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Comparative Medicine Apr 2020Olive baboons () have provided a useful model of human diseases and conditions, including cardiac, respiratory, and infectious diseases; diabetes; and involving... (Comparative Study)
Comparative Study
Olive baboons () have provided a useful model of human diseases and conditions, including cardiac, respiratory, and infectious diseases; diabetes; and involving genetics, immunology, aging, and xenotransplantation. The development of a immunologically defined SPF baboons has advanced research further, especially for studies involving the immune system and immunosuppression. In this study, we compare normal immunologic changes of PBMC subsets, and their function in age-matched conventional and SPF baboons. Our results revealed that both groups have comparable numbers of different lymphocyte subsets, but phenotypic differences in central and effector memory T-cell subsets are more pronounced in CD4+ T cells. Despite equal proportions of CD3+ T cells among the conventional and SPF baboons, PBMC from the conventional group showed greater proliferative responses to phytohemagglutinin and pokeweed mitogen and higher numbers of IFNγ-producing cells after stimulation with concanavalin A or pokeweed mitogen, whereas plasma levels of the inflammatory cytokine TNFα were significantly higher in SPF baboons. Exposure of PBMC from conventional baboons to various Toll-like (TLR) ligands, including TLR3, TLR4, and TLR8, yielded increased numbers of IFNγ producing cells, whereas PBMC from SPF baboons stimulated with TLR5 or TLR6 ligand had more IFNγ-producing cells. These findings suggest that although lymphocyte subsets share many phenotypic and functional similarities in conventional and SPF baboons, specific differences in the immune function of lymphocytes could differentially influence the quality and quantity of their innate and adaptive immune responses. These differences should be considered in interpreting experimental outcomes, specifically in studies measuring immunologic endpoints.
Topics: Animals; Female; Immunity, Cellular; Male; Monkey Diseases; Papio; Papio anubis; T-Lymphocytes
PubMed: 32014083
DOI: 10.30802/AALAS-CM-19-000035 -
Parasite Immunology Mar 2020Toxoplasma gondii (T gondii) infection has been associated with protection against allergy and autoimmune diseases. We investigated the effects of T gondii infection on...
Toxoplasma gondii (T gondii) infection has been associated with protection against allergy and autoimmune diseases. We investigated the effects of T gondii infection on cytokine and antibody responses in atopic and nonatopic Brazilian subjects. We have measured in whole-blood cultures, Th1 (IFN-γ and IL-12), Th2 (IL-5) and regulatory cytokine IL-10 in blood cells unstimulated and stimulated with pokeweed mitogen or T gondii soluble tachyzoites antigen (STAg) or Dermatophagoides pteronyssinus antigen. A significant negative association was found between high levels of anti-dust mite IgE and T gondii seropositivity (OR = 0.46; 95%CI = 0.25-0.85). STAg stimulation induced a mixed profile of Th1 and Th2 cytokines (IFN-γ, IL-12 and IL-5) in Tg-positive atopic individuals compared with Tg-negative atopic individuals (P < .0001, P = .033 and P = .003, respectively). In contrast, IL-10 production was not different between these groups. No association was found between T gondii infection and asthma. We hypothesized that the protective effect on atopy might be related to the strong Th1 immune response to T gondii found on the seropositive subjects. From our knowledge, this is the first study to investigate the association between atopy and T gondii infection in Brazilian subjects, analysing the cellular immune responses.
Topics: Adult; Animals; Antibodies, Protozoan; Antigens, Protozoan; Asthma; Brazil; Cytokines; Female; Humans; Hypersensitivity; Immunity, Cellular; Immunoglobulin E; Immunoglobulin G; Interleukin-10; Middle Aged; Pyroglyphidae; Toxoplasma; Toxoplasmosis
PubMed: 31884701
DOI: 10.1111/pim.12694 -
Scientific Reports Dec 2019Leukemic cells originate from the malignant transformation of undifferentiated myeloid/lymphoid hematopoietic progenitors normally residing in bone marrow. As the...
Leukemic cells originate from the malignant transformation of undifferentiated myeloid/lymphoid hematopoietic progenitors normally residing in bone marrow. As the precise molecular mechanisms underlying this heterogeneous disease are yet to be disclosed, the identification and the validation of novel actors in leukemia is of extreme importance. Here, we show that KCTD15, a member of the emerging class of KCTD ((K)potassium Channel Tetramerization Domain containing) proteins, is strongly upregulated in patients affected by B-cell type acute lymphoblastic leukemia (B-ALL) and in continuous cell lines (RS4;11, REH, TOM-1, SEM) derived from this form of childhood leukemia. Interestingly, KCTD15 downregulation induces apoptosis and cell death suggesting that it has a role in cellular homeostasis and proliferation. In addition, stimulation of normal lymphocytes with the pokeweed mitogen leads to increased KCTD15 levels in a fashion comparable to those observed in proliferating leukemic cells. In this way, the role of KCTD15 is likely not confined to the B-ALL pathological state and extends to activation and proliferation of normal lymphocytes. Collectively, data here presented indicate that KCTD15 is an important and hitherto unidentified player in childhood lymphoid leukemia, and its study could open a new scenario for the identification of altered and still unknown molecular pathways in leukemia.
Topics: Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Biomarkers, Tumor; Child, Preschool; Female; Gene Expression Regulation, Leukemic; Gene Rearrangement; Histone-Lysine N-Methyltransferase; Humans; Induction Chemotherapy; Male; Myeloid-Lymphoid Leukemia Protein; Potassium Channels; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prognosis
PubMed: 31882877
DOI: 10.1038/s41598-019-56701-7 -
Journal of the American Association For... Nov 2019NHP are a small, but critical, portion of the animals studied in research laboratories. Many NHP are imported or raised at one facility and subsequently moved to another...
NHP are a small, but critical, portion of the animals studied in research laboratories. Many NHP are imported or raised at one facility and subsequently moved to another facility for research purposes. To improve our understanding of the effects of transportation and relocation on the NHP immune system, to minimize potential confounds associated with relocation, and to maximize study validity, we examined the phenotype and function of PBMC in cynomolgus macaques () that were transported approximately 200 miles by road from one facility to another. We evaluated the phenotype of lymphocyte subsets through flow cytometry, mitogen-specific immune responses of PBMC in vitro, and plasma levels of circulating cytokines before transportation, at approximately 24 h after arrival (day 2), and after 30 d of acclimation. Analyses of blood samples revealed that the CD3 and CD4 T-cell counts increased significantly, whereas NK, NKT, and CD14 CD16 nonclassical monocyte subsets were decreased significantly on day 2 after relocation compared with baseline. We also noted significantly increased immune cell function as indicated by mitogen-specific proliferative responses and by IFNγ levels on day 2 compared with baseline. After 30 d of acclimation, peripheral blood CD4 T-cells and monocyte counts were higher than baseline, whereas B-cell numbers were lower. The mitogen-induced responses to LPS and IFNγ production after stimulation with pokeweed mitogen or phytohemagglutinin remained significantly different from baseline. In conclusion, the effects of transportation and relocation on immune parameters in cynomolgus monkeys are significant and do not fully return to baseline values even after 30 d of acclimation.
Topics: Acclimatization; Animal Husbandry; Animals; Cytokines; Laboratory Animal Science; Macaca fascicularis; T-Lymphocyte Subsets; Transportation
PubMed: 31604484
DOI: 10.30802/AALAS-JAALAS-19-000007 -
Journal of Applied Physiology... Dec 2019Critically ill patients are at risk for sepsis, and immunosuppressive mechanisms may prevail. Whether functional tests are helpful to detect immune alterations is...
Critically ill patients are at risk for sepsis, and immunosuppressive mechanisms may prevail. Whether functional tests are helpful to detect immune alterations is largely unknown. Therefore, we tested the hypotheses that reactivity of peripheral blood mononuclear cells (PBMCs) to secrete interferon-γ (IFNγ) following stimulation in vitro is decreased in patients with early sepsis compared with postoperative patients. IFNγ secretion [enzyme-linked immunospot (ELISpot)] in response to stimulation with cytomegalovirus (CMV), pokeweed mitogen (PWM), muromonab-anti-CD3 (OKT3), and human leukocyte antigen (HLA)-DRA-mRNA expression and serum cytokine concentrations were repeatedly [, , , and after intensive care unit (ICU) admission] determined in patients with sepsis ( = 7) and patients undergoing major abdominal surgery (radical prostatectomy, cystectomy, = 10). In a second cohort, expression was assessed in 80 patients with sepsis, 30 postoperative patients, and 44 healthy volunteers (German clinical trials database no. 00007694). In patients with sepsis, IFNγ secretion (ELISpot) was decreased compared with controls after stimulation with CMV ( = 0.01), OKT3 ( = 0.02), and PWM ( = 0.02 on ), whereas unstimulated IFNγ secretion did not differ. expression was also significantly decreased in patients with sepsis at all time points ( = 0.004) compared with postoperative surgical patients, a finding confirmed in the larger cohort. Reactivity of PBMCs to stimulation with CMV, PWM, and OKT3 as well as expression was already decreased upon ICU admission in patients with sepsis when compared with postoperative controls, suggesting early depression of acquired immunity. ELISpot assays may help to clinically characterize the time course of immunocompetence in patients with sepsis. We observed suppression of reactivity to stimulation with cytomegalovirus, muromonab-anti-CD3, and pokeweed mitogen in mononuclear blood cells of patients with early sepsis when compared with postoperative controls. Thus, there is early depression of acquired immunity in sepsis. Enzyme-linked immunospot assays may help to characterize immunocompetence in patients with sepsis.
Topics: Adult; Aged; Cytomegalovirus; Female; Humans; Interferon-gamma; Leukocytes, Mononuclear; Male; Middle Aged; Muromonab-CD3; Pokeweed Mitogens; Sepsis
PubMed: 31545153
DOI: 10.1152/japplphysiol.00438.2019 -
Pediatric Allergy, Immunology, and... Jun 2019Systemic corticosteroids are the standard of care for acute asthma exacerbation. Respiratory infections are known as common triggers of asthma exacerbation, but the...
Systemic corticosteroids are the standard of care for acute asthma exacerbation. Respiratory infections are known as common triggers of asthma exacerbation, but the risk of immune suppression from frequent periodic use of systemic steroids in poorly controlled asthmatic children is not well studied. We conducted a retrospective chart review of 26 children, 3-15 years old with poorly controlled, moderate-to-severe persistent asthma who received ≥2 systemic corticosteroid/year. The data collected include absolute T cell, B cell, and natural killer (NK) cell counts; lymphocyte proliferation studies to phytohemagglutinin (PHA), concanavalin A (CON A), and pokeweed mitogen; immunoglobulin G and M; and antibody titers to tetanus, diphtheria, and pneumococcus. Frequency tables and crosstabs were used to analyze the data. Low CD4 T cell counts were found in 47.8% of the patients, and 45.8% had low CD3 T cell counts. The lymphocyte proliferation studies data exhibited variability, but 21.4%-75% of the subjects who demonstrated normal T cell counts had decreased lymphocyte proliferation studies to PHA and CON A. All the patients had normal immunoglobulins, B cell, and NK cell counts. All but 1 patient had adequate antibody responses to . Frequent systemic corticosteroid use may suppress T cell number and function in asthmatic children. This can potentially lead to increase susceptibility for future infections and asthma exacerbations. Depressed lymphocyte proliferations are observed even in patients who demonstrated normal T cell counts. This emphasizes the importance of adherence to asthma controller medications, and control of asthma triggers, to limit the frequency of steroid use.
PubMed: 31508257
DOI: 10.1089/ped.2018.0988 -
Colloids and Surfaces. B, Biointerfaces Nov 2019Preventing microorganism colonization on a surface is a great challenge in the conception of medical, food and marine devices. Here, we describe the formation of...
Preventing microorganism colonization on a surface is a great challenge in the conception of medical, food and marine devices. Here, we describe the formation of carbohydrate functionalized glass surfaces with D-glucose, D-galactose and D-mannose and how they efficiently affected the bacterial attachment. The carbohydrate entities were covalently attached to the pre-functionalized surface by click chemistry thanks the copper catalysed alkyl-azide cycloaddition. Water contact angle and X-ray photoelectron spectroscopy characterisations showed a homogeneous and quantitative cycloaddition at the scale of microorganisms. The adhesion assays with Pseudomonas aeruginosa, used as model of opportunistic pathogen, indicated a significant diminution of almost 40% of the bacterial accumulation on glycosidic surfaces with respect to initial surface. This activity was further compared with a surface presenting a simple hydroxyl residue. Exploration of specific interactions through Lectin A deficient Pseudomonas aeruginosa mutant strain provided new evidences that Lectin A was involved in biofilm maturation, rather than bacterial attachment. Subsequently, the determination of surface free energy and the adhesion free energy between surfaces and bacterial cell wall showed that the adhesion was thermodynamically unfavourable.
Topics: Azides; Bacterial Adhesion; Biofilms; Click Chemistry; Cycloaddition Reaction; Galactose; Glass; Glucose; Mannose; Pokeweed Mitogens; Pseudomonas aeruginosa; Surface Properties; Thermodynamics
PubMed: 31450058
DOI: 10.1016/j.colsurfb.2019.110383 -
Current Pharmaceutical Biotechnology 2019Interferon-gamma release assays (IGRAs) are blood tests used to measure the amount of interferon-γ (IFN-γ) released by T lymphocytes after stimulation by antigens...
BACKGROUND
Interferon-gamma release assays (IGRAs) are blood tests used to measure the amount of interferon-γ (IFN-γ) released by T lymphocytes after stimulation by antigens specific for the diagnosis of latent tuberculosis infection. A mitogen serves as a positive control to assess the immune function in IGRAs.
METHODS
This in vitro study was conducted to evaluate IFN-γ production by human whole blood stimulated with heat-treated and/or cation-supplemented phytohemagglutinin (PHA), concanavalin A (Con A) and pokeweed mitogen (PWM), using QuantiFERON-TB Gold Kit ELISA tests.
RESULTS
The optimal concentrations of PWM, Con A and PHA for IGRAs were 2 µg/mL, 5 µg/mL and 10 µg/mL, respectively. The results showed that IFN-γ production in response to PWM was the highest and PHA was the lowest amount. The median values of three mitogens were in the following order: PWM≥Con A≥ positive control>>PHA-P>>negative control. PWM and PHA were heat stable, while Con A was heat sensitive. The mitogen response of lymphocytes to untreated or heat-treated PWM and heat-treated Con A was increased in 1 mM Ca2+-supplemented groups, whereas the response to heat-treated PHA was decreased. Exposure to 1 mM Mg2+ had no effect on untreated or heat-treated PWM, and a concentration of 1 mM Zn2+ inhibited the stimulation of un-treated PWM. We found that calcium supplementation improved the PWM-induced production of IFN-γ.
CONCLUSION
Therefore, PWM is an appropriate mitogen for use as a positive control in IGRAs. It is a potential indicator of cytokine production in the diagnostic as well as research settings, and calcium supplementation improved stimulation.
Topics: Adult; Aged; Cations; Concanavalin A; Enzyme-Linked Immunosorbent Assay; Female; Hot Temperature; Humans; Interferon-gamma; Lymphocyte Activation; Male; Middle Aged; Phytohemagglutinins; Pokeweed Mitogens; T-Lymphocytes; Tuberculosis, Pulmonary; Young Adult
PubMed: 31132974
DOI: 10.2174/1389201020666190528093432 -
Fish & Shellfish Immunology Jul 2019Pax5 (Paired Box 5), a nuclear transcription factor expressed in B cell specifically, is a key regulator for B cell activation. In this study, we cloned and identified a...
Pax5 (Paired Box 5), a nuclear transcription factor expressed in B cell specifically, is a key regulator for B cell activation. In this study, we cloned and identified a Pax5 gene (OnPax5) from Nile tilapia (Oreochromis niloticus), which has an open reading frame of 1278 bp, encoding deduced amino acid sequence of 425 residues. OnPax5 contains a conserved DNA-binding domain encoding the paired box, an octapeptide, a homeobox homology region, a transactivation and a repressor domain. OnPax5 is constitutively expressed in various analyzed tissues of tilapia, with a relatively high expression in lymphoid organs, including spleen (SPL), anterior kidney (AK), and thymus. What's more, OnPax5 is highly expressed in leukocytes especially in IgM lymphocytes sorted from peripheral blood (PBL), SPL and AK. When stimulated with lipopolysaccharide (LPS) in vivo, OnPax5 expression was significantly up-regulated in PBL, SPL and AK. Upon stimulation with LPS, pokeweed mitogen and mouse anti-OnIgM monoclonal antibody in vitro, the expression of OnPax5 was also significantly up-regulated in leukocytes from SPL and AK. Taken together, Pax5, the B cell lineage specific activator factor, might get involved in B cell activation in Nile tilapia.
Topics: Amino Acid Sequence; Animals; Base Sequence; Cichlids; Fish Diseases; Fish Proteins; Gene Expression Profiling; Gene Expression Regulation; Immunity, Innate; PAX5 Transcription Factor; Phylogeny; Sequence Alignment
PubMed: 31039440
DOI: 10.1016/j.fsi.2019.04.059 -
Biology of Sex Differences Apr 2019Antarctica challenges human explorers by its extreme environment. The effects of these unique conditions on the human physiology need to be understood to best mitigate...
BACKGROUND
Antarctica challenges human explorers by its extreme environment. The effects of these unique conditions on the human physiology need to be understood to best mitigate health problems in Antarctic expedition crews. Moreover, Antarctica is an adequate Earth-bound analogue for long-term space missions. To date, its effects on human physiology have been studied mainly in male cohorts though more female expeditioners and applicants in astronaut training programs are selected. Therefore, the identification of sex differences in stress and immune reactions are becoming an even more essential aim to provide a more individualized risk management.
METHODS
Ten female and 16 male subjects participated in three 1-year expeditions to the German Antarctic Research Station Neumayer III. Blood, saliva, and urine samples were taken 1-2 months prior to departure, subsequently every month during their expedition, and 3-4 months after return from Antarctica. Analyses included cortisol, catecholamine and endocannabinoid measurements; psychological evaluation; differential blood count; and recall antigen- and mitogen-stimulated cytokine profiles.
RESULTS
Cortisol showed significantly higher concentrations in females than males during winter whereas no enhanced psychological stress was detected in both sexes. Catecholamine excretion was higher in males than females but never showed significant increases compared to baseline. Endocannabinoids and N-acylethanolamides increased significantly in both sexes and stayed consistently elevated during the confinement. Cytokine profiles after in vitro stimulation revealed no sex differences but resulted in significant time-dependent changes. Hemoglobin and hematocrit were significantly higher in males than females, and hemoglobin increased significantly in both sexes compared to baseline. Platelet counts were significantly higher in females than males. Leukocytes and granulocyte concentrations increased during confinement with a dip for both sexes in winter whereas lymphocytes were significantly elevated in both sexes during the confinement.
CONCLUSIONS
The extreme environment of Antarctica seems to trigger some distinct stress and immune responses but-with the exception of cortisol and blood cell counts-without any major relevant sex-specific differences. Stated sex differences were shown to be independent of enhanced psychological stress and seem to be related to the environmental conditions. However, sources and consequences of these sex differences have to be further elucidated.
Topics: Adult; Antarctic Regions; Antigens, Fungal; Catecholamines; Cytokines; Endocannabinoids; Extreme Environments; Female; Hematologic Tests; Humans; Hydrocortisone; Male; Middle Aged; Pokeweed Mitogens; Sex Characteristics; Stress, Psychological; Young Adult
PubMed: 30992051
DOI: 10.1186/s13293-019-0231-0