Immunization with soluble BDC 2.5 T cell receptor-immunoglobulin chimeric protein:antibody specificity and protection of nonobese diabetic mice against adoptive transfer of diabetes by maternal immunization.

The BDC 2.5 T cell clone is specific for pancreatic beta-cell antigen presented by I-Ag7, and greatly accelerates diabetes when injected into 10-21-d-old nonobese diabetic (NOD) mice. The BDC 2.5 T cell receptor (TCR) has been solubilized as a TCR-IgG1 chimeric protein. All NOD mice immunized against BDC 2.5 TCR-IgG1 produced antibodies recognizing TCR C alpha/C beta epitopes that were inaccessible on the T cell surface. 56% of the mice produced antibodies against the BDC 2.5 clonotype that specifically blocked antigen activation of BDC 2.5 cells. We have used the adoptive transfer model of diabetes to demonstrate that maternal immunization with soluble TCR protects young mice from diabetes induced by the BDC 2.5 T cell clone.

Isotropic concentration profiles during diffusion-limited desorption from anisotropic media.

Imaging of the concentration profiles of the diffusants during molecular adsorption on and desorption from porous media is developing to become an important, very specific tool of monitoring the structure of these media. With the present study we refer to the remarkable phenomenon that even in the case of anisotropic porous media the concentration profiles recorded under desorption may attain isotropic patterns, irrespective of the fact that desorption is limited by anisotropic diffusion. The presentation is based on both dynamic Monte Carlo simulations and analytical considerations.

Expression of tissue inhibitor of metalloproteinases (TIMPs) during early cardiac development.

Matrix metalloproteinases (MMPs) mediate cell migration and tissue remodeling and are important in cardiac development. We examined the expression patterns of two MMP inhibitors, tissue inhibitor of metalloproteinase (TIMP)-2 and TIMP-3, during critical stages of cardiac development. Both TIMP-2 and TIMP-3 mRNA were expressed in the endocardium prior to and during early cushion cell formation. TIMP-2 was continually expressed within the outflow tract (OT) and atrioventricular (AV) cushion cells at all stages examined, whereas TIMP-3 mRNA was undetectable in the AV cushion cells soon after their formation. Subsequently, TIMP-3 mRNA disappeared in cushion cells of the distal OT and this loss progressed toward the ventricle until eventually all of the OT cushion cells lacked detectable TIMP-3 transcripts. TIMP-3, but not TIMP-2, was also expressed within remodeling myocardium. Immunocytochemistry confirmed these findings. These observations suggest that TIMP-2 and TIMP-3 have important but unique roles in early cardiac development.

Affinity and kinetics of the interactions between an alphabeta T-cell receptor and its superantigen and class II-MHC/peptide ligands.

Immune activation is mediated by a specific interaction between the T-cell receptor (TCR) and an antigenic peptide bound to the major histocompatibility complex (MHC). T-cell activation can also be stimulated by superantigens which bind to germline-encoded variable domain sequences of certain TCR beta-chains. We have used a surface plasmon resonance biosensor to characterize the molecular interactions between a class II-restricted alphabeta TCR and its superantigen and MHC/peptide ligands. The extracellular domains of the murine D10 TCR (Valpha2, Vbeta8.2) were expressed in insect cells and secreted as a disulfide-linked heterodimer. In the absence of MHC class II, purified soluble D10 TCR bound to Staphylococcus aureus enterotoxin C2 with an association rate of 1.69+/-0.12 x 10(4)M(-1) sec(-1) and a dissociation rate of 1.9+/-0.47 x 10(-2) sec(-1), giving a dissociation constant of 1.1 microM. Binding of the TCR to S. aureus enterotoxin B was barely detectable and could not be measured accurately due to the rapid dissociation rate. Soluble D10 TCR also bound to a soluble murine MHC class II I-A(k) molecule containing a fused antigenic conalbumin peptide and complementary leucine zipper sequences to facilitate efficient chain pairing. The purified I A(k) chimera specifically stimulated proliferation of the D10 T-cell clone, and bound to immobilized soluble D10 TCR with an association rate of 1.07+/-0.19 x 10(4)M(-1)sec(-1) and a dissociation rate of 2.2+/-0.65 x 10(-2) sec(-1), giving a dissociation constant of 2.1 microM.

Apparent digestibility of neutral detergent fiber in elderly and young adults.

These experiments assessed the ability of the neutral detergent fiber (NDF) method to remove starch and nitrogen from food NDF residues, and nitrogen and endogenous secretions from fecal NDF residues; and compared indices of bowel function, including apparent NDF digestibility, of nine elderly subjects to those of six young women. Subjects consumed similar, controlled "low fiber" diets containing foods typically eaten in the United States. Nitrogen and starch contents of food composite NDF were determined in NDF obtained by the hog alpha amylase modification of the Van Soest procedure, whereas the nitrogen content of fecal NDF was determined using NDF obtained by the unmodified procedure. The modified Van Soest method adequately removed nitrogen and starch from food NDF, but fecal NDF contained nitrogen. Both groups digested the majority of the NDF, 63 and 70% for the elderly and young subjects, respectively. Apparent fiber digestibility, which was measured several times in each subject, increased to 69 and 75% for the two groups, respectively, when a correction was made for the nitrogen in the fecal NDF. Mean gastrointestinal transit time and frequency of defecation of the two age groups were comparable, whereas mean daily wet and dry stool weights of the elderly were larger than those of the young women. These results suggest that the bowel of the elderly may function as well as that of the young adult.

Limits of predicting gastrointestinal transit time from other measures of bowel function.

The two aims of these experiments were first, to examine the relationships between mean daily stool weight, mean weight per stool, frequency of defecation, dye transit time, dietary fiber intake, and transit time of small radiopaque pellets, and second, to determine the ability of these measures of bowel function, singly or in combination, to predict gastrointestinal transit time of the pellets. Variables were observed simultaneously in 13 healthy women consuming controlled low and high cellulose diets. All except one of the correlation coefficients between the measures of bowel function were significant. Stepwise regression analysis retained log stool weight, fiber and dye transit to predict log of the mean transit time of all pellets (R2 = 71.3); the same three variables were selected to predict log of the transit time of 80% of the pellets (R2 = 59.4). Mean daily stool weight explained about 50% of the variation for both measures of transit, while dye transit and dietary fiber explained the rest. Log transformation of either stool weight or pellet transit time or both variables improved the prediction of about 10%. These results suggest that prediction of pellet gastrointestinal transit time from other measures of bowel function may be limited and is influenced significantly by the fiber level of the diet.

Consequences of elevated homocysteine during embryonic development and possible modes of action.

Elevated maternal homocysteine (Hcys) is a well-established risk factor for embryonic toxicity and the development of congenital defects, particularly neural tube closure defects and neurocristopathies. The mechanisms responsible are unclear but early work has focused on the role of folate metabolism because these defects are greatly reduced by folate supplementation. As a consequence, elevated Hcys is often looked upon as being an indirect consequence of faulty folate metabolism, although more recent studies show Hcys may act directly as a teratogen. Because Hcys is at the crossroads of protein and DNA metabolism, has a propensity to chemically modify proteins directly, can generate free radicals, and even perturb ligand binding to certain receptors, the developmental processes Hcys can potentially disturb are enumerable. But in recent years, investigators have begun identifying cellular and molecular targets for the direct action of Hcys. While elevating Hcys can alter a myriad of basic cellular activities needed for normal development, our current understanding as to the specific etiological mechanisms responsible for congenital defects is very speculative. Here we provide an overview of what is currently known regarding the toxicity and teratogenicity of elevated Hcys during embryonic development, paying particular attention to neural tube and neural crest cell morphogenesis.

Safety and efficacy of spinal vs general anaesthesia in bone marrow harvesting.

Bone marrow harvesting (BMH) can be performed with either general (GA) or spinal anaesthesia (SPA). Whether SPA is advantageous in BMH and if this technique is safe for procedures performed in the prone position is still controversial. To evaluate the safety and efficacy of both anaesthetic techniques in BMH, 37 allogeneic donors (nine female, 28 male; 34.3 +/- 9 years; ASA class 1-2) received either spinal (group 1, n =20) or general anaesthesia (group 2, n = 17) according to their personal wishes. Under standardised harvesting conditions, haematology parameters, cell counts (MNC, CD34+), haemodynamic parameters, adverse reactions and patient satisfaction were registered. No differences were seen between groups with respect to demographic data, harvesting time (55 +/- 17 vs 60 +/- 16 min) and bone marrow cell counts (MNC: 6.68 +/- 2.1 vs 5.7 +/- 1.7 ml/10(6)). The incidence of hypotension was higher in group 1 (45 vs 10.8%; P =0.042). Postoperative analgesic requirement and emesis were increased in group 2 (P < 0.04) in comparison to group 1. In conclusion, the present study failed to show superiority of spinal over general anaesthesia with regard to the quality of the harvested bone marrow. However, the lower incidence of complaints after spinal anaesthesia appears to offer an advantage over GA in healthy allogeneic bone marrow donors.

Significance and quantitative analysis of von Willebrand factor in human platelets.

The von Willebrand factor (vWF) is found in plasma and in platelets. The concentration and multimeric composition of the vWF in platelets of 160 patients with bleeding tendency were examined since very little is known about the platelet vWF. For quantitative analysis of the platelet vWF, a modified ELISA was established. A reference range from 70%-130% of platelet vWF concentration considered normal was established by examining 80 healthy blood donors. 16.9% of the 160 patients showed a decreased vWF concentration in platelets only, while all the other coagulation parameters were normal. 3 of our patients belong to the same family and suggesting an autosomal dominant genetic transmission for the von Willebrand disease type 1-3. The data also suggests, that a quantitative and qualitative analysis of the vWF in plasma and platelets is required for an exact diagnosis of the von Willebrand disease.

Diet of women with Crohn's and other gastrointestinal diseases.

Our results do not support the assertion that subjects with Crohn's disease consume significantly more sugar than controls or those with ulcerative colitis. A subgroup of patients may consume a high proportion of total kilocalories as sugar. In spite of recommendations to increase their dietary fiber intake, subjects with irritable bowel syndrome did not receive significantly more fiber from food sources. Clearly more research is needed to characterize the sugar and dietary fiber intakes of patients with gastrointestinal diseases.

Transcranial Doppler sonography mean flow velocity during infusion of ultrapurified bovine hemoglobin.

A number of studies have shown that polymerized bovine hemoglobin (HBOC-201) does not cause clinically significant side effects. This has been demonstrated in spite of the fact that a primary increase in oxygen extraction ratio has been associated with an increase in systemic vascular resistance (SVR) and a decrease in cardiac index (CI). The current study investigated the effects of HBOC-201 on cerebral circulation. Middle cerebral artery mean flow velocity (Vm) was measured using Transcranial Doppler sonography. After institutional review board approval and informed consent were obtained, 12 patients (mean age 59+/-10 years), scheduled for hepatic resection, were enrolled. Anesthesia during the induction period consisted of etomidate (0.3 mg/kg), fentanyl (3 mcg/kg), and vecuronium (0.1 mg/kg). Anesthesia during the maintenance period consisted of isoflurane (0.64-0.8 vol%)/O2/N2O (FiO2=0.3), fentanyl, and vecuronium. End-tidal carbon dioxide partial pressure (PetCO2), arterial carbon dioxide partial pressure (PaCO2), mean arterial blood pressure (MAP), CI, SVR, mean flow velocity, and pulsatility index were measured in each patient. Hemodilution was performed in all patients, followed by randomized assignment to two groups: Group 1 (n=6) received 0.4 g/kg HBOC-201, Group 2 (n=6) received a corresponding volume of hydroxyethyl starch (mw 70,000). Measurements were taken at six points (PMs): before hemodilution (PM 1); following hemodilution (PM2); and at 3, 10, 20, and 30 minutes (PM 3-6) after infusion of HBOC-201 or starch. Systemic vascular resistance rose in Group 1 as compared with Group 2, with significant differences at PM 3-6. The greatest difference was at PM 6 (Group 2=1071 dyne x s x cm(-5); Group 1=2154 dyne x s x cm(-5)). Cardiac indices were significantly lower in Group 1 (1.7-1.8 l/minute x m(-2)) than in Group 2 (2.4-2.7 l/minute x m(-2)) after PM 3. After hemodilution, mean flow velocity showed an insignificant increase in both groups, ranging from 39 to 46 cm/second. Although SVR increased significantly following HBOC-201 -infusion, the results of this study did not reveal changes in cerebral blood flow that establish significant group-to-group differences.

Correlation of transcranial Doppler sonography mean flow velocity with cerebral blood flow in patients with intracranial pathology.

Several studies suggest that relative changes in cerebral blood flow (CBF) may be assessed via transcranial Doppler sonography (TCD). The present study investigates the correlation between changes in TCD-mean flow velocity (Vm) and changes in CBF in patients with a variety of types of intracranial pathology undergoing cerebrovascular reactivity tests. After informed consent was obtained, 32 patients presenting with stenoses of brain-supplying arteries (n = 13), cerebral vascular malformations (n = 6), surgical decompression for subarachnoid hemorrhage (n = 2), brain edema after closed head injury (n = 8), or hepatic encephalopathy (n = 3) were studied. The patients were divided into two groups for different reactivity tests. Patients in group 1 (awake or sedated, n = 18) received a 1-g dose of acetazolamide intravenously. In group 2 (n = 14), mechanical ventilation was adjusted to produce a 20% decrease in arterial CO2 tension compared with baseline. Regional CBF was measured using xenon-enhanced computed tomography (Xe-CT). Xe-CT scans at the levels of the basal ganglia and the lateral ventricles were performed during a 4.5-min xenon wash-in period. Bilateral flow velocity was measured in the middle cerebral artery using a 2-MHz pulsed TCD system. Mean arterial blood pressure, heart rate, and end-tidal CO2 were continuously recorded during the procedure. After baseline measurements and either alteration of CO2 or application of acetazolamide, the cerebrovascular reactivity was assessed at 20 min by a second measurement of CBF, TCD, and all other physiologic variables. The correlation coefficient for relative changes of MCA territory CBF versus Vm and for the overall population was r = 0.82. In groups 1 and 2, the r values were 0.39 and 0.5, respectively. Correlation coefficients did not exceed r = 0.4 in any subgroup-classification based on diagnosis. The close correlation between changes in CBF and Vm (r = 0.82) in patients with heterogeneous intracranial pathology seems to show that TCD is a measure of CBF. However, in groups 1 and 2 and in subgroups formed of patients classified according to diagnoses, data dispersion suggests that the actual correlation is weaker. Relation of changes in Vm to those in CBF may depend on the underlying diagnosis. These data indicate that the correlation between Vm and CBF may vary with intracranial pathology.

Molecular traffic control in single-file networks with fast catalysts.

As a model for molecular traffic control we investigate the diffusion of hard core particles in crossed single-file systems. We consider a square lattice of single-files being connected to external reservoirs. The (vertical) alpha channels, carrying only A particles, are connected to reservoirs with constant density rho(A). B particles move along the (horizontal) beta channels, which are connected to reservoirs of density rho(B). We allow the irreversible transition A-->B at intersections. We are interested in the stationary density profile in the alpha and beta channels, which is the distribution of the occupation probabilities over the lattice. We calculate the stationary currents of the system and show that for sufficiently long channels the currents (as a function of the reservoir densities) show in the limit of large transition rates nonanalytic behavior. The results obtained by direct solution of the master equation are verified by kinetic Monte Carlo simulations.

Prediction of multicomponent liquid adsorption using excess quantities. III. Calculations for the liquid/air interface.

The utilization of excess quantities as the basis of a thermodynamic approach can simplify the prediction of multicomponent data from binary ones. Whereas in Part II the excess formalism was applied to the prediction of liquid phase adsorption on solids, in this paper, the liquid/air interface is investigated. In order to show the generality of the suggested approach, thermodynamic equations are developed in analogy to Part II. Surface tensions are predicted by different excess models and compared with experimental data. From predicted surface tensions, ternary adsorption isotherms on the liquid/air interface are calculated.

Legume promotion in counselling: an e-mail survey of dietitians.

Little is known about dietitians current practice in counselling clients about the use of legumes in a low fat, high fibre diet. An exploratory e-mail questionnaire was sent to members of Dietitians of Canada to assess: dietitian use and preferences for legumes, dietitian practice, opinions about clients attitudes and preferences, and resource needs. Counsellors (n=256) had high personal use of legumes (64% > or = 1 serving/week) and frequently recommended legumes in counselling. The legumes most preferred by respondents and their clients were: peanuts, kidney beans, split peas, chickpeas, and lentils. Respondents often recommended canned bean products (76%) and tofu (61%), but other legume grocery products were less often recommended. The most common client issues identified were: flatulence (87% agreed), lack of familiarity (85%), and knowledge of preparation (82%). Dietitians were not satisfied with current resources to support practice, especially those respondents providing primarily clinical counselling services. The most requested resources were: recipes (90%), pamphlets (82%), food demonstrations (75%) and Internet sites (63%). Client level research is now needed to confirm the importance of the issues identified and to develop and test strategies for legume promotion in counselling.

Self-reported health behaviour change in adults: analysis of the Canadian Community Health Survey 4.1.

INTRODUCTION: Knowledge of Canadians' experiences in making health behaviour changes (HBCs) in general, and among those at risk due to body mass index (BMI), would help inform health promotion / disease prevention programs. Selected self reported HBCs in the past 12 months by BMI category were examined in this secondary analysis of the Canadian Community Health Survey 4.1. These HBCs included increased sports/exercise, weight loss and improved eating habits. Barriers to HBC were also examined. METHODS: Descriptive analyses and forward stepwise logistic regression were completed on data from respondents 18 years and older. Self-reported BMI was corrected by the method of Connor Gorber et al. (2008). RESULTS: Our final sample was n = 111 449. Overall, 58% of respondents had made an HBC, with increased sports/exercise as the most important HBC in 29% of the sample, followed by improved eating habits (10%) and weight loss (7%). Half (51%) experienced barriers to HBC; lack of will power was most commonly cited, followed by work and family responsibilities. Obese respondents reported HBC more frequently than normal-weight respondents (60% vs. 55%), but the prevalence of increased sports/ exercise and improved eating habits was similar across BMI categories. Regression models accounted for only 6%-10% of the total variance. CONCLUSION: That a majority of respondents had made at least one HBC bodes well for positively shifting population health. Additional work to further characterize the population, and to improve on population indicators, is needed to assess the impact of health promotion/disease prevention efforts. These findings provide important first population benchmarks for future work.

TITRE: Changements de comportement en matière de santé autodéclarés chez les adultes : une analyse de l'Enquête sur la santé dans les collectivités canadiennes, cycle 4.1. INTRODUCTION: Connaître l'expérience des Canadiens ayant trait aux changements de comportement en matière de santé (CCS), que ce soit en général ou celle des personnes à risque en raison de leur indice de masse corporelle (IMC), serait utile à l'élaboration de programmes de promotion de la santé et de prévention des maladies. Nous avons ainsi examiné, dans le cadre d'une analyse secondaire du cycle 4.1 de l'Enquête sur la santé dans les collectivités canadiennes, une sélection de CCS autodéclarés au cours des douze derniers mois, par catégorie d'IMC : faire plus d'exercice ou de sport, perdre du poids et améliorer ses habitudes alimentaires. Nous nous sommes aussi penchés sur les obstacles aux CCS. MÉTHODOLOGIE: Nous avons analysé les données provenant des répondants de 18 ans et plus à l'aide d'une méthode de régression logistique progressive ascendante. Les IMC autodéclarés ont été corrigés à l'aide de la méthode de Connor Gorber et ses collaborateurs (2008). RÉSULTATS: Notre échantillon final était de 111 449 répondants. Sur l'ensemble des répondants, 58 % avait fait un CCS, l'augmentation de la pratique sportive ou d'exercice étant le plus important (29 % des répondants), suivi par l'amélioration des habitudes alimentaires (10 %) et la perte de poids (7 %). La moitié (51 %) des répondants avaient rencontré des obstacles, le manque de volonté étant l'obstacle le plus souvent mentionné, suivi par l'emploi du temps professionnel et les responsabilités familiales. Les répondants obèses ont fait état de CCS plus souvent que les répondants dont le poids était normal (60 % contre 55 %), mais la fréquence de l'augmentation de la pratique sportive ou d'exercice et de l'amélioration des habitudes alimentaires était similaire selon toutes les catégories d'IMC. Les modèles de régression ne représentaient que de 6 % à 10 % de la variance totale. CONCLUSION: Le fait que la majorité des répondants ait tenté d'apporter au moins un CCS est de bon augure pour une évolution positive de la santé de la population. D'autres travaux sont nécessaires pour mieux caractériser la population et pour améliorer les indicateurs qui lui sont associés, et ainsi évaluer l'incidence des efforts de promotion de la santé et de prévention des maladies. Nos résultats fournissent des données de référence pouvant servir de base à ces travaux.

Further advancements in predicting adsorption equilibria using excess formalism: calculation of adsorption excesses at the liquid/solid interface.

Prediction of adsorption equilibria for ternary liquid mixtures on solid surfaces by means of adsorption data for the corresponding three binary liquid mixtures can be improved by combining the thermodynamic excess formalism with geometrical models. This new strategy for the prediction of excess adsorption isotherms is examined for four ternary adsorption systems ranging from ideal to highly non-ideal ternary mixtures. The predicted isotherms are discussed and compared with experimental ones as well as with those obtained for a model based on the absolute quantities. The results confirm: (i) superiority of predicting adsorption in terms of excess quantities, and (ii) utility of geometrical models for constructing ternary molar compositions on the basis of binary ones to predict equilibria not only for liquid mixtures alone but also for adsorption of liquid mixtures on solid surfaces.

Microarray analysis of homocysteine-responsive genes in cardiac neural crest cells in vitro.

The amino acid homocysteine increases in the serum when there is insufficient folic acid or vitamin B(12), or with certain mutations in enzymes important in methionine metabolism. Elevated homocysteine is related to increased risk for cardiovascular and other diseases in adults and elevated maternal homocysteine increases the risk for certain congenital defects, especially those that result from abnormal development of the neural crest and neural tube. Experiments with the avian embryo model have shown that elevated homocysteine perturbs neural crest/neural tube migration in vitro and in vivo. Whereas there have been numerous studies of homocysteine-induced changes in gene expression in adult cells, there is no previous report of a homocysteine-responsive transcriptome in the embryonic neural crest. We treated neural crest cells in vitro with exogenous homocysteine in a protocol that induces significant changes in neural crest cell migration. We used microarray analysis and expression profiling to identify 65 transcripts of genes of known function that were altered by homocysteine. The largest set of effected genes (19) included those with a role in cell migration and adhesion. Other major groups were genes involved in metabolism (13); DNA/RNA interaction (11); cell proliferation/apoptosis (10); and transporter/receptor (6). Although the genes identified in this experiment were consistent with prior observations of the effect of homocysteine upon neural crest cell function, none had been identified previously as response to homocysteine in adult cells.

[Effect of various plasma preparations and i.v. immunoglobulins on the function of lymphocytes and monocytes in vitro]. / Wirkung verschiedener Plasmapräparationen und i.v.-Immunoglobuline auf die Funktion von Lymphozyten und Monozyten in vitro.

Transfusion of whole blood or blood components has an immunosuppressive effect on the recipient and induces changes of several immunological parameters. Especially blood plasma or plasma components were suspected to show an immunosuppressive action. We therefore studied in vitro the effects of autologous and homologous fresh frozen plasma (FFP), fresh plasma (FP) and heparin plasma (HP) as well as the influence of different commercial i.v. immunoglobulins (IVIG) on the mixed lymphocyte reaction (MLR), the mitogen-induced lymphocyte transformation and the inhibition of phagocytosis of red blood cells, measured in the monocyte-monolayer assay (MMA). We demonstrate that autologous and homologous plasma inhibit the PHA and ConA response of lymphocytes (p < 0.025). Minimal differences between homo- and autologous plasma were only observed for FP in PHA-induced lymphocytes. IVIG reduced, in a dose-dependent manner, the MLR and PHA response to basal values. In contrast, plasma and IVIG showed only small effects on the PWM response rates. The addition of FFP, FP, HP or IVIG to cultured monocytes resulted in a significant inhibition of red blood cell phagocytosis, ranging from 76 to 87%. We conclude from our study that, besides unspecific mechanisms, an unknown plasma factor which is enriched in the immunoglobulin fraction of plasma is able to suppress the T-cell immune response.

[New diagnostic developments in infection serology]. / Neue diagnostische Entwicklungen in der Infektionsserologie.

New developments concerning the diagnostic of virus-transmitted diseases led to a strong improvement of virus security in hemotherapy. The introduction of additional virus antigens associated with the core region of the hepatitis C virus (HCV) resulted in an increase of sensitivity and especially of specificity of second-generation enzyme immuno assays (EIAs). The recombinant immunoblot (RIBA) with 4 synthetic antigens continues to be the most accepted confirmatory test in the field of HCV diagnostic. Beside the simultaneous detection of specific IgG and IgM, especially the HIV-p24 antigen test is discussed concerning HIV-1, -2 diagnostic in order to shorten the 'windows period' in the early time of infection. It is assumed that the HIV-p24 antigen test is not able to effectively improve virus security in areas with low HIV-1, -2 prevalence.