WBC Subpopulations Research Articles

NEW NUTRITION TECHNOLOGY IN THE CONDITIONS OF HARMFUL EFFECTS OF ENVIRONMENT.

The authors studied possibility to decrease toxic occupational effects while using dry protein composite mixtures in medical prophylactic nutrition of workers exposed to occuptational hazards. The study was conducted on a machinery building enterpirse of Povolzhsky Federal District, covered a main group of 34 examinees. This group received dry protein composite mixtures (60 g) daily during 21 days as a cocktail in dinner break. The mixture appeared to cause definite positive changes in peripheral blood: normalized ratio of various WBC subpopulations and their absolute quantity, lower and normalized previously diagnosed eosinophilia and lymphocytosis. High biologic value protein, when added to the diet, increases detoxification ability in exposure to occupational hazards. Using protein composite mixture causes positive changes in free radical oxidation in the workers.

Graphene Oxide Nanosheets Modified with Single-Domain Antibodies for Rapid and Efficient Capture of Cells.

Peripheral blood can provide valuable information on an individual's immune status. Cell-based assays typically target leukocytes and their products. Characterization of leukocytes from whole blood requires their separation from the far more numerous red blood cells.1 Current methods to classify leukocytes, such as recovery on antibody-coated beads or fluorescence-activated cell sorting require long sample preparation times and relatively large sample volumes.2 A simple method that enables the characterization of cells from a small peripheral whole blood sample could overcome limitations of current analytical techniques. We describe the development of a simple graphene oxide surface coated with single-domain antibody fragments. This format allows quick and efficient capture of distinct WBC subpopulations from small samples (∼30 μL) of whole blood in a geometry that does not require any specialized equipment such as cell sorters or microfluidic devices.

The influence of vitamin B12 supplementation on the level of white blood cells and lymphocytes phenotype in rats fed a low-protein diet.

Protein malnutrition has a negative effect on body composition and some blood parameters, especially in the young growing organism. One of nutritional factors which could protect against negative consequences of protein deficiency may be B group vitamins. The aim of the study was to investigate the effect of vitamin B12 supplementation on the immune system in rats fed a standard and a low-protein diet. Rats were fed a control (20% of energy from protein) or a protein-deficient diet (4.5% of energy from protein). Half of animals in each group were additionally supplemented with vitamin B12 (300% of the daily intake). The white blood cells analysis and lymphocytes immunophenotyping (number and percentage) were performed. Low-protein diets caused disturbances in WBC and lymphocyte subpopulations in both short- (30-day) as well as long-term periods (90-day). Vitamin B12 supplementation significantly reduced the negative impact of protein malnutrition after 30 days, however had no effect on long-term malnutrition. Furthermore, vitamin B12 addition in rats fed a control diet did not affect the studied parameters. This observation opens the promise of use of vitamin B12 supplementation to improve immune system parameters in protein malnourished organisms.

Immunological and Growth Mediator Response to Cross-Country Training in Adolescent Females

Exercise affects growth and development through a complex interaction between the endocrine, immune, and nervous systems. To date very little is known about how these systems respond to exercise in children or adolescents. Moreover, there are few studies that have examined growth factors, pro-inflammatory cytokines, and peripheral blood mononuclear cell responses to 'real-life' or field exercise solely in girls. To determine the acute exercise-induced alterations in the growth hormone (GH)-insulinlike growth factor-I (IGF-I) axis, inflammatory cytokines, and certain aspects of immune function (white blood cell [WBC] subpopulations and their associated adhesion molecules) in a group of adolescent girls following a typical cross country practice. Eight, healthy, postpubertal, high school females, 15-18 years old, performed a single, typical, one hour cross-country practice session. Blood was sampled before and after the session. Following exercise, lactate increased by 364 +/- 67% (p < 0.001). Significant increases were noted in circulating IL-6 (p < 0.023), TNF-alpha (p < 0.027), IL-1beta (p < 0.047) and IL-1ra (p < 0.002), as well as a substantial increase in GH (p < 0.007). The exercise led to significant increases in all WBC subpopulations and platelets. The most significant changes were observed for natural killer cells (p < 0.0005). The exercise significantly influenced adhesion molecules (such as CD62L, CD54). These data demonstrate that an intense exercise bout in adolescent females leads to profound increases in inflammatory cytokines, with substantial changes in WBC and adhesion molecules. The role of these frequent, almost-daily perturbations on growth, development and immunity has yet to be determined.

Longitudinal monitoring of WBC subsets in packed RBC units after filtration: implications for transfusion transmission of infections

Specific subsets of peripheral blood WBCs are reservoirs for infectious agents, such as CMV and EBV, and can serve as vectors for transfusion transmission of these agents. While filter WBC reduction has been used to prevent transfusion transmission of infections, its effectiveness has not been documented for many infectious agents and in some instances may be difficult to demonstrate in clinical trials. Because the effectiveness of filtration depends on the number of infected WBCs remaining at transfusion, WBC subpopulations in packed RBC units were quantitated after filtration and storage. Packed RBC units (n = 14) were filtered and stored at 4(o)C for 42 days or were stored without filtration. Serial samples were subjected to flow cytometric immunophenotyping of WBC subsets: neutrophils, monocytes, CD4+ and CD8+ T cells, B cells, and NK cells. Filtration produced a mean reduction in total WBCs of 3.2 log. Monocytes, lymphocytes, and neutrophils were reduced by 4.1, 3.8, and 2.5 log, respectively. Lymphocyte subsets also demonstrated differential reduction with filtration. All WBC subsets showed ongoing loss during storage. Monocyte and lymphocyte subsets are removed most effectively by prestorage filtration. Postfiltration storage leads to further significant reductions in WBC subsets. The implications of these findings for the mitigation of transfusion transmission of infection are discussed.

Quantitation of white cell subpopulations by polymerase chain reaction using frozen whole-blood samples. Viral Activation Transfusion Study.

Previous methods for processing whole blood (WB) for nucleic acid analyses of white cells (WBCs) required fresh blood samples. A simple protocol that involves the freezing of WB for quantitative polymerase chain reaction (PCR) analyses was evaluated. Controlled studies were conducted in which paired fresh and frozen WB preparations were analyzed. The integrity of WBCs in the frozen WB samples was first assessed by flow cytometry using CD45 fluorescence, and calibration beads to quantitate recovery of WBC subsets. PCR of an HLA-DQ-A sequence was used to quantitate residual WBCs in a double-filtered red cell (RBC) component spiked with serial dilutions of WBCs, as well as in 51 filtered RBCs and 19 filtered platelet concentrates. Y-chromosome-specific PCR was used to quantitate male WBCs in five female WB samples spiked with serial dilutions of male WBCs and in serially collected frozen WB samples from four females transfused with male blood components. By flow cytometry, all major WBC subpopulations in frozen-thawed WB were quantitatively recovered and immunologically intact, although they were nonviable. HLA-DQ-A PCR quantitation of a dilution series from 8 to 16,700 per mL of WBCs spiked into double-filtered RBCs showed linear correlation of the results with both fresh and frozen preparations of the expected WBC concentrations (r2 = 0.98, p<0.0001 for both), without significant difference between observed and expected values (p>0.05). Y-chromosome-specific PCR results in female WB samples spiked with male WBCs were not significantly different in fresh and frozen preparations over a 3 log10 range of male cells. The results of WBC survival studies on frozen WB samples were consistent with previous observations in fresh blood samples. Direct freezing of WB enables subsequent recovery of WBCs for quantitative PCR analyses, with results comparable to those of fresh preparations.This protocol should facilitate wider implementation of nucleic acid-based analyses for quality control of WBC-reduced components, as well as for prospective clinical studies of microchimerism in transfusion and transplant recipients.

A flow cytometric method for determination of white cell subpopulations in filtered red cells

A flow cytometric method for the detection of low amounts of lymphocytes, monocytes, and granulocytes in filtered red cells (RBCs) was evaluated. In this procedure, the RBCs in the samples were lysed by ammonium chloride treatment and the white cells (WBCs) were detected by flow cytometry according to their specific light-scattering properties. The identity of the WBC subpopulations was confirmed by immunofluorescence with monoclonal antibodies specific for each cell type. Flow cytometric determination of WBCs in filtered RBCs correlated with numbers obtained by both a hemocytometer (r = 0.76) and a radioimmunoassay (r = 0.79). Total numbers of WBCs in RBCs measured by flow cytometry were 59 +/- 13 percent (n = 7) of those measured by electronic particle counting, 32 +/- 6 percent (n = 25) by hemocytometer, and 48 +/- 11 percent (n = 29) by radioimmunoassay. Lymphocytes added to filtered RBCs in a concentration of 1.37 cells per microL were detected at an average of 0.56 +/- 0.22 cells per microL (n = 3). Results with monoclonal antibodies indicated an altered expression of membrane markers on granulocytes after RBC filtration, as seen with cell activation. The inefficiency of the flow cytometric method to detect the total number of WBCs calculated by other methods may reflect filtration-induced changes in light-scattering properties of the WBCs. Although the method described does not accurately quantitate the total numbers of WBCs present in filtered RBCs, it may provide useful information on qualitative aspects of WBC subpopulations.

Methods and theory for analysis of flow of white cell subpopulations through micropore filters.

Methods have been developed for analysing the resistance of WBC to flow, by measuring their transit rates through 5 and 8 microns pore filters at constant pressure. Unfractionated WBC and separated subpopulations have been compared. For either pore size, lymphocytes exhibited least resistance to flow, followed by granulocytes, with monocytes being most resistant. A theoretical model, which represents WBC suspensions as made up of three particle types (a relatively fast and a relatively slow population, plus a pore blocking population) adequately describes the data for flow rate versus volume filtered. For 5 microns pores, this theory indicates that a majority of WBC have transit times approximately less than 0.5 s. Unfractionated and mixed mononuclear samples contained a proportion of particles with transit times an order of magnitude longer, whereas, for granulocytes, no slow flowing population was evident. Removal of monocytes by plating out, reduced the proportion of the slow particles in the mononuclear preparation. Unique values for transit times could not be determined for 8 microns pores, but it could be concluded that the great majority of WBC made a very quick transit, with the flow becoming dominated by a small number of much more resistant cells. Simple flow parameters (initial relative flow rate and slow particle resistance) are described which characterize these two populations. Both 5 and 8 microns pore data indicated that few cells became permanently trapped within pores.

The association of African swine fever virus with blood components of infected pigs.

The distribution of African swine fever virus (ASFV) in whole blood, plasma, red blood cells (RBC) and white blood cell (WbC) sub-populations was determined in pigs infected with virulent virus. Changes in the RBC and WBC populations were also examined. Total WBC counts decreased and RBC numbers remained unchanged during the course of the disease. The number of circulating lymphocytes decreased whilst neutrophil numbers increased owing to the replacement of mature forms by juveniles. Virus was present in all major blood fractions and was associated with equivalent numbers of both RBC and WBC. However, 90 per cent of the virus in whole blood was associated with RBC. Of the WBC subpopulations, virus was definitely associated with lymphocytes and possibly neutrophils.