title: Heteroglucan-dendrimer glycoconjugate: a modulated construct with augmented immune responses and signaling phenomena.
abstract: BACKGROUND
  Newer strategies for augmenting immune responses of pharmacologically active glucans may serve to improve the medicinal potential of these biomolecules. With this aim, the present work was focused on generating targeted high molecular size glucan particles with magnified immune response activity.
  
  
  METHODS
  Heteroglucans were conjugated with PAMAM dendrimers using a Schiff base reductive amination reaction to generate a polytethered molecule with multiple glucan motifs. The modulated construct was characterized by FTIR, TEM, (1)H NMR and dynamic light scattering (DLS) methods. Effects of conjugated glucans were examined in RAW 264.7 macrophage cells as well as in S-180 murine tumor models.
  
  
  RESULTS
  Dendrimer-conjugated glucans were found to exhibit a two-fold increase in immune stimulation in comparison to unconjugated glucans. This may be corroborated by the predominant enhancement in immunological functions such as nitric oxide production, ROS generation and immune directed tumor inhibition in murine models. Immune cell surface markers (CD4, CD8, CD19, MHC-II) and cytokine levels were also found to be highly up-regulated in the splenocytes of mice subjected to particulate glucan administration. Our study also demonstrated that conjugated glucan treatment to RAW 264.7 cells strongly enhanced the phosphorylation of two downstream signalling molecules of the mitogen activated protein kinase (MAPKs) family: p38 and MEK1/2 relative to single glucans thereby relating molecular mechanisms with enhanced immune stimulation.
  
  
  CONCLUSIONS
  The results obtained thus support that particulate format of soluble heteroglucan will thereby improve its functionality and identify leads in therapeutic competence.
authors.affiliation: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
authors.forename: K Sanjana P
authors.initials: KS
authors.lastname: Devi
authors.affiliation: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
authors.forename: Birendra
authors.initials: B
authors.lastname: Behera
authors.affiliation: Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
authors.forename: Banalata
authors.initials: B
authors.lastname: Sahoo
authors.affiliation: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India. Electronic address: tkmaiti@hijli.iitkgp.ernet.in.
authors.forename: Tapas K
authors.initials: TK
authors.lastname: Maiti
mesh_terms: D000276:Adjuvants, Immunologic / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D015703:Antigens, CD / Q000276:immunology; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology; D002460:Cell Line; D016207:Cytokines / Q000276:immunology; D050091:Dendrimers / Q000737:chemistry / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D008264:Macrophages / Q000166:cytology / Q000276:immunology*; D051379:Mice; D011134:Polysaccharides / Q000737:chemistry / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D015703:Antigens, CD; D001672:Biocompatible Materials; D016207:Cytokines; D050091:Dendrimers; D000949:Histocompatibility Antigens Class II; C104700:PAMAM Starburst; D011134:Polysaccharides; D017382:Reactive Oxygen Species; D048049:Extracellular Signal-Regulated MAP Kinases
keywords: Biomolecules; Dendrimer conjugated heteroglucan; Immune stimulation; Signalling; Therapeutic; Tumor inhibition