TLR4 agonist preparation - MPLA-SM

Notification:  MPLA-SM* is a new preparation of MPLA-SM (now removed from our catalog) which is more potent at inducing human TLR4 responses.

Monophosphoryl Lipid A from Salmonella minnesota R595

InvivoGen provides two preparations of Monophosphoryl Lipid A extracted from the lipopolysaccharide (LPS) of Salmonella minnesota Re595 (Re mutant), a rough strain of Gram-negative bacteria, for Toll-like receptor 4 (TLR4) activation:

MPLA-SM* and MPLA-SM are extracted from LPS using treatment with acid and heat followed by chromatography [1].  These preparations contain a mix of MPLA congeneric forms differing in the number of acyl chains. It has been suggested that this mix is responsible for the partial TLR4 agonist function of some preparations [2]. MPLA-SM* is a new reference in our catalog. It results from an improved process of MPLA-SM extraction. While MPLA-SM* and MPLA-SM have the same ability to activate murine TLR4, MPLA-SM* is more potent than MPLA-SM at inducing human TLR4 responses (see figures). 

 More details
 

Key features:

• Agonists of mouse and human TLR4
• Negligible TLR2 activity
• Each lot is functionally tested
   

Note: MPLA-SM* is also available in pre-clinical grade as MPLA-SM* Vaccigrade™.

References:

1. Qureshi N. et al., 1985. Monophosphoryl lipid A obtained from lipopolysaccharides of Salmonella minnesota R595. Purification of the dimethyl derivative by high-performance liquid chromatography and complete structural determination. J. Biol. Chem. 260, 5271–8.
2. Wang YQ. et al., 2020. MPL Adjuvant Contains Competitive Antagonists of Human TLR4. Front. Immunol. 11:577823.

Figures

MPLA-SM and MPLA-SM* induce a similar dose-dependent response in HEK-Blue™ mTLR4 cells. The cells were incubated with increasing concentrations of two preparations of S. minnesota monophosphoryl lipid A, MPLA-SM, and MPLA-SM*. After overnight incubation in HEK-Blue™ detection medium, a SEAP detection growth medium, the activation of mouse (m)TLR4 was assessed by determining the presence of SEAP in the supernatant. Data are expressed as optical density at 630 nm (±SEM).

MPLA-SM* is more potent than MPLA-SM at inducing a dose-dependent response in HEK-Blue™ hTLR4 cells. The cells were incubated with increasing concentrations of two preparations of S. minnesota monophosphoryl lipid A, MPLA-SM, and MPLA-SM*. After overnight incubation in HEK-Blue™ detection medium, a SEAP detection growth medium, the activation of human (h)TLR4 was assessed by determining the presence of SEAP in the supernatant. Data are expressed as optical density at 630 nm (±SEM).

Specifications

Species: Salmonella enterica serovar minnesota mutant R595

Specificity: TLR4 agonist

Working concentration: 3 ng - 1 μg/ml (for human TLR4) and 10 pg - 1 µg/ml (for mouse TLR4)

Appearance: Clear lipidic film

Solubility: 1 mg/ml in DMSO

Quality control:

• Biological activity has been tested using HEK-Blue™ hTLR4 cells.
• The presence of other bacterial components (e.g. lipoproteins) is controlled using HEK-Blue™ TLR2 cells.

Contents

MPLA-SM* is provided as a clear, lyophilized lipidic film.

• 1 mg Monophosphoryl Lipid A (MPLA-SM*)

 The product is shipped at room temperature.

 Store at -20°C. Upon resuspension, prepare aliquots and store them at -20°C.

 The product is stable for 6 months at -20°C.

 Avoid repeated freeze-thaw cycles