Validation of Sysmex XT-2000iV generated quantitative bone marrow differential counts in untreated Wistar rats

Methodologies and Emerging Technologies for the Evaluation of the Hematopoietic System

Hematology and bone marrow analysis is central to our understanding of the hematopoietic system and how it responds to insults, and this session presented during the 2022 STP symposium provided a review of current and novel approaches for the evaluation of the hematopoietic system in the context of nonclinical investigations. This publication summarizes the information presented on novel approaches for evaluation of the hematopoietic system using automated hematology analyzers, including details around the quantitative assessment of bone marrow cell suspensions as well as introducing several newly available hematology parameters. It was followed by a discussion on intravital microscopy and live cell imaging and how these methods can assist with de-risking hematopoiesis-associated safety concerns, and a review of recent assays using artificial intelligence for the evaluation of bone marrow.

Opinion on the Optimal Histologic Evaluation of the Bone Marrow in Nonclinical Toxicity Studies

Identification of bone marrow toxicity is an important issue in drug development and toxicologic pathologists play a critical role in that identification. Knowledge of the general components of bone marrow, relevant anatomical and species differences, and the standard approach (routine systematic histological evaluation of the bone marrow in conjunction with analysis of the peripheral complete blood count data) will be reviewed. Specific morphologic features that anatomic pathologists should look for in the various components of bone marrow as well as suggested terminology for bone marrow findings will be discussed. Finally, an opinion on the limitations of the standard approach to bone marrow evaluation will be provided including general recommendations on when additional methods (image analysis of hematoxylin and eosin stained slides, flow cytometry or Sysmex XT 2000iV analysis, cytological evaluation of bone marrow smears, in vitro models, and transmission electron microscopy) might be useful in the detection or further characterization of bone marrow toxicity. [Box: see text].

Research-Relevant Clinical Pathology Resources: Emphasis on Mice, Rats, Rabbits, Dogs, Minipigs, and Non-Human Primates

Clinical pathology testing for investigative or biomedical research and for preclinical toxicity and safety assessment in laboratory animals is a distinct specialty requiring an understanding of species specific and other influential variables on results and interpretation. This review of clinical pathology principles and testing recommendations in laboratory animal species aims to provide a useful resource for researchers, veterinary specialists, toxicologists, and clinical or anatomic pathologists.

Reliable assessment of bone marrow and bone marrow concentrates using automated hematology analyzer

Aim: A limiting factor in advancement of bone marrow based cell therapies is the lack of characterization of cell products delivered to patients. Methods: Using an automated hematology analyzer that can be implemented in clinical setting, the composition of bone marrow aspirates (n = 17 patients) and bone marrow concentrates (n = 12 patients) were assessed. ICC estimates were calculated for measuring reliability. Results: Bone marrow aspirates assessment resulted in excellent reliability for determining white blood cells (ICC - 0.96; 95% CI: 0.92-0.99), red blood cells (ICC - 0.9; 95% CI: 0.77-0.96), platelets (ICC - 0.93; 95% CI: 0.85-0.97) composition. Bone marrow concentrate assessment resulted in excellent reliability for determining white blood cells (ICC - 0.97; 95% CI: 0.93-0.99), platelets (ICC - 0.95; 95% CI: 0.89-0.99) and moderate reliability for red blood cells (ICC - 0.66; 95% CI: 0.36-0.87) composition. Conclusion: Modern automated hematology analyzers could assist to better characterize the cell therapy products to provide reliable and consistent outcomes.

Hematologic and serum biochemical reference intervals of the Oriental white stork (Ciconia boyciana) and the application of an automatic hematologic analyzer

This study was conducted to establish accurate baseline values of clinical laboratory data with regard to age-related changes in the Oriental white stork (Ciconia boyciana). In addition, the availability of an automated hematological cell counter was evaluated. A total of 94 clinically normal storks, including 64 young storks (＜1 year old; 30 male and 34 female) and 30 adults (＞ 1 year old; 17 male and 13 female) were included. Hematological assays were performed using manual and automated cell counters and serum biochemistry profiles were examined using an automated analyzer. There were no significant differences in any parameters between male and female storks, while 16 parameters were significantly different between young and adult storks. Of these 16 parameters, total protein, albumin, aspartate aminotransferase, alanine aminotransferase, creatinine, triglyceride, total bilirubin, potassium, white blood cell count, packed cell volume, mean cell volume and hemoglobin levels were higher in adult storks than in young storks, while the latter showed higher glucose, uric acid and alkaline phosphatase levels, as well as a higher sodium/potassium ratio. The results presented herein will aid researchers who work for the conservation and rehabilitation of this endangered species.

Comparison of the Sysmex XT-2000iV with microscopic differential counts of canine bone marrow

Canine bone marrow is frequently assessed in the advanced preclinical research environment. Automated analysis provides time savings and objectivity over the gold standard of microscopic (cytologic) evaluation. We compared the analysis of 90 canine bone marrow samples by the Sysmex XT-2000iV hematology analyzer (Sysmex Corp., Kobe, Japan) with cytologic evaluation. Gates for cell populations were created in the system's WBC/BASO channel. Variables "total nucleated red blood cells" (total_NRBC), "poly- and orthochromatic nucleated red blood cells" (poly_orth_NRBC), "total neutrophils" (total_NEUT), "mature neutrophils" (mature_NEUT), and myeloid-to-erythroid (M:E) ratio were compared with cytologic evaluation. Intra-assay repeatability and total error (TE) were calculated for both methods. Intra-assay repeatability was 0.95-2.48% for the XT-2000iV and 8.32-23.23% for cytology. Observed TE for the automated measurement was 5.16-46.8% and for cytology 22.70-76.74%. Spearman rank correlation was excellent for M:E ratio (0.91) and fair for the other populations (0.65-0.71). Absolute bias for M:E ratio was low (-0.114). A negative absolute bias of -7.71% for the XT-2000iV was found for poly_orth_NRBC, whereas the bias was positive for total_NEUT (7.10%) and mature_NEUT (14.67%). M:E ratio of canine bone marrow samples can be precisely determined using the Sysmex XT-2000iV WBC/BASO channel. Total_NRBC, poly_orth_NRBC, total_NEUT, and mature_NEUT can be estimated rapidly. With distinctly lower coefficient of variation and observed TE compared with cytology, automated measurement provides advantages in terms of standardization, and it is suited to the advanced preclinical research environment where large numbers of samples are investigated.

Analysis of bone marrow aspiration fluid using automated blood cell counters

Cytomorphological examination of aspirate smears remains the basic method to diagnose hematologic disorders and to evaluate treatment-related changes. Last-generation hematological analyzers can count, besides cells normally circulating in peripheral blood, some types of immature and abnormal cells, such as erythroblasts and immature granulocytes. The complex nature of bone marrow fluid, however, has prevented until now the routine utilization of blood cell counters in this area. Recent studies have shown the possibility of using bone marrow fluid as a substitute for peripheral blood for clinical tests in particular situations and for repetitive cytologic examinations in specific clinical and research fields.