Objective: The objective was to study the association of Klotho gene G395A and C1818T single nucleotide polymorphisms with glycemia, serum, glycosylated hemoglobin (HbA1c) level and the risk of type 2 diabetes mellitus (T2DM) in the Pashtun population of Pakistan. Methods: In this study, 195 normal individuals and 217 T2DM patients were enrolled. All subjects were divided into three groups, namely overall subjects (control + T2DM patients), control individuals and T2DM patients, and their fasting glucose, HbA1c level, lipid profile and C1818T and G395A polymorphisms were determined. Results: The allele frequencies of G395A in overall subjects were 0.568 for A and 0.432 for G. Similarly, allele frequencies for G395A in overall subjects were 0.597 and 0.403 for C and T alleles, respectively. The AA genotype of G395A was observed to be a risk factor for T2DM. In normal individuals, no significant (p > 0.05) association was observed between klotho C1818T and G395A polymorphisms and hyperglycemia. In overall subjects, the C1818T polymorphism was associated (p < 0.05) with high fasting glucose and HbA1c levels in female subjects only. In T2DM patients, both C1818T and G395A polymorphisms were found to be significantly (p < 0.05) associated with high fasting glucose and HbA1c levels both in males and females. Conclusion: The G395A polymorphism was observed to increase the risk of T2DM. Both C1818T and G395 were associated with high fasting glucose and HbA1c levels in T2DM patients.

Accurate, non-invasive measurement of programmed death-ligand 1 (PD-L1) expression is crucial for the optimization of immune checkpoint inhibitor cancer treatments. We describe the radiosynthesis and preclinical assessment of a new technetium-99m ( ^99m Tc) conjugated immuno-SPECT agent, [ ^99m Tc]Tc-HYNIC–durvalumab, for PD-L1 imaging in vivo . Durvalumab was conjugated with hydrazinonicotinamide (HYNIC) through lysine residues using an N-hydroxysuccinimide (NHS) ester-based method and subsequently radiolabeled with technetium-99m ( ^99m Tc) in the presence of tricine and ethylenediamine-N,N′-diacetic acid (EDDA) as co-ligands. Radiochemical purity, physicochemical stability in physiologically relevant media, and immunoreactivity were determined. Specific binding affinity and kinetics of internalization were studied in PD-L1-positive A549 cells. Biodistribution and SPECT imaging were carried out in A549 xenograft-bearing mice and rabbits. Specificity was confirmed by co-injection with an excess of unlabeled durvalumab. ^99m Tc-HYNIC-Durvalumab had 98.14 ± 0.27 % radiochemical purity and good stability (>90 % intact at 4 h in serum). The tracer showed high PD-L1 affinity and extensive receptor-mediated binding (28.54 ± 0.65 % at 4 h). In vivo , tumor uptake at 4 h post-injection was 6.42 ± 0.11 %ID/g, significantly reduced by co-administration of excess unlabeled antibody (1.56 ± 0.05 %ID/g, p < 0.01). Tumor-to-background ratio was 3.84, allowing for high-contrast SPECT imaging that accurately defined PD-L1-expressing tumors. These findings support ^99m Tc-HYNIC-Durvalumab to be a highly specific, stable, and clinically translatable SPECT radiotracer for quantitative PD-L1 expression imaging. This agent has great promise to enable patient stratification and therapeutic monitoring in immuno-oncology. Further studies toward clinical translation is warranted.