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British Medical Journal (Clinical... Feb 1985
Topics: Animals; Food Analysis; Humans; Lectins; Lymphocyte Activation; Phytohemagglutinins
PubMed: 3918681
DOI: 10.1136/bmj.290.6468.584 -
The Journal of Clinical Investigation Feb 1980Factors influencing basophil production from the bone marrow of ovalbumin (OA)-sensitized guinea pigs have been examined in vitro. Autologous co-cultures of marrow and...
Factors influencing basophil production from the bone marrow of ovalbumin (OA)-sensitized guinea pigs have been examined in vitro. Autologous co-cultures of marrow and spleen cells from OA-immune animals contained significantly higher numbers of basophils after 7 d of liquid culture in the presence of OA, compared with control co-cultures or with marrow cultures alone (P < 0.005). Basophils increased in co-culture as the number of spleen cells added to a fixed number of marrow cells was increased from 0.10 to 2.5 x 10(6)/ml; at each spleen cell concentration, the presence of OA significantly enhanced basophil production in vitro when compared with unstimulated co-cultures. There was no basophil production from spleen cell suspensions cultured in the absence of autologous marrow cells. Conditioned media (CM) prepared from OA-stimulated spleen cells of OA-treated animals (CM-OA) caused a specific stimulation of basophil production from normal guinea pig bone marrow cells in liquid cultures (P < 0.01). Phytohemagglutinin (PHA)- and pokeweed mitogen-stimulated CM (CM-PHA, CM-pokeweed mitogen) nonspecifically enhanced normal basophilopoiesis, causing dose-dependent increases in basophils and histamine in vitro. CM-OA and CM-PHA also preferentially stimulated formation of neutrophil-macrophage colony-forming units in semisolid methylcellulose cultures.CM-PHA prepared from T cell-enriched splenic cell suspensions contained basophil-stimulating activity, whereas T cell-depleted CM-PHA activity did not exceed control values (P < 0.01). Preliminary characterization of CM-PHA revealed that basophil-stimulating activity was predominantly heat stable and nondialyzable. These results demonstrate OA-specific, as well as mitogen-dependent T-cell regulation of guinea pig basophilopoiesis in vitro. The data are compatible with the existence of a specific "basophilopoietin" in CM derived from guinea pig splenic T cells.
Topics: Animals; Basophils; Bone Marrow Cells; Cell Communication; Colony-Forming Units Assay; Culture Media; Guinea Pigs; Hematopoiesis; Histamine; In Vitro Techniques; Mitogens; Ovalbumin; Phytohemagglutinins; Spleen; T-Lymphocytes
PubMed: 6965379
DOI: 10.1172/JCI109682 -
Journal of Molecular Endocrinology Jun 2021Despite all modern advances in medicine, there are few reports of effective and safe drugs to treat obesity. Our objective was to screen anti-obesity natural compounds,...
Despite all modern advances in medicine, there are few reports of effective and safe drugs to treat obesity. Our objective was to screen anti-obesity natural compounds, and to verify whether they can reduce the body weight gain and investigate their molecular mechanisms. By using drug-screening methods, Phytohemagglutinin (PHA) was found to be the most anti-obesity candidate natural compound. Six-week-old C57BL/6J mice were fed with a high-fat diet (HFD) and intraperitoneally injected with 0.25 mg/kg PHA everyday for 8 weeks. The body weight, glucose homeostasis, oxygen consumption and physical activity were assessed. We also measured the heat intensity, body temperature and the gene expression of key regulators of energy expenditure. Prevention study results showed PHA treatment not only reduced the body weight gain but also maintained glucose homeostasis in HFD-fed mice. Further study indicated energy expenditure and uncoupling protein 1 (UCP-1) expression of brown adipose tissue (BAT) and white adipose tissue (WAT) in HFD-fed mice were significantly improved by PHA. In the therapeutic study, a similar effect was observed. PHA inhibited lipid droplet formation and upregulated mitochondrial-related gene expression during adipogenesis in vitro. UCP-1 KO mice displayed no differences in body weight, glucose homeostasis and core body temperature between PHA and control groups. Our results suggest that PHA prevent and treat obesity by increasing energy expenditure through upregulation of BAT thermogenesis.
Topics: Adipose Tissue, Brown; Adipose Tissue, White; Animals; Biological Products; Cell Differentiation; Diet, High-Fat; Energy Metabolism; Glucose; Homeostasis; Male; Mice, Inbred C57BL; Mice, Knockout; Obesity; Phytohemagglutinins; Thermogenesis; Uncoupling Protein 1; Weight Gain; Mice
PubMed: 33983894
DOI: 10.1530/JME-20-0349 -
Journal of Cellular and Molecular... Feb 2022Immunotherapy is an attractive approach for treating cancer. T-cell engagers (TCEs) are a type of immunotherapy that are highly efficacious; however, they are challenged...
Immunotherapy is an attractive approach for treating cancer. T-cell engagers (TCEs) are a type of immunotherapy that are highly efficacious; however, they are challenged by weak T-cell activation and short persistence. Therefore, alternative solutions to induce greater activation and persistence of T cells during TCE immunotherapy is needed. Methods to activate T cells include the use of lectins, such as phytohemagglutinin (PHA). PHA has not been used to activate T cells in vivo, for immunotherapy, due to its biological instability and toxicity. An approach to overcome the limitations of PHA while also preserving its function is needed. In this study, we report a liposomal PHA which increased PHA stability, reduced toxicity and performed as an immunotherapeutic that is able to activate T cells for the use in future cancer immunotherapies to circumvent current obstacles in immunosuppression and T-cell exhaustion.
Topics: Humans; Immunotherapy; Lymphocyte Activation; Neoplasms; Phytohemagglutinins; T-Lymphocytes
PubMed: 35014164
DOI: 10.1111/jcmm.16885 -
Frontiers in Immunology 2018Extrapulmonary tuberculosis (EPTB) has become more common in recent years; however, the diagnosis of EPTB remains a challenge. In this study, we analyzed the performance...
Extrapulmonary tuberculosis (EPTB) has become more common in recent years; however, the diagnosis of EPTB remains a challenge. In this study, we analyzed the performance of the ratio of TB-specific antigen (TBAg) to phytohemagglutinin (PHA) (TBAg/PHA ratio) in T-SPOT.TB (T-SPOT) assay for diagnosis and treatment monitoring of EPTB. Between 2012 and 2017, 734 EPTB patients were diagnosed and recruited from Tongji hospital, and 1,137 suspected EPTB patients who had other diagnoses were recruited as non-EPTB controls. To validate the study, another small group of EPTB patients and non-EPTB controls were recruited from Sino-French New City Branch of Tongji Hospital. The positive rate of peripheral blood T-SPOT in EPTB and non-EPTB were 88.15 and 32.28%. In T-SPOT positive patients, the direct T-SPOT results had limited value in distinguishing these two conditions. A further calculation of the TBAg/PHA ratio of T-SPOT showed improved performance in each form of EPTB. If using 0.20 as the threshold value of the TBAg/PHA ratio, the pooled sensitivity and specificity were 70.79 and 91.55% in distinguishing EPTB from non-EPTB. The validation results showed a better performance of the TBAg/PHA ratio in distinguishing these two conditions, with a sensitivity and specificity of 81.82 and 97.56%, respectively. Comparing with directly using T-SPOT results, the TBAg/PHA ratio was less affected by immunosuppression. Furthermore, PHA value reflected immunosuppression and could help to judge the credibility of T-SPOT results in EPTB patients with different immune status. The TBAg/PHA ratio was significantly decreased during anti-tuberculosis (TB) treatment, which suggests that it can also be used to monitor therapeutic efficacy. These data provide new insights into the role of T-SPOT assay in TB disease, and the TBAg/PHA ratio might be a useful tool for diagnosis and treatment monitoring of EPTB.
Topics: Adult; Antigens, Bacterial; Female; Humans; Interferon-gamma Release Tests; Male; Middle Aged; Mycobacterium tuberculosis; Phytohemagglutinins; Sensitivity and Specificity; Tuberculosis
PubMed: 29868010
DOI: 10.3389/fimmu.2018.01047 -
BMC Psychiatry Mar 2023Based on its objective characteristics, laboratory markers have always been the research direction of clinical diagnosis and assessment of mental disorders including...
BACKGROUND
Based on its objective characteristics, laboratory markers have always been the research direction of clinical diagnosis and assessment of mental disorders including Alzheimer's disease.
METHODS
MTT Colorimetric Assay, ELISA, and quantitative PCR were used to investigate the responsiveness of peripheral blood mononuclear cells (PBMCs) to mitogen Lipopolysaccharides (LPS) and Phytohemagglutinin (PHA), PBMCs genomic methylation and hydroxymethylation levels, nuclear DNA and mitochondrial DNA damage, respiratory chain enzyme activities, and circulating cell-free mitochondrial DNA levels were detected in 90 patients with Alzheimer's disease.
RESULTS
In the Alzheimer's disease group, LPS stimulated PBMCs viability, TNF-α secretion, PHA stimulated IL-10 secretion, genomic DNA methylation levels, circulating cell-free mitochondrial DNA copies, citrate synthase activity were reduced compared to the control; while the LPS stimulated PBMCs IL-1α secretion, PHA stimulated IL-1α and IFN-γ secretion, plasma IL-6 and TNF-α, mitochondrial DNA damages were increased compared to the control.
CONCLUSIONS
The reactivity of peripheral blood mononuclear cells to mitogens, mitochondrial DNA integrity characteristics, and cell-free mitochondrial DNA copies may be used as candidate laboratory biomarkers to help clinical management of Alzheimer's disease.
Topics: Humans; Mitogens; Lipopolysaccharides; Leukocytes, Mononuclear; Tumor Necrosis Factor-alpha; Cytokines; DNA, Mitochondrial; Alzheimer Disease; Phytohemagglutinins
PubMed: 36890488
DOI: 10.1186/s12888-023-04634-x -
Disease Markers 2022The lymphocyte transformation test is a classical test for the detection of cellular immune function and is based on subjective judgment. In this study, we have...
OBJECTIVE
The lymphocyte transformation test is a classical test for the detection of cellular immune function and is based on subjective judgment. In this study, we have established an objective novel lymphocyte transformation test using the hematology analyzer to observe lymphocyte transformation.
METHODS
Whole blood cells were cultured using a whole blood method with a lymphocyte culture medium; phytohemagglutinin was used to stimulate the experimental samples, and control was set up at the same time. After the whole blood cells were cultured, the number of lymphocytes in the two groups was observed using a hematology analyzer, and the conversion rate was calculated. The new method was used to observe differences in lymphocyte conversion in the peripheral blood of patients with hematopathy and healthy persons.
RESULTS
There were significant differences between the stimulated peripheral blood group and the blank group. The transformation rate of peripheral blood lymphocytes in patients with hematopathy was significantly lower than that in healthy persons; the difference was statistically significant ( < 0.05).
CONCLUSION
Lymphocyte transformation can be observed using a hematology analyzer. The lymphocyte transformation test that is based on the determination of lymphocyte count by a hematology analyzer has important clinical value.
Topics: Humans; Phytohemagglutinins; Lymphocyte Activation; Lymphocytes; Lymphocyte Count; Hematology
PubMed: 36393975
DOI: 10.1155/2022/5967429 -
Immunobiology Jan 2019Tumors may include a high proportion of immune modulatory cells and molecules that restrain the anti-cancer response. Activation of T cells to eliminate cancer cells...
Tumors may include a high proportion of immune modulatory cells and molecules that restrain the anti-cancer response. Activation of T cells to eliminate cancer cells within the immune-suppressive tumor microenvironment remains a challenge. We have shown that C57BL/6 J peritoneal cell culture models features of macrophage-dense tumors as TCR ligation fails to activate T cells unless IFNγ is neutralized or iNOS is inhibited. We tested other forms of T cell activation and found phytohemagglutinin (PHA) distinctive in the ability to markedly expand CD8 T cells in this model. IFNγ or iNOS inhibition was not necessary for this response. PHA triggered less IFNγ production and inhibitory PD-L1 expression than TCR ligation. Macrophages and CD44 T cells bound PHA. Spleen T cell responses to PHA were markedly enhanced by the addition of peritoneal cells revealing that macrophages enhance T cell expansion. That PHA increases CD8 T cell responses within macrophage-dense culture suggests this mitogen might enhance anti-tumor immunity.
Topics: Animals; B7-H1 Antigen; CD8-Positive T-Lymphocytes; Cell Proliferation; Cells, Cultured; Immune Tolerance; Interferon-gamma; Lymphocyte Activation; Macrophages, Peritoneal; Mice; Mice, Inbred C57BL; Neoplasms; Phytohemagglutinins; Tumor Escape; Tumor Microenvironment
PubMed: 30446337
DOI: 10.1016/j.imbio.2018.10.004 -
Journal of Animal Science Aug 2021Disease resilience refers to the productivity of an animal under disease. Given the high biosecurity of pig nucleus herds, traits that can be measured on healthy pigs...
Disease resilience refers to the productivity of an animal under disease. Given the high biosecurity of pig nucleus herds, traits that can be measured on healthy pigs and that are genetically correlated with disease resilience, that is, genetic indicator traits, offer a strategy to select for disease resilience. Our objective was to evaluate mitogen stimulation assays (MSAs) on peripheral blood mononuclear cells (PBMCs) from young healthy pigs as genetic indicators for disease resilience. Data were from a natural disease challenge in which batches of 60 or 75 naïve Yorkshire × Landrace piglets were introduced every 3 wk into a continuous flow barn that was seeded with multiple diseases. In this environment, disease resilience traits, including growth, treatment, and mortality rates, were recorded on 3,136 pigs that were genotyped with a high-density marker panel. PBMCs from 882 of these pigs from 19 batches were isolated from whole blood collected prior to the disease challenge and stimulated with five mitogens: concanavalin A (ConA), phytohemagglutinin (PHA), pokeweed mitogen (PWM), lipopolysaccharide (LPS), and phorbol myristate acetate (PMA). The proliferation of cells was evaluated at 48, 72, and 96 h and compared with unstimulated samples (rest count). Heritabilities of cell proliferation were estimated using a model with batch as a fixed effect and covariates of entry age; rest count; complete blood count proportions of lymphocytes, monocytes, eosinophils, and basophils; and pen, litter, and animal genetics as random effects. Heritability estimates were highest for response to ConA (0.30 ± 0.09, 0.28 ± 0.10, 0.17 ± 0.10, and 0.25 ±0.10 at 48, 72, and 96 h after stimulation and for area under the curve across the three time points, respectively). Estimates were in a similar range for response to PHA and PMA but low for PWM and LPS. Responses to ConA, PHA, and PMA were moderately genetically correlated with several disease resilience traits and in the expected direction, but individual estimates were not significantly different from zero due to large SEs. In conclusion, although validation is needed, MSAss, in particular based on ConA, show promise as genetic indicator traits for disease resilience.
Topics: Animals; Cell Proliferation; Leukocytes, Mononuclear; Lymphocyte Activation; Mitogens; Phytohemagglutinins; Pokeweed Mitogens; Swine
PubMed: 33944943
DOI: 10.1093/jas/skab084 -
The Journal of Infection Jul 2020Distinguishing between active tuberculosis (ATB) and latent tuberculosis infection (LTBI) remains challenging.
Combination of mean spot sizes of ESAT-6 spot-forming cells and modified tuberculosis-specific antigen/phytohemagglutinin ratio of T-SPOT.TB assay in distinguishing between active tuberculosis and latent tuberculosis infection.
OBJECTIVES
Distinguishing between active tuberculosis (ATB) and latent tuberculosis infection (LTBI) remains challenging.
METHODS
The modified T-SPOT.TB assay was performed in 499 participants (243 ATB and 256 LTBI) and another 322 participants (162 ATB and 160 LTBI) who were diagnosed in Qiaokou (training) and Caidian (validation) cohort respectively.
RESULTS
The mean spot sizes (MSS) of early secreted antigenic target 6 (ESAT-6) spot-forming cells (SFC) of T-SPOT.TB assay in ATB patients was significantly higher than that in LTBI individuals. 1.0 × 10 was the optimal number of cells added to phytohaemagglutinin (PHA) well for obtaining more accurate TB-specific antigen to phytohaemagglutinin (TBAg/PHA) ratio. The area under the curve of the diagnostic model by combination of ESAT-6 SFC MSS and modified TBAg/PHA ratio in distinguishing ATB from LTBI was 0.959 in training cohort, with a sensitivity of 90.12% and a specificity of 91.02% when a cutoff value of 0.46 was used. This diagnostic model showed similar performance in the validation cohort. The area under the curve, sensitivity, and specificity were 0.962, 93.21%, and 90.00%, respectively. Further flow cytometry analysis showed that ESAT-6 stimulation induced a significantly higher mean fluorescence intensity of IFN-γ cells in lymphocytes compared with culture filtrate protein 10 (CFP-10) stimulation. In contrast, CFP-10 stimulation induced a significantly higher percentage of IFN-γ cells in lymphocytes compared with ESAT-6 stimulation.
CONCLUSIONS
The combination of the MSS of ESAT-6 SFC and the modified TBAg/PHA ratio of T-SPOT.TB assay showed great value in discriminating ATB from LTBI.
Topics: Antigens, Bacterial; Bacterial Proteins; Humans; Latent Tuberculosis; Mycobacterium tuberculosis; Phytohemagglutinins; Sensitivity and Specificity; Tuberculosis
PubMed: 32360883
DOI: 10.1016/j.jinf.2020.04.038