Interface-constrained catalytic hairpin assembly permits highly sensitive SERS signaling of miRNA.

The rapid and precise monitoring of peripheral blood miRNA levels holds paramount importance for disease diagnosis and treatment monitoring. In this study, we propose an innovative research strategy that combines the catalytic hairpin assembly reaction with SERS signal congregation and enhancement. This combination can significantly enhance the stability of SERS detection, enabling stable and efficient detection of miRNA. Specifically, our paper-based SERS detection platform incorporates a streptavidin-modified substrate, biotin-labeled catalytic hairpin assembly reaction probes, 4-ATP, and primer-co-modified gold nanoparticles. In the presence of miRNA, the 4-ATP and primer-co-modified gold nanoparticles can specifically recognize the miRNA and interact with the biotin-labeled CHA probes to initiate an interfacial catalytic hairpin assembly reaction. This enzyme-free high-efficiency catalytic process can accumulate a large amount of biotin on the gold nanoparticles, which then bind to the streptavidin on the substrate with the assistance of the driving liquid, forming red gold nanoparticle stripes. These provide a multitude of hotspots for SERS, enabling enhanced signal detection. This innovative design achieves a low detection limit of 3.47 fM while maintaining excellent stability and repeatability. This conceptually innovative detection platform offers new technological possibilities and solutions for clinical miRNA detection.

Evaluation of Lens Culinaris Agglutinin-Reactive α-Fetoprotein in Diagnosis of Malignant Tumors.

BACKGROUND: To assess the potential of AFP-L3% for the utility to diagnose malignant tumors. METHODS: AFP-L3 was concentrated from clinically-collected serum samples via the Hotgen Biotech glycosyl capture spin columns and then measured through the protein microarrays. The levels of AFP and AFP-L3 were detected by electrochemiluminescence immunoassay. In this retrospective study, 266 patients with the level of serum AFP-L3 over 1 ng/mL were recruited from December 2014 through April 2019. Among them, 155 patients were clinically diagnosed/confirmed with malignant tumors, including 101 hepatocellular carcinomas, 47 stomach malignant tumors, and 7 other malignant tumors; and the rest of 111 patients were nonmalignant tumors. RESULTS: Patients with serum AFP-L3 level of greater than 1 ng/mL were mainly detected in hepatic diseases, including hepatocellular carcinoma, cirrhosis and chronic hepatitis. In patients with no tumors, the levels of serum AFP-L3 over 1 ng/mL were only observed in liver disease. The levels of AFP-L3 in blood were substantially greater in patients with HCC. Among the malignant tumor patients with the level of serum AFP-L3 over 1 ng/mL, HCC accounted for 60%, gastric cancer for nearly 40%. The AFP, AFP-L3, and AFP-L3% in blood were increased significantly in patients with liver malignancy, chronic liver disease, and cirrhosis. However, the elevation of AFP-L3 and AFP-L3% in the malignant cohort was more evident than that in the nonmalignant counterpart. CONCLUSIONS: AFP-L3 is likely to contribute to the differential diagnosis of HCC as well as other hepatic diseases. AFP-L3% is a reliable indicator for diagnosing benign and malignant tumors.

A Case Report of Serological Rapid Diagnostic Test-Negative Plasmodium malariae Malaria Imported from West Africa.

BACKGROUND: The imported cases of Plasmodium malariae (P. malariae) and Plasmodium ovale (P. ovale) malaria are increasing annually, especially in central China. Here, we report a case of serological rapid diagnostic test (RDT)-negative P. malariae malaria imported from West Africa. METHODS: The case patient was exclusively diagnosed with P. malariae through microscopy, Plasmodium genus-specific nested polymerase chain reaction (PCR), and sequencing of targeted P. malariae circumsporozoite (pmcsp) gene, except for serological RDT. RESULTS: The patient was discharged in stable condition after 5 days of hospitalization, with no overt malaria parasites or associated symptoms. CONCLUSIONS: This case reveals that asymptomatic P. malariae infections can occur among exported laborers back from malaria-endemic areas, some of whom may escape serological screening test or RDT, posing a continuing potential threat to malaria control. Therefore, PCR-based molecular techniques are more effective and necessary than serological RDT for malaria surveillance nationwide.

Type 1 diabetes induction in humanized mice.

There is an urgent and unmet need for humanized in vivo models of type 1 diabetes to study immunopathogenesis and immunotherapy, and in particular antigen-specific therapy. Transfer of patient blood lymphocytes to immunodeficient mice is associated with xenogeneic graft-versus-host reactivity that complicates assessment of autoimmunity. Improved models could identify which human T cells initiate and participate in beta-cell destruction and help define critical target islet autoantigens. We used humanized mice (hu-mice) containing robust human immune repertoires lacking xenogeneic graft-versus-host reactivity to address this question. Hu-mice constructed by transplantation of HLA-DQ8+ human fetal thymus and CD34+ cells into HLA-DQ8-transgenic immunodeficient mice developed hyperglycemia and diabetes after transfer of autologous HLA-DQ8/insulin-B:9-23 (InsB:9-23)-specific T-cell receptor (TCR)-expressing human CD4+ T cells and immunization with InsB:9-23. Survival of the infused human T cells depended on the preexisting autologous human immune system, and pancreatic infiltration by human CD3+ T cells and insulitis were observed in the diabetic hu-mice, provided their islets were stressed by streptozotocin. This study fits Koch's postulate for pathogenicity, demonstrating a pathogenic role of islet autoreactive CD4+ T-cell responses in type 1 diabetes induction in humans, underscores the role of the target beta-cells in their immunological fate, and demonstrates the capacity to initiate disease with T cells, recognizing the InsB:9-23 epitope in the presence of islet inflammation. This preclinical model has the potential to be used in studies of the pathogenesis of type 1 diabetes and for testing of clinically relevant therapeutic interventions.

CXCR4 blockade improves leukemia eradication by allogeneic lymphocyte infusion.

Persistent low levels of disease in bone marrow, an immunoprivileged tissue, are responsible for relapse following allogeneic hematopoietic cell transplantation. Using mouse models carrying primary human acute lymphoblast leukemia derived from MLL-AF9-overexpressing human hematopoietic stem cells, we demonstrate that allogeneic lymphocyte infusion (ALI)-mediated graft-vs.-leukemia effects selectively spare leukemia cells in the bone marrow. The resistance of leukemia cells to ALI within bone marrow is due to the immunosuppressive status of the tissue, as ALI achieved a significantly increased complete remission rate when leukemia cells were dislodged from bone marrow by treatment with a CXCR4 antagonist AMD3100. Adoptive transfer experiments confirmed that the frequency of leukemia-initiating cells in bone marrow was significantly decreased in the recipients treated with ALI plus AMD3100 compared to those receiving ALI only. These findings indicate that the immunoprivileged nature of bone marrow is largely responsible for relapse after immunotherapies, and that treatment with AMD3100 may offer a clinically-practical approach to improving the outcome of adoptive allogeneic cell therapy.

Tumor Acidity-Sensitive Polymeric Vector for Active Targeted siRNA Delivery.

Although surface PEGylation of siRNA vectors is effective for preventing protein adsorption and thereby helps these vectors to evade the reticuloendothelial system (RES) in vivo, it also suppresses the cellular uptake of these vectors by target cells. This dilemma could be overcome by employing stimuli-responsive shell-detachable nanovectors to achieve enhanced cellular internalization while maintaining prolonged blood circulation. Among the possible stimuli, dysregulated pH in tumor (pHe) is the most universal and practical. However, the design of pHe-sensitive system is problematic because of the subtle differences between the pHe and pH in other tissues. Here, a simple acid-sensitive bridged copolymer is developed and used for tumor-targeted systemic delivery of siRNA. After forming the micelleplex delivery system, the corresponding nanoparticles (Dm-NP) might undergo several modifications as follows: (i) a poly(ethylene glycol) (PEG) corona, which is stable in the circulatory system and protects nanovectors from RES clearance; (ii) a pHe responsive linkage breakage, which induces PEG detachment at tumor sites and thereby facilitates cell targeting; and (iii) a cell-penetration peptide, which is exposed upon the removal of PEG and further enhances cellular uptake. Thus, Dm-NP achieved both prolonged circulation and effective accumulation in tumor cells and resulted in the safe and enhanced inhibition of non-small cell lung cancer growth.

Urine immunofixation electrophoresis and serum free light chain analyses benefit diagnosis of multiple myeloma in orthopedic patients with normal serum total proteins, creatinine, calcium, and hemoglobin.

BACKGROUND: A substantial number of patients with multiple myeloma (MM) who have bone destruction are initially admitted into the orthopedic service at the hospital. However, routine laboratory testing usually fails to identify these patients, thus delaying optimal therapy. Therefore, there is a clear medical need for early diagnosis of MM in these patients. METHODS: Between 2019 and 2021, 42 patients receiving treatment for orthopedic conditions had normal hemoglobin (Hb), total protein (TP), albumin (ALB), creatinine (CREA), and blood calcium (Ca) levels before their surgical procedure(s) but were subsequently pathologically confirmed to have MM, based on their presenting orthopedic symptoms. During the same period, 52 patients with orthopedic conditions were pathologically excluded from the diagnosis of MM and were recruited into our control group. Serum free light chain (sFLC) testing was performed in 94 consecutive patients in the orthopedic service using Siemens N Latex FLC kits. The levels of Hb, TP, ALB, CREA, and Ca were also measured. All 42 patients with MM were divided into group A (n = 25: κ proliferation) and group B (n = 17: λ proliferation) by the pathology department. RESULTS: There were no significant differences in levels of Hb, TP, ALB, CREA, and Ca between group A and group B and the control group. However, the sFLC κ/λ ratio of group A and B was also significantly different from that of the control group (P < .001). The results of serum immunofixation electrophoresis (IFE) testing demonstrated negative results in 14 cases (58.3%) in group A and 4 cases (25.0%) in group B. CONCLUSIONS: Some patients with orthopedic conditions who do not have typical MM laboratory results, such as those with abnormal Hb, TP, ALB, CREA, and Ca levels before their operation(s), actually have MM. MM should be highly suspected in patients with unexplained bone lesions and with an abnormal sFLC κ/λ ratio. Further tissue or bone marrow biopsy is needed in these patients even if serum and urine IFE results are negative and light chain ratio is normal.

Immunogenic and diagnostic potential of recombinant apical membrane antigen-1 from Plasmodium malariae.

The apical membrane antigen-1 (AMA-1) is a crucial target for malaria management and prevention strategies. While the immunogenicity of AMA-1 has been extensively studied for Plasmodium falciparum and Plasmodium vivax, there is a notable scarcity of information for Plasmodium malariae. In this study, recombinant PmAMA-1 was expressed in Escherichia coli, and its integrity was confirmed via western blotting and indirect immunofluorescence assays. Immunization of BALB/c mice with rPmAMA-1 emulsified in Freund's adjuvant resulted in significantly elevated specific IgG antibodies, predominantly IgG1. The immune response exhibited Th1, Th2, and Th17 phenotypes, with a notable Th1 bias. Antisera from immunized mice effectively recognized native PmAMA-1 on P. malariae. These results suggest that PmAMA-1 is a promising target for both vaccine development and diagnostic applications for P. malariae infections, offering dual preventive and diagnostic benefits in malaria control.

Epidemiological and Antimicrobial Resistant Patterns, and Molecular Mechanisms of Carbapenem-Resistant Klebsiella pneumoniae Infections in ICU Patients.

Objective: To study the epidemiological and antimicrobial resistant patterns, clinical characteristics and risk factors of critically ill patients infected with carbapenem-resistant Klebsiella pneumoniae (CRKP) from intensive care units (ICUs). The potential molecular mechanisms of antimicrobial resistance and virulence of CRKP were investigated through evaluation of associated genes. Methods: Totally, 201 ICU patients infected with K. pneumoniae were recruited from January 2020 through January 2021. K. pneumoniae strains were collected from diverse clinical specimens and identified by microbial cultures and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. Antimicrobial resistance was measured through broth micro-dilution or Kirby-Bauer assays. The carbapenemase-, virulence-, and capsular serotype-associated genes of CRKP were individually detected by PCR and sequencing. Demographic and clinical profiles were acquired from hospital databases to evaluate the correlation of CRKP infection incidence with clinical risk factors. Results: Of the 201 K. pneumoniae strains, CRKP accounted for 41.29%. Seasonal bias existed in local prevalence of CRKP infections. CRKP strains mounted significantly strong resistance against major antimicrobial agents except ceftazidime-avibactam, tigecycline and minocycline. Recent exposure to certain antibiotics and prior treatment with invasive interventions were prone to increase CRKP infection risks with worsened infectious outcomes. The local top carbapenemase-encoding and virulence-associated genes of CRKP were blaKPC and irp2, respectively. Nearly half of CRKP isolates harbored a capsular polysaccharide serotype of K14.K64 (wzi-64) which preferentially emerged in the cohort with worse outcomes of infection. Conclusion: Featured epidemiology and typical clinical characteristics existed extensively in K. pneumoniae infections among ICU patients. The CRKP cohort exhibited substantially high antimicrobial resistance. Distinctive carbapenemase-, virulence-, and serotype-associated genes were intensively involved in the spread and pathogenesis of CRKP. These findings supported careful management of critically ill patients potentially infected with virulent CRKP in the ICUs.

Methodological comparison of bronchoalveolar lavage fluid-based detection of respiratory pathogens in diagnosis of bacterium/fungus-associated pneumonia in critically ill patients.

Background: Bacterium/fungus-associated pneumonia (BAP/FAP) is the prominent cause of high mortality and morbidity with important clinical impacts globally. Effective diagnostic methods and proper specimen types hopefully facilitate early diagnosis of pneumonia and prevent spread of drug-resistant bacteria/fungi among critically ill patients. Methods: In the present study, 342 bronchoalveolar lavage fluid (BALF) samples were collected from critically ill patients with pulmonary infections between November 2020 and March 2021. The BALF materials were comparatively employed to screen BAP/FAP through microscopy, culture, antigenic marker and PCR-based methods. The limit of detection (LOD) of cultures and PCR for bacteria/fungi was determined by serial dilution assays. Specimen slides were prepared with Gram staining for microscopic examinations. Microbial cultures and identifications underwent routine clinical protocols with the aid of mass spectrometry. (1,3)-ß-D-glucan and galactomannan tests with BALF were carried out accordingly. Direct detection of pathogens in BALF was achieved through PCR, followed by sequencing and BLAST in GenBank database for pathogenic identification. The subjects' demographic and clinical characteristics were well evaluated. Results: BAP/FAP was identified in approximately 47% of the subjects by the BALF-based PCR. The PCR-based diagnostic methods showed improved detection performance for fungi with good LOD, but performed similarly for bacteria, when compared to the cultures. There was poor agreement among traditional microscopy, culture and PCR assays for bacterial detections (kappa value, 0.184 to 0.277). For overall bacterial/fungal detections, the microscopy showed the lowest detecting rate, followed by the cultures, which displayed a slightly higher sensitivity than the microscopy did. The sensitivity of PCR was much higher than that of the other means of interest. However, the traditional cultures rather than antigenic marker-based approaches were moderately consistent with the PCR-based methods in fungal species identification, particularly for Candida and Aspergillus spp. Our findings further revealed that the age, length of hospital stay, invasive procedures and cerebral diseases were likely considered as main risk factors for BAP/FAP. Conclusion: Screening for BALF in critically ill patients with suspected pneumonia pertaining high risk factors using combined PCR-based molecular detection strategies would hopefully contribute to early diagnosis of BAP/FAP and improved prognosis of the patients.

Comparative Analysis of Epidemiological and Clinical Characteristics Between Invasive Candida Infection versus Colonization in Critically Ill Patients in a Tertiary Hospital in Anhui, China.

Objective: Invasive infections due to Candida spp. have unique epidemiology, strain distribution, antimicrobial susceptibility, and clinical features. This study aimed to compare and evaluate these characteristic variables between invasive Candida infection and colonization of critically ill patients in local China to potentially improve differential diagnosis and therapy. Methods: A total of 193 critically ill patients were recruited and followed up for the study, and 133 Candida isolates were obtained from invasive Candida-infected or -colonized subjects. The strains were identified to species level through matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry, assisted by DNA sequencing. Candida susceptibility to common antifungals, including azoles, was determined by microbroth ATB Fungus 3 methodology. Azole resistance-related gene sequencing and homologous 3D-structure modeling were employed. Patient demographics and clinical risk factors were documented and comparatively analyzed from the hospital information-management system. Results: Non-C. albicans Candida (56%) principally caused invasive Candida infections, while C. albicans (55.17%) contributed more to Candida colonization in critically ill patients. Additional risk factors exerted significant impact on both Candida cohorts, primarily including invasive interventions, cancers, and concurrent infections in common. Most colonized Candida spp. harbored relatively higher sensitivity to azoles. ERG11 gene mutations of T348A and A1309G, A395T and C461T, and a novel G1193T to our knowledge were identified in azole-resistant C. albicans, C. tropicalis, and C. parapsilosis respectively, and their corresponding homologous 3D-structure modeling was putatively achieved. Conclusion: Distinct epidemiological and clinical characteristics existed between invasive Candida infection and colonization in critically ill patients. Multiple risk factors significantly involved both the Candida cohorts. Colonized Candida exhibited generally higher azole sensitivity than invasively infectious counterparts. ERG11 point mutations had mechanistically potential ties with local Candida resistance to azoles.

Immunosuppressed Patients with Clinically Diagnosed Invasive Fungal Infections: The Fungal Species Distribution, Antifungal Sensitivity and Associated Risk Factors in a Tertiary Hospital of Anhui Province.

OBJECTIVE: Since the nosocomial fungal infections increasingly emerge, we extensively investigated the fungal species stratification and antifungal sensitivity profiles, clinical characteristics and associated risk factors of immunosuppressed patients with clinically diagnosed invasive fungal infections (IFIs) in a tertiary hospital of Anhui province. METHODS: In total, 112 subjects with immunosuppressive state were enrolled from a comprehensive tertiary hospital in Central China between July 2019 and December 2021. Eight-one fungal isolates were clinically recovered by fungus-culturing approaches. The identifications were conducted through a mass spectrometry detecting platform. The susceptibilities to antifungals were tested using the broth micro-dilution method, and the possible antifungal azole-resistance mechanism in specific Candida species was availably explored by sequencing. Patient medical profiles were accessed via the digitized retrieval system of hospital, from which clinical outcomes and multiple risk factors for immunosuppressed patients with clinically diagnosed IFIs were explicitly documented for evaluation. RESULTS: Candida species predominated in clinically diagnosed IFIs of immunosuppressed patients (accounting for 88.88%), followed by Trichosporon and Aspergillus species (6.17% and 4.94%, respectively). The source types of specimen were primarily comprised of urine (41.98%), respiratory samples (33.33%) and peripheral blood (9.88%). Frequently isolated Candida and Trichosporon species exhibited a high level of in vitro sensitivity for amphotericin B and 5-fluorocytosine, whereas a substantial portion of Candida species including C. glabrata, C. parapsilosis complex and C. tropicalis, and Trichosporon species showed lowered sensitivity patterns toward itraconazole, fluconazole and voriconazole at different levels. Specifically, gene mutations of ERG11 were identified in azole-resistant C. tropicalis. Distinct risk factors were analyzed to be highly associated with the clinically diagnosed IFI incidence, mainly including hospitalization duration, surgical procedures, immunosuppressive treatments, underlying diseases and other conditions. CONCLUSION: Candida, Trichosporon and Aspergillus species were the top three pathogenic fungal agents causing clinically diagnosed IFIs in immunosuppressed patients. The attenuated sensitivity to azoles in Candida and Trichosporon species needs close surveillance, and ERG11 polymorphism might contribute to azole resistance in specific Candida species. Multiple featured risk factors for immunosuppressed patients developing clinically diagnosed IFIs require further consideration during clinical practice.

[Full-zirconia single-tooth molar implant-supported restorations with angulated screw channel abutments: evaluation of short-term outcomes].

PURPOSE: To evaluate the effect of full-zirconia single-tooth molar implant-supported restorations with angulated screw channel abutments. METHODS: Seventy-six patients with a single missing tooth in the posterior region of the maxilla and mandible underwent dental implants from March 2016 to March 2018 were enrolled. After 3 months, each patient received a full-contour screw-retained zirconia restoration with angulated screw channel abutment. Modified sulcus bleeding index (MSBI), modified plaque index (mPLI), periodontal probing depth (PD), marginal bone levels (MBLs) and mid-buccal mucosal levels (MBMLs) were recorded at the implantation moment (T0), four weeks (T1), one year (T2) and two years (T3) after treatment. During the follow-up period, the incidence of implant defects, survival rate and porcelain fracture were recorded. The data were processed using SPSS 23.0 software package. RESULTS: Of the 76 patients, 9 did not have a complete follow-up record (two of the implants failed before restoration, two patients had bilateral first molars missing, and five were lost to follow-up), and the remaining 67 patients with a total of 67 implants had a complete follow-up record. The success rate of implant was 97.01%(65/67) during one-year follow-up, and the initial success rate was 100% at an interval of three months. Compared with indexes at T0, mSBI and mPLI were significantly reduced at T1, T2 and T3 (P<0.05). There was no significant difference in PD level at T0, T1, T2 and T3(P>0.05), and the effective depth averaged 1.75 mm. Compared with indexes at T0, MBLs and MBMLs were significantly increased at T1(P<0.05). A total of 4 cases had implant reconstruction at T1 due to concerns about framework fracture, veneering fracture and aesthetics. At T2 and T3, there was no implant problems and loosening of restoration. There were 2 cases of peri-implant inflammation, one case of implant loss and one case of abutment pain, which were all improved after corresponding treatments. Two cases of porcelain fracture occurred in 67 zirconia restorations (2.63%), and the implant survival rate was 100%. CONCLUSIONS: Full-zirconia single-tooth molar implant-supported restorations with angulated screw channel abutments can effectively improve the implant stability in early phase, with high success rate, good short-term effect and few complications.

Candida Isolates From Blood and Other Normally Sterile Foci From ICU Patients: Determination of Epidemiology, Antifungal Susceptibility Profile and Evaluation of Associated Risk Factors.

Background: The clinical diagnosis and therapy for ICU patients with invasive candidiasis are challenged by the changes of Candida community composition and antimicrobial resistance. The epidemiology and drug sensitivity of candidiasis in ICU as well as its risk factors and drug resistance mechanism were investigated. Methods: In the present study, 115 patients in ICU were recruited from June 2019 through July 2020. Among them, 83 Candida isolates were identified with MALDI-TOF mass spectrometry. The susceptibility to antifungals was measured by microdilution method. The molecular mechanisms of azole-resistant Candida tropicalis were explored by sequencing, and their outcomes were explicitly documented. Results:Candida glabrata and C. tropicalis were the predominant non-C. albicans Candida. The specimen sources were mainly urine, bronchoalveolar lavage fluid and blood. The age, length of hospitalization, tracheotomy, diabetes and concomitant bacterial infection were the main risk factors for candidiasis. The majority of Candida species exhibited susceptibility to antifungals. However, certain C. tropicalis were frequently resistant to azoles. The polymorphism of the ERG11 in C. tropicalis was likely associated with azole resistance. Conclusion: The multiple risk factors for candidiasis in ICU patients need to be considered. Certain C. tropicalis exhibit resistance to azoles likely due to the ERG11 gene polymorphism.

Auxiliary diagnosis of Lung Cancer on the basis of a Serum Protein Biomarker Panel.

Objectives: In this study, we established a serum protein biomarker panel (consisting of Pro-SFTPB, CA125, Cyfra21-1, and CEA) and evaluated the feasibility and performance for the auxiliary diagnosis of lung cancer in the Chinese population. Materials and Methods: The current study was a single-center study based on the Chinese population and performed in two cohorts (training cohort and validation cohort). Serum concentrations of Pro-SFTPB, CA125, Cyfra21-1, and CEA were measured by a bead-based flow fluorescence immunoassay. The discrimination performance of the model was assessed using sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve (AUC). Results: For the biomarker panel model, the AUC was 0.88 (95% CI, 0.85-0.91) in the training cohort and 0.90 (95% CI, 0.86-0.92) in the validation data cohort, which was significantly greater than the AUC of each biomarker alone. For the nodule risk model, the AUC was improved to 0.96 (95% CI, 0.94-0.98) in the training cohort and 0.95 (95% CI, 0.93-0.97) in the validation cohort. In addition, the biomarker panel model yielded an AUC of 0.78 (95% CI, 0.74-0.81) for stage I & II lung cancer, better than the performance of individual biomarker alone. Conclusions: It was demonstrated that 4-protein biomarker panel had a significant performance in identifying lung cancer patients from healthy controls, especially combining with the nodule size. Specifically, it yielded excellent discrimination for identifying early-stage lung cancer patients than individual biomarker alone. A future large-scale study is underway to further define the clinical application of this method for the early diagnosis of lung cancer among Chinese populations.

IL-15 promotes regulatory T cell function and protects against diabetes development in NK-depleted NOD mice.

IL-15, an anti-apoptotic cytokine, has been reported to promote the survival and function of NK cells and T cells, including regulatory T cells (Tregs). Here we examined the effect of repeated injections of IL-15 on the development of diabetes in NOD mice. Injection of recombinant murine IL-15, once a day for 2 weeks, neither inhibited nor accelerated diabetes development in untreated NOD mice. However, treatment with IL-15 significantly reduced the incidence and delayed the onset of diabetes in NOD mice that were depleted of NK cells, while NK cell depletion alone had no protection against the disease development. The protective effect in IL-15-treated, NK cell-depleted NOD mice was associated with an increase in immunosuppressive activity of CD4(+)CD25(+) Tregs. IL-15 also enhanced Foxp3 expression in CD4(+)CD25(+) cells in an in vitro culture system, and such an effect of IL-15 was abrogated by IL-15-activated NK cells. Inhibition of IL-15-induced Foxp3 expression by IL-15-activated NK cells likely resulted from their IFN-gamma production, as recombinant IFN-gamma, or the culture supernatant of IL-15-activated wild-type mouse NK cells but not of IL-15-activated IFN-gamma-deficient NK cells, mediated a similar inhibition. IFN-gamma also diminished the stimulatory effect of IL-15 on Treg function in vitro. These results indicate that IL-15 has the potential to promote Treg function and protect against diabetes development in NOD mice, but such an activity can be eliminated by simultaneous activation of NK cells in IL-15-treated mice.

Microenvironment-activated nanoparticles for oxygen self-supplemented photodynamic cancer therapy.

Tumor hypoxia, as a hallmark of most solid tumors, poses a serious impediment to O2-dependent anticancer therapies, such as photodynamic therapy (PDT). Although utilizing nanocarriers to load and transport O2 to tumor tissues has been proved effective, the therapeutic outcomes have been impeded by the low O2 capacity and limited tumor penetration of the nanocarriers. To address these problems, we incorporated perfluorooctyl moieties into nanocarriers to improve the encapsulation of perfluorooctyl bromide via fluorophilic interactions, leading to elevated O2 capacity of the nanocarriers. Meanwhile, to enhance the tumor cell penetrating ability as well as reduce reticuloendothelial system recognition, the nanocarrier was further decorated with a cell-penetrating peptide, which was masked with a protecting group via an acid-labile amide bond for prolonged circulation time and acid-activated cell penetration. The in vitro study demonstrated that, apart from remarkably boosting the photocytoxicity of chlorin 6 (Ce6) at a low dosage, the rationally designed O2@DANPCe6+PFOB could even alleviate the pre-existing tumor hypoxia. After intravenous injection, O2@DANPCe6+PFOB exhibited significant tumor accumulation and retention, and potent tumor growth inhibition compared to traditional PDT. Overall, the O2@DANPCe6+PFOB mediated O2 self-supplemented PDT with tumor acidic microenviornment-activated cell penetration provides a promising strategy in anticancer treatment.

An Erythrocyte Membrane-Associated Antigen, PvTRAg-26 of Plasmodium vivax: A Study of Its Antigenicity and Immunogenicity.

Background:Plasmodium tryptophan-rich (TR) proteins have been proposed as potential vaccine candidate antigens. Among them, P. vivax tryptophan-rich antigens (PvTR-Ags), which have positionally conserved tryptophan residues in a TR domain, are highly antigenic in humans. Several of these antigens, including PvTRAg-26, have exhibited erythrocyte-binding activities. Methods: Subclasses of IgG antibodies against PvTRAg-26 were detected by enzyme-linked immunosorbent assay in 35 P. vivax infected patients and mice immunized with the recombinant antigen to characterize its antigenicity and immunogenicity. Moreover, the antigen-specific immune responses and Th1/Th2-type cytokine patterns of splenocytes from the immunized animals were determined in vitro. The subcellular localization of PvTRAg-26 in ring-stage parasites was also detected by indirect immunofluorescence assay. Results: The IgG1 and IgG3 levels in P. vivax-infected patients were significantly higher than those in uninfected individuals. In the PvTRAg-26-immunized mice, elevated levels of antigen-specific IgG antibodies were observed, dominated by the IgG1 subclass, and Th1-type cytokines were remarkably increased compared with Th2-type cytokines. Additionally, the subcellular location of the PvTRAg-26 protein was closely associated with the caveola-vesicle complex on the infected-erythrocyte membrane in the early ring stage of P. vivax. Conclusions: PvTRAg-26, a P. vivax TR antigen, with high antigenicity and immunogenicity, induces Th1-cytokine response and increases production of IgG1 antibodies. This immune profiling study provided a substantial evidence that PvTRAg-26 may be a potential candidate for P. vivax vaccine development.

Long-term survival and differentiation of human thymocytes in human thymus-grafted immunodeficient mice.

Aim: Thymus transplants have produced encouraging clinical outcomes in achieving thymopoiesis and T-cell development. This study was aimed to investigate whether human thymus contains self-renewing lymphoid progenitors capable of maintaining long-term T-cell development. Materials & methods: Immunodeficient mice were transplanted with human thymic tissue along with autologous GFP-expressing or allogeneic CD34+ cells and followed for human thymopoiesis and T-cell development from the thymic progenitors versus CD34+ cells, which can be distinguished by GFP or HLA expression. Results: In both models, long-term thymopoiesis and T-cell development from the thymic grafts were detected. In these mice, human thymic progenitor-derived T cells including CD45RA+CD31+CD4+ new thymic emigrants were persistently present in the periphery throughout the observation period (32 weeks). Conclusion: The results indicate that human thymus contains long-lived lymphoid progenitors that can maintain durable thymopoiesis and T-cell development.

Posttransplant Hemophagocytic Lymphohistiocytosis Driven by Myeloid Cytokines and Vicious Cycles of T-Cell and Macrophage Activation in Humanized Mice.

Hemophagocytic lymphohistiocytosis (HLH) has recently been increasingly reported as an important complication after stem cell transplantation, in line with the increase in the number of HLA-mismatched transplantation. Although previous clinical studies have shown an elevation of inflammatory cytokines in patients with HLH after hematopoietic stem cell transplantation, as well as those after viral infection or autoimmune disease, the disease pathogenesis remains poorly understood. Here we explored this issue in humanized mice with functional human lymphohematopoietic systems, which were constructed by transplantation of human CD34+ cells alone, or along with human fetal thymus into NOD/SCID/γc-/- (NSG) or NSG mice carrying human SCF/GM-CSF/IL-3 transgenes (SGM3). In comparison with humanized NSG (huNSG) mice, huSGM3 mice had higher human myeloid reconstitution and aggressive expansion of human CD4+ memory T cells, particularly in the absence of human thymus. Although all huNSG mice appeared healthy throughout the observation period of over 20 weeks, huSGM3 mice developed fatal disease characterized by severe human T cell and macrophage infiltrations to systemic organs. HuSGM3 mice also showed severe anemia and thrombocytopenia with hypoplastic bone marrow, but increased reticulocyte counts in blood. In addition, huSGM3 mice showed a significant elevation in human inflammatory cytokines including IL-6, IL-18, IFN-α, and TNF-γ, faithfully reproducing HLH in clinical situations. Our study suggests that posttransplant HLH is triggered by alloresponses (or xenoresponses in our model), driven by myeloid cytokines, and exacerbated by vicious cycles of T-cell and macrophage activation.