Rab27A/B, Abcam, ab313575

Our team performed a comprehensive review of the scientific literature to identify studies using antibodies against human Rab27A and Rab27B, followed by extraction and evaluation of available data according to pAbmAbs rating criteria.

YCharOS conducted a systematic head-to-head comparison of 14 commercially available antibodies against Rab27A and 7 against Rab27B across multiple applications

Antibodies were tested by WB using lysates (40 µg total protein) from U-87 MG WT cells and cells with siRNA-mediated knockdown (KD) of Rab27A or Rab27B. The same cell lines were used for IF testing. In addition, antibodies were evaluated by IP using HAP1 (Rab27A) or U-87 MG (Rab27B) cell lysates (1 mg), following YCharOS standard protocols (see reference).

In WB (1:1000 antibody dilution), ab313575 detects a single band at the expected size (~24 kDa) in WT U-87 MG lysate, with a very faint corresponding band in Rab27A KD lysate. A band of similar size and intensity is observed in Rab27B KD lysate. Together, these results indicate that the antibody specifically detects Rab27A.

In IP, the antibody (2 µg) enriches the Rab27A signal compared to the starting material (U-87 MG cell lysate) and reduces the signal in the unbound fraction, indicating good but incomplete depletion of the target from the cell lysate. Rab27A in the starting material, unbound fraction, and precipitate was detected by WB using the same antibody.

In IF, the antibody (1:500 antibody dilution) resulted in a strong signal from WT U-87 MG cells with no signal from Rab27A KD cells.

We highly encourage other scientists to share their observations.