) integrin pathway is selective for γδ T cells. In addition, α(4) β(7) integrin blockade impaired the in vitro transmigration of γδ T cells across endothelium (which expresses α(4) β(7) ligands VCAM-1 and MadCAM-1), which was induced by CCL25 and by cell-free pleural washes recovered from OVA-challenged mice. Our results reveal that during an allergic reaction, CCL25 drives IL-17(+) γδ T-cell mobilization to inflamed tissue via α(4) β(7) integrin and modulates IL-17 levels.     

研究不同光敏剂诱导的光动力疗法对人白血病细胞的杀伤作用

目的 研究并比较3种卟啉类光敏剂——血卟啉衍生物(HpD)、癌光啉(PsD007)和血卟啉 单甲醚(HMME)诱导的光动力疗法(PDT)对白血病细胞K562的杀伤效应.方法 以人白血病细胞K562为研究对象,分为对照组和PDT组,以梯度浓度的光敏剂与K562细胞共同孵育,经不同能量光照后,用噻唑蓝(MTT)法测定PDT对K562细胞的杀伤作用.结果 与对照组相比,PDT对K562细胞有明显杀伤作用,并随着光敏剂浓度的增加和光照能量的增大,效果增强.PsD007-PDT和HMME-PDT的效果都明显优于HpD-PDT(P＜0.05);而当光敏剂质量浓度较大(25 μg/ml)或能量密度较大(7.2 J/cm2)时,PsD007-PDT的作用效果优于HMME-PDT.结论 PDT对人白血病细胞K562具有明显的杀伤作用,其对细胞的抑制率具有显著的剂量效应关系;PDT对K562的杀伤效应与光敏剂种类有关,HpD-PDT的杀伤效果不如PsD007和HMME;在较高能量密度和较大光敏剂浓度的条件下,PsD007-PDT的效果优于HMME-PDT.     

OPN promotes survival of activated T cells by up-regulating CD44 in patients with oral lichen planus

Oral lichen planus (OLP) is a chronic inflammatory disorder of oral mucosa, which represents cell-mediated autoimmune diseases. Pathological study demonstrated that abundant T lymphocytes infiltrated the oral mucosa, in which the activated T cells that trigger apoptosis of oral epithelial cells is an important mechanism for OLP. However, to date the molecular mechanisms underlying the T lymphocytes infiltration and accumulation in OLP remain unclear. In this paper, we found that the levels of plasma OPN were elevated and were associated with the up-regulated expressions of CD44 in OLP patients. In vitro, the addition of exogenous OPN can suppress the apoptosis of activated CD8(+) T cells via CD44, and this T cell resistance to apoptosis may be attributed to the reduction of endogenous mature granzyme B. Our results suggested that the abnormally elevated levels of OPN may contribute to the abnormal infiltration and accumulation of the activated T cells by up-regulating CD44 in OLP.     

Migration Pattern of Lymphocyte Subsets in the Normal Rat and the Influence of Splenic Tissue

Lymphocyte subsets leave the blood and appear in the thoracic duct of normal rats at different rates. The aim of the present study was to investigate their migration pattern through blood, spleen, bone marrow, mesenteric lymph nodes, and Peyer's patches in normal Lewis rats and to study the role of the spleen using splenectomized and spleen-transplanted animals. Fluorescein isothiocyanate (FITC)-labelled thoracic duct lymphocytes (TDL) were injected intravenously into rats and after 15 min, 1, 6, and 24 h the percentages of B, T, T helper (TH) and T-cytotoxic/suppressor (TC/S) lymphocytes in the FITC+ cells were determined in cell suspensions by means of monoclonal antibodies. B and T lymphocytes are preferentially localized in different organs, e.g. B cells in Peyer's patches and T cells in mesenteric lymph nodes. The migration of TH lymphocytes differed from that of TC/S lymphocytes in all the organs investigated. In the late phase after injection the migration of B and TH lymphocytes was influenced by the spleen, since after splenectomy the number of injected B lymphocytes increased and that of TH lymphocytes decreased in all organs investigated except the bone marrow. Splenic autotransplantation could not normalize the disturbed migration.     

Density gradient electrophoresis of mouse spleen lymphocytes. Differential mobilities of macrophages, responding and stimulating cells in mixed lymphocyte culture

Preparative density gradient electrophoresis has been employed for the separation of BALB/c mouse spleen T and B lymphocytes, on the basis of their surface charge. The high mobility cells were found to be predominantly T lymphocytes, whereas the low mobility cells were B lymphocytes. One way mixed lymphocyte cultures were prepared using electrophoretically separated BALB/c lymphocytes, either as responding or stimulating cells and unfractionated CBA/H/T6j mouse spleen lymphocytes, in the appropriate combination. The responding lymphocytes were found only among the high mobility cells which are primarily T lymphocytes. In contrast, the stimulating cells were found in the intermediate and low mobility fractions which contain the B lymphocytes and macrophages. Minimal stimulation in mixed lymphocyte culture was observed by T cells in this allogeneic system. Ia-positive cells were found only in the intermediate and low mobility fractions, which exhibited the capacity to stimulate allogeneic cells in MLC. Macrophages, identified by nonspecific esterase staining, exhibited intermediate electrophoretic mobility, their peak height coinciding with the maximum observed stimulation.     

LDH isoenzyme distribution in human T gamma lymphocytes

The lactate dehydrogenase (LDH) isoenzyme distribution was measured in T gamma+ lymphocytes from normal individuals. T gamma+ lymphocytes were obtained from purified T lymphocytes by ox-IgG rosette sedimentation. The B:A subunit ratio was clearly lower in the T gamma+ lymphocytes. Phenotyping of the T gamma+ lymphocytes showed a vast majority of OKT11+, OKM1+, OKT3- lymphocytes. In one experiment, T gamma+ lymphocytes were enriched by OKT3 depletion of T lymphocytes. The low B:A ratio was also found in these cells indicating that the LDH pattern is not the consequence of an in vitro activation by immune complexes. As the T gamma+ lymphocytes were considerably enriched in cells having the characteristics of NK cells according to their phenotyping, morphology and NK cell activity, we may assume that NK cells have a low B:A ratio.     

Clinicopathological and immunohistochemical studies of xanthogranulomatous cholecystitis--possible pathogenetic role of cell mediated immunity

Clinicopathological and immunohistochemical studies were performed on 22 cases of xanthogranulomatous cholecystitis (XGC). Incidence of XGC was 3.6% of surgically resected gallbladder diseases. All cases of XGC were associated with cholelithiasis in which cholesterol gallstones were 6 times as many as pigment ones. XGC was frequently accompanied by incarceration of gallstones. In cholecystography, two-thirds of gallbladders were not visualized. Histologically, the granulomatous lesion of XGC consisted of accumulations of foam cells, lymphocytes, variable numbers of giant cells, granulocytes and fibroblastic cells. Although there had been no established theory in relation to the origin of foam cells, it is considered that foam cells were derived from monocyte/macrophages because they reacted variably with lysozyme, alpha 1-antichymotrypsin and alpha 1-antitrypsin, and almost invariably with OKM 1 and EBM 11 antibodies. Interspersed among macrophage foam cells, many T lymphocytes were identified. In terms of T cell subsets, CD 8 positive lymphocytes outnumbered CD 4 positive lymphocytes. Electron microscopy demonstrated intimate apposition of T lymphocytes to macrophages or macrophage foam cells. HLA-DR was expressed by most macrophages, macrophage foam cells and T lymphocytes. In conclusion, the results suggest that the features of XGC are those of granulomatous inflammation characterized by accumulation of macrophages, macrophage derived foam cells and activated T cells. It is suggested that delayed type hypersensitivity reaction of cell mediated immunity is operative in the pathogenesis of XGC.