Vaccines to Prevent Systemic Mycoses: Holy Grails Meet Translational Realities

In this issue of the Journal, Spellberg et al. [1] report that immunization with a recombinant protein (rAls3p-N) mixed with aluminum hydroxide gel (Alhydrogel) can protect mice from a lethal candidal infection. This is an extension of their original finding of protection resulting from this and related Als recombinant proteins when used with Freund's adjuvant. From a purely immunologic perspective, their finding that protection can also be achieved using Alhydrogel in place of Freund's adjuvant might be viewed as a modest advance. However, because Alhydrogel has been widely used as an adjuvant in US Food and Drug Administration (FDA)-approved vaccines, these studies represent a milestone in the movement of the vaccine toward clinical testing. Thus, on the occasion of this report, it may be useful to review the potential value of vaccines for systemic mycoses in general, using vaccines for coccidioidomycosis as a specific example, and to review the challenges these vaccine candidates will face before becoming realities in the marketplace.