scholarly journals Reduced endothelial activation upon human blood perfusion of pig kidney xenografts lacking MHC class I and three xenoantigens

2022 ◽  
Author(s):  
Lin Lin ◽  
Franca Witjas ◽  
Konrad Fischer ◽  
Marten Engelse ◽  
Annemarie de Graaf ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Mhc Class I ◽  
Human Blood ◽  
Immune Activation ◽  
Whole Blood ◽  
Blood Perfusion ◽  
Endothelial Activation ◽  
Immune Rejection ◽  
Human Whole Blood ◽  
Activation Response

Abstract Genetically tailored pigs to eliminate human immune rejection of xenografts is one promising solution to the global donor organ shortage. The development of xenograft transplantation has however been hampered by incomplete understanding of its immune rejection and the inability to test this in a human transplantation setting. Here we use an ex vivo organ perfusion system with human whole blood to assess the initial immune activation within the xenograft endothelium at single cell transcriptome level. Renal injury, complement deposition, coagulation and lymphocyte influx are all strongly reduced in genetically modified pig kidneys with porcine MHC class I and three xenoantigens (GGTA1, CMAH, B4GALNT2) eliminated (4KO) compared to wildtype (WT) pig kidneys after 6-hours human blood perfusion. Single cell RNA sequencing of endothelial cells (EC) from 4KO and WT pig kidneys respectively reveal that there is a compartment (cortex, glomeruli and medulla) specific endothelial activation, with cortical and glomeruli endothelial cells being more affected. Differential gene expression analysis shows a downregulation of endothelial transcriptome activation response to human blood perfusion in the 4KO ECs. Pathway enrichment analysis further identify the NF-kB pathway as strongly activated in human blood perfused WT ECs but diminished in the 4KO. In conclusion, the 4KO pig model has strongly reduced endothelial immune activation response when perfused with human whole blood, that goes beyond prevention of humoral rejection. Our data support further development of the 4KO for use in clinical transplantation.

Porcine endothelium induces DNA-histone complex formation in human whole blood: a harmful effect of histone on coagulation and endothelial activation

2016 ◽  
Vol 23 (6) ◽  
pp. 464-471 ◽  
Author(s):  
Hyun Ju Yoo ◽  
Ji-Eun Kim ◽  
Ja Yoon Gu ◽  
Sae Bom Lee ◽  
Hyun Joo Lee ◽  
...  
Keyword(s):  
Complex Formation ◽  
Whole Blood ◽  
Harmful Effect ◽  
Endothelial Activation ◽  
Human Whole Blood

scholarly journals Surface modification of decellularized bovine carotid arteries with human vascular cells significantly reduces their thrombogenicity

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Eriselda Keshi ◽  
Peter Tang ◽  
Marie Weinhart ◽  
Hannah Everwien ◽  
Simon Moosburner ◽  
...  
Keyword(s):  
Surface Modification ◽  
Whole Blood ◽  
Carotid Arteries ◽  
Complete Blood Count ◽  
Ex Vivo ◽  
Vascular Grafts ◽  
Blood Perfusion ◽  
Vascular Cells ◽  
Perfusion System ◽  
Human Whole Blood

Abstract Background Since autologous veins are unavailable when needed in more than 20% of cases in vascular surgery, the production of personalized biological vascular grafts for implantation has become crucial. Surface modification of decellularized xenogeneic grafts with vascular cells to achieve physiological luminal coverage and eventually thromboresistance is an important prerequisite for implantation. However, ex vivo thrombogenicity testing remains a neglected area in the field of tissue engineering of vascular grafts due to a multifold of reasons. Methods After seeding decellularized bovine carotid arteries with human endothelial progenitor cells and umbilical cord-derived mesenchymal stem cells, luminal endothelial cell coverage (LECC) was correlated with glucose and lactate levels on the cell supernatant. Then a closed loop whole blood perfusion system was designed. Recellularized grafts with a LECC > 50% and decellularized vascular grafts were perfused with human whole blood for 2 h. Hemolysis and complete blood count evaluation was performed on an hourly basis, followed by histological and immunohistochemical analysis. Results While whole blood perfusion of decellularized grafts significantly reduced platelet counts, platelet depletion from blood resulting from binding to re-endothelialized grafts was insignificant (p = 0.7284). Moreover, macroscopic evaluation revealed thrombus formation only in the lumen of unseeded grafts and histological characterization revealed lack of CD41 positive platelets in recellularized grafts, thus confirming their thromboresistance. Conclusion In the present study we were able to demonstrate the effect of surface modification of vascular grafts in their thromboresistance in an ex vivo whole blood perfusion system. To our knowledge, this is the first study to expose engineered vascular grafts to human whole blood, recirculating at high flow rates, immediately after seeding.

scholarly journals OBSERVATIONS ON THE PHAGOCYTOSIS OF THE PNEUMOCOCCUS BY HUMAN WHOLE BLOOD

1930 ◽  
Vol 51 (5) ◽  
pp. 675-684 ◽  
Author(s):  
Hugh K. Ward
Keyword(s):  
Human Blood ◽  
Whole Blood ◽  
Type I ◽  
Human Whole Blood ◽  
Type Iii ◽  
Number Of Individuals ◽  
Considerable Range

1. The phagocytic titre of whole human blood against the three types of pneumococcus was determined in a number of individuals. The titre varied over a considerable range in different subjects. 2. Contrary to expectation, the titre in early cases of untreated pneumonia was quite high against the infecting organism, pointing to a local rather than a general lowering of resistance in infection with this organism. 3. Sia's work was confirmed, that the specific carbohydrate has a specific anti-phagocytic action on the blood. This action is more marked in the case of Type III than in Type I.

Metabolism of 75Se-selenite by human whole blood in vitro

1969 ◽  
Vol 47 (8) ◽  
pp. 791-797 ◽  
Author(s):  
Melvin Lee ◽  
Alice Dong ◽  
Joyce Yano
Keyword(s):  
Plasma Protein ◽  
Human Blood ◽  
Release Rate ◽  
Whole Blood ◽  
Human Whole Blood ◽  
First Order ◽  
First Order Kinetics ◽  
Altered Form

When 75Se, as selenite, is added to human blood it is rapidly taken up by the cells (50–70% within 1–2 min) and is then released into the plasma so that most of the radioactivity is in the plasma by 15–20 min. Uptake is inhibited by 10−3 M cyanide. The release of radioactivity from the cells is inhibited by 10−3 M para-chloromercuribenzoate and by 10−3 M iodoacetamide, although these agents do not affect uptake. Azide and 2,4-dinitrophenol (at 10−3 M) do not affect either process. Large quantities of sulfite, sulfate, and selenate (1000 times as much S or Se as 75Se) do not affect uptake or release, but large amounts of selenite (1000 times) inhibit release. The release rate follows first-order kinetics and increases with temperature. 75Se released from cells is bound by a plasma protein but can be removed from the protein by treatment with cysteine. Studies suggest that the released selenium is in an altered form or state, although this product has not been characterized. A hypothetical pathway for the metabolism of selenium is presented to account for the observations.

scholarly journals Factor H-Binding Protein Is Important for Meningococcal Survival in Human Whole Blood and Serum and in the Presence of the Antimicrobial Peptide LL-37

2008 ◽  
Vol 77 (1) ◽  
pp. 292-299 ◽  
Author(s):  
K. L. Seib ◽  
D. Serruto ◽  
F. Oriente ◽  
I. Delany ◽  
J. Adu-Bobie ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Human Blood ◽  
Whole Blood ◽  
Electrostatic Interactions ◽  
Binding Protein ◽  
Alternative Pathway ◽  
Factor H ◽  
Phase Iii ◽  
Human Whole Blood ◽  
Mutant Strains

ABSTRACT Factor H-binding protein (fHBP; GNA1870) is one of the antigens of the recombinant vaccine against serogroup B Neisseria meningitidis, which has been developed using reverse vaccinology and is the basis of a meningococcal B vaccine entering phase III clinical trials. Binding of factor H (fH), an inhibitor of the complement alternative pathway, to fHBP enables N. meningitidis to evade killing by the innate immune system. All fHBP null mutant strains analyzed were sensitive to killing in ex vivo human whole blood and serum models of meningococcal bacteremia with respect to the isogenic wild-type strains. The fHBP mutant strains of MC58 and BZ83 (high fHBP expressors) survived in human blood and serum for less than 60 min (decrease of >2 log10 CFU), while NZ98/254 (intermediate fHBP expressor) and 67/00 (low fHBP expressor) showed decreases of >1 log10 CFU after 60 to 120 min of incubation. In addition, fHBP is important for survival in the presence of the antimicrobial peptide LL-37 (decrease of >3 log10 CFU after 2 h of incubation), most likely due to electrostatic interactions between fHBP and the cationic LL-37 molecule. Hence, the expression of fHBP by N. meningitidis strains is important for survival in human blood and human serum and in the presence of LL-37, even at low levels. The functional significance of fHBP in mediating resistance to the human immune response, in addition to its widespread distribution and its ability to induce bactericidal antibodies, indicates that it is an important component of the serogroup B meningococcal vaccine.

Leukocyte-platelet aggregate adhesion and vascular permeability in intact microvessels: role of activated endothelial cells

2006 ◽  
Vol 291 (2) ◽  
pp. H591-H599 ◽  
Author(s):  
Pingnian He ◽  
Hong Zhang ◽  
Longkun Zhu ◽  
Yanyan Jiang ◽  
Xueping Zhou
Keyword(s):  
Endothelial Cells ◽  
Tissue Injury ◽  
Leukocyte Adhesion ◽  
Single Cells ◽  
Autologous Blood ◽  
Blood Perfusion ◽  
Endothelial Activation ◽  
Confocal Imaging ◽  
Platelet Aggregate ◽  
Microvessel Permeability

Leukocyte-platelet aggregation and aggregate adhesion have been indicated as biomarkers of the severity of tissue injury during inflammation or ischemic reperfusion. The objective of this study is to investigate the mechanisms of the aggregate adhesion and quantitatively evaluate its relationship with microvessel permeability. A combined autologous blood perfusion with single microvessel perfusion technique was employed in rat mesenteric venular microvessels. The aggregate adhesion was induced by systemic application of TNF-α plus local application of platelet-activating factor (PAF). Changes in permeability were determined by measurements of hydraulic conductivity ( Lp) before and after aggregate adhesion in the same individually perfused microvessels. The compositions of the adherent aggregates were identified with fluorescent labeling and confocal imaging. In contrast to leukocyte adhesion as single cells resulting in no increase in microvessel permeability, aggregate adhesion induced prolonged increases in microvessel Lp(6.1 ± 0.9 times the control, n = 9) indicated by the initial Lpmeasurements after 3 h of blood perfusion, which is distinct from the transient Lpincrease caused by PAF-induced endothelial activation in the absence of blood. Isoproteronol (Iso) attenuated aggregate adhesion-mediated Lpincreases if applied after autologous blood perfusion and prevented the aggregate adhesion if the initial endothelial activation is inhibited by applying Iso before PAF administration but showed less effect on single leukocyte adhesion. This study demonstrated that leukocyte-platelet aggregate adhesion via a mechanism different from that of single leukocyte adhesion caused a prolonged increase in microvessel permeability. Our results also indicate that the initial activation of endothelial cells by PAF plays a crucial role in the initiation of leukocyte-platelet aggregate adhesion.

Microcoulometric Determination of Organochlorine Pesticides in Human Blood

1974 ◽  
Vol 57 (3) ◽  
pp. 595-603
Author(s):  
Francis D Griffith ◽  
Robert V Blanke
Keyword(s):  
Sulfuric Acid ◽  
Human Blood ◽  
Retention Time ◽  
Whole Blood ◽  
Industrial Chemicals ◽  
Chlorinated Pesticides ◽  
Human Whole Blood ◽  
Sulfuric Acid Method ◽  
Made In

Abstract Improvements in the microcoulometric halogen system allow analysis of as little as 1 ppb chlorinated pesticides with specificity and linearity. Modifications were made in the sulfuric acid method of extracting pesticides from human whole blood to obtain recovery of 24 pesticides and 7 industrial chemicals. Recovery data were tabulated. Retention time and response tables for OV-210 and SE-30/QF-1 columns were prepared for these compounds, using the microcoulometric detector.

scholarly journals Flow cytometric analysis of cell lineage and immune activation markers using minimal amounts of human whole blood—Field method for remote settings

2021 ◽  
Vol 491 ◽  
pp. 112989
Author(s):  
Sacha Horn ◽  
Mohamed I.M. Ahmed ◽  
Christof Geldmacher ◽  
Thomas F. Marandu ◽  
Jubin Osei-Mensah ◽  
...  
Keyword(s):  
Immune Activation ◽  
Whole Blood ◽  
Flow Cytometric Analysis ◽  
Cell Lineage ◽  
Field Method ◽  
Activation Markers ◽  
Human Whole Blood ◽  
Flow Cytometric

Human whole-blood O2 affinity: effect of CO2

1988 ◽  
Vol 64 (6) ◽  
pp. 2400-2409 ◽  
Author(s):  
G. Kwant ◽  
B. Oeseburg ◽  
A. Zwart ◽  
W. G. Zijlstra
Keyword(s):  
Human Blood ◽  
Whole Blood ◽  
Base Excess ◽  
Recent Literature ◽  
Order Term ◽  
Human Whole Blood ◽  
Healthy Donors ◽  
Bohr Factor ◽  
Influence Of Ph ◽  
Good Agreement

The proton Bohr factor (phi H = alpha log PO2/alpha pH), the carbamate Bohr factor (phi C = alpha log PO2/alpha log PCO2), the total Bohr factor (phi HC = d log PO2/dpH[base excess) and the CO2 buffer factor (d log PCO2/dpH) were determined in the blood of 12 healthy donors over the whole O2 saturation (SO2) range. All three Bohr factors proved to be dependent on SO2, although to a lesser extent than reported in some of the recent literature. At SO2 = 50% and 37 degrees C, we found phi H = -0.428 +/- 0.010 (SE), phi C = 0.054 +/- 0.006, and phi HC = -0.488 +/- 0.007. The values obtained for phi H, phi C, and d log PCO2/dpH were used to calculate phi HC. Calculated and measured values of phi HC proved to be in good agreement. In an additional series of 12 specimens of human blood we determined the influence of PCO2 on phi H and the influence of pH on phi C. At SO2 = 50%, phi H varied from -0.49 +/- 0.009 at PCO2 = 15 Torr to -0.31 +/- 0.010 at PCO2 = 105 Torr and phi C from 0.157 +/- 0.015 at pH = 7.80 to 0.006 +/- 0.009 at pH = 7.00. When on the basis of these data a second-order term is taken into account, a still slightly better agreement between measured and calculated values of phi HC can be attained.

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