RECRUITING

Molecular Basis of Human Phagocyte Interactions With Bacterial Pathogens

Study Overview

This clinical trial focuses on testing the efficacy of different digital interventions to promote re-engagement in cancer-related long-term follow-up care for adolescent and young adult (AYA) survivors of childhood cancer.

Description

Human phagocytic cells such as polymorphonuclear leukocytes (PMNs) are readily mobilized to sites of infection and ingest microorganisms by a process known as phagocytosis. The combined effects of reactive oxygen species (ROS) and proteolytic peptides and enzymes released into forming bacterial phagosomes kill most ingested bacteria. However, many human bacterial pathogens have devised means to subvert normal phagocyte responses and the innate immune response and cause severe disease. The overall objective of this study is to elucidate specific features of pathogen-phagocyte interactions that underlie evasion of the innate immune response or contribute to the pathophysiology of disease or inflammatory disorders. Therefore, specific projects will: 1. Identify and characterize specific mechanisms used by pathogenic microorganisms to evade or subvert normal phagocyte responses and therefore cause disease. 2. Investigate phagocyte response mechanisms to specific pathogenic microorganisms. 3. Identify specific bacterial structures and/or (gene) products that dictate differences in phagocyte responses among a range of pathogens so that generalized statements can be made about the pathophysiology of disease states. The studies will be performed using multiple techniques including state-of-the-art equipment for genomics and proteomics strategies to identify target bacterial genes/proteins of interest or those up-regulated in phagocytes. Phagocyte-pathogen interactions will be examined using fluorescence-based real-time assays and video microscopy, confocal and electron microscopy in combination with enzymatic assays for ROS production, routine biochemistry, immunology and cell biology. Implementing these studies will require isolation of phagocytic leukocytes from venous blood of healthy human volunteers. The study population will be all-inclusive except in certain instances where individuals possess genetic defects that impair phagocyte function (e.g., myeloperoxidase-deficiency) or have altered phagocyte function due to outside influences such as recent bacterial or viral infection. The proposed studies will likely provide new information pertinent to understanding host cell-pathogen interactions and the pathophysiology of inflammatory conditions.

Official Title

Molecular Basis of Human Phagocyte Interactions With Bacterial Pathogens

Quick Facts

Study Start:2001-02-12
Study Completion:N/A
Study Type:Not specified
Phase:Not Applicable
Enrollment:Not specified
Status:RECRUITING

Study ID

NCT00339287

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Ages Eligible for Study:18 Years to 120 Years
Sexes Eligible for Study:ALL
Accepts Healthy Volunteers:Yes
Standard Ages:ADULT, OLDER_ADULT
Inclusion CriteriaExclusion Criteria
  1. Age 18 years or older
  2. Willing and able to provide informed consent
  3. Able to understand and follow study procedures
  4. Stable medical condition
  1. * Subjects must fit the definition of "healthy adults" as assessed by the medical/health screening evaluations, and willing to have blood and/or tissue samples stored for future use.
  2. * Inasmuch as all subjects are RML employees, they will be 18 years of age or older.
  3. * Children are excluded.
  4. * Pregnant women will be identified by verbal history and are not eligible to donate blood for this protocol.
  5. * The study population will be all-inclusive except in certain instances where individuals possess genetic defects that impair phagocyte function (e.g., myeloperoxidase-deficiency) or have altered phagocyte function due to outside influences such as recent bacterial or viral infection.
  6. * Individuals below the normal hematocrit and hemoglobin ranges will be excluded from the protocol.

Contacts and Locations

Study Contact

Frank R De Leo, Ph.D.
CONTACT
(406) 363-9448
fdeleo@niaid.nih.gov

Principal Investigator

Frank R De Leo, Ph.D.
PRINCIPAL_INVESTIGATOR
National Institute of Allergy and Infectious Diseases (NIAID)

Study Locations (Sites)

NIAID, Rocky Mountain Laboratories
Hamilton, Montana, 59840
United States

Collaborators and Investigators

Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)

  • Frank R De Leo, Ph.D., PRINCIPAL_INVESTIGATOR, National Institute of Allergy and Infectious Diseases (NIAID)

Study Record Dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Registration Dates

Study Start Date2001-02-12
Study Completion DateN/A

Study Record Updates

Study Start Date2001-02-12
Study Completion DateN/A

Terms related to this study

Keywords Provided by Researchers

  • Virulence
  • PHAGOCYTOSIS
  • Neutrophil
  • Pathogenesis
  • Natural History

Additional Relevant MeSH Terms

  • Host Defense Mechanisms