Read the pattern first
Start with the reactive cells, then look for the antibody pattern that explains them best.
Quick start
Learn only what you need, then move into practice.
This page gives the minimum setup needed to work the practice panel. Use the full guide when you want the blood bank background, antibody concepts, and deeper explanations of the patterns you will see.
Basics
What antibody identification is trying to answer.
The test is about matching patient serum or plasma against reagent red cells with known antigen profiles. The goal is to identify which antibody or antibodies are present so the panel can be interpreted correctly.
Know the usual clues
Clinically significant antibodies usually react at 37 C and/or AHG (antihuman globulin), and the autocontrol or DAT (direct antiglobulin test) can help separate alloantibody from autoantibody or mixed findings.
Use nonreactive cells
Nonreactive antigen-positive cells help rule out unlikely antibodies, and dosage-sensitive systems need homozygous cells for stronger evidence.
Match the panel
The strongest clue is not one cell, but how the whole panel fits together.
Workflow
A simple order for reading a practice case.
1. Start with the pattern
- Look at the phase and strength of reactivity.
- Check the autocontrol and DAT.
- Ask whether the case looks like alloantibody, autoantibody, or mixed findings.
2. Rule out and confirm
- Use nonreactive cells to rule out unlikely antibodies.
- Watch for dosage and homozygous expression.
- Use the reactive and nonreactive cells that fit best to support your final answer.
The full guide goes deeper into rule-of-3 logic, enzyme effects, DAT interpretation, and the common patterns for Rh, Kell, Duffy, Kidd, and Lewis.
Marks
The only notation the practice page uses.
Rule out
Rule out means a nonreactive cell carries the antigen for an antibody you are considering. If that cell does not react, that antibody becomes less likely. For dosage-sensitive antibodies, homozygous cells are stronger rule-out evidence than heterozygous cells.
In this app, rule-out marks are placed on the antigen cells:Het means one antigen copy and Hom means two antigen copies.
Rule in
Rule in means the overall pattern supports one antibody better than the others. A common teaching target is 3 antigen-positive reactive cells and 3 antigen-negative nonreactive cells that fit the same specificity.
In this app, proof marks go on the cell number: + for an antigen-positive reactive cell and - for an antigen-negative nonreactive cell.
Dosage
Dosage means an antibody reacts more strongly with cells that have two copies of the antigen than with cells that have one copy. That is why Rh, Duffy, Kidd, and MNS are classic dosage systems.
Status row
The footer status row is just a running judgment: Suspect means possible, Partial means some evidence, and Out means ruled out.
Next steps
Pick the level of detail you want next.
Full guide
Use this when you want the complete walkthrough with phase-by-phase detail, rule-out strategy, dosage, enzyme effects, and references.
Open the full guidePractice
Use this when you want to apply the workflow to panel cases and start building speed.
Start practicing