Albumin enhanced morphometric image analysis in CLL

An early warning indicator of mortality risk in patients with COVID-19: the neutrophil extracellular traps/neutrophilic segmented granulocyte ratio

Background

Neutrophil extracellular traps (NETs) play a key role in thrombus formation in patients with coronavirus disease 2019 (COVID-19). However, the existing detection and observation methods for NETs are limited in their ability to provide quantitative, convenient, and accurate descriptions of in situ NETs. Therefore, establishing a quantitative description of the relationship between NETs and thrombosis remains a challenge.

Objective

We employed morphological observations of blood cells and statistical analyses to investigate the correlation between the NETs/neutrophilic segmented granulocyte ratio and mortality risk in patients with COVID-19.

Methods

Peripheral blood samples were collected from 117 hospitalized patients with COVID-19 between November 2022 and February 2023, and various blood cell parameters were measured. Two types of smudge cells were observed in the blood and counted: lymphatic and neutral smudge cells. Statistical data analysis was used to establish COVID-19 mortality risk assessment indicators.

Results

Morphological observations of neutrophilic smudge cells revealed swelling, eruption, and NETs formation in the neutrophil nuclei. Subsequently, the NETs/neutrophilic segmented granulocyte ratio (NNSR) was calculated. A high concentration of NETs poses a fatal risk for thrombus formation in patients. Statistical analysis indicated that a high NNSR was more suitable for evaluating the risk of death in patients with COVID-19 compared to elevated fibrinogen (FIB) and D-dimer (DD) levels.

Conclusion

Observing blood cell morphology is an effective method for the detection of NETs, NNSR are important markers for revealing the mortality risk of patients with COVID-19.

Impact on canine neutrophil preservation with the addition of bovine serum albumin to K3 -EDTA whole blood samples

BACKGROUND

Cellular deterioration occurs with blood sample aging, impacting white blood cell (WBC) identification and differential accuracy. This may be exacerbated in samples from patients experiencing inflammation. Previously, bovine serum albumin (BSA) has been shown to improve cellular preservation of blood and other samples, but the effect on cell preservation in canine blood has not been assessed.

OBJECTIVES

We aimed to determine the effects of BSA on neutrophil nuclear area when added to potassium ethylene diamine tetra-acetic acid (K3 -EDTA)-anticoagulated canine blood prior to blood smear preparation. We evaluated the impact of inflammatory leukograms, sample storage temperatures (4° and 20°C), and time on outcomes.

MATERIALS AND METHODS

Canine K3 -EDTA-anticoagulated blood samples stored at 4° and 20°C were used from unique patients, 10 with and 10 without inflammatory leukograms. Blood smears were prepared from aliquots with or without the addition of 22% BSA at 0, 4, 8, 24, 48, and 72 h. The nuclear area was measured for 25 randomly selected neutrophils per slide using Fiji software. Mixed-effect linear regression modeling was performed (significance: P < 0.05).

RESULTS

Nuclear area increased over time with and without added BSA. Both sample storage temperatures and the presence or absence of an inflammatory leukogram significantly impacted neutrophil nuclear area. Samples with added BSA had slightly higher predicted nuclear areas than those without BSA, but this difference was not statistically significant.

CONCLUSIONS

BSA did not significantly impact neutrophil nuclear area and did not improve neutrophil preservation in canine blood samples.

Death of tonsillar B cells by NETosis

Regulating B cell death is essential for generating antibodies and maintaining immune tolerance. B cells can die by apoptosis, and we report that human tonsil B cells, but not peripheral blood B cells also die by NETosis. This cell death is density-dependent, characterized by the loss of cell and nuclear membrane integrity, release of reactive oxygen species, and chromatin decondensation. Tonsil B cells secrete high levels of TNF, and inhibiting TNF prevented chromatin decondensation. By in situ fluorescence microscopy, B cell NETosis, as identified by the hyper citrullination of Histone-3, was localized to the light zone (LZ) of germinal centers in normal tonsil and overlapped with the B cell marker CD19/IgM. We propose a model in which stimulation of B cells in the LZ induces NETosis, driven in part by TNF. We also provide evidence that NETosis of tonsil B cells may be inhibited by an unidentified factor in tonsil. The results describe a previously unidentified form of B cell death and suggest a new mechanism to maintain B cell homeostasis during immune responses.

Smudge Cells in Chronic Lymphocytic Leukemia: Pathophysiology, Laboratory Considerations, and Clinical Significance

Chronic lymphocytic leukemia (CLL) is the most commonly encountered leukemia in the clinical laboratory. Cytoskeletal defects in CLL lymphocytes can result in the formation of up to 75% smudge cells (SCs) during blood film preparation. Failure to account for these damaged lymphocytes in the white blood cell (WBC) differential diminishes the accuracy and reproducibility of the results. Lacking clear practice standards on handling SCs in CLL, different laboratories may employ different methods to mitigate SC-induced errors. This review explores the pathophysiology of SCs, their effect on WBC differentials in CLL, and how these results can impact clinical decisions. The pros and cons of various SC corrective methods are described to assist laboratories in developing an optimized protocol to reduce errors and inconsistencies in WBC differentials. Finally, the potential utility of SC enumeration as an indicator of CLL prognosis is discussed in terms of laboratories with differing access to technology.

New quantitative features for the morphological differentiation of abnormal lymphoid cell images from peripheral blood

AIMS

This work aims to propose a set of quantitative features through digital image analysis for significant morphological qualitative features of different cells for an objective discrimination among reactive, abnormal and blast lymphoid cells.

METHODS

Abnormal lymphoid cells circulating in peripheral blood in chronic lymphocytic leukaemia, B-prolymphocytic leukaemia, hairy cell leukaemia, splenic marginal zone lymphoma, mantle cell lymphoma, follicular lymphoma, T-prolymphocytic leukaemia, T large granular lymphocytic leukaemia and Sézary syndrome, normal, reactive and blast lymphoid cells were included. From 325 patients, 12 574 cell images were obtained and 2676 features (27 geometric and 2649 related to colour and texture) were extracted and analysed.

RESULTS

We analysed the 20 most relevant features for the morphological differentiation of the 12 lymphoid cell groups under study. Most of them showed significant differences: 19 comparing follicular and mantle cells, 18 for blast and reactive cells, 17 for Sézary cells and T prolymphocytes and 16 for B and T prolymphocytes and 16 for villous lymphocytes. Moreover, a total of five quantitative features were significant for the discrimination among reactive and the set of abnormal lymphoid cells included.

CONCLUSIONS

Image analysis may assist in quantifying cell morphology turning qualitative data into quantitative values. New cytological variables were established based on geometric and colour/texture features to contribute to a more accurate and objective morphological assessment of lymphoid cells and their association with flow cytometry methods may be interesting to explore in the next future.

Leukocytosis

An increased white blood cell count, or leukocytosis, is a common laboratory finding. Appropriate specimen evaluation depends on which lineages are increased and the morphologic findings on peripheral blood smear review to guide further testing. The presence of blasts is concerning for acute leukemia and may require bone marrow biopsy. Lymphocytosis may be morphologically divided into polymorphic and monomorphic populations. Polymorphic lymphocytosis is most consistent with a reactive process, while monomorphic populations are concerning for lymphoproliferative neoplasm. The differential can be further narrowed based on morphologic findings. Myeloid leukocytosis can occur in a number of reactive conditions as well as myeloid malignancies. The types of cells present and morphology can help to guide additional workup. This study provides guidance for the appropriate evaluation and further workup of leukocytosis.

Protective effects of dietary antioxidants on proton total-body irradiation-mediated hematopoietic cell and animal survival

Abstract Dietary antioxidants have radioprotective effects after gamma-radiation exposure that limit hematopoietic cell depletion and improve animal survival. The purpose of this study was to determine whether a dietary supplement consisting of l-selenomethionine, vitamin C, vitamin E succinate, alpha-lipoic acid and N-acetyl cysteine could improve survival of mice after proton total-body irradiation (TBI). Antioxidants significantly increased 30-day survival of mice only when given after irradiation at a dose less than the calculated LD(50/30); for these data, the dose-modifying factor (DMF) was 1.6. Pretreatment of animals with antioxidants resulted in significantly higher serum total white blood cell, polymorphonuclear cell and lymphocyte cell counts at 4 h after 1 Gy but not 7.2 Gy proton TBI. Antioxidants significantly modulated plasma levels of the hematopoietic cytokines Flt-3L and TGFbeta1 and increased bone marrow cell counts and spleen mass after TBI. Maintenance of the antioxidant diet resulted in improved recovery of peripheral leukocytes and platelets after sublethal and potentially lethal TBI. Taken together, oral supplementation with antioxidants appears to be an effective approach for radioprotection of hematopoietic cells and improvement of animal survival after proton TBI.