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PubMed1987

Is anticardiolipin activity a cross-reaction of anti-DNA or a separate entity?

Putative cross-reactions between anti-DNA and anticardiolipin activities were studied using sera of different patients and a panel of monoclonal antibodies to DNA. Sera were obtained from patients with systemic lupus erythematosus, from patients with syphilis, and from heroin addicts who showed a biologic false-positive result on the serologic test for syphilis. While the patients with syphilis and the heroin addicts had elevated levels of anticardiolipin antibodies in their circulation, no reactivity with DNA was observed in these sera. Sera from systemic lupus erythematosus patients often showed both anti-DNA and anticardiolipin activity. Although a correlation between anti-DNA and anticardiolipin titers was found, this did not always result from cross-reactivity of the same population of antibodies. In fact, we observed a relationship between cross-reactivity and antibody avidity. Anti-DNA of high avidity to DNA showed little cross-reactivity with cardiolipin. Anticardiolipin activity in such sera was based on the presence of specific anticardiolipin antibodies. Anti-DNA of low avidity was found to cross-react with cardiolipin. Among monoclonal antibodies to DNA, we found that cross-reactions with cardiolipin were rare: only 6 of 55 anti-DNA clones produced antibodies that also reacted with cardiolipin.

Antibody Affinity↗
PubMedDate not supplied

Phospholipids and bile acids as diffusional carriers of Na+ across nonpolar media.

Phospholipids and bile acids, by virtue of their amphiphilic properties, can interact in nonpolar media forming "inverted" structures (micelles) which presumably have an hydrophilic core and might act as diffusional carriers (ionophores) of electrolytes across low dielectric constant media or lipid membranes. The Na+ ionophoretic capability of various purified phospholipids and the modulating effects of bile acids and phosphatidylcholine was examined by: (a) measurement of 22Na+ partition into the organic phase (chloroform) of a two-phase system and (b) direct measurement of the translocation of 22Na+ across a bulk chloroform phase separating two aqueous phases in a Pressman cell. All phospholipids tested, except for phosphatidylcholine, showed ionophoretic capability for Na+ at micromolar concentrations. Cardiolipin and phosphatidylserine were the most efficient Na+ carriers, comparable with monensin, an established Na+ ionophore. In contrast, cholic acid as well as other bile acids demonstrated only marginal or no Na+ ionophoretic capability. However, hydroxylated bile acids (particularly cholic acid), sodium dodecyl sulfate and Triton X-100, which can induce and stabilize inverted structures in lipid membranes, were able to increase 5- to 8-fold the phospholipid-mediated Na+ transport. Interaction of cardiolipin with Na+ in the chloroform phase followed a rectangular hyperbolic function with an apparent Kd within the physiological Na+ concentration range (16.9 +/- 5.1 mM). Addition of cholic acid to the cardiolipin-containing organic phase resulted in a 10-fold increase of maximal Na+ uptake and no change in apparent Kd. The effect of cholic acid on both cardiolipin-mediated Na+ partition and Na+ translocation across the chloroform phase showed a marked dependence on pH, being greater at pH 7.4.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1999

Isolation and characterization of two human monoclonal anti-phospholipid IgG from patients with autoimmune disease.

The antigenic specificity of anti-phospholipid antibodies (APA) is a matter of intensive investigation. To further characterize these antibodies, we attempted to isolate human monoclonal APA. B-cells of patients with at least one positive test for antibodies against cardiolipin, phosphatidylserine, beta2-glycoprotein I (beta2-GPI) or the lupus anti-coagulant were immortalized by transformation with Epstein-Barr virus and screened for production of specific IgG. Positive pools were fused with a heteromyeloma cell line and APA-secreting clones were isolated by standard procedures. Two monoclonal APA, HL-5B from a 51-year-old man with primary anti-phospholipid syndrome and recurrent cerebral microinfarctions, and RR-7F from a 48-year-old women with systemic lupus erythematosus but no evidence for thrombotic events were obtained. HL-5B is of the IgG2 subtype with lambda light chains, while RR-7F is IgG2 with kappa light chains. Both monoclonals show reactivity against cardiolipin and phosphatidylserine but lack reactivity against beta2-GPI or lupus anti-coagulant activity. To yield the same OD in the cardiolipin and phosphatidylserine ELISAs RR-7F must be used in an approximately 10-fold higher concentration than HL-5B, indicating a lower affinity towards these antigens. Interestingly, both mAPA can bind to cardiolipin in the absence of beta2-GPI. They do not cross-react with dsDNA but show reactivity against oxidized low-density lipoproteins. Analysis of the heavy chain mRNA of HL-5B and RR-7F showed that both are members of the VH3 family. While HL-5B shows extensive somatic mutations in the CDR1 and 2 regions, indicating that it was derived by a T cell-dependent antigen driven process, RR-7F is apparently germline encoded. The two monoclonal APA can be used as tools in further structural and functional analyses.

Amino Acid Sequence↗
PubMed2001

Expression of the Fabs of human auto-antibodies in Escherichia coli: optimization and determination of their fine binding characteristics and cross-reactivity.

The Fabs of three human auto-antibodies (B3/33H11, anti-DNA; UK4, anti-phospholipid) and six related hybrids have been cloned and expressed in Escherichia coli, and their relative binding to single-stranded or double-stranded DNA or to cardiolipin has been assessed in the presence of modulators (salts and serum). We describe optimized conditions that have led to significant improvement in the quality and quantity of the purified auto-antibodies. Protein expression of the assembled and functionally active Fabs was achievable with a yield of up to 5 to 9 mg/l of culture. The comparative DNA/cardiolipin-binding analyses of the nine Fabs in the presence of modulators demonstrated that B3 and 33H11 L chains possess both anti-DNA and anti-cardiolipin activities. This is the first report of the demonstration that both anti-DNA and anti-cardiolipin activities may lie on the same light chain of a human auto-antibody. We provide evidence that the auto-antibodies that appeared to be similar, in that they bound DNA or cardiolipin in conventional ELISA immunoassays, exhibited significant difference in their cross-reactivity and binding to the antigen in the presence of modulators. Such auto- antigen specificity and/or cross-reactivity may dictate the potential of an auto-antibody to cause pathogenicity and may provide an explanation as to why apparently similar auto-antibodies behave differently in vivo.

Animals↗
PubMed1994

"Radical theory" of oxidative phosphorylation and photophosphorylation.

Ketyl radicals of acetone, dihydroxy acetone, and cardiolipin ketone react in 1,2-dimethoxyethane with inorganic phosphate (model: diethyl phosphate) to form phosphate esters of isopropanol, glycerol, or cardiolipin, respectively. After administration of diethyl phosphate to phosphate-impoverished rats, cardiolipin diethyl phosphate (probably as enol phosphate) has been isolated from liver mitochondria. Hence it is assumed that the enol phosphates of cardiolipin or of an analogous compound (mitochondria and chloroplasts) can be considered as high-energy intermediates of both oxidative and photochemical phosphorylation. Moreover, owing to earlier investigations which show that the formation of the phosphoric-acid-anhydride bond occurs proton-catalytically by acidolysis of enol phosphates, it is attempted here to combine the classic theories--"Chemical Coupling", "Chemiosmosis", and "Cooperativity", including the "Collision Hypothesis"--into the "Radical Theory of Oxidative Phosphorylation and Photophosphorylation".

Animals↗
PubMed1991

Specific lipids enhance the activity of UDP-GlcNAc: dolichol phosphate GlcNAc-1-phosphate transferase in rat liver endoplasmic reticulum membrane vesicles.

The rate of the reaction catalyzed by UDP-N-acetylglucosamine (GlcNAc):dolichol phosphate GlcNAc-1-phosphate transferase in rat liver endoplasmic reticulum vesicles was shown to be influenced by particular lipids. Utilizing in vitro assay conditions where the membrane vesicles retained latency of glucose-6-phosphatase activity, the addition of phosphatidylethanolamine, cardiolipin, or monogalactosyldiglyceride resulted in severalfold increases in the rate of dolichol pyrophosphate N-acetylglucosamine synthesis. Other phospholipids were not stimulatory. These rates were dependent on the concentrations of the exogenous lipids and of the substrate dolichol phosphate. In the presence of cardiolipin, the membrane-bound enzyme became more susceptible to inactivation by protease K and to inhibition by tunicamycin. Titration of cardiolipin-containing endoplasmic reticulum vesicles with adriamycin indicated that the majority of the cardiolipin was exposed on the outer surface. These results suggest that the particular lipids altered membrane structure in a way that allowed further access of the enzyme to substrate, inhibitor, and other molecules. Lipids observed in these studies to be stimulatory are known to exist in the macromolecular hexagonal phase and may therefore be affecting the GlcNAc-1-phosphate transferase by locally disrupting the bilayer structure of the membrane. As other dolichol-utilizing enzymes have been previously observed by other investigators to be similarly influenced by such lipids, the effects may be common to enzymes of the dolichol cycle.

Animals↗
PubMed1981

Analysis of the hexagonal II phase and its relations to lipidic particles and the lamellar phase. A freeze-fracture study.

Model systems of phosphatidylethanolamine (PE) and cardiolipin (DPG), as pure components and in binary mixtures with phosphatidylcholine (PC) have been morphologically analysed. The relation between the hexagonalII (HII) phase and lipidic particles as well as between the HII phase and the lamellar phase has been studied. Moreover, the periodicity of the various HII tubes was determined. (1) The periodicity of the HII phase of cardiolipin is dependent on the cation involved. DPG-Ca exhibits the smallest tube to tube distance when compared to Mg2+ and Mn2+. Moreover, the DPG-Ca tubes are quite straight, in contrast to the Mg2+ and Mn2+ tubes, which appear to be frequently curved. (2) HII tubes with two distinct diameters have been observed in HII phase containing lipid mixtures. The thickness of the HII tube is related to the composition of the tube. In the cardiolipin-lecithin system, structural separation of the pure cardiolipin HII phase has been suggested with Mg2+ and Mn2+, but not with Ca2+. (3) Models for the HII to lamellar phase transition and for the HII phase to the lipidic particles are presented. (4) Lipidic particles are exclusively found in lipid model systems, which contain HII phase favouring lipids. Morphological evidence is presented which suggests these lipidic particles represent inverted micells. These observations include: (i) there is a strong topological and quantitative relation between HII tubes and lipidic particles, (ii) lipidic particles occur densely packed in conglomerates without the presence of a smooth layer.

Animals↗
PubMed1984

Calorimetric studies of cytochrome oxidase-phospholipid interactions.

Thermotropic phase transitions in phospholipid vesicles reconstituted with mitochondrial cytochrome oxidase (EC 1.9.3.1) were studied using differential scanning calorimetry. Both dimyristoylphosphatidylcholine (DMPC) and mixtures of DMPC and cardiolipin were used at different lipid-to-protein ratios. The incorporated protein reduces the energy absorbed during phase transitions of DMPC vesicles, and causes a small decrease in the transition temperature (tm). delta H depends on the amount of protein in the vesicles. This dependence indicates that about 72 DMPC molecules are influenced per cytochrome alpha alpha 3 monomer. The transition parameters remain unaffected by changes in ionic strength or by reduction of the enzyme. Incorporation of cytochrome oxidase depleted of subunit III into DMPC liposomes resulted in a larger decrease of tm, but the amount of perturbed phospholipids remains similar to that in the case of the intact enzyme. Incorporation of cytochrome oxidase into DMPC/cardiolipin vesicles counteracts the effect of cardiolipin in decreasing the enthalpy of the DMPC transition. Thus cytochrome oxidase segregates the phospholipids by attracting cardiolipin from the bulk lipid. Cytochrome c does not significantly affect this apparent cardiolipin 'shell' around membranous cytochrome oxidase.

Animals↗
PubMed1985

Phospholipid composition and organization of cytochrome c oxidase preparations as determined by 31P-nuclear magnetic resonance.

The molecular organization as well as the composition of the phospholipids in cytochrome c oxidase preparations (bovine heart) were investigated by 31P-nuclear magnetic resonance. In the so-called 'lipid-rich' preparation the lipids were found to form a fluid bilayer around the enzyme since the 31P-NMR spectrum was characteristic of a fast, axially symmetric motion of the phosphate groups with a chemical shift anisotropy of delta sigma = -45 ppm. In contrast, the 'lipid-depleted' cytochrome c oxidase gave rise to a broader spectrum where the motion of the phospholipids was no longer axially symmetric. Nevertheless, the total width of the spectrum was still considerably narrower than observed for immobilized phospholipids in solid crystals. Both enzyme preparations were dissolved in 1% detergent solution and used for high-resolution 31P-NMR spectroscopy. Narrow lines of about 20 Hz linewidth were obtained for both types of enzyme preparations, and well-resolved resonances could be assigned to cardiolipin, phosphatidylethanolamin and phosphatidylcholine. The major differences between lipid-rich and lipid-depleted cytochrome c oxidase were the absolute amount of phospholipid associated with the protein and the relative contribution of the individual lipid classes to the 31P-NMR spectrum. For lipid-rich cytochrome c oxidase about 130 molecules phospholipid were bound per enzyme (approx. 11 cardiolipins, 54 phosphatidylethanolamines and 64 phosphatidylcholines). For lipid-depleted cytochrome c oxidase only 6-18 lipids were bound per enzyme (1 or 2 cardiolipins, 3-8 phosphatidylethanolamines and 2-8 phosphatidylcholines). In contrast to earlier suggestions that cardiolipin is the only remaining lipid in lipid-depleted cytochrome c oxidase, the 31P-NMR studies demonstrate that all three lipids remain associated with the protein.

Animals↗
PubMed1986

Mechanism of inhibition of mitochondrial enzymatic complex I-III by adriamycin derivatives.

We demonstrate here that complex I-III of bovine heart mitochondrial membrane is inhibited by adriamycin derivatives. This inhibition is a cardiolipin-dependent process. This lipid, specific to the inner mitochondrial membrane, has been shown previously to interact specifically with adriamycin in model membranes (Goormaghtigh, E., Chatelain, P., Caspers, J. and Ruysschaert, J.-M. (1980) Biochim. Biophys. Acta 597, 1-14) and in mitochondrial membranes (Cheneval, D., Müller, M., Toni, R., Ruetz, S. and Carafoli, E. (1985) J. Biol. Chem. 260, 13003-13007). The differential scanning calorimetry data indicate that, in multilamellar liposomes, the formation of antibiotic-cardiolipin complexes induces a clustering of cardiolipin molecules. Conformational analysis of the antibiotic-cardiolipin complexes suggests that plane-plane interactions between the antibiotics aromatic moieties stabilize this complex formation. Possible mechanisms of inactivation of complex I-III by adriamycin are proposed.

Animals↗
PubMed1988

A 2H-NMR study on the glycerol backbone of phospholipids extracted from Escherichia coli grown under high osmotic pressure: evidence for multiconformations of phosphatidylethanolamine.

A glycerol-requiring auxotroph was isolated from mutagenized Escherichia coli K-12 UFAts cells. This auxotroph was used for the specific deuteration of E. coli phospholipids. The cells were grown under high osmotic pressure (in the presence of 2.0% KCl). The membrane had a highly saturated fatty acid composition (76% phosphatidylethanolamine, 20% cardiolipin and 4% phosphatidylglycerol). The deuterium magnetic resonance spectra of coarse liposomes of the extracted phospholipids with perdeuterated glycerol incorporated into them were measured. To obtain well characterized information, phospholipid mixtures reconstituted from the deuterated and nondeuterated components at the same ratios as in the case of the total extract were used. On the analysis of the spectra, the following conclusions were drawn. (1) The whole polar region of cardiolipin is dynamically symmetric and quite rigid in the presence of phosphatidylethanolamine. (2) Although the quadrupole splittings of the deuterons at the C-2 and C-3 positions of the glycerol backbone were similar to each other, those at the C-1 position for phosphatidylethanolamine and cardiolipin are different, even in the same bilayer. (3) Furthermore, each C-1 deuteron of phosphatidylethanolamine gave rise to a doublet, suggesting the presence of two backbone conformations, between which there is slow exchange. (4) The polar head group of phosphatidylethanolamine interacts with cardiolipin and phosphatidylglycerol in different ways, which could be responsible for the different osmotic properties of the vesicles composed of them.

Cardiolipins↗
PubMed1980

Alteration in phospholipid composition of Staphylococcus aureus during formation of autoplast.

The phospholipid composition of autoplasts (protoplasts made by autolysis of Staphylococcus aureus 209P was examined. The autoplasts were prepared by incubation of 209P cells in 1.2 M sucrose--0.33 M acetate buffer (pH 5.8). Cardiolipin comprised nearly half the total phospholipid in these autoplasts. Autoplasts had a lower phosphatidylglycerol content than intact cells but similar lysylphosphatidylglycerol content. The increase in cardiolipin content during release of autoplasts was not affected by pH or temperature. The result indicates that removal of the cell wall caused the increase in cardiolipin content. The total amount of phospholipids increased slightly during autoplast formation, but there was no significant increase in fatty acids or diglycerides. The changes of phospholipid composition during formation of the autoplast was due to de novo synthesis of cardiolipin from phosphatidylglycerol.

Bacteriolysis↗
PubMed1985

Phospholipids, sterol carrier protein2 and adrenal steroidogenesis.

Rat adrenocortical cells and preparations of plasma membrane and mitochondria have been employed to assess the effects of phospholipids and of sterol carrier protein2 (SCP2) on specific aspects of adrenal steroidogenesis. With intact cells, liposomal dispersions of cardiolipin caused significant stimulation of corticosterone output, while preparations of phosphatidylcholine, phosphatidylinositol, or the 4'-phosphate and the 4',5'-diphosphate derivatives of phosphatidylinositol were without effect. With the adrenal plasma membrane preparation, none of the added phospholipids affected either sodium fluoride or ACTH-responsive adenylate cyclase activity. With intact mitochondria, only cardiolipin, among the various phospholipids, tested, caused a concentration-dependent stimulation of pregnenolone production. However, even at the highest concentration of cardiolipin tested (500 microM), the stimulatory effect was only half that observed with 0.7 microM SCP2, and the two effectors were not synergistic. SCP2 caused a redistribution of cholesterol from mitochondrial outer to inner membranes, while cardiolipin, which is an activator of cytochrome P-450scc, had no effect on distribution of mitochondrial membrane cholesterol.

Adrenal Cortex↗
PubMed1988

Effects of phospholipids on hydrolysis of trioleoylglycerol by human serum carboxylesterase.

Human serum carboxylesterase (EC 3.1.1.1), purified by affinity chromatography on trimethylammonium anilinium-Sepharose, hydrolyzed the short-chain fatty acid ester tributyrin (40 mumol/mg protein per h), but scarcely hydrolyzed the long-chain fatty acid ester triolein (less than 0.2 mumol/mg protein per h). Phospholipids enhanced triolein hydrolysis by carboxylesterase to various extents, cardiolipin causing the most enhancement (2.5 mumol/mg protein per h). Phosphatidylserine and phosphatidylinositol also enhanced carboxylesterase-catalyzed hydrolysis of triolein (450-980 nmol/mg protein per h). The optimal pH for tributyrin hydrolysis was pH 8.0, but the pH range for triolein hydrolysis was broad, being pH 4.5-7.5. The rates of hydrolyses of monoolein, diolein and triolein by carboxylesterase in the absence and presence of 100 micrograms/ml cardiolipin were 3.9, 0.5 and 0.2 mumol/mg esterase per h and 2.0, 0.6 and 4.0 mumol/mg protein per h, respectively. Thus, on addition of cardiolipin, triolein hydrolysis was enhanced, but tributyrin hydrolysis was reciprocally decreased. Triton X-100 (0.1%) and NaCl (1.0 M) decreased triolein hydrolysis, but did not decrease tributyrin hydrolysis. Mercaptoethanol decreased triolein hydrolysis, but not tributyrin hydrolysis. These results suggest that cardiolipin modifies the interaction of carboxylesterase with substrates in such a way as to facilitate its interaction with a hydrophobic substrate, and that disulfide bonding might be involved in the substrate recognition site.

Carboxylesterase↗
PubMed1995

Thyroxine stimulates phosphatidylglycerolphosphate synthase activity in rat heart mitochondria.

The effect of administration of exogenous thyroxine on mitochondrial phosphatidylglycerol content and biosynthesis was investigated in rat heart ventricles. Rats were treated for 5 consecutive days with thyroxine (250 mg/kg body weight) and on the sixth day after an overnight fast the mass of ventricular mitochondrial phosphatidylglycerol and cardiolipin content were determined. Saline-treated animals served as controls. Thyroxine treatment did not affect body weight but increased heart weight 30% compared with controls. In addition, the ratio of heart weight/body weight (x 1000) was increased from 0.69 in controls to 0.89 in thyroxine-treated rats consistent with this model. Thyroxine-treatment resulted in a 34% increase (P < 0.05) in phosphatidylglycerol and a 23% increase (P < 0.05) in cardiolipin content in ventricular mitochondrial fractions compared with controls. The mechanism for the increase in ventricular mitochondrial phosphatidylglycerol was investigated. Phosphatidic acid:cytidine-5'-triphosphate-1,2-diacylglycerol cytidylyltransferase and phosphatidylglycerolphosphate phosphatase activities were unaltered in the ventricular mitochondria of thyroxine-treated rats. In contrast, phosphatidylglycerolphosphate synthase activity was increased 3.5-fold (P < 0.05) in these mitochondrial fractions compared with controls. As a control for the effectiveness of thyroxine on mitochondria, cardiolipin synthase activity was determined. A 2.8-fold increase (P < 0.05) in cardiolipin synthase activity was observed in ventricular mitochondrial fractions of thyroxine-treated rats compared with controls. We postulate that thyroxine-treatment of rats produces an increase in the pool size of ventricular mitochondrial phosphatidylglycerol and that the mechanism is an increase in phosphatidylglycerolphosphate synthase activity.

Animals↗
PubMed1978

Acid esterase activity in cultured skin fibroblasts and amniotic fluid cells using 4-methylumbelliferyl palmitate.

The properties and levels of acid esterase in cultured skin fibroblasts and amniotic fluid cells were investigated using 4-methylumbelliferyl palmitate as substrate. Determinations of acid esterase activity could be made using as little as 1 microgram cell protein. Cardiolipin increased the activity 2--3 fold at the pH optimum 4.0. The apparent KM for both cell types studied was 196 micrometer without and 96 micrometer with cardiolipin. Acid esterase activity was inhibited by cyanide and thiomersal, but not by iodoacetate and N-ethylmaleimide. However activation by cardiolipin was prevented by iodoacetate, N-ethylmaleimide and also sodium chloride. Skin fibroblasts and primary amniotic fluid cells had similar levels with or without cardiolipin. A cyclic activity was found with subculture but no consistent pattern with passage. The acid esterase deficiency in Wolman's and cholesterol ester storage diseases was demonstrated with this substrate.

Amniotic Fluid↗
PubMed1984

Lipid changes with aging in cardiac mitochondrial membranes.

Mitochondrial membranes were isolated from the myocardium of young (4-month-old) and aged (33-month-old) male Long-Evans rats and compared in terms of cholesterol content and phospholipid and fatty acid composition. In aged rats, as compared to young, the major observations include: markedly higher cholesterol content; increased percentage of sphingomyelin and diphosphatidylglycerol (cardiolipin); in fatty acids, variable changes, with a predominant increase in the 16:0 in most phospholipids except cardiolipin, and sporadic increase in the longer chain (20:0, 24:0) fatty acids in cardiolipin; decreased unsaturation index for most phospholipids but increased for cardiolipin. These results are tentatively interpreted as indicative of an aging-related decrease in fluidity and energy transduction of mitochondrial membrane in the heart of aged rats and may be responsible, in part, for the decrements in cardiac function with aging.

Aging↗
PubMed1990

IgG1 and IgG2 are the predominant subclasses of antiphospholipid antibody in women with the lupus anticoagulant.

We studied the sera of 36 patients with lupus anticoagulant and IgG antibodies against both phosphatidylserine and cardiolipin. Most sera also had IgG antibodies against other phospholipids: 97% against phosphatidylinositol, 91% against phosphatidylglycerol, and 82% against phosphatidylethanolamine. IgG2 was the predominant subclass against cardiolipin and phosphatidylserine; 35 of 36 patients (98%) had IgG2 against both phospholipids. Most patients also had the IgG1 subclass; 32 of 36 (89%) against cardiolipin and 25 of 36 (69%) against phosphatidylserine. IgG3 and IgG4 subclasses were present at very low concentrations and in only a minority of the sera. The antibody response against phosphatidylserine was characterized by significantly less IgG1 than was the response against cardiolipin (P less than 0.01), although the IgG2 responses against each phospholipid were not different. IgG subclasses were unrelated to any other aspect of the patients' history, including a history of thrombocytopenia or thrombosis, a positive antinuclear antibody test, or a diagnosis of systemic lupus erythematosus.

Blood Coagulation Factors↗