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Oytip Nathalang,1 Kamonchanok Asisathaporn,1 Kamphon Intharanut,1 Wanlapa Chaibangyang,1 Nipapan Leetrakool,2 Supattra Mitundee,3 Sasitorn Bejrachandra4 1Graduate Program in Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand; 2Blood Bank Section, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; 3Regional Blood Centre 12th Songkhla, Thai Red Cross Society, Songkhla, Thailand; 4National Blood Centre, Thai Red Cross Society, Bangkok, ThailandCorrespondence: Oytip Nathalang, Graduate Program in Medical Technology, Faculty of Allied Health Sciences, Thammasat University, 99 Moo 18 Klongluang, Pathumthani, 12120, Thailand, Tel +662-9869213 Ext. 7231, Fax +662-5165379, Email oytipntl@hotmail.comPurpose: Coa and Cob antigens of the Colton (CO) blood group system are implicated in acute and delayed hemolytic transfusion reactions (HTRs). Owing to the inadequate supply of specific antiserum, data on CO phenotypes remain limited. This study aimed to develop genotyping methods to predict Coa and Cob antigens and to estimate transfusion-induced alloimmunization risks in three Thai blood donor populations.Materials and Methods: The study included 2451 blood samples from unrelated healthy Thai blood donors obtained from central, northern, and southern Thailand. DNA sequencing was used to determine the CO&ast;A and CO&ast;B alleles. In-house PCR with sequence-specific primers (PCR-SSP) and high-resolution melting curve (HRM) assays were performed and genotyping results were compared using DNA sequencing. CO&ast;A and CO&ast;B allele frequencies among Thais were determined using PCR-SSP and their frequencies were compared with other populations. The risks of Coa and Cob transfusion-induced alloimmunization among Thai donor populations were calculated.Results: The validated genotyping results by PCR-SSP and HRM assays agreed with DNA sequencing. The CO&ast;A/CO&ast;A was the most common (100.0, 100.0, and 99.3%), followed by CO&ast;A/CO&ast;B (0.0, 0.0, and 0.7%) among central, northern and southern Thais. Homozygous CO&ast;B/CO&ast;B was not found. The CO&ast;A and CO&ast;B allele frequencies among central Thais significantly differed compared among southern Thais (p < 0.01) but not among northern Thais. Those allele frequencies among Thais were similar to those of Taiwanese, Chinese and Malay-Malaysian populations but not to South Asian, Southeast Asian, Korean, Japanese, Filipino, French Basque, and Maltese populations (p < 0.01). A higher risk of anti-Cob production rather than anti-Coa production was particularly noted in the southern Thai population.Conclusion: This study constitutes the first to determine CO&ast;A and CO&ast;B genotypes using PCR-SSP and HRM assays among Thais and this finding would be beneficial in predicting alloimmunization risk and providing safe transfusions among Thais.Keywords: the Colton blood group system, genotypes, PCR-SSP, HRM, Thais

Background Major characteristics of the para-Bombay phenotype are the absence of ABH antigens on red blood cells due to fucosyltransferase 1 (FUT1) gene mutation and the presence of these antigens in body secretions due to the active fucosyltransferase 2 (FUT2) gene. An ABO blood group discrepancy can be identified via serological testing, and additional tests can be performed for confirmation. This study aimed to resolve the ABO discrepancy and report two novel alleles on the FUT2 gene in northern Thai para-Bombay families. Study design and methods Twelve blood samples were collected from five suspected para-Bombay donors and their families. Nucleotide sequences of ABO, FUT1, and FUT2 were analyzed by polymerase chain reaction-sequence-based typing. Bioinformatics tools were used to predict the effect of suspected novel FUT2 alleles. Results All samples exhibited normal ABO alleles, concordant with serological test results. FUT1 exhibited three known variants (c.328G>A, c.424C>T, and c.658C>T). Although FUT2 exhibited two known variants (c.357C>T and c.385A>T), two novel alleles were observed. One allele consisted of c.98A>G, c.101T>G, and c.357C>T with predicted normal transferase activity, whereas the other consisted of c.357C>T and c.617T>C with predicted abnormal enzyme activity. Discussion Two novel alleles in FUT2 were reported among the affected para-Bombay individuals of northern Thai families. The c.617T>C variant caused an amino acid change from valine to alanine at position 206, predicted to be an inactive FUT2 enzyme. Inheritance of this variant with the recessive FUT1 allele may lead to inheritance of the rare Bombay blood group in the progeny.

Purpose To determine the frequency and association of alleles at human leukocyte antigen (HLA)-DRB1 and HLA-DQB1 loci in VKH disease patients from Northern Thailand. Methods A case-control study was conducted with three subject groups: 23 VKH patients, 20 patients with other uveitis entities, and 40 healthy blood donors. HLA-DRB1 and HLA-DQB1 loci were analyzed and the frequency of HLA-DRB1 and HLA-DQB1 alleles was calculated by direct counting. The measure of association was calculated by odds ratio (OR) and 95% confidence interval. Results In VKH patients, the most prevalent allele was HLA-DRB1*04:05, found in 35% of patients and with the highest OR (42.13). HLA-DQB1*04:01 was the next most prevalent, found in 23.91% of VKH patients. HLA-DQB1*05:02 was also detected in 23.91% of patients; however, a higher prevalence was observed in non-VKH and healthy controls (30% and 35%, respectively). Conclusion HLA-DRB1*04:05 and HLA-DQB1*04:01 could be potential genetic markers for VKH.

Background SERF(+) is a high prevalence antigen in the Cromer blood group system that is encoded by a CROM*01.12 allele. The SERF(-) on red cells is caused by a single nucleotide variation, c.647C＞T, in exon 5 of the Decay-accelerating factor, DAF gene. Alloanti-SERF was found in a pregnant Thai woman, and a SERF(-) individual was found among Thai blood donors. Since anti-SERF is commercially unavailable, this study aimed to develop appropriate genotyping methods for CROM*01.12 and CROM*01.-12 alleles and predict the SERF(-) phenotype in Thai blood donors. Methods DNA samples obtained from 1,580 central, 300 northern, and 427 southern Thai blood donors were genotyped for CROM*01.12 and CROM*01.-12 allele detection using in-house PCR with sequence-specific primer (PCR-SSP) confirmed by DNA sequencing. Results Validity of the PCR-SSP genotyping results agreed with DNA sequencing; CROM*01.12/ CROM*01.12 was the most common (98.42%, 98.00%, and 98.59%), followed by CROM*01.12/CROM*01.-12 (1.58%, 2.00%, and 1.41%) among central, northern, and southern Thais, respectively. CROM*01.-12/CROM*01.-12 was not detected in all three populations. The alleles found in central Thais did not significantly differ from those found in northern and southern Thais. Conclusion This study is the first to distinguish the predicted SERF phenotypes from genotyping results obtained using in-house PCR-SSP, confirming that the CROM*01.-12 allele frequency ranged from 0.007 to 0.010 in three Thai populations. This helps identify the SERF(-) phenotype among donors and patients, ultimately preventing adverse transfusion reactions.

Background Two antithetical antigens, Doa and Dob of the Dombrock (DO) blood group system are implicated in acute to delayed hemolytic transfusion reactions among patients with anti-Doa or anti-Dob. Given the unavailability of specific antiserum, a polymerase chain reaction with sequence-specific primer (PCR-SSP) was developed to identify DO*A and DO*B alleles. This study aimed to determine DO*A and DO*B allele frequencies and to predict transfusion-induced alloimmunization risks in three Thai blood donor populations. Methods DNA samples obtained from 1,300, 300, and 400 blood donors from central, northern, and southern Thailand, respectively, were genotyped for the DO*A and DO*B allele detections using developed PCR-SSP. The results were confirmed by DNA sequencing. Results The validated genotyping results by PCR-SSP were in concordance with DNA sequencing. The DO*B/ DO*B was the most common genotype (77.0, 76.0, and 71.0%), followed by DO*A/DO*B (21.0, 22.7, and 25.2%) and DO*A/DO*A (2.0, 1.3, and 3.8%) among central, northern and southern Thais, respectively. The alleles found among central Thais showed significant differences from those found among southern Thais but not from those of northern Thais. The risk of anti-Doa production was higher than anti-Dob production among Thais. Concerning regional groups, the risk of Doa alloimmunization among southern Thais (0.2059) was higher than those among central (0.1771) and northern Thais (0.1824). Conclusions This was the first study to distinguish DO*A and DO*B genotypes in Thai populations using in-house PCR-SSP. This would be useful to predict alloimmunization risks that might result from transfusion-induced reactions of undetermined red cell antigens among blood donors and in reagent red cells.

Zika virus (ZIKV) is an emerging arbovirus with increasing prevalence in recent years. To reduce the risk of ZIKV transmission by transfusion, some mitigation strategies were recommended based on pathogen reduction technologies for blood products. In this study, we aimed to study the efficacy of several common pathogen reduction methods in the inactivation of ZIKV. The fresh frozen plasma and derivatives were spiked with a high titer of ZIKV or Sindbis virus (SINV). Viral titers and ZIKV RNA were measured before and after the inactivation treatment by methylene blue (MB), solvent/detergent (S/D), pasteurization, and low pH. The mean ZIKV infectivity titers in plasma and derivatives were 7.08 ± 0.14, 5.17 ± 0.14, 7.08 ± 0.14, and 5.80 ± 0.14 log10 TCID50 /mL, respectively before MB, S/D, pasteurization, and low pH inactivation. We found no detectable ZIKV RNA after five successive passages of inoculation on host cells, indicating there is no infectivity after inactivation. Similar inactivation results were observed for SINV. In conclusion, we achieved robust ZIKV inactivation through the four inactivation procedures in several blood products. These findings suggest that the pathogen reduction technologies commonly applied in plasma and derivatives have the capacity to mitigate the risk of ZIKV transmission by transfusion.

Cell-based therapy is a highly promising treatment paradigm in ischemic disease due to its ability to repair tissue when implanted into a damaged site. These therapeutic effects involve a strong paracrine component resulting from the high levels of bioactive molecules secreted in response to the local microenvironment. Therefore, the secreted therapeutic can be modulated by preconditioning the cells during in vitro culturing. Herein, we investigated the potential use of magnetic resonance imaging (MRI) probes, the “iron–quercetin complex” or IronQ, for preconditioning peripheral blood mononuclear cells (PBMCs) to expand proangiogenic cells and enhance their secreted therapeutic factors. PBMCs obtained from healthy donor blood were cultured in the presence of the iron–quercetin complex. Differentiated preconditioning PBMCs were characterized by immunostaining. An enzyme-linked immunosorbent assay was carried out to describe the secreted cytokines. In vitro migration and tubular formation using human umbilical vein endothelial cells (HUVECs) were completed to investigate the proangiogenic efficacy. IronQ significantly increased mononuclear progenitor cell proliferation and differentiation into spindle-shape-like cells, expressing both hematopoietic and stromal cell markers. The expansion increased the number of colony-forming units (CFU-Hill). The conditioned medium obtained from IronQ-treated PBMCs contained high levels of interleukin 8 (IL-8), IL-10, urokinase-type-plasminogen-activator (uPA), matrix metalloproteinases-9 (MMP-9), and tumor necrosis factor-alpha (TNF-α), as well as augmented migration and capillary network formation of HUVECs and fibroblast cells, in vitro. Our study demonstrated that the IronQ-preconditioning PBMC protocol could enhance the angiogenic and reparative potential of non-mobilized PBMCs. This protocol might be used as an adjunctive strategy to improve the efficacy of cell therapy when using PBMCs for ischemic diseases and chronic wounds. However, in vivo assessment is required for further validation.

Background: Cells-based therapy is a highly promising treatment paradigm in ischemic disease due to its ability to repair tissues when implanted into a damaged site. These therapeutic effects have been involving a strong paracrine component resulting from the high levels of bioactive molecules they secrete in response to the local microenvironment. Therefore, the secreted therapeutic can be modulated by preconditioning the cells during in vitro culture. Herein, we investigated the potential use of magnetic resonance imaging (MRI) probes “Iron-Quercetin complex” or IronQ for preconditioning peripheral blood mononuclear cells (PBMCs) to expand proangiogenic cells and enhance their secreted therapeutic factors. Methods: PBMCs obtained from healthy donor blood were cultured in the presence of the Iron-Quercetin complex. Preconditioning-PBMCs differentiated cells were characterized by immunostaining. An enzyme-linked immunosorbent assay to describe the secreted cytokines. In vitro migration and tubular formation using human umbilical vein endothelial cells (HUVECs) were completed to investigate the proangiogenic efficacy.Results: IronQ significantly increased mononuclear progenitor cells' proliferation and differentiation into the spindle-shape-like cells, expressing both hematopoietic and stromal cell markers. The expansion increased the number of colony-forming units (CFU-Hill). The conditioned medium obtained from IronQ-treated PBMCs contained a high level of Interleukin (IL)-8, IL-10, urokinase-type-plasminogen-activator (uPA), matrix metalloproteinases-9 (MMP-9), and tumor necrosis factor-alpha (TNF-α), and augmented migration and capillary network formation of HUVEC and fibroblast cells in vitro.Conclusions: Our study demonstrated that the IronQ-precondition PBMCs protocol could enhance the angiogenic and reparative potential of non-mobilized PBMCs. This protocol can be used as an adjunctive strategy to improve cell therapy's efficacy of PBMCs for ischemic diseases and chronic wound.

Introduction Recruiting blood donors remains a challenging process to ensure sufficient blood product supplies. There were several interventions implemented in order to promote the retention of first-time donors, including short messaging service (SMS). However, the efficacy of SMS for promoting the retention of blood donation has never been demonstrated in a randomized controlled trial. Here, we report the interim analysis of the TEXT study. Methods This is a single center, randomized- controlled trial. We enrolled participants 18 years of age or older who were first-time blood donors and who were able to read and understand text messages. Participants were excluded if the purposes of blood donation were as follows, autologous donation, apheresis or blood letting. Participants were also excluded if they had no cell phone number or lived temporarily in the area. Participants were randomized within 24 hours followed the blood donation in a 1:1 ratio (text group vs control group). Only participants who were allocated in the "text group'' would receive a computer-generated text message once his/her blood product was dispatched from the transfusion service. The content of text message was "We would like to inform you that your blood has been used for patients on DD.MM.YYYY. Because of your blood donation, patients' lives will be saved." The primary outcome of the study was the rate of returning for the second donation at 6 months. Odds ratio (OR) and 95% confidence interval (CI) for retention rate was calculated based-on a modified intention-to-treat analysis. Results In a modified intention-to-treat analysis, there were 867 participants allocated to the text group and 864 participants to the control group (Figure 1). Mean age was 26.1 (standard deviation, SD 9.2) and 26.2 (SD 9.4) years, respectively. The primary outcome occurred in 120 of 867 (13.8%) in the text group and 89 of 864 (10.3%) in the control group, OR 1.40 (95%CI 1.04 to 1.87, P-value=0.02). Number needed to treat was 29. Figure 2 demonstrates the Kaplan-Meier curves of participants who returned for the second blood donation comparing between text and control groups. The median time for returning was 119 days (interquartile range, 95.5-150.5) in text group and 119 days (interquartile range, 98-148) in control group. Subgroup analysis does not show significant interactions between participants' characteristics and outcome. Conclusion Among first-time blood donors, text messaging after blood product being dispatched is a simple, inexpensive and effective intervention to increase the retention rate for second donation at 6 months duration. Disclosures No relevant conflicts of interest to declare.

BACKGROUND S and s antigens of the MNS system are of clinical importance because alloanti-S and -s have usually caused delayed hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. Various red cell genotyping has been established to predict the phenotypes to solve serological test limitations. OBJECTIVES AND METHODS This study aimed to determine S and s genotype frequencies and to estimate the alloimmunization risks among central, northern and southern Thai populations. Altogether, 1237 blood samples from Thai blood donors were included. Only 150 samples were tested with anti-S and anti-s by indirect antiglobulin test. All samples were genotyped for GYPB*S and GYPB*s alleles using inhouse PCR with sequence-specific primer. Additionally, the allele frequencies were used to estimate alloimmunization risks and compare with other populations. RESULTS The phenotyping and genotyping results in 150 samples were in 100% concordance. The allele frequencies of GYPB*S in central, northern and southern Thais were 0.061, 0.040 and 0.097, and GYPB*s were 0.939, 0.960 and 0.903, respectively. The frequencies among central Thais were similar to those among northern Thai and Korean populations (P > 0.05) but significantly differed from those of Asian, Caucasian African American and Hispanic populations (P

Mixed-field agglutination (MFA) can be observed in forward typing of samples from A3 individuals with serologic ABO typing methods. The results of column agglutination testing (CAT) and tube agglutination testing using different antibody clones can be discordant. In this report, we reveal our experience using polymerase chain reaction–sequence-based typing (PCR-SBT) of ABO exon 7 to clarify serologic method discordance of A subgroup blood typing in Northern Thai donors. A total of 21 group A blood donors with either MFA or weak agglutination on routine ABO CAT were recalled. CAT was repeated with human and monoclonal anti-A, and tube agglutination testing with monoclonal anti-A and PCR-SBT of ABO exon 7 was performed. A total of 13 of the 21 donors returned, and ABO CAT with human anti-A was repeated. Eleven samples showed MFA suspected to be the A3 subgroup, and two samples showed 2+ strength suspected to be the Aweak subgroup. When tube agglutination testing using monoclonal antibody was performed, MFA was not observed in 9 of 11 samples with previously observed MFA from routine CAT, which were then interpreted as A2. From PCR-SBT performed in only exon 7 of the ABO gene, 7 of 13 sample results were consistent with ABO*A2 or ABO*AW alleles. Two samples suspected to be A2 or A3 had an ABO*AW allele. In two samples suspected to be Aweak, no mutation was detected in ABO exon 7, suggesting genetic variation elsewhere in the gene. Although other coding exons were not examined, in the alleles that could be assigned, ABO*A3 alleles were found less frequently than would be predicted from the serologic findings. These findings suggest that when MFA in routine CAT is observed, an A3 subgroup cannot be presumed. Caution should be exercised when MFA is noted in routine CAT. Immunohematology 2018;34:49–56.

BACKGROUND The reagent red blood cells used to screen and identify antibodies have to include K+ cells in all batch productions. The data of K/k phenotypes among differing Thai blood donor populations remains unknown; hence, mass screening for uncommon K+ donors by serological test has some limitations. Implementing K/k genotyping may be useful to predict uncommon K+ donors to overcome this challenge. This study aimed to establish an in-house K/k genotyping technique and to report KEL*01 and KEL*02 allele frequencies among three Thai blood donor populations to increase the selection of K+ donors in rare blood group databases. METHODS A total of 2,239 DNA samples obtained from 1,512 central, 427 southern, and 300 northern Thai blood donors were included. The KEL*01 and KEL*02 genotyping using PCR with sequence-specific primers (PCR-SSP) was developed and validated. All samples were genotyped using developed PCR-SSP. Moreover, the possibility of finding group O and predicted K+ phenotypes among Thai blood donor populations was calculated. RESULTS The DNA controls were validated using two sets of primer combinations and the results of KEL*01 and KEL*02 genotyping were in agreement. The KEL*01 allele frequencies were 0.0007, 0.0047, and 0.0000, and KEL*02 allele frequencies were 0.9993, 0.9953, and 1.0000 among central, southern, and northern Thai donors, respectively. In addition, mass screening among 3,795 and 566 donors in central and southern Thai populations was required to find at least one group O and predicted K+ phenotypes. CONCLUSIONS The in-house PCR-SSP for KEL*01 and KEL*02 genotyping provided reproducible and accurate results with cost effectiveness. Our results confirmed the low KEL*01 allele frequencies among Thais. PCR-SSP could be used as an alternative technique to simply increase the number of uncommon predicted K+ phenotypes for reagent red blood cell recruitments.

Background: Antigen-negative red cell transfusion is required for transfusion-dependent patients. We developed multiplex PCR for red cell genotyping and calculated the possibility of finding compatible predicted phenotypes in Thai blood donor populations according to red cell alloantibodies found among Thai patients. Methods: 600 DNA samples obtained from unrelated healthy central and northern Thai blood donors were tested with the newly developed multiplex PCR for FY*A, FY*B, JK*A, JK*B, RHCE*e, RHCE*E, DI*A and GYP*Hut, GYP*Mur, GYP*Hop, GYP*Bun, and GYP*HF allele detections. Additionally, the possibility of finding compatible predicted phenotypes in two Thai blood donor populations was calculated to estimate the minimal number of tests needed to provide compatible blood. Results: The validity of multiplex PCR using known DNA controls and the phenotyping and genotyping results obtained by serological and PCR-SSP techniques were in agreement. The possibility of finding at least one compatible blood unit for patients with multiple antibodies was comparable in Thai populations. Conclusions: The multiplex PCR for red cell genotyping simultaneously interprets 7 alleles and 1 hybrid GP group. Similar strategies can be applied in other populations depending on alloantibody frequencies in transfusion-dependent patients, especially in a country with limited resources.

Mixed-field agglutination (MFA) can be observed in forward typing of samples from A3 individuals with serologic ABO typing methods. The results of column agglutination testing (CAT) and tube agglutination testing using different antibody clones can be discordant. In this report, we reveal our experience using polymerase chain reaction-sequence-based typing (PCR-SBT) of ABO exon 7 to clarify serologic method discordance of A subgroup blood typing in Northern Thai donors. A total of 21 group A blood donors with either MFA or weak agglutination on routine ABO CAT were recalled. CAT was repeated with human and monoclonal anti-A, and tube agglutination testing with monoclonal anti-A and PCR-SBT of ABO exon 7 was performed. A total of 13 of the 21 donors returned, and ABO CAT with human anti-A was repeated. Eleven samples showed MFA suspected to be the A3 subgroup, and two samples showed 2+ strength suspected to be the Aweak subgroup. When tube agglutination testing using monoclonal antibody was performed, MFA was not observed in 9 of 11 samples with previously observed MFA from routine CAT, which were then interpreted as A2. From PCR-SBT performed in only exon 7 of the ABO gene, 7 of 13 sample results were consistent with ABO*A2 or ABO*AW alleles. Two samples suspected to be A2 or A3 had an ABO*AW allele. In two samples suspected to be Aweak, no mutation was detected in ABO exon 7, suggesting genetic variation elsewhere in the gene. Although other coding exons were not examined, in the alleles that could be assigned, ABO*A3 alleles were found less frequently than would be predicted from the serologic findings. These findings suggest that when MFA in routine CAT is observed, an A3 subgroup cannot be presumed. Caution should be exercised when MFA is noted in routine CAT.

Background: Human neutrophil antigens (HNAs) are involved in autoimmune and alloimmune neutropenia and transfusion-related acute lung injury. The HNA-1 system is important in immunogenetics, and allele frequencies have been described in different populations. This study investigated the frequency of FCGR3B alleles encoding HNA-1a, HNA1b, and HNA-1c among Thai blood donors and compared these frequencies with those previously reported for other populations. Methods: Eight hundred DNA samples obtained from unrelated healthy blood donors at the National Blood Centre, Thai Red Cross Society, Bangkok, and the Blood Bank, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand, were included. Samples were simultaneously typed for each FCGR3B allele using an in-house polymerase chain reaction with sequence-specific primer (PCR-SSP) technique. Results: The frequencies of FCGR3B*1, FCGR3B*2, and FCGR3B*3 alleles in central Thai blood donors were 0.548, 0.452, and 0.004, respectively; only FCGR3B*1 and FCGR3B*2 alleles were found in northern Thai blood donors (0.68 and 0.32, respectively). Compared with other Asian populations, central Thais had higher frequencies of the FCGR3B*2 allele (P

The CD45 antigen is essential for normal antigen receptor-mediated signalling in lymphocytes, and different patterns of splicing of CD45 are associated with distinct functions in lymphocytes. Abnormal CD45 splicing has been recognized in humans, caused by a C77G transversion in the gene encoding CD45 (PTPRC). Recently the C77G polymorphism has been associated with multiple sclerosis and increased susceptibility to HIV-1 infection. These studies suggest that the regulation of CD45 splicing may be critical for the proper function of the immune system. Because of these data we examined the frequency of the C77G allele in African and Asian populations from countries with high or low prevalence of HIV infection. Here we report that the variant CD45 C77G allele is absent in African populations. We further show that populations living in the Pamir mountains of Central Asia have a very high prevalence of the C77G variant.

Abdominal compartment syndrome (ACS) is a life-threatening condition which can occur in patients with hemophilia although they have trivial traumas. Hemostatic control for bleeding episodes in hemophilia patients with inhibitors is difficult particularly when the availability of bypassing agents, recombinant activated factor VII (rFVIIa) and activated prothrombin complex concentrate (APCC), is constrained. Plasma exchange with continuous infusion of factor concentrate has been reported as a life-saving intervention in these patients. We reported a teenager with severe hemophilia A and a high-titer inhibitor who underwent two surgeries for ACS which developed after a minor trauma. Computerized tomography angiogram (CTA) of abdomen revealed a large pelvic hematoma and a bleeding from the sigmoidal artery. He underwent an abdominal angiography followed by the first surgery to relieve the ACS, and the second surgery for abdominal closure. The patients received plasma exchange with cryo-removed plasma peri-operatively. High-dose factor VIII (FVIII) concentrate (100 U/kg) was started after plasma exchange followed by continuous infusion at the rate 14 units/kg/hour for 7 days. rFVIIa and APCC concomitant with tranexamic acid were used for breakthrough bleeding. He received six times of plasma exchange, three doses of rFVIIa and five doses of APCC. Bleeding was successfully stopped and the titers of inhibitor decreased from the maximum of 4,400 BU to 3,680 BU. Plasma exchange and continuous FVIII infusion can be considered as an option for life-threatening hemorrhage in hemophilia patients with high-titer inhibitors in the countries where an access to bypassing agents is limited.

Screening of blood donors with nucleic acid testing (NAT) for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) has been implemented recently in the United States. There are limited data however on the additional NAT yield of donors in developing countries in Asia where the prevalence of infection is higher. In addition data on hepatitis B virus (HBV) NAT in high prevalence areas are minimal. A total of 5083 whole-blood donors at the Chiang Mai University Hospital Thailand blood bank were evaluated with a commercially available NAT assay (Procleix Ultrio Gen-Probe Inc.) to screen individual donations. No NAT yield cases were found for HIV-1 or HCV. There were 17 samples with discrepant HBV DNA NAT and hepatitis B surface antigen (HBsAg) tests however. Seven of these were HBV DNA NAT-positive HBsAg-negative; of these 7 1 was NAT-positive at baseline but negative on follow-up and considered a false-positive 1 had an acute infection and 5 had chronic prevalent HBV infections for a NAT yield of 6 in 4798 HBsAg negative donors (1:800). In addition there were 10 NAT-negative HBsAg-positive serum samples. All were anti-hepatitis B core antigen immunoglobulin G-positive; on testing with a more sensitive NAT target capture assay 5 were positive (1.8-20.6 I/mL) and 5 were negative. Multiplex NAT screening of individual-donor serum samples in Northern Thailand detected approximately 1 per 800 HBV NAT-positive HBsAg-negative donors. The especially high prevalence of HBV infection in Thailand and other Asian countries suggests that HBV NAT screening of donors will be more cost-effective than in other areas. (authors)

Severe transfusion-related acute lung injury (TRALI) is often due to antibodies in blood components directed against human neutrophil antigen (HNA)-3a. This study aimed to report the genotype frequencies of the HNA-3 system and to estimate the potential risk of HNA-3 incompatibility and alloimmunization in two Thai populations. Eight hundred DNA samples obtained from 500 unrelated healthy blood donors at the National Blood Centre, Thai Red Cross Society, Bangkok and 300 samples from the Blood Bank, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand were included. HNA-3 genotyping was performed using an in-house polymerase chain reaction with sequence-specific primer (PCR-SSP) technique. The observed frequencies of the HNA-3a/3a, HNA-3a/3b, and HNA-3b/3b genotypes were 0.528, 0.380, and 0.092 in central Thais and 0.600, 0.350, and 0.050 in northern Thais, respectively. The frequencies were used to estimate HNA-3 incompatibility and risk of HNA-3a alloimmunization. The HNA-3 incompatibility in central Thais (33.28%) was higher than northern Thais (28.75%), corresponding to a significantly higher probability of HNA-3a alloimmunization (P

Background We present Kidd blood group allele frequencies in Thai blood donors and compare them with other frequencies for other populations previously reported. Methods Eight hundred blood samples obtained from 500 central Thais and 300 northern Thais were genotyped by allele specific-PCR. Results It was found that JK*01 and JK*02 allele frequencies were 0.503 and 0.497 in central Thais, while the frequencies were 0.498 and 0.502 in northern Thais. The JK*01 and JK*02 allele frequencies in Thais were similar to those in Chinese populations, whereas the frequencies were significantly different from Japanese, French Basques, and African-Americans. Conclusions This is the first to report of Kidd blood group allele frequencies in Thais, which is beneficial for the prevention of both alloimmunization and adverse transfusion reactions.

A self-deferral form has been used to screen Chiang Mai University Hospital blood donors and was improved in 2005. It has never been evaluated. The study aimed to assess the self-deferral form procedures in detecting infected donors. Sera from 5,083 donors, who passed the self-deferral screening form, were tested with the routine immuno-assays (serology) for HIV 1 and 2 antibodies, P24 antigen, HCV antibodies, HBV surface antigen, and syphilis. Antibody negative sera were also tested individually with the the Procleix Ultrio Assay for HIV-1 DNA, HCV RNA, and HBV DNA. The donors who had discrepant results between serology and NAT were evaluated with additional tests, including a more sensitive Alternative Nucleic Acid Test, AntiBcore IgM, AntiBcore IgG, HBsAg and Anti HBs. Among 5,083 donors, 331 (6.5%) had at least one positive marker. In multiple logistic regression analysis, the statistically significant factors (adjusted odds ratio and 95% CI) for infection were age 30 years or below [1.45 (1.03, 2.03)], male gender [2.73 (1.64, 4.56)], primary school or lower education [1.56 (1.09, 2.23)], first-time donation [1.82 (1.25, 2.67)], and frequent donation [0.80 (0.70, 0.92)]. The safest donors were females, older than 30 years, with an education more than primary school, and frequent donation. Because of missing responses to some sensitive questions, there remains a need for further improvement of the self-deferral form.

Screening of blood donors with nucleic acid testing (NAT) for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) has been implemented recently in the United States. There are limited data, however, on the additional NAT yield of donors in developing countries in Asia where the prevalence of infection is higher. In addition, data on hepatitis B virus (HBV) NAT in high prevalence areas are minimal.A total of 5083 whole-blood donors at the Chiang Mai University Hospital, Thailand, blood bank were evaluated with a commercially available NAT assay (Procleix Ultrio, Gen-Probe, Inc.) to screen individual donations.No NAT yield cases were found for HIV-1 or HCV. There were 17 samples with discrepant HBV DNA NAT and hepatitis B surface antigen (HBsAg) tests, however. Seven of these were HBV DNA NAT-positive, HBsAg-negative; of these 7, 1 was NAT-positive at baseline, but negative on follow-up, and considered a false-positive, 1 had an acute infection, and 5 had chronic prevalent HBV infections, for a NAT yield of 6 in 4798 HBsAg negative donors (1:800). In addition there were 10 NAT-negative, HBsAg-positive serum samples. All were anti-hepatitis B core antigen immunoglobulin G-positive; on testing with a more sensitive NAT target capture assay, 5 were positive (1.8-20.6 IU/mL) and 5 were negative.Multiplex NAT screening of individual-donor serum samples in Northern Thailand detected approximately 1 per 800 HBV NAT-positive, HBsAg-negative donors. The especially high prevalence of HBV infection in Thailand and other Asian countries suggests that HBV NAT screening of donors will be more cost-effective than in other areas.

Acute anterior uveitis (AAU) is the most frequent type of uveitis encountered in the west. Although human leucocyte antigen (HLA)-B27-associated ankylosing spondylitis was reported in South East Asia, it is not known whether HLA-B27-associated ocular disease is prevalent in Thailand.A prospective study of 100 unrelated blood donors and 121 consecutive patients with AAU was carried out. All people underwent HLA-B27 typing and full ocular examination. Radiological examination of the sacroiliac joints was conducted in patients with low back pain or arthralgias.The prevalence of HLA-B27 was 10% among the blood donors in contrast with 44% in the AAU group (p0.001). The clinical characteristics of HLA-B27-associated AAU were similar to those published throughout the world (unilaterality in 74%, hypopyon in 31%, recurrent AAU in 64%). However, the increased intraocular pressure (IOP) was more common in the HLA-B-27-negative group (p = 0.03) than in their HLA-B27-positive counterparts. At least 15% of the HLA B27-positive group had radiological signs of ankylosing spondylitis.The prevalence of HLA-B27 in the population without uveitis in Thailand is about 10% and clinical characteristics of HLA-B27-positive AAU are similar to those reported in the west. In contrast with earlier reports, HLA-B27-negative AAU in Thailand was associated with increased IOP and should be further studied.

CD45 is crucial for normal lymphocyte signalling, and altered CD45 expression has major effects on immune function. Both mice and humans lacking CD45 expression are severely immunodeficient, and single-nucleotide polymorphisms in the CD45 gene that cause altered splicing have been associated with autoimmune and infectious diseases. Recently, we identified an exon 6 A138G polymorphism resulting in an increased proportion of activated CD45RO T cells and altered immune function. Here we report a significantly reduced frequency of the 138G allele in hepatitis C Japanese patients and a possibly reduced frequency in type I diabetes. The allele is widely distributed in the Far East and India, indicating that it may have a significant effect on disease burden in a large part of the human population.

The polymorphism of 15 short tandem repeat (STR) loci-D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA from AmpFlSTR Identifiler PCR amplification kit were analysed in 929 unrelated individuals living in the north, northeast, central and south of Thailand. The comparison between these four subpopulations demonstrated that subpopulations in the north and northeast were different in two loci from all paired groups while those in the north, central and south were closely related. The inter-population comparisons between combined Thai population and other ethnic groups including Eastern Chinese, Japanese, Iraq and Egyptian revealed that Eastern Chinese and Thai were closely related.