Aedes albopictus is known to be superinfected with two strains of Wolbachia (wAlbA and wAlbB). In previous works we described the generation of a transinfected Ae. albopictus line, named "ARwP", by replacing the natural Wolbachia double-infection with a single heterologous bacterial strain from Culex pipiens. Reported infection data and CI features appeared consistent with a promising use of ARwP line as a tool for Ae. albopictus suppression strategies. We also demonstrated that in crosses between wild type males and ARwP females only wAlbA causes full CI, while wAlbB and wPip display an asymmetrical CI pattern. Data from literature indicate that Wolbachia density in natural populations varies within a wide range. In particular wAlbA strain, besides being variable among individuals, tends to dramatically decrease with male age. In this work, we confirmed these general findings on mosquitoes collected in Northern and Central Italy. In addition, we evaluated the influence of male wAlbA and wAlbB loads on CI penetrance in crosses with ARwP transinfected females. To this aim we combined a quantitative PCR approach with egg hatching data from age controlled crossing experiments. We clearly found that the wAlbA "mod+" function towards ARwP females is expressed in a density-dependent manner. In fact, young males with very low wAlbA load showed a weakened CI, while older males with higher wAlbA density were associated to strong CI. Differently, wAlbB (a weaker CI inducer towards wPip females) showed neither an evident age-dependent density variation in males nor a significant density-dependent impact on CI in crosses with ARwP females. The results of this work are an unprecedented contribution for evaluating how strong and stable is the bidirectional CI pattern between wild superinfected and ARwP mosquitoes. Obtained data are discussed in the perspective of developing a bio-ecologically safe and long-term effective area-wide suppression strategy against Ae. albopictus.