Rhesus Factor Modulation of Effects of Smoking and Age on Psychomotor Performance,Intelligence, Personality Profile,and Health in Czech Soldiers

Background

Rhesus-positive and rhesus-negative persons differ in the presence-absence of highly immunogenic RhD protein on the erythrocyte membrane. This protein is a component of NH₃ or CO₂ pump whose physiological role is unknown. Several recent studies have shown that RhD positivity protects against effects of latent toxoplasmosis on motor performance and personality. It is not known, however, whether the RhD phenotype modifies exclusively the response of the body to toxoplasmosis or whether it also influences effects of other factors.

Methodology/Principal Findings

In the present cohort study, we searched for the effects of age and smoking on performance, intelligence, personality and self-estimated health and wellness in about 3800 draftees. We found that the positive effect of age on performance and intelligence was stronger in RhD-positive soldiers, while the negative effect of smoking on performance and intelligence was of similar size regardless of the RhD phenotype. The effect of age on four Cattell''s personality factors, i.e., dominance (E), radicalism (Q₁), self-sentiment integration (Q₃), and ergic tension (Q₄), and on Cloninger''s factor reward dependency (RD) was stronger for RhD-negative than RhD-positive subjects, while the effect of smoking on the number of viral and bacterial diseases was about three times stronger for RhD-negative than RhD-positive subjects.

Conclusions

RhD phenotype modulates the influence not only of latent toxoplasmosis, but also of at least two other potentially detrimental factors, age and smoking, on human behavior and physiology. The negative effect of smoking on health (estimated on the basis of the self-rated number of common viral and bacterial diseases in the past year) was much stronger in RhD-negative than RhD-positive subjects. It is critically needed to confirm the differences in health response to smoking between RhD-positive and RhD-negative subjects by objective medical examination in future studies.     

Heterozygote Advantage Probably Maintains Rhesus Factor Blood Group Polymorphism: Ecological Regression Study

Rhesus factor polymorphism has been an evolutionary enigma since its discovery in 1939. Carriers of the rarer allele should be eliminated by selection against Rhesus positive children born to Rhesus negative mothers. Here I used an ecologic regression study to test the hypothesis that Rhesus factor polymorphism is stabilized by heterozygote advantage. The study was performed in 65 countries for which the frequencies of RhD phenotypes and specific disease burden data were available. I performed multiple multivariate covariance analysis with five potential confounding variables: GDP, latitude (distance from the equator), humidity, medical care expenditure per capita and frequencies of smokers. The results showed that the burden associated with many diseases correlated with the frequencies of particular Rhesus genotypes in a country and that the direction of the relation was nearly always the opposite for the frequency of Rhesus negative homozygotes and that of Rhesus positive heterozygotes. On the population level, a Rhesus-negativity-associated burden could be compensated for by the heterozygote advantage, but for Rhesus negative subjects this burden represents a serious problem.     

Mice Expressing RHAG and RHD Human Blood Group Genes

Anti-RhD prophylaxis of haemolytic disease of the fetus and newborn (HDFN) is highly effective, but as the suppressive mechanism remains uncertain, a mouse model would be of interest. Here we have generated transgenic mice expressing human RhAG and RhD erythrocyte membrane proteins in the presence and, for human RhAG, in the absence, of mouse Rhag. Human RhAG associates with mouse Rh but not mouse Rhag on red blood cells. In Rhag knockout mice transgenic for human RHAG, the mouse Rh protein is “rescued” (re-expressed), and co-immunoprecipitates with human RhAG, indicating the presence of hetero-complexes which associate mouse and human proteins. RhD antigen was expressed from a human RHD gene on a BAC or from RHD cDNA under control of β-globin regulatory elements. RhD was never observed alone, strongly indicative that its expression absolutely depends on the presence of transgenic human RhAG. This first expression of RhD in mice is an important step in the creation of a mouse model of RhD allo-immunisation and HDFN, in conjunction with the Rh-Rhag knockout mice we have developed previously.     

The RHD variants in Chinese population

The Rhesus (Rh) blood group system is the most important blood group system in hemolytic disease of the fetus and newborn (HDFN). In clinical transfusions, the D antigen in the Rh blood group system comes third, behind antigens A and B which from ABO blood group system. Over the past decade, molecular technologies have been used to investigate the RHD allele in different ethnic groups. This review first introduces the basic structure of RhD protein and coding genes, then focuses on D-negative, weak D, partial D, DEL, RhD_null variants reported in the Chinese population. To date, more than 460 RHD variants have been reported around the world, but less than 70 RHD variants have been reported in the Chinese population. Further research is needed to identify more RHD polymorphism and establish criteria for blood detection and transfusion guidelines for RHD variants. Only in this way can we better guarantee the safety of blood transfusion and prevent the occurrence of HDFN. With the accumulation of research and clinical data, we should be clearer which RHD variants are to be regarded as RhD negative and which need to be regarded as RhD positive.     

Molecular cloning and primary structure of a Rhesus (Rh)-like protein from the marine sponge Geodia cydonium

 In humans, the 30 000 M _r Rhesus (Rh) polypeptide D (RhD) is a dominant antigen (Ag) of the Rh blood group system. To date, an Rh-like protein has been found in chimpanzees, gorillas, gibbons, and rhesus monkeys. Related to the 30 000 M _r Rh Ag protein are two polypeptides of 50 000 M _r , the human 50 000 M _r Rh Ag and the RhD-like protein from Caenorhabditis elegans. The function of all these proteins is not sufficiently known. Here we characterize a cDNA clone (GCRH) encoding a putative 57 000 M _r polypeptide from the marine sponge Geodia cydonium, which shares sequence similarity both to the RhD Ag and the Rh50 glycoprotein. The sponge Rh-like protein comprises 523 aa residues; hydropathy analysis hints at the presence of ten transmembrane domains. An N-terminal hydrophobic cleavage signal sequence is missing, suggesting that the first membrane-spanning domain of the sponge Rh-like protein acts as a signal-anchor sequence. The sponge Rh-like protein, like the human Rh50, lacks the CLP motif which is characteristic of the 30 000 M _r RhD. In addition, the hydropathy profile of the sponge Rh-like protein is of a similar size and shape as that of human Rh50. This data indicates that the RhD and its structurally related Rh50 glycoprotein, which are highly immunogenic in humans, share a common ancestral molecule with the G. cydonium Rh-like protein. Received: 9 April 1997 / Revised: 29 May 1997     

Immunopurification of the blood group RhD protein from human erythrocyte membranes

Rh proteins are membrane proteins encoded by genes at the blood group RH locus. They are of paramount importance in transfusion medicine, but their function is still unknown. Biochemical and biophysical studies of these proteins are scarce since only minute amounts of the very hydrophobic Rh proteins, can be purified from human erythrocytes. Recently, a human monoclonal antibody (LOR-15C9) was described as having the unique property to recognize the Rh30 protein carrying the major blood group D specificity (RhD protein), either in a membrane detergent extract or when blotted on a membrane. In this report, we describe one-step purification of the RhD protein from detergent extracts of red cell membranes, based on immunoaffinity chromatography carried out with immobilized LOR-15C9 IgG. The technique yielded RhD protein with high purity which was devoid of other associated proteins (RhAG, CD47, LW and GPB) that comprise the Rh complex in the erythrocyte membrane. By contrast immunoprecipitation performed with the same antibody led to co-isolation of both RhD and RhAG.     

Targeted Routine Antenatal Anti-D Prophylaxis in the Prevention of RhD Immunisation - Outcome of a New Antenatal Screening and Prevention Program

Objective

To estimate the incidence of RhD immunisation after implementation of first trimester non-invasive fetal RHD screening to select only RhD negative women carrying RHD positive fetuses for routine antenatal anti-D prophylaxis (RAADP).

Materials and Methods

We present a population-based prospective observational cohort study with historic controls including all maternity care centres and delivery hospitals in the Stockholm region, Sweden. All RhD negative pregnant women were screened for fetal RHD genotype in the first trimester of pregnancy. Anti-D immunoglobulin (250–300 µg) was administered intramuscularly in gestational week 28–30 to participants with RHD positive fetuses. Main outcome measure was the incidence of RhD immunisation developing during or after pregnancy.

Results

During the study period 9380 RhD negative women gave birth in Stockholm. Non-invasive fetal RHD genotyping using cell-free fetal DNA in maternal plasma was performed in 8374 pregnancies of which 5104 (61%) were RHD positive and 3270 (39%) RHD negative. In 4590 pregnancies with an RHD positive test the women received antenatal anti-D prophylaxis. The incidence of RhD immunisation in the study cohort was 0.26 percent (24/9380) (95% CI 0.15–0.36%) compared to 0.46 percent (86/18546) (95% CI 0.37 to 0.56%) in the reference cohort. The risk ratio (RR) for sensitisation was 0.55 (95% CI 0.35 to 0.87) and the risk reduction was statistically significant (p = 0.009). The absolute risk difference was 0.20 percent, corresponding to a number needed to treat (NNT) of 500.

Conclusions

Using first trimester non-invasive antenatal screening for fetal RHD to target routine antenatal anti-D prophylaxis selectively to RhD negative women with RHD positive fetuses significantly reduces the incidence of new RhD immunisation. The risk reduction is comparable to that reported in studies evaluating the outcome of non selective RAADP to all RhD negative women. The cost-effectiveness of this targeted approach remains to be studied.     

Distribution of sialic acid between sialoglycoproteins and other membrane components of different erythrocyte phenotypes.

The sialic acid content of erythrocytes of three different AB0 blood groups have been studied. The sialic acid contents of erythrocyte membranes containing 300 mg protein were determined and compared. Groups 0 (Rhesus negative), AB (both Rhesus negative and positive), and B (Rhesus negative) blood differed significantly (p less than 0.05) in total sialic acid content and in the distribution of sialic acid between sialoglycoproteins and other membrane components. Membrane materials containing 300 mg total protein showed sialic acid contents of 52.73 +/- 2.2 mumol sialic acid for group 0 (Rhesus negative) 34.77 +/- 1.16 mumol for group AB (Rh negative), 32.88 +/- 1.52 mumol for AB (Rh positive) and 21.23 +/- 0.84 mumol for B (Rh negative). In group 0 (Rh. neg.) membranes 39.4 +/- 1.4% of the total sialic acid was associated with the sialoglycoproteins. The percentage of sialic acids associated with sialoglycoproteins in other erythrocyte membranes were 77.7 +/- 1.3% for group B, and 55.6 +/- 1.0% and 56.4 +/- 1.8% for group AB (Rh. negative) and (Rh. positive) respectively. The changes appear to be independent of the Rhesus grouping but dependent on the AB0 grouping since membranes of the two Rhesus types of group AB had identical total sialic acid and sialoglycoproteins sialic acids. The sialic acid densities in sialoglycoproteins also differed from one erythrocyte type to another. Group 0 (Rh. negative) membrane sialoglycoproteins had sialic acid density of 140.5 +/- 3.1 nmol/mg compared to 71.7 +/- 1.2 nmol/mg for group B and 128.1 +/- 2.2 and 124.5 +/- 4.0 nmol/mg for group AB Rhesus negative and Rhesus positive respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of cholesterol on physical properties of human erythrocyte membranes: impact on susceptibility to hydrolysis by secretory phospholipase A2

The ability of secretory phospholipase A₂ (sPLA₂) to hydrolyze cell membranes is highly dependent on the physical properties of the membrane. The effects of cholesterol on these properties have been characterized in artificial bilayers and found to alter sPLA₂ activity significantly. It is hypothesized that the natural difference in cholesterol content between erythrocytes and leukocytes is in part responsible for their differing susceptibility to hydrolysis by sPLA₂. To test this hypothesis, defined amounts of cholesterol were removed from erythrocyte membranes using methyl-β-cyclodextrin. Treatment of cells with methyl-β-cyclodextrin increased the hydrolysis rate and total substrate hydrolyzed by sPLA₂. In general, this effect of cholesterol removal was more pronounced at higher temperatures. Comparison of the level of membrane order (assessed with the fluorescent probe laurdan) with hydrolysis rate revealed that sPLA₂ activity was greatly enhanced upon significant reductions in lipid order. Additional treatment of the cells with calcium ionophore further enhanced the hydrolysis rate and altered the relationship with membrane order. These data demonstrated that interactions with sPLA₂ observed in artificial bilayers apply to biological membranes. It is also proposed that the high level of cholesterol in erythrocyte membranes is a protective mechanism to guard against hydrolytic enzymes.     

Chronic cigarette smoking alters erythrocyte membrane lipid composition and properties in male human volunteers

Cigarette smoking is a major lifestyle factor influencing the health of human beings. The present study investigates smoking induced alterations on the erythrocyte membrane lipid composition, fluidity and the role of nitric oxide. Thirty experimental and control subjects (age 35 ± 8) were selected for the study. Experimental subjects smoke 12 ± 2 cigarettes per day for 7–10 years. In smokers elevated nitrite/nitrate levels in plasma and red cell lysates were observed. Smokers showed increased hemolysis, erythrocyte membrane lipid peroxidation, protein carbonyls, C/P ratio (cholesterol and phospholipid ratio), anisotropic (γ) value with decreased Na⁺/K⁺-ATPase activity and sulfhydryl groups. Alterations in smokers erythrocyte membrane individual phospholipids were also evident from the study. Red cell lysate nitric oxide positively correlated with C/P ratio (r = 0.565) and fluorescent anisotropic (γ) value (r = 0.386) in smokers. Smoking induced generation of reactive oxygen/nitrogen species might have altered erythrocyte membrane physico-chemical properties.     

Raman spectroscopic study of space structure of membrane proteins and membrane lipids in photodamaged human erythrocyte sensitized by hypocrellin B

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The effect of the strongly bound protein fraction on sugar transport in human erythrocyte ghosts

The protein fraction released from human erythrocyte membranes with 90% acetic acid enhanced the transport of several sugar species when enclosed in erythrocyte ghosts. Both the influx and the efflux of d-glucose were increased so that permeation rather than sugar binding was involved. The permeation increase was selective, being found with d-glucose, d-galactose and d-xylose but not with l-glucose or lactose. The protein-dependent sugar transport was saturable and the incorporation of proteins into the ghost membrane brought J_max to the level corresponding to intact erythrocytes, leaving K_m unchanged.     

Erythrocyte lipid composition and sodium transport in human liver disease

In patients with liver disease there are usually increases in erythrocyte cholesterol and phosphatidylcholine concentrations. This increase in membrane lipid changes the shape of the erythrocyte and “spur” or “target” cells may be present. Sodium fluxes were measured in erythrocytes from 17 patients with a variety of liver diseases and from 17 normal subjects and the values related to the lipid content of the membrane. Ouabain-insensitive and ouabain-sensitive effluxes were lower in patients than in normal subjects and the reduction in ouabain-insensitive efflux was more marked. Sodium influx was also significantly lower in erythrocytes from patients than controls. Ouabain-sensitive and ouabain-insensitive effluxes and sodium influx did not correlate with the cholesterol content of erythrocytes from patients. Significant negative correlations were noted between ouabain-insensitive sodium efflux (r = ?0.63, P < 0.01), sodium influx (r = ?0.61, P < 0.01) and intracellular sodium concentration (r = ?0.66, P < 0.01) and the cholesterol : phospholipid molar ratio of the cell but there was no significant correlation between this ratio and the ouabain-sensitive sodium efflux (r = 0.41, P > 0.05). These results support the hypothesis that an altered lipid composition may affect the permeability of the erythrocyte membrane in patients with liver disease.     

Identification of Human Erythrocyte Cytosolic Proteins Associated with Plasma Membrane During Thermal Stress

The influence of thermal stress on the association between human erythrocyte membranes and cytosolic proteins was studied by exposing erythrocyte suspensions and whole blood to different elevated temperatures. Membranes and cytosolic proteins from unheated and heat-stressed erythrocytes were analyzed by electrophoresis, followed by mass spectrometric identification. Four major (carbonic anhydrase I, carbonic anhydrase II, peroxiredoxin VI, flavin reductase) and some minor (heat shock protein 90α, heat shock protein 70, α-enolase, peptidylprolyl cis–trans isomerase A) cytosolic proteins were found to be associated with the erythrocyte membrane in response to in vitro thermal stress. Unlike the above proteins, catalase and peroxiredoxin II were associated with membranes from unheated erythrocytes, and their content increased in the membrane following heat stress. The heat-induced association of cytosolic proteins was restricted to the Triton shells (membrane skeleton/cytoskeleton). Similar results were observed when Triton shells derived from unheated erythrocyte membranes were incubated with an unheated erythrocyte cytosolic fraction at elevated temperatures. This is a first report on the association of cytosolic catalase, α-enolase, peroxiredoxin VI, peroxiredoxin II and peptidylprolyl cis–trans isomerase A to the membrane or membrane skeleton of erythrocytes under heat stress. From these results, it is concluded that specific cytosolic proteins are translocated to the membrane in human erythrocytes exposed to heat stress and they may play a novel role as erythrocyte membrane protectors under stress by stabilizing the membrane skeleton through their interactions with skeletal proteins.     

Relation between various phospholipase actions on human red cell membranes and the interfacial phospholipid pressure in monolayers

The action of purified phospholipases on monomolecular films of various interfacial pressures is compared with the action on erythrocyte membranes. The phospholipases which cannot hydrolyse phospholipids of the intact erythrocyte membrane, phospholipase C from Bacillus cereus, phospholipase A₂ from pig pancreas and Crotalus adamanteus and phospholipase D from cabbage, can hydrolyse phospholipid monolayers at pressure below 31 dynes/cm only.The phospholipases which can hydrolyse phospholipids of the intact erythrocyte membrane, phospholipase C from Clostridium welchii phospholipase A₂ from Naja naja and bee venom and sphingomyelinase from Staphylococcus aureus, can hydrolyse phospholipid monolayers at pressure above 31 dynes/cm. It is concluded that the lipid packing in the outer monolayer of the erythrocyte membrane is comparable with a lateral surface pressure between 31 and 34.8 dynes/cm.     

Structural and quantitative changes of carbohydrate chain of erythrocyte membrane glycoproteins in experimental diabetes mellitus after treatment with agmatine

It was shown that the development of experimental diabetes mellitus accompanied by increase of desialylation of carbohydrate determinants of erythrocytes membrane glycoproteins, removal of both O-linked and N-linked oligosaccharides from the glycoproteins and decrease of erythrocyte membrane negative charges. Treatment of streptozotocin-induced diabetic rats with agmatine led to enhance the content of N-and O-glycans in the erythrocyte glycoproteins, increase in sialic acid content and restore the negative charge of the cell membrane. Detected changes in configuration of membrane components of red blood cells in diabetic animals after treatment with agmatine indicate circulating in the bloodstream cells with a repertoire of adhesion molecules and glycoprotein receptors, which are inherent to the population of young erythrocyte.     

Hypochlorous acid inhibits glutathione S-conjugate export from human erythrocytes

It was found that the hypochlorous acid (HOCl) inhibits the active efflux of glutathione S-conjugates, 2,4-dinitrophenyl-S-glutathione (DNP-SG, c_50%=258±24 μM HOCl) and bimane-S-glutathione (B-SG, c_50%=125±16 μM HOCl) from human erythrocytes, oxidises intracellular reduced glutathione (the ratio [HOCl]/[GSH]_oxidized=4) and inhibits basal as well as 2,4-dinitrophenol- (DNP) and 2,4-dinitrophenyl-S-glutathione (DNP-SG)-stimulated Mg²⁺-ATPase activities of erythrocyte membranes. Multidrug resistance-associated protein (MRP1) mediates the active export of glutathione S-conjugates in mammalian cells, including human erythrocytes. A direct impairment of erythrocyte membrane MRP by hypochlorous acid was shown by electrophoresis and immunoblotting (c_50%=478±36 μM HOCl). The stoichiometry of the MRP/HOCl reaction was 1:1. These results demonstrate that MRP can be one of the cellular targets for the inflammatory mediator hypochlorous acid.     

N Terminus Is Key to the Dominant Negative Suppression of CaV2 Calcium Channels: IMPLICATIONS FOR EPISODIC ATAXIA TYPE 2*

Expression of the calcium channels Ca_V2.1 and Ca_V2.2 is markedly suppressed by co-expression with truncated constructs containing Domain I. This is the basis for the phenomenon of dominant negative suppression observed for many of the episodic ataxia type 2 mutations in Ca_V2.1 that predict truncated channels. The process of dominant negative suppression has been shown previously to stem from interaction between the full-length and truncated channels and to result in downstream consequences of the unfolded protein response and endoplasmic reticulum-associated protein degradation. We have now identified the specific domain that triggers this effect. For both Ca_V2.1 and Ca_V2.2, the minimum construct producing suppression was the cytoplasmic N terminus. Suppression was enhanced by tethering the N terminus to the membrane with a CAAX motif. The 11-amino acid motif (including Arg⁵² and Arg⁵⁴) within the N terminus, which we have previously shown to be required for G protein modulation, is also essential for dominant negative suppression. Suppression is prevented by addition of an N-terminal tag (XFP) to the full-length and truncated constructs. We further show that suppression of Ca_V2.2 currents by the N terminus-CAAX construct is accompanied by a reduction in Ca_V2.2 protein level, and this is also prevented by mutation of Arg⁵² and Arg⁵⁴ to Ala in the truncated construct. Taken together, our evidence indicates that both the extreme N terminus and the Arg⁵², Arg⁵⁴ motif are involved in the processes underlying dominant negative suppression.     

Erythrocyte membrane anion-sensitive Mg2+-ATPase—Identity with monovalent cation sensitive Ca2+-Mg2+-ATPase

• 1.1. Activation of Mg²⁺-ATPase of rabbit and guinea-pig erythrocyte membrane by bicarbonate or chloride could be completely abolished by ethylene-glycol-bis-(β-aminoethylether)-N,N'-tetraacetic acid. The anion stimulation was actually an activation of contaminating Ca²⁺ -stimulated Mg²⁺-ATPase by monovalent cations associated with the anions.
• 2.2. Guinea-pig red cell Ca²⁺-Mg²⁺-ATPase could be activated by both sodium and potassium while the rabbit enzyme was sensitive only to sodium. The concentrations of monovalent cations for half-maximal stimulation of Ca²⁺-Mg²⁺-ATPase are: k_na+ = 40.8 mM, k_k+ = 12.2 mM (guinea-pig); K_Na+ = 13.3mM (rabbit).
• 3.3. Potassium enhanced activation of rabbit erythrocyte membrane Ca²⁺-Mg²⁺-ATPase by red cell Ca²⁺-Mg²⁺-ATPase activator protein. With the guinea pig enzyme, neither sodium nor potassium enhanced activator stimulation of Ca²⁺-Mg²⁺-ATPase.
• 4.4. Ca²⁺-Mg²⁺-ATPase of aged rabbit erythrocyte membrane responded to sodium but not to activator protein.
• 5.5. Triton X-100 solubilized rabbit erythrocyte membrane Ca²⁺-Mg²⁺-ATPase has an apparent molecular weight of 371,000. It did not respond to the activator.
• 6.6. One major and three minor proteins, visualized by SDS-polyacrylamide gel electrophoresis, were extracted from rabbit erythrocyte membrane by 50 μM chlorpromazine.

     

Interaction of Streptococcus mutans YidC1 and YidC2 with Translating and Nontranslating Ribosomes

The YidC/OxaI/Alb3 family of membrane proteins is involved in the biogenesis of integral membrane proteins in bacteria, mitochondria, and chloroplasts. Gram-positive bacteria often contain multiple YidC paralogs that can be subdivided into two major classes, namely, YidC1 and YidC2. The Streptococcus mutans YidC1 and YidC2 proteins possess C-terminal tails that differ in charges (+9 and + 14) and lengths (33 and 61 amino acids). The longer YidC2 C terminus bears a resemblance to the C-terminal ribosome-binding domain of the mitochondrial OxaI protein and, in contrast to the shorter YidC1 C terminus, can mediate the interaction with mitochondrial ribosomes. These observations have led to the suggestion that YidC1 and YidC2 differ in their abilities to interact with ribosomes. However, the interaction with bacterial translating ribosomes has never been addressed. Here we demonstrate that Escherichia coli ribosomes are able to interact with both YidC1 and YidC2. The interaction is stimulated by the presence of a nascent membrane protein substrate and abolished upon deletion of the C-terminal tail, which also abrogates the YidC-dependent membrane insertion of subunit c of the F₁F₀-ATPase into the membrane. It is concluded that both YidC1 and YidC2 interact with ribosomes, suggesting that the modes of membrane insertion by these membrane insertases are similar.