MtoZ Biolabs utilizes a high-resolution LC-MS/MS platform to launch the antibody sequence profiling service enabling comprehensive analysis of antibody sequences. This service is suitable for evaluating antibody molecular design and monitoring sequence quality of candidate molecules, providing reliable molecular weight data as a foundation for antibody development and sequence confirmation.

Overview

Antibodies are B cell-secreted immunoglobulins (Ig) composed of two heavy chains and two light chains linked via disulfide bonds in a Y-shaped architecture. The variable regions (VH/VL) and CDRs determine antigen recognition specificity and sequence analysis significance. Antibody sequence analysis enables accurate determination of the actual amino acid sequences of both light and heavy chains, elucidation of CDR composition, and identification of sequence variants, supporting therapeutic antibody engineering, monoclonal antibody discovery, and immune repertoire characterization.

Avram, O. et al. Frontiers in Immunology, 2018.

Figure 1. The diversity of Antibody Sequences and Structures.

Antibody Sequence Profiling Service at MtoZ Biolabs

MtoZ Biolabs integrates antibody sequence spectral profiles with high-resolution LC-MS platforms to launch the Antibody Sequence Profiling Service, providing comprehensive characterization centered on full-length heavy and light chain amino acid sequences, subunit composition, and sequence variant distribution.

• Identify full-length amino acid sequences of antibody heavy and light chains

• Define sequence composition and variant states within CDRs and framework regions

• Characterize sequence mismatches, residue substitutions, and residual chemical modifications

• Evaluate differences in sequence homogeneity across experimental or thermal conditions

Our analysis delivers a robust understanding of antibody sequence integrity and molecular form distribution, supporting researchers with reliable data for downstream studies.

Workflow of Antibody Sequence Profiling Service

1. Sample Extraction

Isolate antibody proteins or Fab/ScFv fragments, completing purification and pre-digestion QC.

2. Peptide Separation

Separate tryptic antibody peptides using nano-flow or nLC chromatography to generate well-defined elution peaks.

3. MS/MS Acquisition

Acquire tandem MS fragmentation spectra, capturing complementary sequence tags across CDRs and framework regions.

4. Spectral Calibration

Apply MS mass correction, isotopic envelope calibration, and noise filtering to minimize spectral distortion.

5. Sequence Interpretation

Perform peptide-to-database alignment and assemble a report including full-length or variable-region sequence tables, CDR localization, mass error, and representative spectra.

de Graaf, S. C. et al. mAbs, 2022.

Figure 2. Three Approaches in MS-Based Antibody Sequencing.

Why Choose MtoZ Biolabs?

• Comprehensive Coverage: High sequence coverage enabling accurate resolution of variable regions and CDR domains.
• Reliable Results: Mature calibration systems firmly control isotope distribution and multiple charge state errors.
• High Sensitivity: Compatible with low-abundance antibody fragments and high dynamic-range samples.
• Customized Analysis: Analysis strategies optimized based on antibody type and study objectives.
• One-Stop Delivery: Coverage includes sample assessment, mass spectrometry acquisition, sequence interpretation, and formal report output.

Applications of Antibody Sequence Profiling Service

1. Biomarker Discovery

Suitable for identifying and profiling variable region sequences of clinical response antibodies, supporting the selection of potential immune biomarkers.

2. Metabolic Response Signatures

Applicable for recognizing key antibody sequences in metabolic intervention models, enabling extraction of immune-metabolism associated sequence biomarkers.

3. Differential Sequence Screening

Used to analyze differential distribution of antibody sequences across biological sample groups, helping generate candidate immune biomarker sequence lists.

4. Functional Domain Assignment

Applied to map sequence attribution of functional antibody domains, supporting targeted immune biomarker development.

Deliverables

• Comprehensive Experimental Details
• Materials, Instruments, and Methods
• Heavy and Light Chain Sequence Interpretation Results
• Post-translational Modification (PTM) Sequence Annotations
• Representative Mass Spectrometry Spectral Images
• Bioinformatics Analysis
• Raw Data Files

FAQ

Q1: What kind of samples are suitable?

A1: Soluble, clear, and highly pure antibody samples are suitable, including recombinant monoclonal antibodies, fusion antibodies, and protein complexes purified by affinity or chromatography. Low-salt buffers are preferred, and large amounts of contaminating proteins and highly viscous matrices should be avoided.

Q2: What is the service general workflow?

A2:

Q3: What data formats are provided?

A3: The main delivery formats include:

• Raw mass spectrometry data files

• Antibody heavy/light chain sequence resolution results (XLSX/CSV)

• Key spectra and correlation curve images (PNG/TIFF)

• Comprehensive analysis report (PDF)

If special analytical requirements exist, data formats can be customized according to project specifications.

Q4: How should I prepare samples?

A4: To ensure optimal identification results, it is recommended to prepare samples in the following aspects:

• Sample Purity: Solution should be free of precipitates and turbidity; control salt, glycerol, surfactant, and residual proteins.
• Sample Preservation: Short-term storage at 4℃, long-term storage at -80℃; avoid repeated freeze-thaw cycles.
• Sample Transportation: Cold chain (ice packs or dry ice), sealed to prevent leakage, and prevent the introduction of particles.
• Additional Information: Includes antibody source, buffer composition, and theoretical sequence/structural expectations for easy calibration and analysis.

For more information, please refer to Sample Submission Guidelines for Proteomics, Sample Submission Guidelines for Metabolomics.

Start Your Project with MtoZ Biolabs    

Contact us to discuss your experimental design or request a quote. Whether you are conducting antibody sequence confirmation for candidate biomarkers or advancing antibody engineering and functional research, MtoZ Biolabs provides robust and traceable analytical support.