Aug
13
Tue
2013
Plenary Address: Making sense of pathogen sensors of Innate Immunity: Utility of their ligands as antiviral agens and adjuvants for vaccines. @ Acharya Hall
Aug 13 @ 9:17 am – 9:55 am

SuryaprakashSuryaprakash Sambhara, DVM, Ph.D
Chief, Immunology Section, Influenza Division, CDC, Atlanta, USA


Making sense of pathogen sensors of Innate Immunity: Utility of their ligands as antiviral agents and adjuvants for vaccines.

Currently used antiviral agents act by inhibiting viral entry, replication, or release of viral progeny.  However, recent emergence of drug-resistant viruses has become a major public health concern as it is limiting our ability to prevent and treat viral diseases.  Furthermore, very few antiviral agents with novel modes of action are currently in development.  It is well established that the innate immune system is the first line of defense against invading pathogens.  The recognition of diverse pathogen-associated molecular patterns (PAMPs) is accomplished by several classes of pattern recognition receptors (PRRs) and the ligand/receptor interactions trigger an effective innate antiviral response.  In the past several years, remarkable progress has been made towards understanding both the structural and functional nature of PAMPs and PRRs.  As a result of their indispensable role in virus infection, these ligands have become potential pharmacological agents against viral infections.  Since their pathways of action are evolutionarily conserved, the likelihood of viruses developing resistance to PRR activation is diminished.  I will discuss the recent developments investigating the potential utility of the ligands of innate immune receptors as antiviral agents and molecular adjuvants for vaccines.

Suryaprakash (1) Suryaprakash (4) Suryaprakash-Nagaraja

Invited Talk: The system of PAS proteins (HIF and AhR) as an interface between environment and skin homeostasis @ Acharya Hall
Aug 13 @ 2:33 pm – 2:50 pm

andreyAndrey Panteleyev, Ph.D.
Vice Chair, Division of Molecular Biology, NBICS Centre-Kurchatov Institute, Moscow, Russia


The system of PAS proteins (HIF and AhR) as an interface between environment and skin homeostasis

Regulation of normal skin functions as well as etiology of many skin diseases are both tightly linked to the environmental impact. Nevertheless, molecular aspects of skin-environment communication and mechanisms coordinating skin response to a plurality of environmental stressors remain poorly understood.

Our studies along with the work of other groups have identified the family of PAS dimeric transcription factors as an essential sensory and regulatory component of communication between skin and the environment. This protein family comprises a number of hypoxia-induced factors (HIF-alpha proteins), aryl hydrocarbon receptor (AhR), AhR nuclear translocator (ARNT), and several proteins implicated in control of rhythmic processes (Clock, Period, and Bmal proteins). Together, various PAS proteins (and first of all ARNT – as the central dimerization partner in the family) control such pivotal aspects of cell physiology as drug/xenobiotic metabolism, hypoxic and UV light response, ROS activity, pathogen defense, overall energy balance and breathing pathways.

In his presentation Dr. Panteleyev will focus on the role of ARNT activity and local hypoxia in control of keratinocyte differentiation and cornification. His recent work revealed that ARNT negatively regulates expression of late differentiation genes through modulation of amphiregulin expression and downstream alterations in activity of EGFR pathway. All these effects are highly dependent on epigenetic mechanisms such as histone deacetylation. Characterisation of hypoxia as a key microenvironmental factor in the skin and the role of HIF pathway in control of dermal vasculature and epidermal functions is another major focus of Dr. Panteleyev’s presentation.

In general, the studies of Dr. Panteleyev’s laboratory provide an insight into the PAS-dependent maintenance of skin homeostasis and point to the potential role of these proteins in pathogenesis of environmentally-modulated skin diseases such as barrier defects, desquamation abnormalities, psoriasis, etc.

 

Aug
14
Wed
2013
Invited Talk: Electrospray ionization ion trap mass spectrometry for cyclic peptide characterization @ Amriteshwari Hall
Aug 14 @ 12:14 pm – 12:43 pm

SudarslalSudarslal S, Ph.D.
Associate Professor, School of Biotechnology, Amrita University


Electrospray ionization ion trap mass spectrometry for cyclic peptide characterization

There has been considerable interest in the isolation and structural characterization of bioactive peptides produced by bacteria and fungi. Most of the peptides are cyclic depsipeptides characterized by the presence of lactone linkages and β-hydroxy fatty acids. Occurrence of microheterogeneity is another remarkable property of these peptides. Even if tandem mass spectrometers are good analytical tools to structurally characterize peptides and proteins, sequence analysis of cyclic peptides is often ambiguous due to the random ring opening of the peptides and subsequent generation of a set of linear precursor ions with the same m/z. Here we report combined use of chemical derivatization and multistage fragmentation capability of ion trap mass spectrometers to determine primary sequences of a series of closely related cyclic peptides.

Sudars (1) Sudars (2)

 

Delegate Talk: Bioanalytical Characterization of Therapeutic Proteins @ Amriteshwari Hall
Aug 14 @ 12:44 pm – 12:54 pm
Delegate Talk: Bioanalytical Characterization of Therapeutic Proteins @ Amriteshwari Hall | Vallikavu | Kerala | India

Ravindra Gudihal, Suresh Babu C V


Bioanalytical Characterization of Therapeutic Proteins

The characterization of therapeutic proteins such as monoclonal antibody (mAb) during different stages of manufacturing is crucial for timely and successful product release. Regulatory agencies require a variety of analytical technologies for comprehensive and efficient protein analysis. Electrophoresis-based techniques and liquid chromatography (LC) either standalone or coupled to mass spectrometry (MS) are at the forefront for the in-depth analysis of protein purity, isoforms, stability, aggregation, posttranslational modifications, PEGylation, etc. In this presentation, a combination of various chromatographic and electrophoretic techniques such as liquid-phase isoelectric focusing, microfluidic and capillary-based electrophoresis (CE), liquid chromatography (LC) and combinations of those with mass spectrometry techniques will be discussed. We present a workflow based approach to the analysis of therapeutic proteins. In successive steps critical parameters like purity, accurate mass, aggregation, peptide sequence, glycopeptide and glycan analysis are analyzed. In brief, the workflow involved proteolytic digestion of therapeutic protein for peptide mapping, N-Glycanase and chemical labeling reaction for glycan analysis, liquid-phase isoelectric focusing for enrichment of charge variants followed by a very detailed analysis using state of the art methods such as CE-MS and LC-MS. For the analysis of glycans, we use combinations of CE-MS and LC-MS to highlight the sweet spots of these techniques. CE-MS is found to be more useful in analysis of highly sialylated glycans (charged glycans) while nano LC-MS seems to be better adapted for analysis of neutral glycans. These two techniques can be used to get complementary data to profile all the glycans present in a given protein. In addition, microfluidic electrophoresis was used as a QC tool in initial screening for product purity, analysis of papain digestion fragments of mAb, protein PEGylation products, etc. The described workflow involves multiple platforms, provides an end to end solution for comprehensive protein characterization and aims at reducing the total product development time.