Study of the haematopoietic and immune effect of microalgae extracts

Microalgae, as a source of numerous biologically active substances, are promising candidates for the development of novel biologically active supplements. An important aspect determining the possibility of using microalgae involves the absence of adverse effects on the organs and systems of the human and animal body. At the development stage, special attention should be paid to the safety of microalgae for biomedical use in terms of the absence of significant negative effects on the haematopoiesis and the functional status of immune cells. In this regard, the present study investigates the effect of oil extracts obtained from five microalgae species on haematopoietic parameters, the number and functional activity of spleen and thymus cells, as well as on immunoglobulin levels in the blood serum of laboratory animals. According to the obtained results, Chlorella vulgaris (C. vulgaris) and Cylindrotheca closterium (C. closterium) extracts decrease the number of leukocytes in the peripheral blood. Coelastrella sp., C. closterium, and Porphyridium purpureum (P. purpureum) increase the proportion of neutrophils. P. purpureum was found to initiate an increase in the proportion of eosinophils. Arthrospira (Spirulina) platensis (A. platensis) and C. closterium produce a decrease in the proportion of monocytes. C. closterium and P. purpureum induce a reduction in the proportion of lymphocytes in the peripheral blood of laboratory mice. All microalgae extracts had no effect on erythropoiesis and haemoglobin. In addition, all microalgae extracts were found to reduce splenocyte proliferation, while their effect on thymocyte proliferation depended on the microalgae type. In the mice serum, Coelastrella sp. microalgae extract increases IgG levels, while P. purpureum and C. vulgaris decrease IgM and IgA levels, respectively.