Rab27B, Cell Signaling Technology, 17572

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), 17572 detects a single band at the expected size (~24 kDa) in WT U-87 MG and Rab27A lysates, with no corresponding band in lysates from Rab27A KD cells, indicating that the antibody specifically detects Rab27B.

In IP, the antibody (2 µg) precipitates Rab27B, as detected by WB using the same antibody 17572. However, the intensity of the precipitated band is comparable to the bands observed in the starting material and the unbound fraction, indicating possible but incomplete depletion of the target from the cell lysate.

In IF, the antibody (1:800 antibody dilution) resulted in a strong signal from U-87 MG WT with no background observed in Rab27B KD cells.

We highly encourage other scientists to share their observations.