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 analyze the changing trend and distribution characteristics of hepatitis C virus (HCV) infection among blood donors in Hebei, thereby providing data to support strategy and procedure adjustment for blood collection and supply institutions. Methods: Data from 12 blood stations in Hebei Province from 2012 to 2021 were collected. These data were analyzed to determine trends in anti-HCV antibody double reagent reactive rate and to characterize its distribution among different donor categories, genders and birth cohorts. Results: During the period from 2012 to 2021, a total of 7.4576 million samples were tested at 12 blood stations in Hebei Province, with 3.4659 million (46.47%) from first-time donors, and 3.9917 million (53.53%) from repeat donors. The number (of anti-HCV double reagent reactive samples was 7167 (9.61/10 000). The anti-HCV double reagent reactive rate showed a annual downward trend (P<0.05), from 17.40/10 000 at the beginning to 4.95/10 000 at the end of the study period. Additionally, the double reagent reactive rate of repeat blood donors had remained below 1/10 000 since 2017. The double reagent reactive rate of first-time blood donors (19.42/10 000) was higher than in repeat donors (1.09/10 000) (P<0.05), and the double-reagent reactive rate of female first-time blood donors (20.98/10 000) was higher than that of male first-time blood donors (18.49/10 000) (P<0.05). The anti-HCV double reagent reactive rate among first-time donors exhibited two distinct peaks within the pre-1976 and 1989-1994 birth cohorts, with notable gender differences observed in both peak periods. The rate of double reagent reactive in females born before 1976 (52.22/10 000) was higher than that in males (32.28/10 000) (P<0.05), while that of males born in 1989-1994 was higher (25.75/10 000) than that of females (14.28/10 000) (P<0.05). Conclusion: The prevalenc of HCV infection among blood donors in Hebei Province has shown a consistent year-over-year decline over the study period. The majority of infected individuals are found among the first-time blood donors born before 1995. These trends and characteristics provide valuable insights for developing pre-blood collection screening strategies, analyzing nucleic acid test data in blood screening, adjusting blood screening procedures, and provide evidence for targeted screening of high-risk populations as part of public health initiatives to eliminate hepatitis C.

【Objective】 To study the characteristics of HIV infection among voluntary blood donors in Shijiazhuang from 2011 to 2021, so as to provide reference for decision making in the control of HIV for blood centers. 【Methods】 The confirmatory results of HIV reactive samples in initial screening among voluntary blood donors from 2011 to 2021 in our center were statistical analyzed. 【Results】 A total of 2 008 299 samples from 1 667 315 blood donors were detected, among which 3 217 samples were HIV reactive and 234 were confirmed positive, with the positive rate at 11.65/100 000 and the prevalence of 14.03/100 000. The prevalence in men was higher than that in women (16.52/100 000 vs 1.39/100 000), in first-time blood donors higher than that in repeated donors (17.27/100 000 vs 8.12/100 000), in whole blood donors higher than that in plateletpheresis donors (12.01/100 000 vs 8.41/100 000), and the differences were statistically significant (P<0.05). The male homosexual transmission was the main routes of transmission, accounting for 62.39% (146/234). And 72% of double-reagent reactive samples were confirmed positive. Four samples were screened in the serological window period and 6 samples were from HIV positive confirmed donors. 【Conclusion】 The HIV prevalence among voluntary blood donors in Shijiazhuang was low. A certain percentage of repeated blood donors got newly infected. NAT could shorten the detection window period of HIV. Since some confirmed positive samples had not been detected out by NAT, publicity and education should be strengthened to reduce the probability of infected or high-risk groups to participate in blood donation.

Tolerogenic dendritic cells (tolDCs) facilitate the suppression of autoimmune responses by differentiating regulatory T cells (Treg). The dysfunction of immunotolerance results in the development of autoimmune diseases, such as rheumatoid arthritis (RA). As multipotent progenitor cells, mesenchymal stem cells (MSCs), can regulate dendritic cells (DCs) to restore their immunosuppressive function and prevent disease development. However, the underlying mechanisms of MSCs in regulating DCs still need to be better defined. Simultaneously, the delivery system for MSCs also influences their function. Herein, MSCs are encapsulated in alginate hydrogel to improve cell survival and retention in situ, maximizing efficacy in vivo. The three-dimensional co-culture of encapsulated MSCs with DCs demonstrates that MSCs can inhibit the maturation of DCs and the secretion of pro-inflammatory cytokines. In the collagen-induced arthritis (CIA) mice model, alginate hydrogel encapsulated MSCs induce a significantly higher expression of CD39⁺CD73⁺ on MSCs. These enzymes hydrolyze ATP to adenosine and activate A_2A/2B receptors on immature DCs, further promoting the phenotypic transformation of DCs to tolDCs and regulating naïve T cells to Tregs. Therefore, encapsulated MSCs obviously alleviate the inflammatory response and prevent CIA progression. This finding clarifies the mechanism of MSCs-DCs crosstalk in eliciting the immunosuppression effect and provides insights into hydrogel-promoted stem cell therapy for autoimmune diseases.

Monocytes are key effectors in autoimmunity-related diseases in the central nervous system (CNS) due to the critical roles of these cells in the production of proinflammatory cytokines, differentiation of T-helper (Th) cells, and antigen presentation. The JAK-STAT signaling is crucial for initiating monocytes induced immune responses by relaying cytokines signaling. However, the role of this pathway in modulating the communication between monocytes and Th cells in the pathogenesis of multiple sclerosis (MS) is unclear. Here, we show that the JAK1/2/3 and STAT1/3/5/6 subtypes involved in the demyelination mediated by the differentiation of pathological Th1 and Th17 and the CNS-infiltrating inflammatory monocytes in experimental autoimmune encephalomyelitis (EAE), a model for MS. JAK inhibition prevented the CNS-infiltrating CCR2-dependent Ly6C^hi monocytes and monocyte-derived dendritic cells in EAE mice. In parallel, the proportion of GM-CSF⁺CD4⁺ T cells and GM-CSF secretion were decreased in pathological Th17 cells by JAK inhibition, which in turns converted CNS-invading monocytes into antigen-presenting cells to mediate tissue damage. Together, our data highlight the therapeutic potential of JAK inhibition in treating EAE by blocking the GM-CSF-driven inflammatory signature of monocytes.