HLA in Georgians (Caucasus) and their relationship with Eastern Mediterraneans.

HLA-A, -B, -DQB1, and -DRB1 typing has been performed in a sample of Georgian population (South Caucasus). Allele frequencies, neighbour joining and correspondence relatedness analyses and extended HLA haplotypes have been obtained with comparison with other Middle East and Mediterranean populations. Our Georgian sample tends to be genetically related in these analyses with Eastern Mediterraneans and Middle East people. This is important for future regional transplant programs, and Georgian HLA and disease epidemiology and pharmacogenomics.

HLA genes in Wayu Amerindians from Colombia.

Amerindians origins and prehistory are still debated. HLA profile is different to all other World populations, although they have particular alleles in common with Asians, Australians and Pacific Islanders. In the present work, HLA-A, -B, -DRB1, -DQB1 alleles have been studied in Wayu Amerindians from Colombia. HLA alleles haplotypes, genetic distances and NJ dendrograms were calculated by Arlequin and DISPAN software. Only a few both class I and class II alleles have been observed. Most common extended haplotypes include: A*24-B*51-DRB1*0403-DQB1*0302, A*2-B*15-DRB1*1602-DQB1*0301, A*2-B*35-DRB1*0407-DQB1*0302, but also A*68-B*15-DRB1*0403-DQB1*0302. No trace of Caucasoid or Negroid admixture is detected. The Wayu HLA profile is typical from Amerindians and shows how languages and genes do not correlated particularly in this case (i.e., Wayu closest HLA genetic group is North Argentinian Guarani group). Results obtained in this work may be useful for future transplant programs and also for HLA linked diseases and individualized pharmacogenetics.

Efficacy of hepatitis B virus (HBV) DNA screening and characterization of acute and occult HBV infections among blood donors from Madrid, Spain.

BACKGROUND: Screening of blood units for hepatitis B virus (HBV) DNA identifies donations collected during the window period (WP) of the acute infection and may improve viral safety of the blood supply. It also leads to the detection of occult hepatitis B infection (OBI). STUDY DESIGN AND METHODS: From January 2005 to December 2006, a total of 383,267 blood units were screened for hepatitis B surface antigen (HBsAg) and HBV DNA in two transfusion centers in Madrid, using either individual-donation nucleic acid testing (ID-NAT) or minipool (MP-NAT) of eight donations (MP8). Samples positive for HBV DNA and negative for HBsAg were confirmed by a second molecular test, the viral DNA was quantified, and a genome fragment including the region encoding the major hydrophilic region (MHR) of HBsAg was sequenced. RESULTS: The overall yield of HBV DNA-positive, HBsAg-negative units was 1 in 21,282 (18 cases), higher when using ID-NAT than MP8-NAT (1:9862 vs. 1:51,011; p < 0.01). Four donations (1/95,817) were collected during the infectious pre-HBsAg WP, one during an early recovery stage, and the remaining 13 (1/29,482) were OBIs, six of whom had no detectable antibody to HBsAg. Low-level Genotype D HBV DNA was detected in all OBI cases; the frequencies of this genotype and MHR amino acid substitutions were significantly higher than reported from unselected Spanish HBsAg carriers. Donors with OBI had normal aminotransferase levels and were significantly older than donors carrying HBsAg. CONCLUSIONS: Blood donors in the WP and with OBI are not uncommon in Madrid and are detected at a higher frequency with ID-NAT than MP-NAT.

Peptidoglycan and mannose-based molecular patterns trigger the arachidonic acid cascade in human polymorphonuclear leukocytes.

The release of arachidonic acid (AA) in response to microorganism-derived products acting on pattern recognition receptors (PRR) was assayed in human polymorphonuclear leukocytes (PMN). Peptidoglycan (PGN) and mannan were found to be strong inducers of AA metabolism, as they produced the release of AA at a similar extent to that produced by agonists of pathophysiological relevance such as complement-coated zymosan particles and IgG immune complexes. In sharp contrast, lipoteichoic acid, LPS, muramyldipeptide, and the bacterial lipoprotein mimic palmitoyl-3-cysteine-serine-lysine-4 failed to do so. Leukotriene B4 and PGE2 were synthesized in response to mannan and PGN, thus suggesting that the lipoxygenase and the cyclooxygenase routes are operative in human PMN in response to pathogen-associated molecular patterns (PAMP). Analysis of the lipid extracts of supernatants and cell pellets as well as pharmacological studies with the calpain inhibitor calpeptin and the cytosolic phospholipase A2 (PLA2) inhibitor pyrrolidine-1 showed the dependence of AA release on cytosolic PLA2-catalyzed reactions. The effect of PGN was not inhibited by previous treatment with anti-TLR2 mAb, thus suggesting a nonarchetypal involvement of the TLR2 signaling route and/or participation of other receptors. Because of the abundance of mannose-based and PGN-containing PAMP in fungi and bacteria and the wide array of PRR in human PMN, these finding disclose a role of prime importance for PAMP and PRR in AA metabolism in the inflammatory response mediated by PMN.

Automated processing of whole blood units: operational value and in vitro quality of final blood components.

BACKGROUND: The Community Transfusion Centre in Madrid currently processes whole blood using a conventional procedure (Compomat, Fresenius) followed by automated processing of buffy coats with the OrbiSac system (CaridianBCT). The Atreus 3C system (CaridianBCT) automates the production of red blood cells, plasma and an interim platelet unit from a whole blood unit. Interim platelet unit are pooled to produce a transfusable platelet unit. In this study the Atreus 3C system was evaluated and compared to the routine method with regards to product quality and operational value. MATERIALS AND METHODS: Over a 5-week period 810 whole blood units were processed using the Atreus 3C system. The attributes of the automated process were compared to those of the routine method by assessing productivity, space, equipment and staffing requirements. The data obtained were evaluated in order to estimate the impact of implementing the Atreus 3C system in the routine setting of the blood centre. Yield and in vitro quality of the final blood components processed with the two systems were evaluated and compared. RESULTS: The Atreus 3C system enabled higher throughput while requiring less space and employee time by decreasing the amount of equipment and processing time per unit of whole blood processed. Whole blood units processed on the Atreus 3C system gave a higher platelet yield, a similar amount of red blood cells and a smaller volume of plasma. DISCUSSION: These results support the conclusion that the Atreus 3C system produces blood components meeting quality requirements while providing a high operational efficiency. Implementation of the Atreus 3C system could result in a large organisational improvement.

Short communication: RNASEL alleles and susceptibility to infection by human retroviruses and hepatitis viruses.

RNASEL seems to function as an intracellular restriction factor blocking the establishment of infections caused by viral agents. Herein, we investigated whether allelic variants at the RNASEL gene might influence the susceptibility to viral infections or conditions potentially linked to viral agents. The allelic distribution at codon 462 was 139 (33.9%), 204 (49.8%), and 67 (16.3%) for RR, RQ, and QQ, respectively, in 410 individuals in Spain. There were no significant differences comparing 105 blood donors and 71 patients with HIV-1 infection, 27 with chronic hepatitis C, 67 with prostate cancer, and 107 with chronic fatigue syndrome. In contrast, two-thirds of 18 patients with HTLV-1 infection and 15 with chronic hepatitis B harbored RR. Thus, polymorphisms at the RNASEL gene do not seem to influence the susceptibility to common viral infections or conditions potentially of viral etiology. The role in influencing the susceptibility to HTLV-1 or HBV chronic infection warrants further examination in larger patient populations.

Mannose-containing molecular patterns are strong inducers of cyclooxygenase-2 expression and prostaglandin E2 production in human macrophages.

The induction of cyclooxygenase-2 (COX-2) and the production of PGE(2) in response to pathogen-associated molecular patterns decorated with mannose moieties were studied in human monocytes and monocyte-derived macrophages (MDM). Saccharomyces cerevisiae mannan was a robust agonist, suggesting the involvement of the mannose receptor (MR). MR expression increased along the macrophage differentiation route, as judged from both its surface display assessed by flow cytometry and the ability of MDM to ingest mannosylated BSA. Treatment with mannose-BSA, a weak agonist of the MR containing a lower ratio of attached sugar compared with pure polysaccharides, before the addition of mannan inhibited COX-2 expression, whereas this was not observed when agonists other than mannan and zymosan were used. HeLa cells, which were found to express MR mRNA, showed a significant induction of COX-2 expression upon mannan challenge. Conversely, mannan did not induce COX-2 expression in HEK293 cells, which express the mRNA encoding Endo180, a parent receptor pertaining to the MR family, but not the MR itself. These data indicate that mannan is a strong inducer of COX-2 expression in human MDM, most likely by acting through the MR route. Because COX-2 products can be both proinflammatory and immunomodulatory, these results disclose a signaling route triggered by mannose-decorated pathogen-associated molecular patterns, which can be involved in both the response to pathogens and the maintenance of homeostasis.