Characterization of Antibacterial Antibodies in Patients With Cystic Fibrosis

Study Overview
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Brief Summary
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Most of the cystic fibrosis (CF) patients are or have been pulmonary colonized with bacteria such as Pseudomonas aeruginosa or Staphylococcus aureus. Aim of this study is to detect virulence factor neutralizing antibodies in the sera of the study population followed by B cell repertoire analyses to design B cell-derived neutralizing monoclonal antibodies. The functionality of neutralizing antibodies rests on inhibition of virulence factors by binding of crucial epitopes rather than merely the induction of opsonization. Focusing on patients with bacterial colonization/chronic infections or a history of an acute infection in the past, will increase the likelihood for identification of serum with neutralizing activity as in vivo antigen contact is a prerequisite for antibody development and maturation. Since virulence factors are essential for infection, dissemination and tissue damage, inhibition of these factors by developed neutralizing antibodies might contribute to a favorable outcome of life-threatening infections.

Official Title
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Identification and Characterization of Antibacterial Antibodies in Sera of Patients With Cystic Fibrosis

Conditions
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Pulmonary Cystic Fibrosis, Neutralizing Antibodies

Intervention / Treatment
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* Other: Blood sampling


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years Ability to give consent Normal vital signs including: Blood pressure systolic value 150 - 100 mmHg, diastolic value < 90 mmHg Respiratory rate < 20/min Oxygen saturation >92% Heart rate 50 - 110/min Body temperature <38°C Exclusion Criteria: Cytopenia (leukocytes < 1.500/µl, thrombocytes < 50.000/µl, Hemoglobin < 12 g/dl) Heart disease or pulmonary hypertension Body weight <50 kg (exclusion of blood sampling for B cell isolation) Blood donation, larger blood loss and/or major surgery in the last 8 (male) or 12 (female) weeks Any decline of the general state of health in the last 3 month including weight loss > 2kg, pulmonal exacerbation or increased impairment of pulmonary function (FEV1 < 50%)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with Cystic Fibrosis<br>Patients with pulmonary Cystic Fibrosis with or without bacterial colonization | Other: Blood sampling<br>* Screening: Blood sampling of 15 ml whole blood B cell isolation: Blood sampling of max. 400 ml whole blood or 6% of the total blood volume (♀ 65 ∓ 10 ml/kg; ♂ 77 ∓ 10 ml/kg)<br>|
| Control group<br>Healthy age- and sex-matched controls including healthy individuals and patients with acute or chronic bacterial infections | Other: Blood sampling<br>* Screening: Blood sampling of 15 ml whole blood B cell isolation: Blood sampling of max. 400 ml whole blood or 6% of the total blood volume (♀ 65 ∓ 10 ml/kg; ♂ 77 ∓ 10 ml/kg)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of antibacterial antibodies |  | 3 years |