Cytotoxic activity of T lymphocytes is induced upon stimulation with IL-3 plus GM-CSF in animal leukemia model

Characterizing the BCR repertoire during lymphocyte reduction and recovery mediated by cyclophosphamide and granulocyte-macrophage colony-stimulating factor

Leukopenia is a common manifestation of many diseases, including global outbreak SAS-CoV-2 infection. Granulocyte-macrophage colony-stimulating factor (GM -CSF) has been proved to be effective in promoting lymphocyte regeneration, but adverse immunological effects have also emerged. This study aim to investigate the effect of GM -CSF on BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration. Cyclophosphamide (CTX) and GM -CSF were used to inhibit and stimulate bone marrow hematopoiesis, respectively. High throughput sequencing was applied to detect the characteristics of BCR CDR3 repertoire in controls, CTX group and GM -CSF group. The white blood cells (WBCs) were quickly reduced (P < 0.05) with lymphocytes decreasing causing by CTX, and the WBCs and lymphocytes returned to the level of controls after GM -CSF treatment. The diversity of BCR heavy chain CDR3 repertoire was also significantly decreased in CTX group. Although there is still a big gap from the controls, the diversity was picked up after GM -CSF treatment. The expression of IGHD01-01, IGHD02-14 and IGHJ04-01 with high-frequency usage regularly and significantly changed in three groups, and many genes with low-frequency usage lost in CTX group and did not reappear in GM -CSF group. Moreover, two shared sequences and accounted for the highest proportion in GM -CSF group have been detected in animal model of chronic lymphocytic leukemia. These results revealed that GM -CSF can partially restore changes in the BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration, but it may also lead to rearrangement, proliferation and activation of abnormal B cells, which can provide a basis for further study on the adverse immunological effects and mechanism of GM -CSF treatment.

IL-27 along with IL-28B ameliorates the pulmonary redox impairment, inflammation and immunosuppression in benzo(a)pyrene induced lung cancer bearing mice

AIMS

The major cause behind lung cancer development is exposure to various polycyclic aromatic hydrocarbons like benzo(a)pyrene (BaP) present in tobacco smoke, motor vehicle, and industrial exhaust. BaP is reported to induce the expression of various pro-inflammatory cytokines and matrix remodeling proteins. It is also responsible for dysfunction and exhaustion of the killing capacity of CD8+ T lymphocytes, one of the important components of the immune system which can kill tumor cells. We tried to evaluate the synergistic role of IL-27 and IL-28B in modulation of BaP-induced lung carcinogenesis associated with various hallmarks like pulmonary redox imbalance, angiogenesis, inflammation and cell proliferation in lung tissue.

MAIN METHOD

BaP was treated to Swiss albino mice to develop lung tumor. After the confirmation of lung tumor development Swiss albino mice were treated with IL-27 and IL-28B alone or in combination intraperitoneally. Histological analysis, immunohistochemistry, biochemical assay, western blot analysis, cell cytotoxicity assay, real-time PCR assay etc. were performed to evaluate the modulatory role of IL-27 and IL-28B.

KEY FINDINGS

We observed that IL-27 and IL-28B were able to suppress the expression of lung cancer-associated NFkB, COX-2, and iNOS. The expression of TNF-α, PCNA and some matrix remodeling enzymes were also modulated upon IL-27 and IL-28B treatment. Although the population of lung residing CD8+ T cells in tumor bearing lung tissue were unresponsive but the activity of systemic CD8+ cells was increased.

SIGNIFICANCE

Results hinted that IL-27 along with IL-28B were able to ameliorate various hallmarks ranging from angiogenesis to inflammation associated with the BaP-induced lung carcinogenesis. From this study, we propose that IL-27 and IL28B can be used as immunotherapeutic agent to regulate lung cancer.

Application of either nano fibrillated cellulose methotrexate or nano silicon dioxide methotrexate composites against renal fibrosis in leukemia rat model

Cellulose derivatives have got growing interest due to their relative abundance and ability to sustain the release of medicaments. In this study, micro- and nano-fibrillated cellulose were prepared from rice straw and used as drug carriers. Both carriers in addition to another one which is nano silicon dioxide were characterized with various techniques. Methotrexate was chosen to be loaded on nano-fibrillated cellulose and nano silicon dioxide. Both methotrexate carriers were evaluated for their possible protective role against renal fibrosis induced by methotrexate in leukemia rat model. Results of this study exhibited that loading methotrexate on either nano-fibrillated cellulose or nano silicon dioxide seems to have an ameliorative role on renal function tests, inflammatory and fibrotic markers of renal tissues. Moreover, the sustained release of methotrexate for long time period maintained by nano-fibrillated cellulose carrier gives it more priority than nano silicon dioxide to be used as an effective novel drug carrier in further medical applications with minimal side effects on kidney tissue in leukemia model.

IL-15 and GM-CSF stimulated macrophages enhances phagocytic activity in ENU induced leukemic mice

Murine splenic macrophage plays a decisive role in host immunity through phagocytosis against pathogens. It was reported that, macrophages also involves in phagocytosis of some tumour cells upon its activation initiated by certain cytokines produced by other immune cell or by indigenously treated. In this study, we have investigated the killing of leukemic blast cells by macrophages upon stimulated with IL-15 and GM-CSF alone or in combination in ENU challenged leukemic murine model. Along with, the release of TNF-α, IL-12 and IFN-γ by macrophages were assayed by ELISA. NO production by macrophages was also investigated. The molecular expressions like GM-CSF and TLRs were investigated for better understand of macrophage-leukemic cell interaction. Result shows that in disease condition macrophages have poor phagocytic activities which may be due to less release of TNF-α, IL-12 and IFN-γ by macrophages. This impaired phagocytic activity in leukemic mice was increase upon stimulation with IL-15 and GM-CSF.

Bromelain plus peroxidase reduces non-Hodgkin lymphoma progression in invivo via up-regulation of antioxidant enzymes and modulating apoptotic protein expression

Aim: Pineapple (Ananas comosus (L.) Merr.) is a good source of bromelain (B) and also contain peroxidase. The objective of this study is isoaltion of bromelain plus peroxidase (BP) from the pineapple fruit to evaluate the anticancer activity of BP from the pineapple fruit of Tripura, compared to commercial bromelain against ascitic Dalton's lymphoma cells (DLA) in mice. Methods: By acetone precipitation BP was isolated from the pineapple. Animals bearing DLA, receive B and BP orally for 15 alternative days. Apoptotic proteins are assayed using western blot. Results: BP treated mice showed recover of hemoglobin and WBC count compared to control lymphoma animal. The animal showed significant reduction of body weight due to reduced tunor load and elevated reactive oxygen species (ROS) production, elevated levels of vitamin C and vitamin E and other antioxidants in blood after BP treatment. Histology of liver and kidney also shows restored architecture in BP treated animal compared to only B treated group. BP treatment upregulates the cytochrome C, BAD, and BAX protein and downregulates the Bcl-2 and NF-kβ occuring upon BP treatment in the DLA cells collected from lymphoma animal. This induce the apoptosis of DLA cells in lymphoma animal and reduce the tumor load. Conclusion: The present findings suggest that BP from pineapple improves the survival of the induced lymphoma animal compared to only B which may be used as therapeutic target.

Hematopathological alterations of major tumor suppressor cascade, vital cell cycle inhibitors and hematopoietic niche components in experimental myelodysplasia

Myelodysplastic syndrome (MDS) is a poorly understood dreadful hematopoietic disorder that involves maturational defect and abnormalities in blood cell production leading to dysplastic changes and peripheral blood pancytopenia. The present work aims in establishing the mechanistic relationship of the expressional alterations of major tumor suppressor cascade, vital cell cycle inhibitors and hematopoietic microenvironmental components with the disease pathophysiologies. The study involves the development of N-N' Ethylnitrosourea (ENU) induced mouse model of MDS, characterization of the disease with blood film and bone marrow smear studies, scanning electron microscopic observation, mitochondrial membrane potential determination, flowcytometric analysis of osteoblastic and vascular niche components along with the expressional study of cleaved caspase-3, PCNA, Chk-2, p53, Ndn, Gfi-1, Tie-2, Sdf-1, Gsk-3β, p18 and Myt-1 in the bone marrow compartment. Dysplastic features were found in peripheral blood of MDS mice which seemed to be the consequence of three marrow pathophysiological conditions viz; aberrant rise of cellular proliferation, increased apoptosis and crowding of abnormal blast population. Expressional decline of the p53 cascade involving Chk-2, p53, Ndn, Gfi-1 along with the downregulation of major cell cycle inhibitors seemed to be associated with the hyper-proliferative nature of bone marrow cells during MDS. Moreover the disruption of osteoblastic niche components added to the decreased hematopoietic quiescency. Increased marrow vascular niche components signified the pre-malignant state of MDS. Elevated cellular apoptosis and rise in the blast burden were also found to be associated with the p53 expression dependent collapsing of mitochondrial membrane potential and upregulation of Tie-2 respectively. The study established the mechanistic correlation between the alterations of the mentioned signaling components and hematopoietic anomalies during MDS which may be beneficial for the development of therapeutic strategies for the disease.

Alteration of classical and hematopoiesis specific p53 pathway in the bone marrow hematopoietic stem/progenitor compartment facilitates leukemia progression in experimental mice

Downregulation of p53 is associated with most of the neoplasms, however it claims additional significance for hematopoietic malignancy due to its supplementary role during hematopoiesis. Apart from the classical role as tumor suppressor, p53 during steady state hematopoiesis is associated with the maintenance of quiescent cell population in bone marrow by upregulating necdin (Ndn) and Gfi-1. We felt, it is necessary to delineate its attribution towards malignant conversion of hematopoietic system during leukemogenesis from all the possible angles. The present study deals with the characterization of N-N' Ethylnitrosourea (ENU) induced mouse model of leukemia by peripheral blood hemogram, bone marrow cytology, histology, cytochemical staining (MPO) and scanning electron microscopic study. We further investigated the alteration of conventional and hematopoiesis specific p53 pathways by flowcytometric expressional analysis of ATM, Chk-2, p53, p21, Ndn, Gfi-1 and Tie-2. The disruption of classical p53 pathway was observed in leukemic hematopoietic stem/progenitor population which involved downregulation of ATM, Chk-2, p53 and p21. Moreover, the expressional decline of Ndn and Gfi-1 hinted towards the mechanism of hindrance of hematopoietic quiescency in leukemic bone marrow. Increased expression of Tie-2 due to reverse correlation with p53 was found to be responsible for pathological angiogenesis in bone marrow together with increased blast burden in bone marrow during leukemia. The study presents the mechanistic scenario of the alteration of both classical as well as hematopoiesis specific p53 pathways in HSPC compartment triggering leukemic pathophysiology.