All lanes : Anti-Hsp27 antibody [EPR5477] (ab109376) at 1/1000 dilution

Lane 1 : Wild-type HeLa cell lysate
Lane 2 : HSPB1 knockout HeLa cell lysate

Lysates/proteins at 20 µg per lane.

Performed under reducing conditions.

Predicted band size: 23 kDa
Observed band size: 23 kDa

Lanes 1- 2: Merged signal (red and green). Green - ab109376 observed at 23 kDa. Red - Anti-GAPDH antibody [6C5] - Loading Control (ab8245) observed at 37 kDa.

 ab109376 was shown to react with Hsp27 in wild-type HeLa cells in western blot. Loss of signal was observed when knockout cell line ab261738 (knockout cell lysate ab256945) was used. Wild-type HeLa and HSPB1 knockout HeLa cell lysates were subjected to SDS-PAGE. Membrane was blocked for 1 hour at room temperature in 0.1% TBST with 3% non-fat dried milk. ab109376 and Anti-GAPDH antibody [6C5] - Loading Control (ab8245) overnight at 4°C at a 1 in 1000 Dilution and a 1 in 20000 dilution respectively. Blots were developed with Goat anti-Rabbit IgG H&L (IRDye^®800CW) preadsorbed (ab216773) and Goat anti-Mouse IgG H&L (IRDye^®680RD) preadsorbed (ab216776) secondary antibodies at 1 in 20000 dilution for 1 hour at room temperature before imaging.

Overlay histogram showing wild-type HAP1 (green line) and HSPB1 knockout HAP1 cells (red line) stained with ab109376. The cells were fixed with 4% formaldehyde (10 min)  and then permeabilized with 0.1% PBS-Triton X-100 for 15 min. The cells were then incubated in 1x PBS / 10% normal goat serum to block non-specific protein-protein interactions followed by the antibody (ab109376, 1µg/ml) for 30 min at 22°C. The secondary antibody used was Alexa Fluor^® 488 goat anti-rabbit IgG (H&L) presorbed (ab150081) at 1/2000 dilution for 30 min at 22°C.

A rabbit IgG isotype control antibody  (ab172730) was used at the same concentration and conditions as the primary antibody (HAP1 wildtype - black line, knockout HSPB1 HAP1- grey line). Unlabelled sample was also used as a control (this line is not shown for the purpose of simplicity).

Acquisition of >5,000 events were collected using a 50 mW Blue laser (488nm) and 530/30 bandpass filter.

Immunocytochemistry/Immunofluorescence analysis of HeLa (human cervix adenocarcinoma) cells labelling Hsp27 with purified ab109376 at 1/500. Cells were fixed with 100% methanol. ab150077, Alexa Fluor^® 488-conjugated goat anti-rabbit IgG (1/1000) was used as the secondary antibody. Nuclei were counterstained with DAPI (blue).

Secondary Only Control: PBS was used instead of the primary antibody as the negative control.

All lanes : Anti-Hsp27 antibody [EPR5477] (ab109376) at 1/1000 dilution

Lane 1 : Wild-type HAP1 whole cell lysate
Lane 2 : Hsp27 knockout HAP1 whole cell lysate
Lane 3 : HeLa whole cell lysate
Lane 4 : MCF7 whole cell lysate

Lysates/proteins at 20 µg per lane.

Predicted band size: 23 kDa

Lanes 1 - 4: Merged signal (red and green). Green - ab109376 observed at 27 kDa. Red - loading control, ab8245, observed at 37 kDa.

ab109376 was shown to specifically react with Hsp27 in wild-type HAP1 cells as signal was lost in Hsp27 knockout HAP1 cells. Wild-type and Hsp27 knockout samples were subjected to SDS-PAGE.  Ab109376 and ab8245 (Mouse anti GAPDH loading control) were incubated overnight at 4°C at 1/1000 dilution and 1/20000 dilution respectively. Blots were developed with Goat anti-Rabbit IgG H&L (IRDye^® 800CW) preabsorbed ab216773 and Goat anti-Mouse IgG H&L (IRDye^® 680RD) preabsorbed ab216776 secondary antibodies at 1/20000 dilution for 1 hour at room temperature before imaging.

All lanes : Anti-Hsp27 antibody [EPR5477] (ab109376) at 1/1000 dilution

Lane 1 : HeLa cell lysate
Lane 2 : COS-1 cell lysate
Lane 3 : BxPC-3 cell lysate
Lane 4 : HT-1376 cell lysate

Lysates/proteins at 10 µg per lane.

Predicted band size: 23 kDa
Observed band size: 27 kDa why is the actual band size different from the predicted?