Biomedical subjects

Zarina Begum

Publications and source records attributed to Zarina Begum.

5 recordsLinked to original sources

PubMed2005

Sheep erythrocyte demonstrated better effect than IL-2 and IFN-gamma as biological response modifier against glioma in experimental model.

The significant insights into the immunobiology of central nervous system (CNS) and brain tumor have opened up the feasibility of applying 'Immunotherapy' as an alternative to the poor prognosis of malignant brain tumor with conventional therapeutic approaches. Though cytokines like IL-2 and IFN-gamma used against glioma showed some favorable results by eliciting Th1 type immune response, a proper immunotherapeutic agent is still to be searched for. Sheep erythrocyte (SRBC), a corpuscular antigen showed a better therapeutic efficacy in terms of enhanced survival and augmentation of cell mediated immunity (CMI) in a glioma model developed by chemical carcinogen ethyl nitrosourea. Histological findings revealed most efficient glioma rejection in SRBC and combination biological response modifier (BRM) treated groups. Simultaneously E-rosetting, cytotoxicity of lymphocytes, phagocytosis and antigen presenting capacity of myeloid cells established the better therapeutic efficacy of SRBC alone than other BRMs viz. IL-2 and IFN-gamma. Even the effect of combination therapy of different BRMs showed marginal differences in facilitating glioma reduction than the single use of SRBC. These findings emphasized the application of SRBC as an exogenous BRM having the potential as a rational therapeutic adjunct against glioma.

Animals↗

PubMed2003

Brain tumor inhibition in experimental model by restorative immunotherapy with a corpuscular antigen.

In view of the advances in our understanding of anti-tumor immune response, it is now tempting to contemplate the development of immunotherapies for malignant brain tumors, for which no effective treatment exists. Immunotherapy, with agents known as biological response modifiers (BRMs) are thus gaining increasing interest as the fourth modality of treatment. A non-specific BRM, sheep erythrocytes (SRBC) when administered (ip, 7% PCV/V, 0.5 ml) in a group of animals at the end of seventh month of ethylnitrosourea administration, resulted in significant increase in the mean survival time (> 350 days). Studies conducted for growth kinetics pattern with proliferation index and fluorochrome (HO-33342) uptake techniques at the tissue culture level exhibited a regulatory inhibition of the cells isolated from tissue excised from the tumor susceptible area of brain of SRBC treated animals. Moreover, histological examination of brain from animals showed immunomodulatory role of SRBC in experimentally induced brain tumor. Further probe into the mechanisms involving immunological investigations at the cellular level in these animals indicated an augmented and potentiated cell mediated immune response (CMI) as evidenced by enhanced spontaneous rosette forming capacity and cytotoxic activity of lymphocytes and neutrophil (PMN) mediated phagocytosis respectively. The observations suggest that SRBC down regulate malignant growth pattern of experimental brain tumors either by an immunologically enhanced killing of tumor cells and/or by directly inhibiting the tumor growth possibly via a stimulated cytokine network. Thus, a corpuscular antigen, can potentiate CMI response in experimentally induced brain tumor animal model, in which response induced in the periphery are able to mediate anti-tumor effects in the brain.

Adjuvants, Immunologic↗

PubMed2002

Preclinical Changes in Immunoreactivity and Cellular Architecture during the Progressive Development of Intracranial Neoplasms and an Immunotherapeutic Schedule with a Novel Biological Response Modifier, the T11TS / S-LFA3.

Among neoplasms, brain tumors are particularly " difficult to treat" because of the partial immune privileged status of the brain and the presence of the blood brain barrier (Selmaj, 1996). Many details of progressive development of brain tumors remain unexplored and elucidation of consequent changes of the immune system with correlated cellular architecture and cell kinetics were the major objectives of the present course of investigations. Our studies have indicated that the primary resistance by the immune system to a growing tumor declines after a certain point, resulting in an immune suppressed state in a tumor bearing individual. The poor prognosis of malignant brain tumors with classical treatments like surgery, radiotherapy and chemotherapy has led to interest in immunotherapeutic protocols. In the present study, an attempt was made to determine the immunomodulatory and antitumor properties of a transmembrane glycopeptide of sheep red blood cells (SRBCs), known as S-LFA3 or T11TS. Young Druckray rat of both sexes aged 3-5 days were injected with N'-N'-ethyl nitrosourea (ENU) (i.p) to induce brain tumors and at 2,4,6,8 and 10 months of age were sacrificed for study of survival, tumor growth kinetics and immunological parameters like lymphocyte rosette formation, denoting CD2 - CD58 interactions and phagocytosis by peripheral macrophages and PMN hint at the changes during tumore development. In order to determine the immunomodulatory role of T11TS, 7 month old ENU induced animals and controls were injected with the compound (1 ml., i.p). The data obtained indicate that administration of T11TS results in increased survival of rats along with a decrease in growth kinetics of tumor cells to the normal level when compared to ENU induced animals of the same age. Pointers to mechanisms involving immunological investigations at the cellular level in these animals indicated improved lymphocyte function in terms of E-rosetting, augmented cytotoxicity and enhanced PMN and macrophage function in terms of phagocytosis. Finally histological examination showed complete reversal from the hyperplastic state to normal cellular homeostasis, indicating antitumor efficacy of T11TS, correlating very well with the data from survival and cell kinetic studies.

Journal Article↗

PubMedDate not supplied

Evaluation of anti-tumor property of specific and non-specific BRMs in experimental gioma by assessing the microglial cell functional and phenotypic modulations.

BACKGROUND: Microglial cells are considered to be the chief immunomodulatory cells of the brain. These cells play a crucial role against various neurodegenerative diseases. When modulated microglia have been shown to exert a potential anti-tumor immune response against brain neoplasms. Although several specific BRMs like IL-2, IFNgamma have been shown to modulate the microglia to get an effective anti-tumor immune response, associated toxicities and detrimental side effects have posed severe limitation in there use particularly for therapeutic purposes. OBJECTIVES: In the present study, attempts have been made to elicit the modulations of microglia cell function and phenotypic expression following specific (IL-2, IFNgamma and a novel nonspecific BRM (corpuscular antigen) in order to determine their anti-tumor property in experimental glioma model. MATERIALS AND METHODS: Brain was experimentally induced in young Druckray rats of both sexes with N-N-ethyl nitroso urea (ENU). These ENU treated animals were administered with both specific and nonspecific BRMs like IL-2, IFNgamma and SRBC either singly or in combination 5 months after ENU administration and after ascertaining its degree of malignancy. RESULTS: Microglial cells separated from different experimental groups were found to be positive for CD11b, MHC II, CD4 and negative for GFAP.FACS analysis demonstrated that different subtypes of microglial cell populations (CD25+, MHC II+ and CD25+MHC II+) in the brain tissue based on phenotypic expression, which were downregulated in tumor bearing animals, and subsequently restored with increased expression, particularly with SRBC administration. The Scanning Electron Microscopic (SEM) study also depicted modulation of cellular morphology of microglial cell predominantly with SRBC administration. Studies conducted ton evaluate immunological functions at the cellular level showed increased antigen presenting caopacity of microglial cell with SRBC administration, which was significantly greater then IL-2, IFNgamma and combined doses (E2_S). However phagocytic functions of microglial cells were found not to be significantly modulated with BRM treatment. CONCLUSION: The results suggest that the nonspecific BRM SRBC can exert greater modulatory effect on microglila cell function and phenotypic expression than the other BRMs used, and in doing so culminate in a potent anti tumor immune response in experimental glioma with compatible tolerance profile.

Animals↗

PubMedDate not supplied

The first cross sectional survey on intracranial malignancy in Kolkata, India: reflection of the state of the art in southern West Bengal.

Recent increase in the occurrence of intracranial malignancies and poor performance of therapeutic measures have established the disease as an important concern of medical sciences. The lack of information about the disease pattern throughout India creates problems for maintaining community health for prevention. The present study on the hospital population of Kolkata was conducted to determine the incidence pattern of the disease in the population of southern West Bengal, focusing on distribution with age, sex, occupation and religion in different districts of the region, and characterizing diagnostic and therapeutic measures. Among a total of 39,509 cancer patients from 21 health centers of Kolkata, 2.4% had brain cancers and among these more than 60% are gliomas. A cross-sectional study for a period of 3 years reported the occurrence of 15 types of intracranial malignancy, which demonstrated astrocytomas (36.8%), glioblastoma multiforme (GBM) (7.9%) and meningiomas (11.6%) to be predominant. Brain tumors occur more frequently in males with few exceptions and the incidence was found to be highest among the 40-49 year old group (20.2%). No specific trend for religion and occupation was apparent. However, the district wise distribution showed maximum incidences among industrial areas, namely, Kolkata (33.1%), North 24-Parganas (18.2%), Howrah (9.3%) and Hoogly (7.6%). Diagnosis of the disease was by CT scan, MRI and histological identification (pre and post operative). Therapeutic procedures rely mainly on surgery and radiotherapy, whereas chemotherapy was used as an adjuvant for about 10% of the cases. Evaluation of the scenario regarding intracranial malignancy in this region was a long awaited requirement which should ultimately serve an important function in pointing to risk zones within the population and allow better control measures to be introduced for the disease.

Adolescent↗