Detection of B-cell populations with monotypic light chain expression in cerebrospinal fluid specimens from patients with multiple sclerosis by polychromatic flow cytometry

Analysis of cerebrospinal fluid cells by flow cytometry: Comparison to conventional cytology

AIMS

This study compared the results obtained by basic immunophenotyping of cerebrospinal fluid (CSF) cells by flow cytometry (FC) to the results of conventional cytology and evaluated the possibility of detailed analyses of CSF B-cell subpopulations.

METHODS

Samples from 42 patients were examined by conventional cytology (native and/or pre-centrifuged CSF) and FC. The results from 15 patients without evidence of organic neurological disease were used to estimate reference ranges.

RESULTS

Pre-centrifugated CSF had significantly higher cell yield on the cytologic slide, but cell subpopulation percentages were altered; the percentage of lymphocytes was significantly higher and monocytes significantly lower compared to both native CSF slides and FC. The percentage of granulocytes was higher in FC compared to cytology. For leukocyte count, the following reference ranges were estimated for Fuchs-Rosenthal chamber (FR) counting and FC, respectively: leukocytes ≤4.7/μL and ≤2.5/μL, lymphocytes ≤4.1/μL and ≤1.8/μL, monocytes ≤1.2/μL and ≤0.9/μL, and granulocytes 0/μL and ≤0.2/μL. The following reference ranges were estimated for basic subpopulations: T-lymphocytes 84.1 - 100%, B lymphocytes 0.0 - 1.5%, NK cells 0.0 - 6.3%, NKT cells 0 - 9.5%, and CD3+CD4+/CD3+CD8+ 0.8 - 4.9. Using a volume of 1.2-2.4 mL, the number of B lymphocytes was too low (<20) in samples with ≤2.7 cells/μL in the FR.

CONCLUSIONS

Even normal CSF samples are amenable to basic mononuclear cell subpopulation analysis by FC. However, analysis of the B-cell subpopulations requires either a larger sample volume or selection of samples with ≥ 3 cells/μL.

Application of flow cytometry in the analysis of lymphoid disease in the lung and pleural space

Various types of lymphoid neoplasms can occur in the lung. Lung parenchyma, the pleura or the pleural cavity can be the primary site of a lymphoid neoplasm or can be involved secondarily as a result of systemic dissemination from a separate primary site. Recognition of pulmonary lymphoid neoplasms (PLN) has increased secondary to technological advances in the medical field. Multiparameter flow cytometry (FC) is a one of the diagnostic tools that serves an essential role in the detecting and categorizing PLNs. FC allows for rapid identification and immunophenotypic characterization of PLN. In this article, we discuss the role of FC in the diagnosis of the most commonly encountered PLNs as well as their basic clinicopathologic features. We briefly discuss the role of FC in identifying non-hematolymphoid neoplasms in lung specimens as well.

Combined cellular and soluble mediator analysis for improved diagnosis of vitreoretinal lymphoma

Purpose

Primary vitreoretinal lymphoma [(P)VRL]) is a rare malignancy of the eye localized in the retina, vitreous or choroid. Here, we aim to determine the value of the combination of innovative diagnostic methods for accurate differentiation between (P)VRL and non‐(P)VRL in patients with suspect uveitis or vitritis.

Methods

Multicolour flow cytometric immunophenotyping of cells in the vitreous samples was performed using the EuroFlow small sample tube. Additionally, cytokines/chemokines and growth factors were measured in the vitreous specimens using a multiplex immunoassay. Data were evaluated in predefined clinical subgroups using omniviz unsupervised Pearson's correlation visualization and unsupervised heatmap analysis.

Results

A total of 53 patients were prospectively included in the period 2012–2015. In the (P)VRL subgroup (n = 10), nine cases showed aberrant surface membrane immunoglobulin (SmIg) light chain expression. In the non‐(P)VRL group (n = 43) clearly skewed SmIg light chain expression was observed in two multiple sclerosis‐related uveitis cases, but not in other uveitis types. Soluble mediator measurement revealed high interleukin (IL)‐10/IL‐6 ratios, and high IL‐1RA levels in 9/10 (P)VRL cases, but not in any non‐(P)VRL case. Further correlation and heatmap analysis revealed a minimal signature of cellular parameters (CD19+ B cells, aberrant SmIg light chain expression) and cytokine parameters (IL‐10/IL‐6 ratio >1, high IL‐10, high IL‐1 RA, high monocyte chemotactic protein‐1, high macrophage inflammatory protein‐1β) to reliably distinguish (P)VRL from non‐(P)VRL.

Conclusion

Here, we show the power of a combined cellular and proteomics strategy for detecting (P)VRL in vitreous specimens, especially in cases with minor cellular (P)VRL infiltrates.

Flow cytometry shows added value in diagnosing lymphoma in brain biopsies

Background

To assess the sensitivity, specificity and turnaround time of flow cytometric analysis on brain biopsies compared to histology plus immunohistochemistry analysis in tumors with clinical suspicion of lymphoma.

Methods

All brain biopsies performed between 2010 and 2015 at our institution and analyzed by both immunohistochemistry and flow cytometry were included in this retrospective study. Immunohistochemistry was considered the gold standard.

Results

In a total of 77 biopsies from 71 patients, 49 lymphomas were diagnosed by immunohistochemistry, flow cytometry results were concordant in 71 biopsies (92.2%). We found a specificity and sensitivity of flow cytometry of 100% and 87.8%, respectively. The time between the biopsy and reporting the result (turnaround time) was significantly shorter for flow cytometry, compared to immunohistochemistry (median: 1 vs. 5 days).

Conclusions

Flow cytometry has a high specificity and can confirm the diagnosis of a lymphoma significantly faster than immunohistochemistry. This allows for rapid initiation of treatment in this highly aggressive tumor. However, since its sensitivity is less than 100%, we recommend to perform histology plus immunohistochemistry in parallel to flow cytometry. © 2018 The Authors. Cytometry Part B: Clinical Cytometry published by Wiley Periodicals, Inc. on behalf of International Clinical Cytometry Society

Diagnostic markers for CNS lymphoma in blood and cerebrospinal fluid: a systematic review

Diagnosing central nervous system (CNS) lymphoma remains a challenge. Most patients have to undergo brain biopsy to obtain tissue for diagnosis, with associated risks of serious complications. Diagnostic markers in blood or cerebrospinal fluid (CSF) could facilitate early diagnosis with low complication rates. We performed a systematic literature search for studies on markers in blood or cerebrospinal fluid for the diagnosis CNS lymphoma and assessed the methodological quality of studies with the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS‐2). We evaluated diagnostic value of the markers at a given threshold, as well as differences between mean or median levels in patients versus control groups. Twenty‐five studies were included, reporting diagnostic value for 18 markers in CSF (microRNAs ‐21, ‐19b, and ‐92a, RNU2‐1f, CXCL13, interleukins ‐6, ‐8, and ‐10, soluble interleukin‐2‐receptor, soluble CD19, soluble CD27, tumour necrosis factor‐alfa, beta‐2‐microglobulin, antithrombin III, soluble transmembrane activator and calcium modulator and cyclophilin ligand interactor, soluble B cell maturation antigen, neopterin and osteopontin) and three markers in blood (microRNA‐21 soluble CD27, and beta‐2‐microglobulin). All studies were at considerable risk of bias and there were concerns regarding the applicability of 15 studies. CXCL‐13, beta‐2‐microglobulin and neopterin have the highest potential in diagnosing CNS lymphoma, but further study is still needed before they can be used in clinical practice.