Immune Cell Subgroups in Covid 19 Patients
Condition: Covid19
MeSH terms: COVID-19
Study type: Observational

Summary: 
      COVID-19, spreading rapidly all over the world, causes serious morbidity and mortality. In
      severe COVID-19 infections, after pulmonary inflammation, cardiovascular organ failure,
      cytokine storm, hemophagocytosis, septic shock, develops due to uncontrolled hypoxia, and
      isolated organ failure turns into multi-organ failure. It is noteworthy that it causes
      lymphopenia in patients. In studies conducted, the effects of Covid-19 on the immune system
      were evaluated with limited parameters. In addition, no study evaluating the effect of this
      disease on the immune system has been published in our country.
    

Detailed description: 
      The causative agent of coronavirus 2019 (COVID-19) disease, which started in Wuhan province
      of China in December 2019, was severe acute respiratory failure syndrome coronavirus 2
      (SARS-CoV-2), which quickly spread all over the world and caused a pandemic. COVID-19 can
      cause death with symptoms such as fever, cough, muscle pain, shortness of breath, and
      pneumonia (1). Pulmonary pathology of COVID-19 is diffuse alveolar damage, focal reactive
      hyperplasia of pneumocytes with patchy inflammatory cells, intravascular thrombosis,
      monocyte, macrophage and lymphocyte infiltration into pulmonary spaces. Severe infiltration
      of pulmonary tissue affects alveolar gas exchange. In addition, cardiovascular morbidity,
      tachyarrhythmia and thromboembolic events are observed in 1/5 of the hospitalized patients
      with troponin elevation, which is closely related to mortality. In severe COVID-19
      infections, after pulmonary inflammation, cardiovascular organ failure, cytokine storm,
      hemophagocytosis, septic shock, develops due to uncontrolled hypoxia, and isolated organ
      failure turns into multi-organ failure.

      It is noteworthy that it causes lymphopenia in patients. In the studies conducted, the
      effects of Covid-19 on the immune system and the determination of cell subgroups were
      performed with limited parameters. No studies have been conducted on PDL-1, one of the immune
      control points. In addition, no study evaluating the effect of this disease on the immune
      system with wide parameters has been published in our country.

      We aimed to study CD3 (+) lymphocytes, CD4 (+) lymphocytes, CD 8 (+) lymphocytes, CD
      3(-)/CD16 (+) NK cell ratio, CD14 (+) lymphocytes, and HLA-DR positivity on CD14 (+) cells at
      Covid-19 and healthy volunteers.
    

Intervention name(s): Flow cytometric analysis
Intervention type(s): Diagnostic Test
Intervention description(s): Flow cytometric analysis of T helper, T cytotoxic cells, NK cells and monocytes
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Patients who admitted to the emergency department with the complaint of respiratory
        failure, lymphopenia in blood tests and Covid 19 (+) in the PCR tests are case group.

        Also healty volunteers who don't have complaint of respiratory failure, lymphopenia in
        blood tests and Covid 19 (-) in the PCR tests are control group.
      
Keywords: T helper cell; T cytotoxic cell; Monocyte; NK cell