Pneumocystis jirovecii is a fungus that causes Pneumocystis pneumonia (PCP) in humans which remains a leading opportunistic infection associated with AIDS patients, even in the era of Highly Active Anti-Retroviral Therapy (HAART). PCP increasingly targets new groups of patients with underlying chronic disease states, such as patients receiving anti-TNF therapy, other immunosuppressive agents and with underlying chronic diseases such as Chronic Obstructive Pulmonary Disorder (COPD). The combination therapy of trimethoprim- sulfamethoxazole (TMP-SMX) remains the standard prophylactic and therapeutic modality in use today with few alternative treatments. Evidence for mutations associated with resistance to sulfamethoxazole has been identified in the P. jirovecii dihydropteroate synthase encoding gene. It is thus critical that new approaches to anti-PCP therapy be developed. In this proposal, we will build on our previous observations that slightly acidified nitrite (A-NO2-), a nitric oxide (NO) generator, was effective in preventing the formatio of in vitro biofilms by Pneumocystis carinii and decreased viability in standard suspension cultures. Ongoing toxicology studies in dogs and rats and Phase I human trials revealed A-NO2- was well tolerated at doses up to 19-20 mg/kg, respectively, with minimal side effects, which bodes well for translation of these efforts. We propose to evaluate 2 different delivery modes for A-NO2- in therapeutic and prophylaxis mouse models of PCP at 3 different doses to determine the most effective administration route and treatment times that reduce fungal lung burdens. Initial immunological studies will guide further mechanistic experiments to determine the mode of action of this new alternative agent.

Public Health Relevance

Pneumocystis jirovecii is a fungus that causes Pneumocystis pneumonia (PCP) in humans and has few treatment options. A new agent, slightly acidified nitrite (A-NO2-), will be explored as a new and novel treatment for this lethal infection.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Small Research Grants (R03)
Project #
5R03AI117587-02
Application #
9089921
Study Section
Lung Cellular, Molecular, and Immunobiology Study Section (LCMI)
Program Officer
Xu, Zuoyu
Project Start
2015-06-15
Project End
2017-05-31
Budget Start
2016-06-01
Budget End
2017-05-31
Support Year
2
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of Cincinnati
Department
Genetics
Type
Schools of Medicine
DUNS #
041064767
City
Cincinnati
State
OH
Country
United States
Zip Code
45221