Assessing opportunities and challenges for establishing a national program to distribute cord blood for research.

BACKGROUND: Research is needed to enhance cord blood (CB) transplantation outcomes and to develop new clinical applications. Based on quality criteria for transplantation, CB collected by public CB banks (CBBs) is often unsuitable for banking, but may still be valuable for research. Canadian researchers have described a need for a centralized program providing ethically sourced CB for research projects. To meet this need, Canadian Blood Services (CBS), in partnership with The Ottawa Hospital, launched the Cord Blood for Research Program (CBRP) in 2014. STUDY DESIGN AND METHODS: The CBRP developed processes for donor research consent and research project approval with oversight from CBS's CBB and appropriate research ethics boards. The CBRP distributes deidentified CB products to research projects across Canada. RESULTS: Since its inception, the CBRP has distributed more than 525 CB units to researchers, supporting 11 research projects. Of the mothers who donate their baby's CB, 77% have chosen to consent to its use for research if it is not bankable. The number of CB units currently available for research via the CBRP exceeds the requests from researchers. CONCLUSION: The CBRP reliably distributes quality CB products that do not qualify for banking to investigators across Canada in an ethical, legal, and transparent manner. This provides an opportunity for the public to directly support research, helps meet the need expressed by Canada's research community, and maximizes the donor's gift. More research is needed to clarify the factors influencing donor and researcher participation in the CBRP.

Process improvement by eliminating mixing of whole blood units after an overnight hold prior to component production using the buffy coat method.

The elimination of a thorough manual mixing of whole blood (WB) which takes place following the overnight hold, but before the first centrifugation step, during buffy coat component production at Canadian Blood Services (CBS) was investigated. WB was pooled after donation and split. Pairs of platelet, red blood cell (RBC), and plasma components were produced, with half using the standard method and half using a method in which the mixing step was eliminated. Quality assessments included yield, pH, CD62P expression and morphology for platelets, hemoglobin, hematocrit, hemolysis, and supernatant K(+) for RBCs, and volume and factor VIII activity levels for plasma. All components, produced using either method, met CBS quality control criteria. There were no significant differences in platelet yield between components produced with and without mixing. A significant difference was seen for RBC hemolysis at expiry (P = 0.03), but for both groups, levels met quality control requirements. Noninferiority of components produced without mixing was confirmed for all parameters. Manual mixing is laborious and has a risk of repetitive strain for production staff and its significance is unclear. Elimination of this step will improve process efficiencies without compromising quality.

Evaluating the 4-hour and 30-minute rules: effects of room temperature exposure on red blood cell quality and bacterial growth.

BACKGROUND: A 30-minute rule was established to limit red blood cell (RBC) exposure to uncontrolled temperatures during storage and transportation. Also, RBC units issued for transfusion should not remain at room temperature (RT) for more than 4 hours (4-hour rule). This study was aimed at determining if single or multiple RT exposures affect RBC quality and/or promote bacterial growth. STUDY DESIGN AND METHODS: Growth and RT exposure experiments were performed in RBCs inoculated with Serratia liquefaciens and Serratia marcescens. RBCs were exposed once to RT for 5 hours (S. liquefaciens) or five times to RT for 30 minutes (S. marcescens) with periodic sampling for bacterial counts. Noncontaminated units were exposed to RT once (5 hr) or five times (30 min each) and sampled to measure in vitro quality variables. RBC core temperature was monitored using mock units with temperature loggers. Growth and RT exposure experiments were repeated three and at least six times, respectively. Statistical analysis was done using mixed-model analysis. RESULTS: RBC core temperature ranged from 7.3 to 11.6°C during 30-minute RT exposures and the time to reach 10°C varied from 22 to 55 minutes during 5-hour RT exposures. RBC quality was preserved after single or multiple RT exposures. Increased growth of S. liquefaciens was only observed after 2 hours of continuous RT exposure. S. marcescens concentration increased significantly in multiple-exposed units compared to the controls but did not reach clinically important levels. CONCLUSION: Single or multiple RT exposures did not affect RBC quality but slightly promoted bacterial growth in contaminated units. The clinical significance of these results remains unclear and needs further investigation.

Evaluation of the sterility testing process of hematopoietic stem cells at Canadian Blood Services.

BACKGROUND: Sterility testing of hematopoietic stem cells (HSCs) at The Canadian Blood Services Stem Cell Laboratory is performed using BacT/ALERT aerobic (SA) culture bottles. This study was conducted to verify the efficacy of this method and to assess the use of the BacT/ALERT aerobic (BPA) and anaerobic (BPN) culture bottles for microbial testing of HSCs. STUDY DESIGN AND METHODS: HSC products, including cryopreserved apheresis peripheral blood, marrow, and cord blood and fresh cord blood, were spiked with four aerobic organisms including Staphylococcus epidermidis, Bacillus cereus, Pseudomonas aeruginosa, and Candida albicans, and the anaerobe Bacteroides fragilis at a target concentration of 100 colony-forming units (CFUs)/mL. One to 2 mL of pre- and postspiked samples was inoculated into SA, BPA, and BPN bottles in duplicate and incubated for 5 to 10 days. The presence of the testing organisms in positive culture bottles was confirmed by plating on blood agar. RESULTS: The BacT/ALERT system detected the aerobic organisms in all HSCs in SA and BPA bottles within 34.1 hours while B. fragilis was detected only in BPN bottles within 68.6 hours. The mean recovered concentration of microorganisms in the HSC products ranged from 55 to 352 CFUs/mL with the exception of B. cereus, which was greater than 10(3) CFUs/mL. CONCLUSION: This study shows that the current sterility testing process at the Canadian Blood Services Stem Cell Laboratory detected the tested aerobic but not the anaerobic microbial contaminants in HSCs. The ability of the BacT/ALERT system using BPA and BPN bottles to detect bacterial contamination in HSCs was also demonstrated.

Changes in coagulation factor activity and content of di(2-ethylhexyl)phthalate in frozen plasma units during refrigerated storage for up to five days after thawing.

BACKGROUND: Thawed plasma is typically transfused to supply coagulation factors but factor activity declines during refrigerated storage. Refrigerating thawed plasma for longer than 24 hours could reduce plasma wastage and make plasma more readily available for emergency transfusions. We measured coagulation factor activity and di(2-ethylhexyl)phthalate (DEHP) concentration in frozen plasma (FP) thawed and stored at 1 to 6°C for up to 5 days. STUDY DESIGN AND METHODS: FP units prepared using "top-and-bottom" collection sets were thawed, refrigerated, and sampled aseptically at 0, 24, 72, and 120 hours after thawing (n = 54). Clotting factor activities and prothrombin times (PTs) were measured using an automated coagulation factor analyzer. DEHP was measured by high-performance liquid chromatography after hexane extraction (n = 11). Unit sterility was confirmed using an automated microbial detection system. RESULTS: Factor (F)V and FVIII, but not FVII, declined significantly within 24 hours. By Day 5, mean losses were 20, 14, and 41%, in FV, FVII, and FVIII, respectively; fibrinogen activity did not change. PT values were prolonged by 9% on Day 5. Mean DEHP levels increased from 22 ppm at thaw to 66 ppm on Day 5. CONCLUSIONS: The bulk of coagulation factor activity losses during storage occurred in the first 24 hours. Coagulation factor activities remaining in FP after 5 days did not differ from those previously reported in similar products frozen within 24 hours of phlebotomy. While DEHP levels in 5-day-thawed FP are not of concern for adult patients, for infants, DEHP levels can be minimized by using FP refrigerated for no more than 24 hours.

Bacterial screening of outdated buffy coat platelet pools using a culture system and a rapid immunoassay.

BACKGROUND: Canadian Blood Services performs bacterial screening of buffy coat platelet pools (BCPs) using aerobic BacT/ALERT cultures. This study aimed to determine the rate of detection failures during initial platelet (PLT) screening and evaluate the introduction of anaerobic cultures and immunoassay testing to assess the safety of extending PLT storage beyond 5 days. STUDY DESIGN AND METHODS: Outdated (7- to 10-day-old) BCPs that tested negative during initial screening were assayed with BacT/ALERT and the Verax PLT Pan Genera detection (PGD) test, an immunoassay that detects Gram-positive (GP) and Gram-negative (GN) bacteria. BacT/ALERT aerobic and anaerobic culture bottles were inoculated with 8 to 10 mL of BCP and incubated for up to 6 days. The PGD test was performed following manufacturer's instructions. Positive results were confirmed using the BacT/ALERT and PGD tests, blood agar culture, and Gram staining. Invalid PGD results were investigated. RESULTS: A total of 4002 BCPs were tested with one (0.025%) true positive (Staphylococcus epidermidis) found by both the BacT/ALERT and the PGD assays. Fifty-four (1.35%) false-positive BacT/ALERT cultures were obtained mainly due to instrument errors involving anaerobic cultures. Eleven (0.27%) false-positive PGD tests were observed in the GP window of the strip. Forty-nine (1.2%) invalid PGD results were obtained mostly before implementation of a humidity chamber. CONCLUSION: Testing of outdated BCPs suggests that introducing anaerobic cultures would result in significant PLT wastage due to a high rate of false positives. Contaminated BCPs still escape detection during initial testing; therefore, extension of PLT storage may be possible if repeat screening is performed before transfusion.

Evaluation of the BacT/ALERT 3D system for the implementation of in-house quality control sterility testing at Canadian Blood Services.

BACKGROUND: Until recently, Canadian Blood Services (CBS) was performing quality control sterility testing of blood components using three different processes. This study was conducted in order to standardize sterility testing at all CBS centers in a cost-effective manner using the BacT/ALERT 3D system. METHODS: Blood components including fresh frozen plasma, platelet concentrates, and red blood cells were inoculated with eight bacterial species at target concentrations of 1 and 10 CFU/mL. Pre- and post-spiked samples were inoculated into BacT/ALERT aerobic and anaerobic culture bottles and incubated for a maximum of 10 days. Specificity of the positive culture bottles was verified by Gram staining. Positive results obtained pre- and post-implementation of the in-house sterility testing program at CBS were collected and analyzed. RESULTS: The BacT/ALERT3D system detected all bacteria in all blood components tested in this validation. Positive cultures were obtained within 28 h of incubation with the exception of Propionibacterium acnes which was detected within 134 h. The percentage of positive cultures ranged from 0.01% to 0.2%. All contaminants isolated were either normal skin flora or environmental microorganisms. CONCLUSIONS: This study demonstrates the capability of the BacT/ALERT3D system to detect aerobic and anaerobic bacterial contamination in all tested blood components, thereby supporting its use for quality control sterility testing and not only bacterial screening. A standardized process will allow CBS to evaluate and compare blood collection and manufacturing practices across the country.

Assessment of biofilm-forming ability of coagulase-negative staphylococci isolated from contaminated platelet preparations in Canada.

BACKGROUND: Coagulase-negative staphylococci (CoNS) are the most prevalent bacterial contaminants of platelet (PLT) preparations and have been implicated in adverse transfusion reactions worldwide. The most frequently identified contaminant is Staphylococcus epidermidis, which is noted for its ability to maintain chronic hospital-acquired infections by forming biofilms as a chief virulence mechanism. STUDY DESIGN AND METHODS: Strains of S. epidermidis isolated from contaminated PLT preparations in Canada were distinguished via gene-specific polymerase chain reaction (PCR) with divIVA as a marker. Biofilm-forming ability was assessed by the presence of the gene icaD, slime production on Congo red agar, and biofilm formation on polystyrene surfaces. Production of polysaccharide intercellular adhesin (PIA) was resolved by immunofluorescence. RESULTS: Eight of the 13 (62%) CoNS isolates under study were identified as S. epidermidis. Of these, four strains (50%) were classified as strong biofilm producers. Three of the four biofilm-positive strains (75%) produced slime, harbored the icaD gene, and had positive expression of PIA. CONCLUSIONS: Despite the presumable commensal origin of the CoNS isolates, a large proportion of S. epidermidis strains demonstrated a potential for enhanced virulence. Identification of contaminant staphylococci as biofilm producers is thus relevant and informative with regard to treatment approach in the circumstance of inadvertent infection of a PLT recipient.

Quantitative PCR for detection and discrimination of the bloodborne pathogen Staphylococcus epidermidis in platelet preparations using divIVA and icaA as target genes.

Bacterial contamination of blood components is the major microbiological cause of transfusion-associated morbidity, with Staphylococcus epidermidis being the most frequently isolated organism from contaminated platelet preparations (PPs). We have recently shown that S. epidermidis forms biofilms during platelet storage, which might account for reported missed detection during routine screening. In this study, we developed a highly sensitive and specific multiplex quantitative PCR (QPCR) assay to detect S. epidermidis in PPs at levels of 10(2)-10(3) cfu/mL. A specific primer pair and hydrolysis probe were designed to amplify an internal region of the cell division divIVA gene that is unique to S. epidermidis. In addition, an internal sequence of the virulence gene icaA, which is involved in the synthesis of the S. epidermidis biofilm matrix, was selected to allow for differentiation of potentially biofilm-forming S. epidermidis isolates. A conserved region of the 8 alleles of the HLA-DQalpha1 locus present in residual white blood cells in PPs was selected as an internal control for the assay. The specificity of this assay was confirmed, as other staphylococcal species that were tested with the optimized parameters were not detected. This QPCR assay could be adaptable for the detection of other bloodborne bacterial pathogens.