Journal: Cancer Immunology, Immunotherapy : CII

Article Title: Determination of optimum vitamin D3 levels for NK cell-mediated rituximab- and obinutuzumab-dependent cellular cytotoxicity

doi: 10.1007/s00262-018-2224-y

Figure Lengend Snippet: Effect of vitamin D3 levels on NK cell-mediated ADCC a–c summarize the ADCC-mediated lysis rates of all individuals at four actually achieved 25-OH-D3 serum levels at an E:T ratio of 2.5:1 and 0.1 µg/ml of rituximab-loaded DAUDI cells (a), obinutuzumab-loaded DAUDI cells (b) and trastuzumab-loaded ZR-75-1 breast cancer cells (c). 25-OH-D3 substitution restricted to the lower normal range (32.1 ng/ml) did not affect the NK cell-mediated ADCC. After continued substitution only rituximab- (p = 0.001) and obinutuzumab-mediated ADCC (p = 0.007) increased significantly at a 25-OH-D3 serum level of 66.1 ng/ml compared to base line, while the increase of trastuzumab-mediated ADCC was not significant (p = 0.064). Further 25-OH-D3 substitution to 94.1 ng/ml resulted in a weak, but significant decline of the rituximab-mediated ADCC (p = 0.045) compared to the maximum, while this decline was minimal for obinutuzumab (p = 0.145) and remained unchanged for trastuzumab (p = 0.49). d Relative 25-OH-D3 induced increase of target cell lysis at different antibody concentrations and E:T ratios after the substitution of 25-OH-D3 serum levels to 66.1 ng/ml. The curves show the decreasing impact of 25-OH-D3 with increasing antibody concentrations and higher E:T ratios and the smaller effect on obinutuzumab-ADCC compared to rituximab-ADCC. Signs and symbols: Check/closed line: rituximab (E:T = 2.5:1); quadrate/dashed line: rituximab (E:T = 5:1); triangle/dotted line: obinutuzumab (E:T = 2.5:1); circle/chain line: obinutuzumab (E:T = 5:1)

Article Snippet: As targets for the trastuzumab-dependent ADCC, HER2/neu + cells of the breast cancer cell line ZR-75-1 (CLS Cell lines Service GmbH, Eppelheim, Germany) were used.

Techniques: Lysis

Journal: Cancer Immunology, Immunotherapy : CII

Article Title: Determination of optimum vitamin D3 levels for NK cell-mediated rituximab- and obinutuzumab-dependent cellular cytotoxicity

doi: 10.1007/s00262-018-2224-y

Figure Lengend Snippet: NK-cell activity and NK cell-mediated ADCC before vitamin D3 substitution NK-cell activity (0 µg/ml antibody) and NK cell-mediated ADCC of all 15 subjects with a deficiency or insufficiency of vitamin D3 against CD20+ DAUDI cells treated with rituximab (a) or obinutuzumab (b) and ZR-75-1 breast cancer cells treated with trastuzumab, respectively (c). The E:T ratio was 5:1. Boxplots indicate lower quartile, median, and the upper quartile. The lower whisker depicts the lowest and the upper whisker the highest lysis rate. Statistics: p values below or above the solid lines were determined by two-sided T test and p values over the broken lines by ANOVA. d In contrast to both anti-CD20 antibodies rituximab and obinutuzumab, the ADCC induced by the HER2/neu-specific antibody trastuzumab against CD20+ DAUDI cells (black columns) was not increased compared to the NK-cell activity against naïve DAUDI cells (trastuzumab vs. naïve, p = 0.50). Conversely, rituximab and obinutuzumab dependent ADCC against the HER2/neu+ cell line ZR-75-1 (white columns) was not increased compared to the NK-cell activity (without antibodies) against ZR-75-1 breast carcinoma cells (rituximab vs. naïve, p = 0.46; obinutuzumab vs. naïve, p = 0.12). NK cells used in this ADCC were derived from subject ID #75 before substitution and used at an E:T ratio of 5:1

Article Snippet: As targets for the trastuzumab-dependent ADCC, HER2/neu + cells of the breast cancer cell line ZR-75-1 (CLS Cell lines Service GmbH, Eppelheim, Germany) were used.

Techniques: Activity Assay, Whisker Assay, Lysis, Derivative Assay