VHH Single Domain Antibodies (Nanobodies) and Alpaca Secondary Antibodies

Alpaca-derived secondary antibodies from Jackson ImmunoResearch are available as total polyclonal cocktail and as VHH single domain antibodies (nanobodies).

We extended our portfolio of immunoglobulins for the life science research community with the new alpaca (Vicugna pacos) secondary antibodies. This host species is for example suitable for multiple labeling experiments, when antibodies from donkey or goat are not the right choice because of cross-reactivity. Alpaca together with Llama belong to the family of Camelidae. This species have a unique class of immunoglobulins among mammals. Three IgG-subclasses are found in their sera: the conventional IgG1 as well as IgG2 and IgG3. The latter lack the light chain and first-constant (CH1) domain (Fig.1). These heavy chain-only antibodies are smaller than normal IgGs, but are robust and have full specificity and affinity to their respective antigens.

Fig.1: Schematic of conventionel IgG (left), heavy chain-only Alpaca IgG2/ IgG3 antibody and VHH Single Domain Antibody (right).

Single Domain -VHH-Antibodies (Nanobodies) from Jackson ImmunoResearch.

Camelid derived VHH or single domain antibodies (commonly known as Nanobodies) have benefits for applications such as super-resolution imaging due to their excellent tissue penetration offered by their small size. Labeling with nanobodies brings the probe molecule into close enough proximity with the target necessary for accurate localization, reducing the linkage error associated with labeling using conventional antibodies.

Jackson ImmunoResearch Single Domain VHH Antibodies are currently available as Anti-Mouse, Anti-Rabbit, and Anti-Human, conjugated with dyes from the Alexa Fluor range and other commonly used probes.

In contrast to many other single domain VHH antibodies that are currently available Nanobodies from Jackson ImmunoResearch have the additional advantage of being polyclonal. Polyclonal single domain VHH antibodies allow for an even better signal amplification and have the same reduction in linkage error compared to monoclonal nanobodies

Polyclonal Nano Secondaries bind more epitopes on a primary antibody compared to monoclonal nanobodies as they have a broader recognition, but the the diameter of the complex remains comparable, with the distance between the probe and target protein being similar (Schematic from Jackson ImmunoResearch).

Alpaka Secondary Antibodies (polyclonal cocktail )

The polyclonal alpaca secondary antibodies (complete set of IgG1, IgG2 and IgG3) from Jackson ImmunoResearch detect Rabbit IgG (H+L), Mouse IgG (H+L) or Human IgG (H+L). To avoid any unspecific background staining due to BSA blocking, all antibodies are cross-adsorbed against bovine serum proteins. In addition, they have no cross-reactivity with rabbit, mouse or human, depending on your choice of species-reactivity. Here you can find anti-alpaca antibodies.

Secondary Antibody from Alpaca are available with the following conjugates:

• Unconjugated
• Horseradish Peroxidase
• Alkaline Phosphatase
• Biotin
• DyLight™ 405
• Cy™ 2
• Alexa Fluor® 488
• Fluorescein (FITC)
• Cy™ 3
• Rhodamine (TRITC)
• Alexa Fluor® 594
• Rhodamine Red-X™
• Alexa Fluor® 647
• Cy™ 5


  • Hamers-Casterman, C., T. Atarhouch, S. Muyldermans, G. Robinson, C. Hamers, E.B. Songa, N. Bendahman, and R. Hamers. 1993. Naturally occurring antibodies devoid of light chains. Nature. 363:446–448
  • De Genst E, Saerens D, Muyldermans S, Conrath K. Antibody repertoire development in camelids. Dev Comp Immunol (2006) 30:187–98.10.1016/j.dci.2005.06.010
  • Maass DR, Sepulveda J, Pernthaner A, Shoemaker CB. Alpaca (Lama pacos) as a convenient source of recombinant camelid heavy chain antibodies (VHHs). J Immunol Methods (2007) 324:13–25.10.1016/j.jim.2007.04.008