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Journal of Immunological Methods Jan 2023Inborn errors of immunity (IEI) that present with recurrent infections are largely due to antibody (Ab) deficiencies. Therefore, assessment of the B-cell and Ab...
Inborn errors of immunity (IEI) that present with recurrent infections are largely due to antibody (Ab) deficiencies. Therefore, assessment of the B-cell and Ab compartment is a major part of immunologic evaluation. Here we provide an overview about cellular assays used to study B-cell function and focus on lymphocyte proliferation assay (LPA), opsonophagocytic assay (OPA), and the Enzyme-linked Immunosorbent Spot Assay (ELISPOT) including clinical applications and limitations of these techniques. LPAs assess ex-vivo cell proliferation in response to various stimuli. Clinically available LPAs utilize peripheral blood mononuclear cells and mostly assess T-cell proliferation with pokeweed mitogen considered the most B-cell specific stimulus. In the research setting, isolating B cells or using more B-cell specific stimuli such as CD40L with IL-4/IL-21 or the TLR9 ligand CpG can more specifically capture the proliferative ability of B cells. OPAs are functional in-vitro killing assays used to evaluate the ability of IgG Ab to induce phagocytosis applied when assessing the potency of vaccine candidates or along with avidity assays to evaluate the quality of secreted IgG. The B-cell ELISPOT assesses Ab production at a cellular level and can characterize the Ab response of particular B-cell subtypes. It can be used in patients on IgG therapy by capturing specific Abs produced by individual B cells, which is not affected by exogenous IgG from plasma donors, and when assessing the vaccine response in patients on immunomodulatory drugs that can affect memory B-cell function. Emerging approaches that are only available in research settings are also briefly introduced.
Topics: Humans; Leukocytes, Mononuclear; B-Lymphocytes; Enzyme-Linked Immunospot Assay; Immunoglobulin G; Cell Proliferation
PubMed: 36470409
DOI: 10.1016/j.jim.2022.113395 -
Effects of fatty acid mixtures on proliferation of peripheral blood mononuclear cells in dairy cows.Veterinary Research Communications Jun 2023This in vitro study was performed to assess the effects of three different mixtures of nonesterifed fatty acids (NEFA) on mitogen-driven proliferation of peripheral...
This in vitro study was performed to assess the effects of three different mixtures of nonesterifed fatty acids (NEFA) on mitogen-driven proliferation of peripheral blood mononuclear cells (PBMC) in dairy cows. Substantially, the three mixtures differed for n-6 to n-3 fatty acids (FA) ratio and were intended to mimic plasma NEFA composition of cows given fat supplements with different n-6 to n-3 FA ratio. PBMC from six Holstein heifers were cultured in media containing three different mixtures of oleic, palmitic, stearic, linoleic, palmitoleic, or linolenic acid at concentrations mimicking different degree of lipomobilisation. Proliferation of PBMC was stimulated by concanavalin A or pokeweed mitogen (PWM). Low concentrations of the three mixtures (62.5 and 125 µmol/l), did not affect the ability of PBMC to proliferate. Concentrations of the three mixtures mimicking medium-intense lipomobilisation (500, 1,000 and 1,500 µmol/l) impaired to the same extent proliferation of PBMC. The addition to cultures of the three mixtures at concentration of 250 µmol/l, impaired the proliferation only in PBMC stimulated with PWM. Even in this case, the three mixtures did not exert differential effects on PBMC proliferation. Present results reinforce the hypothesis that high concentrations of plasma NEFA play a role in the immunosuppression taking place in cows undergoing intense lipomobilisation, and authorize to suggest that under these conditions different composition of plasma NEFA in terms of different n-6 to n-3 FA ratio cannot prevent their negative effects on lymphocyte proliferation.
Topics: Cattle; Animals; Female; Fatty Acids; Leukocytes, Mononuclear; Fatty Acids, Nonesterified; Dietary Supplements; Cell Proliferation; Lactation; Diet
PubMed: 36446991
DOI: 10.1007/s11259-022-10024-7 -
European Journal of Nutrition Mar 2023To understand the effects of consuming high-fat and low-fat dairy products on postprandial cardiometabolic risk factors and intestinal immune function, we used an...
PURPOSE
To understand the effects of consuming high-fat and low-fat dairy products on postprandial cardiometabolic risk factors and intestinal immune function, we used an established low birthweight (LBW) swine model of diet-induced insulin resistance.
METHODS
LBW piglets were randomized to consume one of the 3 experimental high fat diets and were fed for a total of 7 weeks: (1) Control high fat (LBW-CHF), (2) CHF diet supplemented with 3 servings of high-fat dairy (LBW-HFDairy) and (3) CHF diet supplemented with 3 servings of low-fat dairy (LBW-LFDairy). As comparison groups, normal birthweight (NBW) piglets were fed a CHF (NBW-CHF) or standard pig grower diet (NBW-Chow). At 11 weeks of age, all piglets underwent an established modified oral glucose and fat tolerance test. At 12 weeks of age, piglets were euthanized and ex vivo cytokine production by cells isolated from mesenteric lymph node (MLN) stimulated with mitogens was assessed.
RESULTS
Dairy consumption did not modulate postprandial plasma lipid, inflammatory markers and glucose concentrations. A lower production of IL-2 and TNF-α after pokeweed mitogen (PWM) stimulation was observed in LBW-CHF vs NBW-Chow (P < 0.05), suggesting impaired MLN T cell function. While feeding high-fat dairy had minimal effects, feeding low-fat dairy significantly improved the production of IL-2 and TNF-α after PWM stimulation (P < 0.05).
CONCLUSIONS
Irrespective of fat content, dairy had a neutral effect on postprandial cardiometabolic risk factors. Low-fat dairy products improved intestinal T cell function to a greater extent than high-fat dairy in this swine model of obesity and insulin resistance.
Topics: Animals; Birth Weight; Diet, Fat-Restricted; Glucose; Immunity; Insulin Resistance; Interleukin-2; Swine; Tumor Necrosis Factor-alpha
PubMed: 36197467
DOI: 10.1007/s00394-022-03013-8 -
Scientific Reports Sep 2022Secondary infections have been shown to complicate the clinical course and worsen the outcome of critically ill patients. Severe Coronavirus Disease 2019 (COVID-19) may...
Secondary infections have been shown to complicate the clinical course and worsen the outcome of critically ill patients. Severe Coronavirus Disease 2019 (COVID-19) may be accompanied by a pronounced cytokine release, and immune competence of these patients towards most pathogenic antigens remains uncompromised early in the disease. Patients with bacterial sepsis also exhibit excessive cytokine release with systemic hyper-inflammation, however, typically followed by an anti-inflammatory phase, causing immune paralysis. In a second hit immune response model, leukocyte activation capacity of severely ill patients with pneumonia caused by SARS-CoV-2 or by bacteria were compared upon ICU admission and at days 4 and 7 of the ICU stay. Blood cell count and release of the pro-inflammatory cytokines IL-2, IFNγ and TNF were assessed after whole-blood incubation with the potent immune stimulus pokeweed mitogen (PWM). For comparison, patients with bacterial sepsis not originating from pneumonia, and healthy volunteers were included. Lymphopenia and granulocytosis were less pronounced in COVID-19 patients compared to bacterial sepsis patients. After PWM stimulation, COVID-19 patients showed a reduced release of IFNγ, while IL-2 levels were found similar and TNF levels were increased compared to healthy controls. Interestingly, concentrations of all three cytokines were significantly higher in samples from COVID-19 patients compared to samples from patients with bacterial infection. This fundamental difference in immune competence during a second hit between COVID-19 and sepsis patients may have implications for the selection of immune suppressive or enhancing therapies in personalized medicine.
Topics: COVID-19; Cytokines; Humans; Immunity; Interleukin-2; Pneumonia, Bacterial; Pokeweed Mitogens; SARS-CoV-2; Sepsis
PubMed: 36109525
DOI: 10.1038/s41598-022-17368-9 -
Veterinary World Jun 2022The reports from the Ministry of Agriculture and Fisheries suggest that camels suffer less compared to goats, sheep, and cows from a number of common infectious diseases...
BACKGROUND AND AIM
The reports from the Ministry of Agriculture and Fisheries suggest that camels suffer less compared to goats, sheep, and cows from a number of common infectious diseases in Oman. However, there is no immunological evidence to substantiate this claim. This present study is, therefore, an attempt to study the immunological responses of camels, goats, sheep, and cows by comparing their oxidative respiratory burst of peripheral blood leukocytes (PBLs) as a marker of innate immunity occurring during phagocytosis and the mitogenic responses of their peripheral blood mononuclear leukocytes (PBMLs) as a marker of their adaptive immune response.
MATERIALS AND METHODS
Ten female adult animals (n = 10) were selected from each species (goats, sheep, and cows). The goats, sheep, and cows were maintained at the Agricultural Experiment Station, while camels were kept at the Royal Camel Corps (RCC). Blood samples were collected from the jugular vein in 7 mL of heparin and ethylenediaminetetraacetic acid vacutainer tubes. The oxidative respiratory burst of PBLs was measured using a chemiluminescence (CL) assay. Reactants consisted of 75 mL of whole blood diluted (1:50), 75 mL of luminol/isoluminol, and 75 mL of zymosan opsonized with non-heat inactivated serum/heat-inactivated serum or non-opsonized zymosan. CL responses were measured as relative light units and expressed as the mean count per minute and peak CL values. The mitogenic response of PBMLs to concanavalin A (Con-A), phytohemagglutinin (PHA), and pokeweed mitogen (PWM) was tested using a WST-8 assay and read spectrophotometrically at 450 nm.
RESULTS
The present findings showed that camel PBLs generate significantly higher CL responses, both intracellularly as well as extracellularly, with zymosan opsonized with autologous serum. Camel PBLs demonstrated a significantly higher (p = 0.001) response when stimulated with zymosan opsonized with heat-inactivated serum compared to those of goat, sheep, and cow lymphocytes from camels exhibited significantly higher (p = 0.001) stimulation indices (SI) with Con-A, PHA, and PWM.
CONCLUSION
The present study suggests that camels are capable of mounting both superior innate as well as adaptive immune responses and provide immunological evidence supporting the belief of some authors, who have proposed that camels are less susceptible to a number of common infectious diseases than other domesticated ruminants.
PubMed: 35993061
DOI: 10.14202/vetworld.2022.1398-1407 -
Veterinarni Medicina May 2022The basic information dealing with the anatomy of the ferret's immune system, cross-reactivity of the ferret leukocytes with polyclonal and monoclonal antibodies ... (Review)
Review
The basic information dealing with the anatomy of the ferret's immune system, cross-reactivity of the ferret leukocytes with polyclonal and monoclonal antibodies and immune response to the mitogens and various infections are presented. The leukocyte numbers in the peripheral blood in the ferrets are lower compared to other species and only one subclass of IgG has been identified in ferrets so far. Lymphocytes make up 12-67% of all the leukocytes in the peripheral blood of the healthy adult ferrets. Lymphocyte subpopulations are similar to other mammals and include T- and B-lymphocytes. T-lymphocytes differentiate into helper (Th) lymphocytes and cytotoxic (Tc) lymphocytes. Currently, ferret granulocytes (CD11), B-lymphocytes (CD79α), T-lymphocytes (CD3), Th-lymphocytes (CD3, CD4), Tc-lymphocytes (CD3, CD8), and CD30, CD45 subpopulations are detected with the use of a number of polyclonal as well as with monoclonal antibodies. In a lymphocyte transformation assay, the mitogen response of the peripheral blood mononuclear cells to concanavalin A (ConA), phytohaemagglutinin (PHA), and pokeweed mitogen (PWM) is the greatest at day 2, 2 and 3, respectively. Serious lymphopenia is observed in ferrets during a distemper infection. A significant decrease in the lymphocyte transformation activity is observed on day 5 and reaches a maximal decrease on days 8-11, with full recovery on days 23-30 after the inoculation of laboratory ferrets with the distemper virus. Ferrets have also been used in studies related to the function of the immune system in infections, Crohn's disease and bronchial asthma.
PubMed: 38716186
DOI: 10.17221/22/2021-VETMED -
Frontiers in Pediatrics 2022Patients with T cell deficiency <10% of normal proliferation are indicated to receive immune reconstruction by hematopoietic stem cell transplantation (HSCT). This study...
BACKGROUND
Patients with T cell deficiency <10% of normal proliferation are indicated to receive immune reconstruction by hematopoietic stem cell transplantation (HSCT). This study aimed to investigate whether non-radioactive assays can be used to quantitatively detect the lymphocyte proliferation <10% of normal as radioactive [H]-thymidine."
METHODS
Radioactive [H]-thymidine, non-radioactive carboxyfluorescein diacetate succinimidyl ester (CFSE), and Ki-67 protein expressions were used to measure the lymphocyte proliferation as calculated using the stimulation index (SI), subtraction percentage, and proliferation index (FlowJo software). Normal references were established for comparison in the absence of parallel healthy controls.
RESULTS
Normal ranges of mitogen-stimulated lymphocyte proliferation were established as a SI of 15-267 (CSFE 47-92%, Ki-67 42-79%) with phytohemagglutinin (PHA) 5 μg/ml stimulation; 19-139 (CFSE 62-83%, 45-74% Ki-67) with concanavalin-A (ConA) 5 μg/ml stimulation; 7-53 (CFSE 6-23%, Ki-67 10-24%) with pokeweed mitogen (PWM) 0.1 ug/ml stimulation; 3-28 (CFSE 4-10%, Ki-67 5-14%) with candida 10 ug/ml stimulation; and 2-27 (CFSE 6-41%, Ki-67 6-30%) with bacille Calmette-Guerin (BCG) 0.02 ng/ml stimulation. The normalized CFSE-proliferation index was between 2.1 and 3.0. Although there was no significant correlation between these three assays in the healthy controls, the SI value for <10% [H]-thymidine proliferation in those with T cell deficiency was compatible with CFSE- and Ki-67-stained lymphocyte percentages, and validated in patients with , and mutations. When calculating [H]-thymidine <10% of normal lymphocyte proliferation, the threshold of parallel controls was more reliable than previously established normal references.
CONCLUSION
The large quantitative value of radioactive [H]-thymidine was more easily recognizable than that for non-radioactive CFSE and Ki-67. Even though the correlation was not significant, those identified to have <10% of normal proliferation by [H]-thymidine could be consistently detected by CFSE and Ki-67, and consequently indicated for HSCT.
PubMed: 35547552
DOI: 10.3389/fped.2022.638549 -
Proteomes Feb 2022We recently identified a deviant bovine immune phenotype characterized by hyperproliferation of lymphocytes after polyclonal stimulation. This phenotype was first...
We recently identified a deviant bovine immune phenotype characterized by hyperproliferation of lymphocytes after polyclonal stimulation. This phenotype was first discovered in dams that responded to PregSure BVD vaccination by producing pathological antibodies, triggering the fatal disease "bovine neonatal pancytopenia" in calves. The aim of the study was to gain deeper insights into molecular processes occurring in lymphocytes of immune phenotypes and the effect on their secretome after immune stimulation. Two discovery proteomic experiments were performed with unstimulated and Pokeweed Mitogen (PWM) stimulated lymphocytes, using label-free LC-MS/MS. In lymphocytes, 2447 proteins were quantified, and 1204 proteins were quantified in the secretome. Quantitative proteome analysis of immune deviant and control samples after PWM stimulation revealed clear differences. The increase in abundance of IL17A, IL17F, IL8, CCL5, LRRC59, and CLIC4 was higher in controls through mitogenic stimulation. In contrast, the abundance of IFNγ, IL2, IL2RA, CD83, and CD200 increased significantly more in immune deviant lymphocytes. Additional pathway enrichment analysis of differentially secreted proteins also yielded fundamental differences between the immune phenotypes. Our study provides a comprehensive dataset, which gives novel insights into proteome changes of lymphocytes from different bovine immune phenotypes. These differences point to the development of diverse immune responses of bovine immune phenotypes after immune stimulation.
PubMed: 35225986
DOI: 10.3390/proteomes10010007 -
Veterinary Immunology and... Jan 2022Ferrets are nowadays frequently used as animal models for biomedical purposes; in many cases, immunosuppression of experimental animals is necessary. The aim of this...
Ferrets are nowadays frequently used as animal models for biomedical purposes; in many cases, immunosuppression of experimental animals is necessary. The aim of this study was to evaluate the effect of intramuscular dexamethasone administration (2 mg/kg as the initiation dose continued with 1 mg/kg q 12 h applied 5 times) on ferret's immune system. In comparison with ferrets which received the saline (n = 5), significantly lower total counts of leukocytes (P < 0.01), lymphocytes (P < 0.01) and monocyte (P < 0.05), as well as absolute numbers of CD4+CD8- (P < 0.01) and CD4-CD8+ (P < 0.01) subsets were noted in dexamethasone treated ferrets (n = 5) the first day after the treatment (D1). Absolute number of CD79+ lymphocytes remained unchanged throughout the experiment. The proliferation activity of lymphocytes in dexamethasone treated ferrets was lower only in D1 using concanavalin A (conA), phytohemagglutinin (PHA) and pokeweed mitogen (PWM); statistical significance was noted using PHA 40 (P < 0.05) and PWM 10 (P < 0.01). Lower neutrophil activity (P < 0.01) was detected in D1 after the dexamethasone treatment in both production of reactive oxygen species (chemiluminescence test) and ingestion of particles (phagocytosis assay). The dexamethasone treatment proved to be useful for short-term immunosuppression in ferrets. The results closely resembled data previously reported in human studies and indicate classification of ferrets as steroid-resistant species.
Topics: Animals; Dexamethasone; Ferrets; Immunosuppression Therapy; Lymphocyte Activation; Models, Animal; Phytohemagglutinins; Pokeweed Mitogens
PubMed: 34826685
DOI: 10.1016/j.vetimm.2021.110362 -
Journal of Neuroimmunology Dec 2021Traumatic brain injury (TBI) is a common cause of morbidity and mortality. We have previously shown that TBI with a concurrent extra-cranial injury reliably leads to...
BACKGROUND
Traumatic brain injury (TBI) is a common cause of morbidity and mortality. We have previously shown that TBI with a concurrent extra-cranial injury reliably leads to post-injury suppression of the innate immune system, but the impact of this injury on the adaptive immune system is unknown. We present data showing that combined injury reduced immune response as assayed in both blood and spleen samples and that these changes parallel apoptosis in the spleen. To assess the clinical relevance of these changes, we examined lungs for spontaneous bacterial colonization.
METHODS
For these studies, prepubescent (28 day old) rats were injured using a controlled cortical impact model and then 25% blood volume removal by arteriotomy, and injured animals were compared with sham injured animals. Blood and spleen samples at post-injury day 1 were incubated with or without immunostimulant and examined for IFN-γ production using an Eli-Spot assay. Spleen samples were also examined for apoptosis using Annexin V staining, and lungs were harvested and plated on blood agar to examine for spontaneous bacterial colonization.
RESULTS
Stimulations of whole blood and spleen samples with phorbol 12-myristate 13-acetate/ionomycin (PMA/I) at post-injury day 1 were associated with significant decreases in IFN-γ-positive cells/million in injured animals. Stimulation of whole blood with either PMA/I or pokeweed mitogen led to reduced tumor necrosis factor alpha production. Spleen from injured animals showed a marked increase in apoptosis. Lung samples showed a 300% increase in colonies per plate in injured animals.
CONCLUSIONS
These data suggest that the combined injury can lead to adaptive immunosuppression, and our findings further suggest a potential role for the spleen in altering leukocyte function following injury.
Topics: Adaptive Immunity; Age Factors; Animals; Apoptosis; Bacterial Load; Brain Injuries, Traumatic; Cerebral Hemorrhage; Disease Models, Animal; Immune Tolerance; Interferon-gamma Release Tests; Leukocytes, Mononuclear; Lung; Male; Multiple Trauma; Pokeweed Mitogens; Rats; Single-Blind Method; Spleen; Tetradecanoylphorbol Acetate; Tumor Necrosis Factor-alpha
PubMed: 34619426
DOI: 10.1016/j.jneuroim.2021.577723