CXCR1 and HIV-1 infection: While there is variation in the amount of RsaA that is present for each recombinant compared to the Cc-Control, this is unlikely to have a great impact on the ability of each recombinant to prevent HIV-1 infection as a unmodified C. crescentus expresses 40,000–60,000 copies of the RsaA protein on its’ surface26,31, suggesting that even a 50% reduction in RsaA proteins will still lead to substantial expression of the recombinant protein, which is supported by our previous HIV-1 studies20,22.