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临床试验/NCT00339287
NCT00339287招募中不适用

Molecular Basis of Human Phagocyte Interactions With Bacterial Pathogens

National Institute of Allergy and Infectious Diseases (NIAID)1 个研究点 分布在 1 个国家目标入组 200 人开始时间: 2001年2月12日最近更新:
适应症

试验速览

阶段
不适用
状态
招募中
入组人数
200
试验地点
1
主要终点
identify and characterize specific mechanisms used by pathogenic microorganisms to evade or subvert normal phagocyte responses and therefore cause disease.

研究概览

简要总结

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....

详细描述

Human phagocytic cells such as polymorphonuclear leukocytes (neutrophils or 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 antimicrobial peptides released into forming bacterial phagosomes kill most ingested bacteria. However, many bacterial pathogens have devised means to evade normal phagocyte responses and cause severe disease in humans.

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, projects will address 3 specific aims:

  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.

研究设计

研究类型
Observational
观察模型
Other
时间视角
Other

入排标准

年龄范围
18 Years 至 120 Years(Adult, Older Adult)
性别
All
接受健康志愿者

入选标准

  • INCLUSION &

排除标准

  • Volunteers will be selected from a healthy adult population, 18 years of age or older, with no known medical problems and will generally be NIH employees working at Rocky Mountain Laboratories (RML) or within the community of Hamilton, MT.
  • No race or gender is excluded from the donor pool and reflects the diversity of the community and that of the employees at RML.
  • The specific criteria for eligibility are as follows:
  • 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.
  • Inasmuch as all subjects are RML employees, they will be 18 years of age or older.
  • Children are excluded.
  • Pregnant women will be identified by verbal history and are not eligible to donate blood for this protocol.
  • 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.
  • Individuals below the normal hematocrit and hemoglobin ranges will be excluded from the protocol.

研究组 & 干预措施

Healthy volunteers

Healthy adult volunteers at least 18 years of age.

结局指标

主要结局

identify and characterize specific mechanisms used by pathogenic microorganisms to evade or subvert normal phagocyte responses and therefore cause disease.

时间窗: Ongoing

The study involves the use of human subjects as a source of blood for in vitro assays with bacteria, the isolation of hematopoietic cells (polymorphonuclear leukocytes, mononuclear phagocytes, erythrocytes, and lymphocytes), and serum as a source of complement, antibody, and matrix-binding proteins.

次要结局

未报告次要终点

研究者

申办方类型
Nih
责任方
Sponsor

研究点 (1)

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