Immunocytotoxic Effect of Aqueous Leaf Extract of Cassia occidentalis on Human Peripheral Blood Mononuclear Cells and Neutrophils

Abstract

The study evaluates the potential immunocytotoxic effect of aqueous leaf extract of Cassia occidentalis on human peripheral blood mononuclear cells (PBMCs) and Neutrophils. Different concentrations (25 µg/ml, 50 µg/ml, 100 µg/ml) of the extract were prepared. Six millilitres (6ml) of peripheral blood from consented healthy volunteers was collected and PBMCs and neutrophils were isolated on Histopaque media. The viability of PBMCs and neutrophils was determined using trypan blue dye exclusion methods. One-way analysis of variance was used in analysing the results. Total viable cell count (TVCC) for PBMCs and neutrophils yielded 298.9 x 104 cells/ml and 327.9 x 104 cells/ml respectively. The TVCC of the highest concentration (100 µg/ml) of the extract used for the treatment of PBMCs was 192.7 x104 cells/ml and that of neutrophil was 50.47 x104 cells/ml equivalent to 82.51% and 61.71% mean viability percentages respectively. The PBMCs and neutrophils treated with 25 µg /ml of the extract have the highest mean percentage viability scores of 94.88% and 74.61% respectively. There was a significant difference in the mean percentage viability when control PBMCs was compared with those treated with 100 µg/ml (p<0.0001) and also when control neutrophils was compared with those treated with 25 µg /ml (p=0 .02), 50 µg /ml and 100 µg /ml (p<0.0001) respectively. The cell viability tends to decrease in a dose-dependent manner. The aqueous leaf extract of C. occidentalis has a potent cytotoxic effect on both cells, especially at a higher dose. The study recommends an in-depth study to improve the credence of the present study findings. Keywords: Cassia occidentalis extract, Cytotoxic activity, Human Neutrophils and PBMCs

In-Vitro Cytotoxic and Proliferative Activity of Three Plant Extract on Human Peripheral Blood Mononuclear Cells (PBMCs)

“…In comparison, most of the lower concentrations of the extracts had a very low cytotoxic effect on the PBMCs, which could be attributed to the low dosage of the extracts, which may contain a lower amount of cytotoxic phytochemicals and thus do not significantly impair cell viability. This finding is consistent with previous research that found a dose-dependent decrease in PBMC viability when exposed to Cassia occidentalis (Hamid et al, 2021), Vitellaria paradoxa (Kalgo et al, 2020), Annona squamosa, Datura metel, and Mentha piperita (Sudeep et al, 2017) plants extracts. At the lowest concentration tested (25 g/ml), LAASF had the least cytotoxic effect on PBMCs, while MI had the highest cytotoxicity at the highest concentration tested (200 g/ml).…”

“…Three millilitres (3 ml) of whole blood was collected using Monovette vacutainer system from apparently healthy volunteer that consented to participate in the study. The sample collected was transferred into a labelled lithium heparin tube, mixed properly and used for isolation of human PBMCs (Hamid et al, 2021).…”

“…The PBMCs were isolated using Histopaque-1077 (Sigma-Aldrich ® Co. UK) as described in Hamid et al (2021). Briefly, three millilitres (3 ml) of Histopaque-1077 was added to a 15 ml centrifuge tube and brought to room temperature.…”

“…The PBMCs isolated were counted using trypan blue assay as described in Hamid et al (2021). Briefly, ten microliters (10 µl) of 0.4% Trypan Blue (Sigma-Aldrich ® Co. United Kingdom) solution (w/v) and 10 µl of the PBMCs suspension were transferred into a cryovials tube (dilution factor = 2) and mixed, it was then allowed to stand for maximum of 5 min.…”

“…The PBMC is made up of majorly lymphocytes (T cells, B cells, and natural killer [NK] cells), followed by monocytes/macrophages and dendritic cells. These cells work together to form an indispensable army of host defenses (Hamid et al, 2021). The PBMCs are commonly isolated from whole blood using the Ficoll-Paque density centrifugation method.…”