Tararaj Dharakul

Age-related immune decline is basically recognized as a key contributor to frailty. However, associations between immune markers, including T cell subsets,

HIV-infected patients are at increased risk of human papillomavirus (HPV) acquisition and HPV-associated diseases. This study set out to determine whether a two-dose (2D) HPV vaccination schedule was sufficient in HIV-infected adolescents with immune reconstitution (IR) following antiretroviral treatment. Participants aged 9–15 years who had CD4 cell counts > 500 cells/mm³ and HIV-1 RNA < 40 copies/mL for at least one year were assigned to the 2D schedule, while older participants or those without IR received a three-dose (3D) schedule. Antibodies to HPV-16 and -18 were measured using a pseudovirion-based neutralization assay. A total of 96 subjects were enrolled; 31.3% and 68.7% received the 2D and 3D schedule, respectively. Of these, 66.7% and 57.6% of the 2D and 3D participants, respectively, were male. The seroconversion rates for HPV-16 and HPV-18 were 100% in all cases, except for HPV-18 in males who received the 3D schedule (97.4%). In males, the anti-HPV-16 geometric mean titers (GMTs) were 6859.3 (95% confidence interval, 4394.3–10,707.1) and 7011.1 (4648.8–10,573.9) in the 2D and 3D groups (p = 0.946), respectively, and the anti-HPV-18 GMTs were 2039.3 (1432.2–2903.8) and 2859.8 (1810.0–4518.4) in the 2D and 3D (p = 0.313) groups, respectively. In females, the anti-HPV-16 GMTs were 15,758.7 (8868.0–28,003.4) and 26,241.6 (16,972.7–40,572.3) in the 2D and 3D groups (p = 0.197), respectively, and the anti-HPV-18 GMTs were 5971.4 (3026.8–11,780.6) and 9993.1 (5950.8–16,781.1) in the 2D and 3D groups (p = 0.271), respectively. In summary, a 2D schedule is as immunogenic in young adolescents with IR as a 3D schedule in older subjects and those without IR.

MPRCA-GO sensor can detect low amount of miRNAs, which are biomarkers in cancer diagnosis.

Biological RNA generally comprises secondary structure motifs which cause a problem for target RNA detection by isothermal amplification methods. The complexity of the secondary structures makes RNA targets inaccessible for probe hybridization, resulting in decreased sensitivity and selectivity. This is particularly important because the hybridization step of the isothermal amplification method requires a limited temperature range. A strand-displacement strategy can enhance the hybridization efficiency between the probe and target RNA with secondary structure motifs. A short, single-stranded segment within the secondary structure can be used as a toehold for initiating strand displacement. The strategy has been used to establish a highly sensitive isothermal amplification by a combination of a hairpin probe hybridization and strand-displacement amplification. The hairpin probe is placed on the single-stranded segment of the target RNA’s secondary structure to initiate strand displacement. The probe’s hybridization cascade provides a template for exponential amplification in two directions by strand-displacement amplification, designated hybridization cascade plus strand-displacement isothermal amplification (HyCaSD). The method requires no reverse transcription step. HyCaSD showed an excellent sensitivity with the limit of detection in the femtomolar (fM) range for synthetic targets as well as viral RNAs. Discrimination between DENV/ZIKV and JEV/CHIKV was successfully demonstrated using real viruses. Therefore, HyCaSD is a promising platform that can be further developed for diagnostic applications.

The development of targeted contrast agents for magnetic resonance imaging (MRI) facilitates enhanced cancer imaging and more accurate diagnosis. In the present study, a novel contrast agent was developed by conjugating anti-EpCAM humanized scFv with gadolinium chelate to achieve target specificity.

Epithelial cell adhesion molecule (EpCAM) is a promising biomarker for squamous cell carcinoma (SCC) of the uterine cervix, because it is over-expressed in various cancers of epithelial origin. However, EpCAM expression reported in previous immunohistochemistry (IHC) studies was inconsistent. We hypothesize that the membrane-distal part of EpCAM may be lost during tissue preparation, leaving only the membrane-proximal part of EpCAM available for antibody binding and IHC staining. Two new anti-EpCAM MAbs to the membrane-proximal part (WC-2) and the membrane-distal part (WC-1) of EpCAM were generated and characterized. WC-2 was selected for its ability to detect EpCAM in cervical tissues by IHC. One hundred thirty-five archival paraffin-embedded tissues previously diagnosed as cervical SCC (n=44), high-grade (HSIL) (n=43), or low-grade (LSIL) (n=48) squamous intraepithelial lesions were examined. IHC score was collected, recorded, and analyzed for distribution, intensity, and percentage of cancer cells stained for EpCAM. EpCAM expression was consistently detected on cervical tissues by WC-2, but not by WC-1. EpCAM was expressed with high IHC score in the majority of cervical SCC (37/44), but not in normal epithelial area adjacent to SCC. EpCAM was also highly expressed on precancerous lesion of the cervix, particularly in HSIL. More importantly, EpCAM expression could be used to distinguish between HSIL and LSIL, according to staining distribution. HSIL tissues displayed EpCAM expression in two-thirds to full thickness of the epithelium, while in LSIL the staining was limited to the lower one-third of the thickness. The IHC score of EpCAM expression was strongly correlated with cervical cancer and grades of precancerous lesions (r=0.875, p<0.001). Only the anti-EpCAM MAb to the membrane-proximal part is able to detect EpCAM on paraffin-embedded cervical cancer tissues. A strong positive correlation between EpCAM expression level and the grades of SILs provides the possibility that EpCAM can be used to predict prognosis and severity in these patients.

A simple electrochemical aptasensor was developed for the detection of glycated albumin (GHSA) using ssDNA aptamer that selectively binds to GHSA as a recognition element. The biotinylated ssDNA aptamer was immobilized on a streptavidin-modified screen-printed carbon electrode (SPCE). The changes of interfacial features of the electrode surface, which were based on the aptamer-GHSA interaction, were probed in the presence of the redox Fe(CN)₆ ^3- using square wave voltammetry (SWV) measurements (Fig 1). The results showed that limit of detection of our sensor was 3 µg/ml, with a calibration curve to the range of 16 mg/ml. The aptasensor showed high selectivity for GHSA over other molecules that is usually available in the blood. Our aptasensor was successfully applied to detect GHSA in serum samples, which demonstrated the higher levels of GHSA concentrations in diabetes than normal persons. These indicate that our electrochemical aptasensor has a potential for diagnosis and monitoring of diabetes mellitus. Figure 1