Table 2 Dendritic cell vaccine loading strategies

Loading DCs with leukemia-derived antigenic peptides

Long-term effect of DC vaccine

Broader tumor antigens for desired DC-based vaccines

Powerful ability to elicit antigen specific T cell functions

Targeting of different epitopes through different DC sources and/or routes of administration

Tumor antigens or HLA molecule expression or both may be lost in the course of disease

Tolerance increases due to the expression of shared antigens by normal cells

[12, 13, 48,49,50]

Pulsing DCs with whole leukemia apoptotic bodies

Contains both known and unknown immunogenic antigens

Canbe loaded with costimulatory and adhesion molecules

Can activate both the innate and adaptive immune systems to induce tumor-specific CD4 and CD8 T cells

Autoimmunity and/or immunotolerance can be the rare potential issues due to LAAs shared by normal hematopoietic cells

[12, 13, 42, 48, 51]

Pulsing DCs with leukemia cell lysates

Better than apoptotic body vaccines

A wider array of antigenic epitopes to stimulate a larger proportion of the CTL repertoire

May have interaction of DCs and NK cells

Lower capacity to elicit a broad spectrum of CTLs than apoptotic cells

Potential cytotoxicities

Longer processing and purification procedures than whole leukemic cell vaccines and mRNA vaccines

[12, 13, 48, 51]

Transfecting DCs with mRNA derived from leukemic cells

Higher transduction efficiency; strong T-cell stimulatory effect

Relatively longer mRNA antigen expression time

Various leukemic antigens can be included with the total mRNA

Amplified total tumor m-RNA can obtain unlimited amount of tumor antigens without the need for the search of specific tumor antigens in each patient

Passive m-RNA loading with weaker stimulatory capacity than m-RNA transfection

Safety and vector immunogenicity issues with the viral vectors

[12, 13, 48, 52]