Our Services

 

i. Generation of Single Domain Heavy Chain Antibodies

In our experience with dromedary camels >75% of their immunoglobulins are antibodies devoid of light chains. These heavy-chain antibodies (HcAbs) interact with only one single variable domain. Despite the absence of light chain, these homodimeric antibodies exhibit a broad antigen-binding repertoire by enlarging their hypervarible regions. Our current research seeks to compare the properties of conventional and HcAbs targeting the same antigens and derived from the same animal in terms of specificity, affinity and sensitivity. Heterohybridoma technology is being explored to immortalize these antibodies of interest.

 

ii. Generation of VHH fragments

Recombinant VHH domains (VHHs) are inherently thermostable and exhibit the antigen-binding capacity of the camelid original heavy-chain antibody. VHHs have also been shown to be extremely plastic and capable of quantitative refolding. Small size (14-17 Kda) and increased plasticity provide VHHs with unique diagnostic and therapeutic potential.

Our platform generates phage-displayed libraries of camel-derived VHH fragments, enriched for species that selectively bind to specific immunoregulatory receptors expressed on the cell membrane, as well as to intracellular moieties. 

 
 

iii. Modulation of sequences of VHH fragment antibodies

Sequences of VHH fragments derived from our routine platforms are modified to facilitate successful intracellular delivery and greater ability to cross the blood-brain-barrier.

 

iii. Scale-up of VHH fragment antibody expression

Various expression systems are explored to arrive at the optimal method to produce significant quantities of VHH fragment antibody protein.

 
 

Timelines

1. Generation of Polyclonal Antibodies

Immunizing of camels (With client antigen, inclusive up to three ELISA screenings for titer determination)
12-16 weeks

Antibody purification
(Protein-A or size chromatography)
2 weeks

Antigen affinity purification
3 weeks

2. VHH generation

Immunizing of camels
12-16 weeks

Setup of library construction and target panning
3 weeks 

Polyclonal phase / target antigen antigen specific enrichment
2 weeks 

Monoclonal phase / target antigen monoclonal antigen sdab (ELISA) (400 clones) 96 cfu (1x 96 well plate)
4 weeks

Miniprep and glycerol back up of antigen-reactive antibodies (≤24 clones)
2 days 

Sequencing of client-indicated antigen-reactive fragment
2 weeks