diff --git a/src/OSPSuite.Core/Domain/Builder/ExpressionProfileBuildingBlock.cs b/src/OSPSuite.Core/Domain/Builder/ExpressionProfileBuildingBlock.cs
index d34e7c4c4..a98142a38 100644
--- a/src/OSPSuite.Core/Domain/Builder/ExpressionProfileBuildingBlock.cs
+++ b/src/OSPSuite.Core/Domain/Builder/ExpressionProfileBuildingBlock.cs
@@ -6,7 +6,7 @@
 
 namespace OSPSuite.Core.Domain.Builder
 {
-   public class ExpressionProfileBuildingBlock : PathAndValueEntityBuildingBlockFromPKSim<ExpressionParameter>
+   public class ExpressionProfileBuildingBlock : PathAndValueEntityBuildingBlockFromPKSim<ExpressionParameter>, ILookupBuildingBlock<InitialCondition>
    {
       private readonly StartValueCache<InitialCondition> _initialConditions = new StartValueCache<InitialCondition>();
       public override string Icon => Type.IconName;
@@ -19,6 +19,11 @@ public class ExpressionProfileBuildingBlock : PathAndValueEntityBuildingBlockFro
 
       public virtual string Category { get; private set; }
 
+      InitialCondition ILookupBuildingBlock<InitialCondition>.ByPath(ObjectPath path)
+      {
+         return _initialConditions[path];
+      }
+
       public override string Name
       {
          get => ExpressionProfileName(MoleculeName, Species, Category);
@@ -44,7 +49,7 @@ public void RemoveInitialCondition(InitialCondition initialCondition)
       {
          if (initialCondition == null)
             return;
-         
+
          _initialConditions.Remove(initialCondition.Path);
          initialCondition.BuildingBlock = null;
       }
@@ -62,6 +67,7 @@ public override void AcceptVisitor(IVisitor visitor)
       }
 
       public IReadOnlyCollection<InitialCondition> InitialConditions => _initialConditions;
+      public IReadOnlyCollection<ExpressionParameter> ExpressionParameters => _allValues;
 
       public override void UpdatePropertiesFrom(IUpdatable source, ICloneManager cloneManager)
       {
@@ -76,7 +82,26 @@ public override void UpdatePropertiesFrom(IUpdatable source, ICloneManager clone
          Name = sourceExpressionProfile.Name;
 
          _initialConditions.Clear();
-         sourceExpressionProfile.InitialConditions.Each(initialCondition => AddInitialCondition(cloneManager.Clone(initialCondition)));
+         sourceExpressionProfile.InitialConditions.Each(initialCondition =>
+            AddInitialCondition(cloneManager.Clone(initialCondition)));
+      }
+
+      public IEnumerator<InitialCondition> GetEnumerator()
+      {
+         return _initialConditions.GetEnumerator();
+      }
+
+      public void Add(InitialCondition pathAndValueEntity)
+      {
+         _initialConditions.Add(pathAndValueEntity);
+         pathAndValueEntity.BuildingBlock = this;
+      }
+
+      public void Remove(InitialCondition pathAndValueEntity)
+      {
+         if (pathAndValueEntity == null)
+            return;
+         _initialConditions.Remove(pathAndValueEntity.Path);
       }
    }
 }
\ No newline at end of file
diff --git a/src/OSPSuite.Core/Domain/Builder/InitialConditionsBuildingBlock.cs b/src/OSPSuite.Core/Domain/Builder/InitialConditionsBuildingBlock.cs
index ee4de07d2..f31417d7e 100644
--- a/src/OSPSuite.Core/Domain/Builder/InitialConditionsBuildingBlock.cs
+++ b/src/OSPSuite.Core/Domain/Builder/InitialConditionsBuildingBlock.cs
@@ -2,6 +2,11 @@
 
 namespace OSPSuite.Core.Domain.Builder
 {
+   public interface ILookupBuildingBlock<T> : IBuildingBlock<T> where T : IBuilder
+   {
+      T ByPath(ObjectPath path);
+   }
+
    public class InitialConditionsBuildingBlock : PathAndValueEntityBuildingBlock<InitialCondition>
    {
       public InitialConditionsBuildingBlock()
diff --git a/src/OSPSuite.Core/Domain/Builder/PathAndValueEntityBuildingBlock.cs b/src/OSPSuite.Core/Domain/Builder/PathAndValueEntityBuildingBlock.cs
index 4c80da5dd..0e852d611 100644
--- a/src/OSPSuite.Core/Domain/Builder/PathAndValueEntityBuildingBlock.cs
+++ b/src/OSPSuite.Core/Domain/Builder/PathAndValueEntityBuildingBlock.cs
@@ -8,7 +8,7 @@
 
 namespace OSPSuite.Core.Domain.Builder
 {
-   public abstract class PathAndValueEntityBuildingBlock<T> : BuildingBlock, IBuildingBlock<T> where T : PathAndValueEntity
+   public abstract class PathAndValueEntityBuildingBlock<T> : BuildingBlock, ILookupBuildingBlock<T> where T : PathAndValueEntity
    {
       protected Cache<ObjectPath, T> _allValues = new Cache<ObjectPath, T>(x => x.Path, x => null);
 
@@ -47,6 +47,11 @@ IEnumerator IEnumerable.GetEnumerator()
          return GetEnumerator();
       }
 
+      T ILookupBuildingBlock<T>.ByPath(ObjectPath path)
+      {
+         return this[path];
+      }
+
       public override void AcceptVisitor(IVisitor visitor)
       {
          base.AcceptVisitor(visitor);
diff --git a/src/OSPSuite.Core/Domain/Constants.cs b/src/OSPSuite.Core/Domain/Constants.cs
index 3a3fd357e..ba906e1ef 100644
--- a/src/OSPSuite.Core/Domain/Constants.cs
+++ b/src/OSPSuite.Core/Domain/Constants.cs
@@ -534,6 +534,7 @@ private static string compositeNameFor(char separator, params string[] names)
 
       public static class Serialization
       {
+         public const string INITIAL_CONDITIONS = "InitialConditions";
          public const string MACRO_COMMAND = "MacroCommand";
          public const string SIMPLE_COMMAND = "SimpleCommand";
          public const string LABEL_COMMAND = "LabelCommand";
diff --git a/src/OSPSuite.Core/Domain/Services/QuantityValuesUpdater.cs b/src/OSPSuite.Core/Domain/Services/QuantityValuesUpdater.cs
index 983698ae8..9c05b3d25 100644
--- a/src/OSPSuite.Core/Domain/Services/QuantityValuesUpdater.cs
+++ b/src/OSPSuite.Core/Domain/Services/QuantityValuesUpdater.cs
@@ -59,7 +59,7 @@ public void UpdateQuantitiesValues(ModelConfiguration modelConfiguration)
 
       private void updateParameterFromExpressionProfiles(ModelConfiguration modelConfiguration)
       {
-         modelConfiguration.SimulationConfiguration.ExpressionProfiles?.SelectMany(x => x).Each(x => updateParameterValueFromStartValue(modelConfiguration, x, getParameter));
+         modelConfiguration.SimulationConfiguration.ExpressionProfiles?.SelectMany(x => x.ExpressionParameters).Each(x => updateParameterValueFromStartValue(modelConfiguration, x, getParameter));
       }
 
       private void updateParameterFromIndividualValues(ModelConfiguration modelConfiguration)
diff --git a/tests/OSPSuite.Core.Tests/Domain/ExpressionProfileBuildingBlockSpecs.cs b/tests/OSPSuite.Core.Tests/Domain/ExpressionProfileBuildingBlockSpecs.cs
index 74ad90fc8..a53256aad 100644
--- a/tests/OSPSuite.Core.Tests/Domain/ExpressionProfileBuildingBlockSpecs.cs
+++ b/tests/OSPSuite.Core.Tests/Domain/ExpressionProfileBuildingBlockSpecs.cs
@@ -41,7 +41,7 @@ protected override void Context()
          _expressionProfileBuildingBlock.Add(new ExpressionParameter().WithName("name1"));
          var initialCondition = new InitialCondition().WithName("ic1");
          initialCondition.Path = new ObjectPath("path1");
-         _expressionProfileBuildingBlock.AddInitialCondition(initialCondition);
+         _expressionProfileBuildingBlock.Add(initialCondition);
 
          var clonedInitialCondition = new InitialCondition().WithName(initialCondition.Name);
          clonedInitialCondition.Path = initialCondition.Path;
@@ -58,8 +58,8 @@ public void the_updated_expression_profile_should_have_properties_set()
          sut.Name.ShouldBeEqualTo("Molecule|Species|Name");
          sut.Type.ShouldBeEqualTo(ExpressionTypes.MetabolizingEnzyme);
          sut.PKSimVersion.ShouldBeEqualTo("11.1");
-         sut.Count().ShouldBeEqualTo(1);
-         sut.InitialConditions.Count().ShouldBeEqualTo(1);
+         sut.Count<ExpressionParameter>().ShouldBeEqualTo(1);
+         sut.Count<InitialCondition>().ShouldBeEqualTo(1);
       }
    }