Anti-Carboxymethyl Lysine (C-terminal) polyclonal antibody

Treatment-free remission (TFR) is emerging as a new therapy goal for chronic myeloid leukemia (CML) patients in the tyrosine kinase inhibitors (TKI) era. Data indicates the unfavorable success rate of TFR. This study aimed to compare and evaluate the clinical value of dd-PCR in predicting relapse in CML patients entering TFR. Using dd-PCR and RT-qPCR technology, dynamic BCR/ABL transcripts were detected in 13 CML patients who discontinued TKI treatment after sustaining undetectable BCR-ABL levels for a median time of 25 months. The results showed that in 13 patients, only 2 cases (22.2%) of 9 patients who executed planned discontinuation achieved TFR within 12 months. In the first 6 months, the detection rate of BCR/ABL transcripts by dd-PCR was higher than that by RT-qPCR and the two methods kept a positive correlation (r=0.9651, P=0.0349). Meanwhile, the time of detectable BCR/ABL by dd-PCR were significantly shorter (P<0.05), which was an average of 2.98 months earlier than RT-qPCR. The total TKI therapy and MR4.5 duration time related with TFR were longer in patients with intermediate or high Sokal risk scores (p<0.05). The dd-PCR could be more sensitive than RT-qPCR for monitoring BCR/ABL transcripts of CML patients with deep molecular response to TKI. The technique can be used as a preferred method to detect the transcripts in the first 6 months after TKI cessation.

In an attempt to identify novel markers and immunological targets in leukemic stem cells (LSCs) in acute myeloid leukemia (AML) and chronic myeloid leukemia (CML), we screened bone marrow (BM) samples from patients with AML (n = 274) or CML (n = 97) and controls (n = 288) for expression of cell membrane antigens on CD34(+)/CD38(-) and CD34(+)/CD38(+) cells by multicolor flow cytometry. In addition, we established messenger RNA expression profiles in purified sorted CD34(+)/CD38(-) and CD34(+)/CD38(+) cells using gene array and quantitative polymerase chain reaction. Aberrantly expressed markers were identified in all cohorts. In CML, CD34(+)/CD38(-) LSCs exhibited an almost invariable aberration profile, defined as CD25(+)/CD26(+)/CD56(+)/CD93(+)/IL-1RAP(+). By contrast, in patients with AML, CD34(+)/CD38(-) cells variably expressed "aberrant" membrane antigens, including CD25 (48%), CD96 (40%), CD371 (CLL-1; 68%), and IL-1RAP (65%). With the exception of a subgroup of FLT3 internal tandem duplication-mutated patients, AML LSCs did not exhibit CD26. All other surface markers and target antigens detected on AML and/or CML LSCs, including CD33, CD44, CD47, CD52, CD105, CD114, CD117, CD133, CD135, CD184, and roundabout-4, were also found on normal BM stem cells. However, several of these surface targets, including CD25, CD33, and CD123, were expressed at higher levels on CD34(+)/CD38(-) LSCs comparedwith normal BMstem cells. Moreover, antibody-mediated immunological targeting through CD33 or CD52 resulted in LSC depletion in vitro and a substantially reduced LSC engraftment in NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ (NSG) mice. Together, we have established surface marker and target expression profiles of AML LSCs and CML LSCs, which should facilitate LSC enrichment, diagnostic LSC phenotyping, and development of LSC-eradicating immunotherapies.