InvivoGen provides Alum Hydroxide, a ready‑to‑use suspension of aluminium hydroxide, designed for in vitro assays. Its ability to induce the NLRP3 inflammasome has been validated using THP1-Null cells. Of note, Alum Hydroxide induces significantly higher levels of IL-1β by THP1-Null cells than Alum Crystals, using the HEK-Blue™ IL-1β cellular assay.
Aluminium salts (also referred to as alum), such as aluminium hydroxide, aluminium phosphate, or potassium aluminium sulfate, are commonly used vaccine adjuvants, although their mode of action in vivo remains unclear. Comprehensive research in vitro clearly demonstrates that alum induces an NLRP3 inflammasome-dependent induction of interleukin-1β (IL-1β) and IL-18 [1]. The NLRP3 inflammasome is an intracellular multi-protein complex that plays a central role in innate immunity [2, 3].
Of note, alum has been shown to trigger NLRP3 activation through lysosomal destabilization [4]. Interestingly, in vivo studies indicate a minimal role for the NLRP3 inflammasome in alum’s adjuvanticity [5]. The reason for this divergence between the in vitro and in vivo action of alum needs to be further investigated.
Key features of Alum Hydroxide:
- Inducer of the NLRP3 inflammasome in vitro
- Each lot is functionally tested
Read our review on the NLRP3 inflammasome.
Download our Practical guide on Inflammasomes.
References:
- Li H. et al., 2008. Cutting Edge: Inflammasome activation by Alum and Alum’s adjuvant effect are mediated by NLRP3. J Immunol. 181:17-21.
- Schroder K. & Tschopp J., 2010. The inflammasomes. Cell 140(6):821-32.
- Franchi L. et al.., 2012. . Sensing and reacting to microbes through the inflammasomes. Nat Immunol 13(4)325-32.
- Hornung V. et al., 2008. Silica crystals and aluminium salts activate the NALP3 inflammasome through phagosomal destabilization. Nature Immunol. 9:847-856.
- Wen Y. & Shi Y., 2016. Alum: an old dog with new tricks. Emerg Microbes Infect.5:e25.