Related Experiment Videos
Leukocyte membrane receptors in meningitis and other bacterial infections
Abstract:
Blood leukocytes from 37 patients with acute bacterial infections, and cerebrospinal fluid (CSF) granulocytes from 12 patients with bacterial meningitis, were examined for the distribution of membrane receptors (R) for (1) untreated sheep erythrocytes (E), (2) the Fc portion of IgG (Fc gamma), and (3) complement component C3b. We found a decreased percentage of granulocytes bearing Fc gamma-R in the CSF from patients with meningitis, and in blood from patients with respiratory tract infections. This group also had a decreased percentage of C3b-R bearing granulocytes on admission, whereas meningitis patients had lower levels of C3b-R and Fc gamma-R bearing granulocytes in the 2nd and 3rd week and even later. Several patients with meningitis and gastroenteritis had granulocytes bearing the E-R, previously considered specific for T lymphocytes. Such cells were also found in the CSF. Meningitis and respiratory tract infections were associated with a decreased percentage of 'active' T lymphocytes. The total percentage of T lymphocytes was also decreased in meningitis. Conversely the proportion of Fc gamma-R bearing lymphocytes (consisting mostly of B lymphocytes) was increased in most infections. During the first 3 weeks of bacterial meningitis, the percentages of Fc gamma- and C3b-R bearing granulocytes, and of Fc gamma-R bearing lymphocytes, gradually decreased, while the T lymphocyte percentage increased from the initial low values.
Insights
Bacterial infections alter immune cell receptors. Patients with meningitis and respiratory infections showed reduced granulocyte receptors, while lymphocyte receptors changed, indicating immune system shifts during infection.
Area of Science:
- Immunology
- Cell Biology
- Infectious Diseases
Background:
- Bacterial infections significantly impact the immune system.
- Understanding immune cell receptor distribution is crucial for diagnosing and managing infections.
Purpose of the Study:
- To investigate the distribution of specific membrane receptors on leukocytes and granulocytes in patients with bacterial infections.
- To analyze changes in receptor expression in blood and cerebrospinal fluid (CSF) during bacterial meningitis and other infections.
Main Methods:
- Analysis of blood leukocytes from 37 patients with acute bacterial infections.
- Examination of CSF granulocytes from 12 patients with bacterial meningitis.
- Assessed receptors for sheep erythrocytes (E), Fc portion of IgG (Fc gamma), and complement component C3b (C3b).
Main Results:
- Decreased Fc gamma-R and C3b-R on granulocytes in meningitis and respiratory infections.
- Presence of E-R on granulocytes in meningitis and gastroenteritis.
- Reduced 'active' T lymphocytes in meningitis and respiratory infections; decreased total T lymphocytes in meningitis.
- Increased Fc gamma-R bearing lymphocytes (B lymphocytes) observed in most infections.
Conclusions:
- Bacterial infections induce significant alterations in immune cell receptor expression.
- Changes in Fc gamma-R, C3b-R, and T lymphocyte percentages correlate with infection type and duration.
- The presence of E-R on granulocytes suggests a broader role than previously understood.