Differential cross sections of charged particles in inelastic pp collisions as a function of pT have been measured at s = 0.9, 2.76 and 7 TeV at the LHC. The pT spectra are compared to NLO-pQCD calculations. Though the differential cross section for an individual s cannot be described by NLO-pQCD, the relative increase of cross section with s is in agreement with NLO-pQCD. Based on these measurements and observations, procedures are discussed to construct pp reference spectra at s = 2.76 and 5.02 TeV up to pT = 50 GeV/c as required for the calculation of the nuclear modification factor in nucleus-nucleus and proton-nucleus collisions.publishedVersio