Predictive In Vitro Vitreous and Serum Models and Methods to Assess Thiol-Related Quality Attributes in Protein Therapeutics.

In vitro models that mimic the in vivo environment can greatly facilitate and support criticality assessment of product quality attributes for therapeutic drugs to ensure product quality. An in vitro model is established to study and predict the impact of thiol-related attributes on safety or efficacy of intraocular antibody products. This model simulates the physiological redox environment of rabbit vitreous and maintains a steady-state redox potential using reduced and oxidized forms of glutathione. A similar in vitro model that mimics the thiol redox conditions of human blood has been previously established and has become a predictive tool to study intravenous (IV) therapeutic proteins. We utilized both vitreous and serum models to study the potential impact of antibody variants (trisulfides and free-thiols) on product qualities of different antibodies. The studies demonstrate that both models are effective tools to monitor changes of thiol-related attributes under physiological conditions, providing insights on these thiol-related attributes and allowing for more informed assessment of biological relevance and criticality of the attributes. Furthermore, we propose that the approach using an in vitro study for the product quality attribute assessment can be used to predict in vivo effects for future molecules during the development of biopharmaceuticals, reducing the need for live subject studies.

Post-traumatic Fungal Keratitis and Endophthalmitis Caused by Coniochaeta Hoffmannii with Late Recurrence following Therapeutic Full-thickness Penetrating Keratoplasty.

BACKGROUND: To report a rare case of fungal keratitis and endophthalmitis due to Coniochaeta hoffmannii. METHODS: Case report. RESULTS: A 71-year-old immunocompetent male sustained a corneal laceration, traumatic cataract, and retinal detachment due to penetrating injury from a nail pulled from a wooden deck. The patient's postoperative course was complicated by infectious keratitis. Fungal cultures, DNA sequencing and analysis of the internal transcribed spacer sequence confirmed Coniochaeta hoffmannii. Topical and oral voriconazole treatments were initiated; however, due to impending perforation, a therapeutic corneal transplant was required. One year later, the patient developed a new corneal infiltrate at the graft-host junction: Corneal scrapings were culture positive for Coniochaeta hoffmannii. This was treated with topical and intrastromal voriconazole along with oral itraconazole 200 mg once daily for 8 months. CONCLUSIONS: Coniochaeta hoffmannii may cause recalcitrant keratitis and endophthalmitis, which required longstanding antifungal treatment.

Comparison of the FXG™: RESP (Asp+) real-time PCR assay with direct immunofluorescence and calcofluor white staining for the detection of Pneumocystis jirovecii in respiratory specimens.

We compared the FXG™: RESP (Asp +) real-time PCR assay (Myconostica Ltd) with two microscopic staining methods (direct immunofluorescence [IFA] and calcofluor white) for the detection of Pneumocystis jirovecii in 411 respiratory specimens submitted for P. jirovecii examination. We considered the specimen to be microscopically positive if the organism could be visualized through the use of either IFA or calcofluor white. A second, published real-time PCR assay targeting the cdc2 gene of P. jirovecii was used to adjudicate those specimens that were microscopically negative but Myconostica PCR positive. The Myconostica PCR positive samples were deemed to be true positives if they were concordant with microscopically positive results or if they were positive by the second PCR assay. As a result, the Myconostica PCR assay was found to be more sensitive than the two microscopy methods in detecting P. jirovecii (10.5% true positivity rate by PCR, 8.0% by immunofluorescence, and 7.1% by calcofluor white). The Myconostica PCR assay showed 93.5% sensitivity, 95.1% specificity, 70.5% positive predictive value, and 99.1% negative predictive value. Its high negative predictive value suggests a role of the Myconostica PCR assay in ruling out Pneumocystis pneumonia.

Fungal keratitis caused by Metarhizium anisopliae complex.

PURPOSE: To report a case of fungal keratitis caused by Metarhizium anisopliae complex. METHODS: Case report. RESULTS: Our patient presented with a central corneal infiltrate. Fungal culture yielded a Metarhizium species. She was started on antifungal agents with no significant improvement. A therapeutic corneal transplant was performed after perforation. At two years follow up, she was free of infection. CONCLUSION: Metarhizium anisopliae is a very rare cause of keratitis. Although previous reported cases showed clinical improvement with antifungal agents, this case required surgical treatment to control the infection.

Cytological, microbiological and therapeutic aspects of systemic infection in a dog caused by the fungus Phialosimplex caninus.

A seven-year-old immunocompetent dog presenting with lymphadenopathy, mesenteric masses and splenic nodules was diagnosed with Phialosimplex caninus infection. Cytology of a mesenteric mass aspirate demonstrated few intact cells but numerous variably sized fungal cells and rare hyphal fragments. The identity of the cultured fungus was confirmed by DNA sequencing. Itraconazole therapy improved clinical signs, but the fungus was reisolated at follow-up. P. caninus systemic infection should be suspected in dogs presenting with lymphadenopathy and splenomegaly.