The apheresis platelet donation was increased after a nationwide ban on family/replacement donation in China.

BACKGROUND: A nationwide ban on family/replacement donation (FRD) went into effect on April 1, 2018 in China. To date, no reports relevant to the trend of plateletpheresis donations before and after a nationwide ban on FRD were found. METHODS: We used two independent full samples, consisting of 135,851 and 82,129 plateletpheresis donors from Guangzhou and Chengdu between October 2012 and September 2019, respectively. A pseudo-panel data approach was applied by grouping three time-invariant covariates - gender, blood donation history, and birth year across 14 cross-sections (a 6-month interval each) to form a total of 24 cohort groups (14 × 24 = 336 cohorts, i.e., cells) with each having common covariates. The outcome was average apheresis platelet units per donor in each cell. We performed a two-piecewise linear mixed model with the cross-section (i.e., time) just right before the ban as a time breakpoint (i.e., 11th cross-section) to examine the trend of outcome with the adjustment of three time-invariant covariates. We removed the FRDs in each of the first 11 cross-sections to detect its possible influence on the trend. RESULTS: The final model for the samples from Guangzhou presented a two-piecewise linear trend of the outcome over time with a horizontal line to the left of the breakpoint (ßtimeBefore11 = 0.0111, p = 0.0976) and a significantly positive linear trend to the right (ßtimeAfter11 = 0.0404, p < 0.0001). The male donors and the donors with plateletpheresis donation history had an increased baseline outcome and a significant outcome change over time after the ban. Such a two-piecewise linear trend pattern can be replicated using the samples from Chengdu with some minor variations. Removing the FRD before the ban can change the pattern. CONCLUSION: The significant increase of the average apheresis platelet units per donor over time after the FRD ban may be related to the implement of the FRD ban and the improved donation behavior of male donors and/or donors with platelet donation history after the ban. Our findings may potentially motivate the policymakers in other countries where the FRD for plateletpheresis donation is still legitimate to phase out their FRD strategy and ultimately achieve 100% voluntary plateletpheresis donation.

IL-Y, a synthetic member of the IL-12 cytokine family, suppresses the development of type 1 diabetes in NOD mice.

The IL-12 family of heterodimeric cytokines, consisting of IL-12, IL-23, IL-27, and IL-35, has important roles in regulating the immune response. IL-12 family members are comprised of a heterodimer consisting of α and ß chains: IL-12 (p40 and p35), IL-23 (p40 and p19), IL-27 (Ebi3 and p28), and IL-35 (Ebi3 and p35). Given the combinatorial nature of the IL-12 family, we generated adenoviral vectors expressing two putative IL-12 family members not yet found naturally, termed IL-X (Ebi3 and p19) and IL-Y (p40 and p28), as single-chain molecules. Single chain IL-Y (scIL-Y), but not scIL-X, was able to stimulate significantly a unique cytokine/chemokine expression profile as well as activate STAT3 in mice, in part, through a pathway involving IL-27Rα in splenocytes. Adenoviral-mediated, intratumoral delivery of scIL-Y increased tumor growth in contrast to the anti-tumor effects of scIL-12 and scIL-23. Similarly, treatment of prediabetic NOD mice by intravenous injection of Ad.scIL-Y prevented the onset of hyperglycemia. Analysis of cells from Ad.scIL-Y-treated NOD mice demonstrated that scIL-Y reduced expression of inflammatory mediators such as IFN-γ. Our data demonstrate that a novel, synthetic member of the IL-12 family, termed IL-Y, confers unique immunosuppressive effects in two different disease models and thus could have therapeutic applications.

Adeno-associated virus serotype 8 efficiently delivers genes to muscle and heart.

Systemic gene delivery into muscle has been a major challenge for muscular dystrophy gene therapy, with capillary blood vessels posing the principle barrier and limiting vector dissemination. Previous efforts to deliver genes into multiple muscles have relied on isolated vessel perfusion or pharmacological interventions to enforce broad vector distribution. We compared the efficiency of multiple adeno-associated virus (AAV) vectors after a single injection via intraperitoneal or intravenous routes without additional intervention. We show that AAV8 is the most efficient vector for crossing the blood vessel barrier to attain systemic gene transfer in both skeletal and cardiac muscles of mice and hamsters. Serotypes such as AAV1 and AAV6, which demonstrate robust infection in skeletal muscle cells, were less effective in crossing the blood vessel barrier. Gene expression persisted in muscle and heart, but diminished in tissues undergoing rapid cell division, such as neonatal liver. This technology should prove useful for muscle-directed systemic gene therapy.

Sustained whole-body functional rescue in congestive heart failure and muscular dystrophy hamsters by systemic gene transfer.

BACKGROUND: The success of muscular dystrophy gene therapy requires widespread and stable gene delivery with minimal invasiveness. Here, we investigated the therapeutic effect of systemic delivery of adeno-associated virus (AAV) vectors carrying human delta-sarcoglycan (delta-SG) gene in TO-2 hamsters, a congestive heart failure and muscular dystrophy model with a delta-SG gene mutation. METHODS AND RESULTS: A single injection of double-stranded AAV serotype 8 vector carrying human delta-SG gene without the need of any physical or pharmaceutical interventions achieved nearly complete gene transfer and tissue-specific expression in the heart and skeletal muscles of the diseased hamsters. Broad and sustained (>12 months) restoration of the missing delta-SG gene in the TO-2 hamsters corrected muscle cell membrane leakiness throughout the body and normalized serum creatine kinase levels (a 50- to 100-fold drop). Histological examination revealed minimal or the absence of central nucleation, fibrosis, and calcification in the skeletal muscle and heart. Whole-body functional analysis such as treadmill running showed dramatic improvement, similar to the wild-type F1B hamsters. Furthermore, cardiac functional studies with echocardiography revealed significantly increased percent fractional shortening and decreased left ventricular end-diastolic and end-systolic dimensions in the treated TO-2 hamsters. The survival time of the animals was also dramatically extended. CONCLUSIONS: Systemic gene transfer of delta-SG by the AAV serotype 8 vector could effectively ameliorate cardiac and skeletal muscle pathology, profoundly improve cardiac and whole-body functions, and significantly prolong the lifespan of the treated TO-2 hamsters.

Adeno-associated virus vector-mediated minidystrophin gene therapy improves dystrophic muscle contractile function in mdx mice.

Duchenne muscular dystrophy (DMD) is the most common disabling and lethal genetic muscle disorder, afflicting 1 of every 3500 males. Patients with DMD experience progressive muscle degeneration and weakness and succumb to respiratory or cardiac failure by their early twenties. No treatment is currently available for DMD. Mutations in the dystrophin gene result in lack of a functional dystrophin protein in striated muscle, which induces instability in the muscle cell membrane leading to persistent muscle injury after contraction. We have previously created novel minidystrophin genes and demonstrated that adeno-associated virus (AAV)-mediated intramuscular delivery of the minigenes effectively ameliorated mdx dystrophic histopathology and led to normal cell membrane integrity for more than 1 year. In this paper, we investigated whether AAV-minidystrophin could also improve mdx muscle contractile function. Two-month-old adult male mdx mice, with established muscular dystrophy, were given a single-dose injection of an AAV-minidystrophin vector in the tibialis anterior (TA) muscle of one leg, with the untreated contralateral leg used as a control. The treated TA muscle showed both (1) a significant increase in isometric force generation and (2) a significant increase in resistance to lengthening activation-induced muscle force decrements. We conclude that AAV-minidystrophin gene treatment is effective in improving mdx muscle contractile function.

c-FLIP-L recombinant adeno-associated virus vector infection prevents Fas-mediated but not nerve growth factor withdrawal-mediated cell death in PC12 cells.

Fas is a cell surface death receptor that may play an important role in regulating cell death in neuronal cell types by activation of caspase 8. Cellular FLICE inhibitory protein-long (c-FLIP-L) is an endogenous inhibitor of the activation of caspase 8 by Fas. The current study addresses the role of c-FLIP-L in regulation of cell death in PC12 cells induced by nerve growth factor (NGF) withdrawal and Fas antibody, which acts as a Fas ligand and activates the Fas receptor. A recombinant adeno-associated virus (rAAV) vector that expresses c-FLIP-L was constructed. PC12 cells infected with the c-FLIP-L rAAV were resistant to apoptosis induced by treatment with Fas antibody compared to cells infected with enhanced green fluorescent protein (EGFP) expressing rAAV. Overexpression of c-FLIP-L rAAV inhibited cleavage of caspase 8 induced by Fas antibody treatment. In contrast, treatment with the c-FLIP-L rAAV did not protect PC12 cells from cell death induced by NGF withdrawal. In conclusion, overexpression of c-FLIP-L rAAV inhibits Fas antibody-mediated cell death, but not NGF withdrawal-mediated cell death in PC12 cells.

Long-term protection against human papillomavirus e7-positive tumor by a single vaccination of adeno-associated virus vectors encoding a fusion protein of inactivated e7 of human papillomavirus 16/18 and heat shock protein 70.

We investigated a gene vaccine strategy against human papillomavirus (HPV)-induced cancer and premalignant diseases, using adeno-associated virus (AAV) vector encoding the viral E7 oncoproteins as the tumor antigens from HPV serotypes 16 (HPV16) and 18 (HPV18). Genetically inactivated E7 proteins were fused with a heat shock protein 70 (hsp70) to minimize the risk of cell transformation and enhance immune responses. The fusion protein gene was packaged in AAV serotype 1 or 2 (AAV1 or 2) for efficient in vivo gene expression. Our results showed that after a single intramuscular injection, the AAV1 vector elicited stronger HPV-specific cytotoxic T lymphocyte (CTL) responses and interferon-gamma secretion when compared with the AAV2 vector. Prophylactic immunization with AAV1 protected 100% of the mice from tumor growth for more than 1 year, whereas all the control mice immunized with either a LacZ vector or saline grew large tumors and died within 6 weeks after inoculation of E7-positive tumor cell line TC-1. In addition, this single-dose AAV1 vaccination completely protected the mice against second and third challenges with higher numbers of TC-1 cells. Despite lower CTL responses against the E7 antigens, AAV2 vector prophylactic immunization was also sufficient to protect 100% of the mice against the initial and second tumor challenges and 70% of the mice against the third challenge. In addition, therapeutic immunization with AAV1 after palpable tumor formation inhibited tumor growth and caused tumor regression in some mice. Thus, our studies support the potential of AAV vectors as a genetic vaccine for the prevention and treatment of HPV-induced malignancies.