ABSTRACT
Los extractos de semillas de 21 variedades de caraota fueron ensayados para determinar la especificidad hemaglutinante y la actividad mitogénica. Entre las diferentes variedades de caraotas se pueden distinguir cuatro tipos, dos de los cuales son mitógenos. Se aislaron dos fracciones de lectinas (α y b) de cada uno de los cuatro tipos de caraotas. Sus PM fueron estimados por cromatografía de exclusión y los azúcares presentes por cromatografía en papel. La actividad hemaglutinante, la inhibición de la acción hemaglutinante por derivados de azúcares y glucopéptidos, así como la acción mitogénica, se determinaron para las ocho lectinas purificadas y las cuatro preparaciones control. Las fracciones α y b aisladas a partir de dos de los tipos de caraotas mostraron solamente acción mitogénica mínima, mientras que las de los otros dos tipos de caraotas y todas las preparaciones control fueron mitógenos potentes. Todas las preparaciones mitogénicas aglutinaron en altas diluciones tanto a los glóbulos rojos de vaca activados con tripsina como a los de hámster activados con pronasa; sin embargo, algunas preparaciones resultaron inactivas cuando se probaron con los glóbulos rojos humanos o de conejo(AU)
Extracts of seeds of 21 bean cultlvars were screened for hemagglutinating specifity and for mitogenic activity. Four types could be distinguished in different beans, two of which are mitogens. Two lectin fractions (a and β) were isolated from each of the four bean types. Their MW were estimated by exclusion chromatography and component sugars by paper chromatography. Hemagglutinating activity, inhibition of hemagglutinating action by sugar-derivatives and glyco-peptides as well as mitogenic action were determined for the eight purified lectins and four control preparations. The a and β-fractions isolated from two bean types had only minimal mitogenic action, while those from the other two bean types and all of the control preparations were potent mitogens. All the mitogenic preparations agglutinated trypsin-activated cow red blood cells and pronase-activated hamster red blood cells in high dilutions but some were inactlve when tested with human or rabbit red blood cells(AU)
Subject(s)
Humans , Animals , Phytohemagglutinins , Phaseolus , Erythrocytes , Lectins , Sensitivity and Specificity , Food HandlingABSTRACT
Objective To study the effects of different stimulators on the production of matrix metalloproteinases (MMPs) by peripheral blood mononuclear cells (PBMCs),and to evaluate the effects of the culture supernatant of activated PBMCs,named conditioned media (CM),on the proliferation of and production of MMPs by cultured human fibroblasts.Methods PBMCs were isolated from the venous blood samples of healthy volunteers and divided into three groups to be stimulated by phytohemagglutinin (PHA group),the combination of antibodies against CD3 and CD28 (double-antibody group),or the RPMI 1640 medium containing 10％ fetal calf serum (control group).After 72-hour stimulation,CM was collected from all the three groups,diluted to several different degrees.Cultured human fibroblasts were classified into several groups to be treated with different dilutions of CM from the three groups for 48 or 24 hours,with the fibroblasts untreated with CM serving as the control group.Methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate cellular proliferative activity,semi-quantitative reverse transcription (RT)-PCR to detect the expressions of MMP-1,MMP-3 and MMP-9 mRNAs in cells,and enzyme-linked immunosorbent assay (ELISA) to measure the levels of interleukin (IL)-6,MMP-1,MMP-3 and MMP-9 proteins in the culture supernatant of cells.Statistical analysis was carried out mainly by using one-way analysis of variance (ANOVA),Tukey HSD test,and GamesHowell test.Results Compared with the control group,the PHA group showed increased cellular proliferative activity,IL-6 and MMP-3 protein levels in the culture supernatant of activated PBMCs (all P ＜ 0.05).Significant differences were observed among the PHA group,double-antibody group and control group in the relative mRNA expression level (expressed as the ratio of target mRNA to β-actin mRNA) of MMP-1 in activated PBMCs (0.083 ± 0.016 vs.0.188 ± 0.030 vs.0.714 ± 0.104,F =85.905,P ＜ 0.05),but neither MMP-3 nor MMP-9 mRNA was expressed by activated PBMCs.MMP-3 protein was detectable in the culture supernatant of fibroblasts after the treatment with CM,and the level of MMP-3 protein was highest in that of fibroblasts treated with undiluted CM,and lowest with 1/10 diluted CM;at the same dilutions,the level of MMP-3 protein was highest in the culture supernatant of fibroblasts treated with CM from the PHA group,but lowest with that from the control group.Neither MMP-1 nor MMP-9 protein was detected in the culture supernatant of activated PBMCs or treated fibroblasts.There were no significant differences in cellular proliferative activity of and mRNA expressions of MMP-1 or MMP-3 in fibroblasts among these groups (all P ＞ 0.05),and MMP-9 mRNA expression was undetected in the treated fibroblasts.Conclusions PBMCs can be induced to express MMP-1 mRNA and secret MMP-3 protein after activation.However,the culture supernatant of activated PBMCs has no capacity to stimulate the expressions of MMP-1,MMP-3 and MMP-9 mRNAs or proteins by fibroblasts,suggesting that inflammatory cells may function through self-production of MMPs.
ABSTRACT
BACKGROUND:Adipose stem cells can differentiate into bone cells, cartilage cells, smooth muscle cells, myocardial cells and nerve cells. Adipose-derived stem cells and mesenchymal stem cells have very similar biological properties, and they are also very close in terms of cellsurface marker expression profile. OBJECTIVE:To investigate the expression of human leukocyte antigen II in adipose-derived stem cells and its immunogenicity and immunomodulatory effect, and to explore the specific mechanism. METHODS:After isolation and culture, the adipose-derived stem cells were stimulated with interferon-γ, and the expression of human leukocyte antigen II was detected by flow cytometry, the expression of indoleamine 2,3-dioxygenase was determined by real-time PCR and western blot. Adipose-derived stem cells were used to stimulate lymphocytes, and the cellproliferation was observed. The lymphocytes were stimulated with phytohemagglutinin, and then 1×102-1×105 adipose-derived stem cells were added to inhibit the proliferation;meanwhile, adipose-derived stem cells, a third party, at a dose of 1×102-1×105 were added to the ongoing two-way mixed lymphocyte reaction, and the cellnumber was calculated as count per minute. RESULTS AND CONCLUSION:The expression of human leukocyte antigen II and indoleamine 2,3-dioxygenase was low in adipose-derived stem cells, but up-regulated with stimulation of interferon-γ. Adipose-derived stem cells could not stimulate lymphocyte proliferation, but could inhibit lymphocyte proliferation induced by phytohemagglutinin or al ogeneic lymphocytes, and interferon-γwas highly expressed in the supernatant of co-culture of adipose-derived stem cells and mixed lymphocytes. These results indicate that the adipose-derived stem cells have low immunogenicity and can inhibit cellproliferation of lymphocytes in vitro, and the addition of exogenous interferon-γcan enhance the immunosuppressive effects of adipose-derived stem cells.
ABSTRACT
Objective: To investigate the expression difference of TRAIL and its receptors between resting and activated peripheral blood lymphocytes, and to study their role in cellular growth and proliferation. Methods: Expression of TRAIL and its receptors were detected by RT PCR and DNA sequencing. Results: Neither the expression of TRAIL nor its receptors were detected in resting peripheral blood lymphocyte. However, both expression were found in activated peripheral blood lymphocytes of various degree. Conclusion: TRAIL and its receptors may play a role in regulation and control of the activated lymphocytes in immune reaction.
ABSTRACT
0 05). The level of IL-12 in PB serum was higher than that of PB serum( P