Design, synthesis, and evaluation of the effect of potential peptides against CD38: An in silico and in vitro study
Mohsen Nabi-Afjadi1, Bahareh Dabirmanesh1, S Mohsen Asghari2
1Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
Abstract:
The transmembrane glycoprotein known as CD38 (cluster of differentiation 38) is a desirable target for targeted therapeutics as it is essential for immune response and cell signaling, especially in hematological malignancies. The current study aimed to design antibody/nanobody-derived peptides using bioinformatic tools and experimentally investigate their specific binding and impact on the extracellular CD38 expressing cells. Following the synthesis of one of the peptides that indicated somewhat better in silico results, known as CDR3a23 (L-pep), and its circular version as C-pep, flow cytometry was used to assess each one's specific binding to CD38. MTT and trypan blue exclusion assays were then used to investigate the peptide's impact. The peptide's anti-proliferative mechanism was also confirmed by cell cycle analysis and apoptosis after annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI) double staining. Finally, the L-pep with Kd of 630 nm, indicated high affinity to CD38. The IC50 values of the L-pep and C-pep against the HL-60 cells were achieved as 540 nM and 780 nM (P < 0.0001), respectively. Also, when the peptides combined with 1 µM ATRA, these values significantly decreased to 390 nM and 630 nM (P < 0.0001), respectively. During arresting the cells at the G1 phase, the total apoptosis of the L-pep and C-pep achieved as 47.5 % and 34.3 %, respectively, which significantly increased to 72.5 % and 55.3 %, respectively, in combination with 1 µM ATRA. Through their specific binding and suppression of cell growth, our research identified potential peptides against cells exhibiting high levels of CD38.
Insights
Researchers designed novel peptides targeting CD38 (cluster of differentiation 38) for hematological malignancies. These peptides show specific binding and inhibit cancer cell growth, offering potential new therapeutics.
Area of Science:
- Biochemistry
- Immunology
- Pharmacology
Background:
- CD38 (cluster of differentiation 38) is a transmembrane glycoprotein crucial for immune response and cell signaling.
- It is a significant target in hematological malignancies, driving the need for targeted therapeutics.
Purpose of the Study:
- To design antibody/nanobody-derived peptides targeting CD38 using bioinformatics.
- To experimentally validate the specific binding and anti-proliferative effects of these designed peptides on CD38-expressing cells.
Main Methods:
- Bioinformatic peptide design and in silico analysis.
- Synthesis and characterization of L-pep and C-pep.
- Flow cytometry for assessing CD38 binding specificity.
- MTT and trypan blue assays for cell viability.
- Cell cycle analysis and Annexin V/PI staining for apoptosis assessment.
Main Results:
- L-pep demonstrated high affinity to CD38 (Kd = 630 nM).
- L-pep and C-pep exhibited significant anti-proliferative effects on HL-60 cells with IC50 values of 540 nM and 780 nM, respectively.
- Combination therapy with ATRA notably enhanced peptide efficacy, reducing IC50 values and increasing apoptosis.
Conclusions:
- The designed peptides, particularly L-pep, show specific binding to CD38 and possess potent anti-proliferative activity.
- These peptides represent promising candidates for targeted therapy against hematological malignancies with high CD38 expression.
- Combination with ATRA further potentiates their therapeutic potential.
