Title: Exosomes in the serum of Acute Myeloid Leukemia patients induce dendritic cell tolerance: Implications for immunotherapy
Author: Benites, Bruno Deltreggia; Da Silva Santos Duarte, Adriana; Longhini, Ana Leda Figueiredo; Santos, Irene; Alvarez, Marisa Claudia; De Morais Ribeiro, Ligia Nunes; Paula, Eneida De; Saad, Sara Teresinha Olalla
Is part of: VACCINE, v. 37, p. 1377 - 1383
Citation: Benites, Bruno Deltreggia; Da Silva Santos Duarte, Adriana; Longhini, Ana Leda Figueiredo; Santos, Irene; Alvarez, Marisa Claudia; De Morais Ribeiro, Ligia Nunes; Paula, Eneida De; Saad, Sara Teresinha Olalla; Exosomes in the serum of Acute Myeloid Leukemia patients induce dendritic cell tolerance: Implications for immunotherapy. VACCINE, v.37, p. 1377-1383, 2019
Abstract: Exosomes may represent an interesting antigenic pulse for new forms of anti-tumor immunotherapy. We evaluated exosomes from serum of patients with acute myeloid leukemia (AML) as an antigenic source for dendritic cells (DC) and the effects upon antitumor cytotoxicity, assessed by the percentage of specific lysis of K562 leukemic cells in co-cultures. Surprisingly, incubation of exosomes with DCs decreased lysis of K562, which may correspond to a mechanism of tumor evasion in vivo. However, when immature DCs were pulsed with exosomes purified from K562 culture supernatants, the lysis of target cells was notably enhanced, associated with a substantial increase in the expression of the maturation marker CD83. Thus, the development of vaccines using patients' exosomes would probably add no benefits to the treatment of AML; alternately, exosomes from cultured cells may represent an effective way for maturing DCs into a cytotoxic phenotype, without the immunosuppression observed with patients' exosomes. (C) 2019 Elsevier Ltd. All rights reserved.
Keywords: exosomes; nanotracking analysis;
Subjects: CIENCIAS_BIOLOGICAS; Biofísica de Processos e Sistemas;
Funding: This study was supported by Grant no. 2011/51959-0 from the Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP).