Blood screening is an essential step to ensure blood safety by reducing the risk of transfusion-transmitted infectious. Due to the increasing number of viral markers targeted and the use of assays with highly analytical sensitivity, the effectiveness of blood screening has improved significantly. However, the loss of qualified blood donors due to false positive results has attracted widespread concern. With the continuous development of detection methods, laboratory technical specifications and diagnostic guidelines for infections caused by blood-borne pathogens have also been constantly updated. The consensus recommendations proposed here systematically elaborates on key elements of markers and detection of pathogens transmitted through transfusion, confirmation of infection, and donor deferral criteria. Relevant national and international studies on blood screening, as well as previously published guidelines, standards and consensus statements, and the current situation in China, are also taken into consideration. The level of evidence and the quality of recommendations are scientifically evaluated using the GRADE framework (Grading of Recommendations, Assessment, Development, and Evaluation). The consensus aims to ensure transfusion safety by permanently excluding infected individuals, while preserving the rights and interests of blood donors by maintaining the eligibility assessment of individuals who are not infected or whose infection is not confirmed, thereby reducing donor loss.

Objective: To investigate the incidence, characteristics, and influencing factors of resolution discrepancies within the minipool (MP) testing model across Chinese blood station laboratories in 2024. Methods: A nationwide, multicenter, cross-sectional study was conducted, including 334 blood station laboratories that reported nucleic acid reactive data among enzyme immunoassay non-reactive samples. Of these, 296 laboratories adopted the pool resolution model, with a total of 12 536 273 samples tested. Systematic analysis was performed on resolution data, focusing on the MP-NAT reactivity rate, the pool resolution concordance rate, and the resolution discrepancy rate. Subgroup analyses were conducted based on reagent types, viral targets, and Ct values. Potential causes were further explored through laboratory surveys and re-examination of raw amplification curves. Results: In 2024, the national average MP-NAT reactivity rate was 0.15%. The overall pool resolution concordance rate was 57.86%, which showed a gradual decline as Ct values increased across all reagents. The national average resolution discrepancy rate was 0.081‱(102/12 536 273), with 17.91%(53/296) of laboratories reporting at least one discrepancy. Nine reagent types were associated with these events, exhibiting reagent-specific patterns. For Reagent A2, the predominant discrepancy was HBV reactive pools resolving as HIV (36.36%); for Reagent D1, HBV pools frequently resolved as HCV (38.89%); and for Reagent E, the most common pattern was HIV pools resolving as HBV (48.00%). These resolution discrepancies were strongly associated with high Ct values: the median pool Ct for HBV exceeded 38, while those for HCV and HIV both exceeded 40. Investigations across 16 laboratories revealed that most discrepant samples exhibited “tailing” amplification curves, with some cases linked to cross-contamination or reagent batch-specific issues. Conclusion: While the incidence of resolution discrepancies in the MP-NAT model remains low in China, variations exist across different reagents and laboratories. These discrepancies are closely associated with low viral load, reagent performance, and laboratory operational practices.

Objective: To establish evidence-based, safe and efficient management of HIV-reactive blood donors by investigating safe and feasible assessment strategies for HIV-reactive blood donors based on routine blood screening data. Methods: The data of blood screening, supplementary testing, follow-up and CDC confirmation for HIV-reactive blood donors in our center from 2014 to 2024 were analyzed systematically to confirm HIV infection and identify infection status. Results: There were 1 235 samples (0.13%, 1 235/928 000) reactive in HIV blood screening over the 11-year period. A-mong them, 199 donors (16.11%) in asymptomatic HIV infection (HIV Ag/Ab++&HIV RNA+), 2(0.16%) as acute early HIV infection (HIV Ag/Ab+-&HIV RNA+) and 7(0.57%) as window-period infection (HIV RNA positive only) were confirmed. Donors with the result of HIV Ag/Ab+-&HIV RNA-(single-positive) were all excluded for HIV infection, while 1 in 6 HIV Ag/Ab++&HIV RNA-donors (double-positive) was confirmed to have HIV infection. When HIV Ag/Ab reagents were used continuously before and after the follow-up, it's observed in one reagent that the proportion of negative results in subsequent follow-up in single-positive donors who had negative results in the first sampling was significantly higher than the proportion of negative results in subsequent follow-up in those initially single-positive (P<0.05). But no significant difference was observed in another reagent (P>0.05). When reagents were changed in follow-up, the rate of singlepositive donors with negative results in the first sampling reached 96.7%, which was significantly higher than the negative rate of those without reagent changing in follow-up (P<0.05). Conclusion: Based on the serological and nucleic acid testing results of HIV blood screening, the confirmation of HIV infection and identification of infection status can be achieved accurately and efficiently. All HIV Ag/Ab+-&HIV RNA-donors were confirmed as false positive, and should be maintained their eligibilities for blood donation, but recommended to pass the retest before next donation. Using a different reagent for retesting helps improve the eligible rate. HIV Ag/Ab++&HIV RNA-donors should be deferred permanently due to the risk of true positivity.

Objective: To explore a simple, effective, and safe method for excluding false positives and identifying infections by comprehensively evaluating blood donors with reactive HIV screening results, thereby providing a basis for developing management strategies for such donors. Methods: HIV testing data of blood donors from our laboratory from January 2022 to December 2024 were collected. The results of ELISA and nucleic acid testing (NAT) were combined with confirmatory results from the CDC and analyzed. Results: A total of 605 929 samples were tested for HIV over the three-year period, with 682 reactive samples (reactive rate: 11.25 per 10 000). All were sent to the CDC for Western blot (WB) confirmation, resulting in 53 confirmed positives ((confirmed positive rate: 7.77%). Among these, 619 samples showed isolated HIV Ag&Ab reactivity with non-reactive NAT (HIV Ag&Ab+-&HIV RNA or NAT NR), with a confirmed infection rate of 0%; 9 samples showed dual HIV Ag&Ab reactivity with non-reactive NAT (HIV Ag&Ab++&HIV RNA NR or NAT NR), also with 0% confirmed infection; 52 samples showed dual HIV Ag&Ab reactivity and reactive NAT (HIV Ag&Ab++&HIV RNA R or NAT R), all confirmed as positive (100% infection rate); and 2 HIV Ag&Ab dual-reactive samples without NAT detection were also confirmed infected (100%). For all four HIV Ag&Ab assays, the S/CO values in the true positive group with dual reactivity were significantly higher than those in the false-positive groups (P<0.05). The S/CO distributions for both single-reactive false positives and dual-reactive false positives were narrow, with the upper box (Q3, 75th percentile) below optimal cutoff values in all cases (The optimal cutoff values for the four reagents were 5.00, 11.67, 8.50, and 20.90, respectively). Conclusion: Blood donors with positive NAT results in HIV blood screening are permanently deferred. Donors with dual positive HIV Ag&Ab but negative NAT results are classified and managed based on the S/CO values of HIV Ag&Ab and the optimal screening thresholds. Donors with single positive HIV Ag&Ab but negative NAT results are placed under evaluation status and retain their eligibility to donate blood. Optimizing the management measures for blood donors and establishing a scientific stratified management and assessment mechanism can effectively maintain the stability of the blood donor team.

Objective: To explore the management of blood donors tested reactive to HCV in blood screening based on confirmation of HCV infection. Methods: Multiple HCV antibody assays, repeating HCV RNA testing, follow-up of blood donors and retesting of archive samples were performed to confirm HCV infection, identify infection status, and exclude false positives in blood donors reactive to HCV in blood screening. Results: From 2011 to 2024, the unqualified rate of HCV detection in blood screening was 2.45‰(2 751/1 122 026). Among these, anti-HCV+-&NAT-accounted for 1.85‰, followed by anti-HCV++ at 0.60‰. The proportion of anti-HCV+-&NAT-and HCV RNA yields was extremely low (0.007‰). The positive rate of anti-HCV+-&NAT-samples tested by electrochemiluminescence method (ELCIA) was approximately 7.5%, differing among reagents (P<0.05). The follow-up of anti-HCV+-&NAT-donors showed that 96.2% (202/210) were false positives, but 51.4% of donors remained anti-HCV+-&NAT-during follow-up. Among them, 8 donors (3.8%) could not be ruled out from HCV infection due to positive retesting by ELCIA. Of the anti-HCV+-&NAT-donors who were reactive at the first follow-up, 86.8% remained anti-HCV+-&NAT-at the second follow-up. The sampling confirmation data showed that all of 260 anti-HCV++ donors were confirmed as anti-HCV positive, and the proportion of false positives or missed detections by NAT was very low. Two occult HBV infections (OBIs) and one HBsAg carrier were identified among the 3 anti-HCV +-&NAT+ donors, and no HCV infection was confirmed in 5 anti-HCV--&HCV RNA + donors. Conclusion: The prevalence of HCV among blood donors in Dalian was about 0.06%, with extremely low proportion of window-period infection and slightly higher proportion of resolved infections than that of current infections. The majority of anti-HCV+-&NAT-were false positive. Blood donors confirmed as false positive should be qualified in blood screening 3 months later before next donation. In order to reduce the false positive results, it was advisable to avoid the same type of supplementary reagents as the initial reagents when performing confirmation.

Objective: To systematically analyze the confirmatory positivity of different combinations of HBsAg screening results in blood testing, providing data to support the optimization of blood donor eligibility management. Methods: A retrospective analysis was conducted on blood screening data from 174 266 voluntary blood donor samples at the Chongqing Blood Center between October 2021 and September 2022. Samples with inconsistent results between the two HBsAg enzymelinked immunosorbent assays (ELISA) and individual donor nucleic acid testing (NAT) were confirmed using an electrochemiluminescence immunoassay (ECLIA) and a neutralization test. The detection efficacy of four different HBsAg ELISA reagents was compared using the HBsAg-confirmed positive samples. Results: A total of 767(0.44%) HBV-reactive (HB-sAg and/or HBV DNA reactive) samples were detected. Among them, 344 samples with discordant serological and NAT results were collected, of which 64(18.6%) were confirmed positive by neutralization test. Additionally, 5 samples that were neutralization-negative but double-reactive for HBsAg and HBV DNA were confirmed as positive according to FDA guidance, resulting in a total of 69(20.1%) confirmed HBsAg-positive samples. There were significant differences in the neutralization test confirmation rates among different screening result categories (P<0.05): The group with dual HBsAg reagent reactivity (double reactive) & NAT-negative had the highest confirmation rate (96.9%, 31/32); the group reactive to only reagent 2 (single reactive) had a rate of 25.7% (29/113); while the confirmation rates for samples reactive to only reagent 1 and samples with isolated HBV DNA positivity were extremely low [0(0/34) and 2.4%(4/165), respectively]. The four commercial reagents showed significant differences in their ability to detect confirmed positive samples that were initially single reactive (P<0.05). Conclusion: Given the performance variations among HBsAg screening reagents, thorough performance verification is essential before implementation. When NAT is negative, dual HBsAg reactivity in screening can serve as a basis for confirming infection and directly deferring blood donors. However, confirming infection in donors with single HBsAg reactivity is more challenging, necessitating supplementary tests to rule out infection risk.

Objective: To evaluate repeated testing on blood screening platforms in confirmation of non-discriminatory reactive (NDR) samples in nucleic acid testing (NAT). Methods: A total of 102 HBsAg-negative/NAT NDR samples were collected from voluntary blood donors at Dalian Blood Center between January 2021 and December 2023. Repeated testing was performed using two NAT platforms (Cobas s201 and Panther). For the first round of repeated testing, all samples were tested 12 times on each system; for the second round, the samples which were non-reactive or only reactive once in the first round were tested an additional 8 times. Anti-HBc and anti-HBs was detected using electrochemiluminescence assay (ECA). Meanwhile, blood donors were followed up. Results: The proportion of anti-HBc+ in 102 NDR samples was 88.2%. Forty-one samples (40.2%, 41/102) and 7 samples were confirmed HBV DNA+ in first-round and second-round repeated testing, respectively. The cumulative confirmation rate of HBV DNA+ was 47.1% (48/102) after repeated testing. Extra five blood donors detected HBV DNA+ in follow-up were identified as anti-HBc+ occult hepatitis B virus infection (OBI), while no window period infection was observed. Ultimately, there were 53 HBV infected donors confirmed, 46 HBV infection-unconfirmed, and 3 HBV uninfected. No significant difference was observed between the confirmation rate of the first-round testing and the cumulative confirmation rate after the second-round testing (P>0.05). The proportion of anti-HBc+ donors was quite high in both HBV infection-confirmed (98.1%) and unconfirmed group (82.6%), and donors with seronegative and anti-HBs-only occupied a high proportion in the latter (P<0.05). Conclusion: Numerous repeated testing of NDR samples using NAT platforms cannot achieve complete confirmation of HBV infection. Supplementary anti-HBc testing can minimize potential OBI risk among NDR donors, and is low-cost and efficient.

Objective: To investigate the regulatory role of miR-6824-3p in macrophage function and its molecular mechanism in inhibiting hepatitis B virus (HBV) replication, thereby providing experimental evidence to elucidate the immune regulatory mechanisms underlying persistent HBV infection. Methods: miR-6824-3p mimic and inhibitor were transfected into human THP-1-induced macrophages. Real-time quantitative PCR (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), neutral red uptake, reactive oxygen species (ROS) production, and fluorescent latex particle phagocytosis assays were employed to evaluate the effects of miR-6824-3p on macrophage phenotype and function. Through a combination of bioinformatics analysis, dual luciferase reporter assays, western blot, and siRNA interference techniques, we identified the target gene of miR-6824-3p and examined their effects on downstream signaling pathways. qRT-PCR and western blot analyses were performed to assess the impact of miR-6824-3p-regulated macrophages on HBV DNA, pgRNA, cccDNA, and HBV-associated antigen levels in HepAD38 cells. Key effector molecules were identified through neutralization assays. Results: miR-6824-3p mimic significantly promoted the expression and secretion of proinflammatory factors, such as TNF-α and IL-1β, in macrophages (P<0.001), while concurrently reducing ROS production and phagocytosis (P<0.05). Furthermore, miR-6824-3p downregulated NRAS expression in macrophages, which was accompanied by a reduction in MAPK signalling path-way activity (p-MEK, p-ERK). Compared to the control group, the medium of macrophages with overexpressed miR-6824-3p inhibited the expression of HBV DNA, pgRNA, cccDNA, and HBV-associated antigens HBsAg, HBeAg, and HBcAg in HepAD38 cells (P<0.01). Similar results were also observed in the co-culture system of macrophages with HepAD38 cells. The addition of TNF-α neutralizing antibodies markedly attenuated the aforementioned antiviral effects (P<0.001). Conclusion: miR-6824-3p targets NRAS to affect the downstream MAPK signaling pathway, regulating the immune function of macrophages. The TNF-α induced by miR-6824-3p is one of the key molecules that suppress HBV replication. This study provides evidence for further elucidating the molecular mechanisms by which miRNAs influence HBV replication via modulating the host immune microenvironment.

Objective: To verify the inhibitory effect of a carbon monoxide hemoglobin-based oxygen carrier (CO-HBOC) on the fibrotic process in mice with idiopathic pulmonary fibrosis (IPF), clarify its efficacy difference compared with hemoglobin-based oxygen carriers (HBOCs), and elucidate its mechanism of action via proteomic analysis. Methods: CO-HBOC was prepared using gas loading technology. An IPF mouse model was established and the mice were randomly divided into a normal saline control group, an HBOC treatment group, and a CO-HBOC treatment group. The fibrotic area percentage was analyzed using Micro-CT; the degree of inflammatory infiltration and fibrosis in lung tissue was assessed by pathological section staining (e.g., HE and Masson staining); and differentially expressed proteins in lung tissue of IPF mice after CO-HBOC treatment were screened using proteomic technology. Results: Micro-CT results showed that the mean fibrotic area percentage in the CO-HBOC treatment group on day 21 was (8.89±0.98)%, which was better than that of the HBOC group (16.5±1.732)% and the normal saline group (30.75±6.45)% (P<0.05). HE and Masson staining results showed that the CO-HBOC group had reduced inflammatory cell infiltration and significantly decreased collagen fiber deposition in lung tissue, with a mean pathological score of 3.33±0.58, which was lower than that of the normal saline control group (8.33±1.53)(P<0.05); the mean collagen-positive area percentage was (3.33±1.53)%, significantly lower than that of the normal saline control group (14.00±3.61)% (P<0.05). Proteomic analysis identified 330 differentially expressed proteins, which were mainly enriched in inflammatory response regulatory pathways (such as the complement and coagulation cascades), and the expression changes of complement proteins may be the core target of CO-HBOC's anti-fibrotic effects. Conclusion: CO-HBOC can inhibit inflammatory responses and regulate fibrosis-related signaling pathways, there-by effectively inhibiting the fibrotic process in IPF mice, with superior efficacy to HBOC. Its mechanism of action involves the regulation of complement cascade-related signaling pathways and complement protein expression, providing an experimental and theoretical basis for targeted therapy of IPF.

Objective: To enhance the ability of nanoparticles to target and bind tumor cells by constructing a neutrophil hitchhiking system based on hyaluronic acid (HA)-modified dual-drug loaded lipid nanoparticles. Methods: Lipid nanoparticles (LNPs) were prepared using microfluidic technology, and the nitrogen/phosphate (N/P) ratio, flow rate ratio, and drug-to-lipid ratio were optimized. HA-modified LNPs (HA-LNPs) were prepared and characterized. The interaction between the nanoparticles and tumor cells was evaluated through in vitro cell experiments. Results: The optimal preparation conditions for LNPs are N/P=8, flow rate ratio=5, and drug-to-lipid ratio=1∶30 (w∶w). HA-LNPs has a particle size of (177.28±2.41) nm, a polydispersity index (PDI) of 0.198±0.10, and an siRNA encapsulation efficiency of (91.37±0.47)%. The optimal binding rate with neutrophils was (98.64±2.34)%. Conclusion: An HA-modified dual-drug loaded lipid nanoparticle-neutrophil hitchhiking system was successfully constructed, enhancing the synergistic anti-tumor activity of the nanomedicine and the uptake of nanoparticles by tumor cells, providing a novel delivery strategy for targeted therapy of bone marrow tumors.