Antimicrobial Resistance : Part 2

by National Institute of Health

(Page 2 of 2)

NIAID Research

The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), funds research, drug development, and clinical trials to combat the problem of antimicrobial resistance. NIAID manages a research portfolio of grants specifically aimed at the problem of antibiotic resistance among common bacteria responsible for hospital-acquired infections. These grants fund studies on the basic biology of resistant organisms, applied research on new diagnostic techniques, therapies, and preventive measures, studies of how bacteria develop and share resistance genes.

Other NIAID-funded research projects seek to identify natural antimicrobial peptides (small pieces of protein molecules) that could help stave off resistant infections.

Under a new research initiative, Sepsis and CAP: Partnerships for Diagnostics Development, NIAID has funded multiple projects to support industry development of broad diagnostic technologies. The goal is early detection of septicemia, bacteremia, candidemia, and community-acquired pneumonia.

NIAID is sponsoring a trial to test the effectiveness of two infection control strategies for reducing MRSA and vancomycin-resistant enterococci colonization and infection in intensive care units. The Strategies to Reduce Transmission of Antimicrobial Resistant Bacteria in Intensive Care Units trial involves 20 hospitals collaborating with the NIH Clinical Center.

NIAID also supports the Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA). NARSA is a multidisciplinary international cadre of scientists conducting basic and clinical research focused on combating antimicrobial resistant S. aureus and related staphylococcal bacterial infections. The network maintains a repository of antibiotic-resistant staphylococcus strains that scientists can request for use in their research. NARSA's Web site (www.narsa.net ) offers scientific presentations and a discussion forum to promote communication among researchers.

NIAID also supports a number of networks conducting clinical trials to evaluate new antimicrobial drugs and vaccines.

The AIDS Clinical Trials Group evaluates drugs that combat the problem of HIV resistance to standard antiretroviral treatments.

The Bacteriology and Mycology Study Group, a network of academic and private research institutes, conducts clinical trials to improve treatments for fungal infections, particularly in people with weakened immune systems.

The Collaborative Antiviral Study Group, made up of researchers from approximately 50 institutions, evaluates experimental therapies for viral infections.

NIAID's Vaccine and Treatment Evaluation Units are a network of seven U.S. institutions that conduct clinical research to speed development of new vaccines and therapies.

Other research projects at NIH or funded by NIH are seeking new, molecular-level knowledge on the interactions of microbes and human cells as well as the tricks microbes use to thwart antibiotics. Another avenue of research is sleuthing the genomes of drug-resistant bacteria for vulnerabilities that could be attacked with new or existing drugs.

Antimicrobial Advances and Activities

NIAID-funded research grants and activities are yielding results that will help public health officials hold the line in our fight against drug-resistant microbes. Some examples follow.

NIAID-supported scientists followed the expression of virulence genes during S. aureus infection. They found that these genes are not expressed immediately upon infection, when low bacteria numbers would be overwhelmed by the host immune system. Instead, the bacteria monitor their cell number and density, waiting until there is a critical mass before expressing virulence genes. Experiments that interfered with self-monitoring also interfered with abscess formation, thus limiting pathogenicity. These results demonstrate that inhibiting expression of virulence genes for just a short time can have therapeutic value, but this value would only be significant if treatment were started early.

At The Institute for Genomic Research, NIAID is supporting development of proteomic profiling strategies to analyze surface proteins present in organisms such as S. aureus strains that are resistant to intermediate levels of vancomycin. These surface proteins play a role in virulence and survival in bacterial infections. Further research holds promise for elucidating mechanisms of virulence and antibiotic resistance.

NIAID-funded researchers have identified the molecular structure formed between a particular S. aureus protein and collagen, a ubiquitous eukaryotic structural protein. Understanding the mechanism by which S. aureus adheres to host structures helps to elucidate the infection process and could eventually lead to vaccines to thwart staphylococcal infections.

One of the negative impacts of using systemic antibiotics for localized infections is that the drug circulates throughout the body killing off both beneficial and detrimental microbes. This also unnecessarily subjects the native microflora to antibiotic selection. NIAID-supported scientists are using a form of buckminsterfullerene as a photosensitizer and combining that with visible light to generate reactive oxygen that kills off infecting bacteria at the site of infection.

About the Author

NIH is the nation's medical research agency - making important medical discoveries that improve health and save lives. The National Institutes of Health (NIH), a part of the U.S. Department of Health and Human Services, is the primary Federal agency for conducting and supporting medical research.