Development of an anti-Pseudomonas aeruginosa therapeutic monoclonal antibody WVDC-5244

The rise of antimicrobial-resistant bacterial infections is a crucial health concern in the 21st century. In particular, antibiotic-resistant Pseudomonas aeruginosa causes difficult-to-treat infections associated with high morbidity and mortality. Unfortunately, the number of effective therapeutic interventions against antimicrobial-resistant P. aeruginosa infections continues to decline. Therefore, discovery and development of alternative treatments are necessary. Here, we present pre-clinical efficacy studies on an anti-P. aeruginosa therapeutic monoclonal antibody. Using hybridoma technology, we generated a monoclonal antibody and characterized its binding to P. aeruginosa in vitro using ELISA and fluorescence correlation spectroscopy. We also characterized its function in vitro and in vivo against P. aeruginosa. The anti-P. aeruginosa antibody (WVDC-5244) bound P. aeruginosa clinical strains of various serotypes in vitro, even in the presence of alginate exopolysaccharide. In addition, WVDC-5244 induced opsonophagocytic killing of P. aeruginosa in vitro in J774.1 murine macrophage, and complement-mediated killing. In a mouse model of acute pneumonia, prophylactic administration of WVDC-5244 resulted in an improvement of clinical disease manifestations and reduction of P. aeruginosa burden in the respiratory tract compared to the control groups. This study provides promising pre-clinical efficacy data on a new monoclonal antibody with therapeutic potential for P. aeruginosa infections.

The presence of two reduced function variants in CYP2C9 influences the acute response to glipizide

AIMS

To examine whether the presence of two common missense variants in the CYP2C9 gene (rs1799853, encoding Arg144Cys and denoted as *2, and rs1057910, encoding Ile359Leu and denoted as *3) influences the acute physiological response to a single glipizide dose in individuals naïve to diabetes medications.

METHODS

In the Study to Understand the Genetics of the Acute Response to Metformin and Glipizide in Humans (SUGAR-MGH), 786 individuals genotyped for rs1799853/rs41291560 (*2) and rs1057910/rs9332214 (*3) were treated with 5 mg glipizide in the fasting state. Glucose and insulin levels were measured at baseline, 30, 60, 90, 120, 180 and 240 min for calculation of phenotypic endpoints of glipizide response. The challenge was aborted as a result of hypoglycaemia, defined as glucose <2.8 mmol/l or hypoglycaemia-related symptoms.

RESULTS

Carriers with two reduced function alleles had a 50% larger insulin area under the curve than carriers with zero or one copy (P=0.037), although this finding was primarily driven by an individual with a robust insulin response. In adjusted analyses, the risk of aborting the glipizide challenge was doubled in two-copy carriers (P=0.034). No significant findings were observed in glucose-based endpoints.

CONCLUSIONS

Carriers of two reduced function alleles in CYP2C9 may experience an increased insulin response to glipizide and be predisposed to a higher risk of hypoglycaemia, although no effect of genotype was seen in glucose-based measurements. Further studies are needed to clarify the utility of CYP2C9 genotyping to guide sulfonylurea treatment.

Phenomenology and family history of affective disorder in Cushing's disease

Of 16 patients with Cushing's disease, 13 (81%) had lifetime diagnoses of major affective disorder according to DSM-III criteria. However, the rate of familial major affective disorder among these patients was significantly lower than that found among patients with major depression.

Fibromyalgia and major affective disorder: a controlled phenomenology and family history study

Fibromyalgia is a form of nonarticular rheumatism characterized by diffuse musculoskeletal pain. To investigate the relationship between fibromyalgia and major affective disorder, the authors evaluated 31 patients with fibromyalgia and 14 patients with rheumatoid arthritis for rates of current or past major affective disorder and family history of major affective disorder. Both the rate of major affective disorder and the familial prevalence of major affective disorder were significantly higher in the fibromyalgia patients than the rheumatoid arthritis patients. The results suggest that fibromyalgia may be related to major affective disorder.

Prevalence of anorexia nervosa and bulimia among young diabetic women

To assess the prevalence of anorexia nervosa and bulimia among young diabetic women, a questionnaire was sent to 264 young women with insulin-dependent diabetes mellitus in two clinical settings. Among the women who responded (30%), none reported a history of anorexia nervosa, but 28 (35%) reported a history of bulimia. These results suggest that bulimia represents a common problem among young women with diabetes.

Abnormal results of dexamethasone suppression tests in nondepressed patients with diabetes mellitus

To investigate the specificity of the dexamethasone suppression test (DST) for the diagnosis of major depression in patients with diabetes mellitus, we administered 1 mg of dexamethasone to 30 nondepressed diabetics and to 58 normal controls at 11 PM. Diabetic subjects received hemoglobin A1 (Hb A1) determinations, the Hamilton Rating Scale for Depression (HRSD), and five to eight blood glucose determinations during the 48 hours surrounding the DST. Results demonstrated a significantly higher rate of nonsuppression (plasma cortisol level, greater than or equal to 5 micrograms/dL) at 4 PM the following day among diabetics (43%) than among controls (7%) but no difference between these groups in the rate of nonsuppression at 8 AM. Plasma cortisol level at 4 PM correlated with Hb A1 level but not with duration of illness, HRSD score, mean blood glucose level, or maximum blood glucose excursion. These results suggest that the results of the DST used as a diagnostic test for major depression must be interpreted with caution in patients with diabetes.

Hypothalamic-pituitary-adrenal-axis hyperactivity in bulimia

Hyperactivity of the hypothalamic-pituitary-adrenal axis, demonstrated by nonsuppression of plasma cortisol in the dexamethasone suppression test (DST), has been found in about 50% of patients with major depression. We administered the DST to 47 patients with bulimia and to 22 age- and sex-matched normal controls. Among the bulimics, 47% were nonsuppressors, significantly higher than the 9% prevalence of nonsuppressors in the controls, but similar to the prevalence reported for patients with major depression in other studies. This finding is consistent with evidence from studies of phenomenology, family history, and treatment response which suggest that bulimia may be related to affective disorder.