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Immuno-fluorescence Assay of Leptospiral Surface-exposed Proteins
Published on: July 1, 2011
Cellular immune response analysis of patients with leptospirosis
E H Yamashiro-Kanashiro1, G Benard, M N Sato
1Department of Internal Medicine, Faculdade de Medicina da Universidade de Sao Paulo, Brazil.
Insights
Cellular immunity in leptospirosis patients shows altered lymphocyte subsets, including decreased CD4+ cells and increased B cells. However, the immune system appears resilient, suggesting a good prognosis despite acute renal failure.
Area of Science:
- Immunology
- Infectious Diseases
- Renal Medicine
Background:
- Leptospirosis is a bacterial infection with potential renal complications.
- Understanding the cellular immune response is crucial for managing severe leptospirosis.
- Acute renal failure (ARF) is a serious complication of leptospirosis.
Purpose of the Study:
- To investigate the cellular immunity status in patients with acute leptospirosis.
- To analyze lymphocyte subsets and their function in patients with and without ARF.
- To determine the impact of leptospirosis on immune cell populations and function.
Main Methods:
- Analysis of peripheral blood mononuclear cells (PBMC) using immunofluorescence.
- Assessment of lymphocyte subset distribution (CD3+, CD4+, B cells).
- Evaluation of PBMC proliferative response to phytohemagglutinin (PHA) and pokeweed mitogen (PWM).
- Investigation of serum effects on normal PBMC response.
Main Results:
- Decreased CD3+ and CD4+ T cell subsets observed in patients with and without ARF.
- Increased B lymphocyte numbers noted in all leptospirosis patients, persisting even after recovery.
- Reduced PHA response in patients with ARF, suggesting immune suppression.
- Leptospiral factors and patient sera may influence immune cell behavior and function.
Conclusions:
- Leptospirosis alters lymphocyte subsets and can suppress cellular immunity, particularly in the presence of ARF.
- The observed immune changes are likely influenced by leptospiral factors and serum activity.
- Despite alterations, the cellular immune system appears capable of recovery, correlating with a favorable prognosis.
Abstract:
Peripheral blood mononuclear cells (PBMC) from acute leptospirosis patients with and without acute renal failure were studied in order to investigate the status of cellular immunity in this disease. We analyzed the lymphocyte subsets of leptospirosis patients by immunofluorescence and their responsiveness to the mitogens phytohemagglutinin (PHA) and pokeweed mitogen (PWM). Additionally, we investigated the effect of the patients' sera on normal PBMC proliferative response. We observed a decrease in the CD3+ and CD4+ cell subsets in patients with and without acute renal failure, or in percentage values alone in those who had recovered from renal failure. An increase in the number of B lymphocytes was observed in all patients, compared with controls. This increase in B lymphocytes was seen even in patients who had recovered from renal failure, when the number of CD3+ and CD4+ lymphocytes had already returned to normal levels. The low PHA response observed only with lymphocytes from patients with acute renal failure suggests a suppressive effect. The proliferative response to PWM was comparable to controls, even in the patients with acute renal failure. This latter result and the expansion of the B cell number could be related to leptospiral-derived factor(s). We also showed that sera from patients with and without acute renal failure exerted some inhibitory activity on normal PBMC responses to PHA and PWM. Although the redistribution of lymphocyte subsets and the serum suppressor activity were related to acute renal failure and leptospiral factor(s), we suggest that the cellular immune system was not irreversibly affected, which is compatible with the good prognosis seen in the patients studied.
