CD2-SLFA3/T11TS interaction facilitates immune activation and glioma regression by apoptosis.
OBJECTIVE
Exogenous application of T11TS/SLFA3 in glioma model had shown the regression of tumor load through immunopotentiation. The mechanistic module of this interaction on immunological synapse formation and resulting effect in glioma regression is searched for delineating immunotherapeutic efficacy of T11TS.


METHODS
After purification of T11TS/SLFA3 from sheep erythrocytes the glycoprotein was characterized by SDS-PAGE analysis and glycoprotein staining. The modulatory effect of T11TS application on glioma animals were studied by CD2 and MHC class II expression on peripheral lymphocytes, PMN, macrophages and intracranial microglia by flowcytometric analysis. Finally apoptotic killing of brain cells were studied through annevin-V expression and measuring fragmented cytoplasmic DNA by ELISA.


RESULTS
Compared to healthy normal counter-parts the CD2 receptor downregulation by ENU treatment in lymphocytes and PMN were upregulated with three consecutive doses of T11TS. Splenic antigen presenting macrophages and intracranial mocroglia had shown CD2 and MHC class II modulation simultaneously in their different subtypes. These receptor studies revealed significant boosting of the immune competent cells most effectively in second dose of T11TS whereas the third dose had some regulatory effect. Sharp increase of apoptosis in brain cells was found by phosphatidylserine externalization and presence of fragmented DNA in cytoplasm with application of T11TS in consecutive doses as a result of immune potentiation.


CONCLUSIONS
Receptor studies revealed modulation of CD2 and MHC class II, two important constituents of immunological synapse successfully help to form the TCR-p-MHC complex and provide required co-stimulation for activation. Potentiated immune effector machinery was then directed to abrogate glioma by apoptosis signifying T11TS as an immunotherapeutic probe.
Sarkar
Susobhan
S
Cellular and Molecular Immunology Lab, Department of Physiology, Dr. B.C. Roy Institute of Basic Medical Sciences, Institute of Post Graduate Medical Education and Research (IPGME&R) Kolkata 700020, India.
Ghosh
Anirban
A
Mukherjee
Joydeep
J
Chaudhuri
Samares
S
Chaudhuri
Swapna
S
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001932:Brain Neoplasms / Q000188:drug therapy / Q000276:immunology* / Q000517:prevention & control; D018801:CD2 Antigens / Q000378:metabolism; D018968:CD58 Antigens / Q000302:isolation & purification / Q000378:metabolism* / Q000627:therapeutic use*; D004912:Erythrocytes / Q000166:cytology; D005038:Ethylnitrosourea / Q000633:toxicity; D005260:Female; D005434:Flow Cytometry; D005805:Genes, MHC Class I / Q000502:physiology; D005910:Glioma / Q000188:drug therapy / Q000276:immunology* / Q000517:prevention & control; D008214:Lymphocytes; D008264:Macrophages / Q000378:metabolism; D008297:Male; D017628:Microglia / Q000378:metabolism; D009153:Mutagens / Q000633:toxicity; D010718:Phosphatidylserines / Q000378:metabolism; D011485:Protein Binding; D051381:Rats; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D012397:Rosette Formation; D012756:Sheep
D018801:CD2 Antigens; D018968:CD58 Antigens; D009153:Mutagens; D010718:Phosphatidylserines; D011948:Receptors, Antigen, T-Cell; D005038:Ethylnitrosourea