What conclusion can be made from an inhibition study with anti-Le^b where the tubes with Lewis substance are negative?

When conducting an inhibition study with anti-Le^b antibodies, a critical aspect to evaluate is the response when Lewis substances are present. The primary role of the Lewis antigens, including Le^b, is to serve as specific targets for their corresponding antibodies in such studies.

In this context, if the tubes containing Lewis substances yield negative results, it strongly indicates that the anti-Le^b antibodies are indeed binding to the specific determinants present on the red blood cells rather than being neutralized by the Lewis substances. The absence of agglutination or reaction when Lewis substance is added confirms the specificity of the antibody to the Le^b antigen. Essentially, it demonstrates that the anti-Le^b is functioning as expected, and thereby confirms its presence.

Other outcomes, such as a positive control or the presence of additional antibodies cannot detract from the clear conclusion drawn from the negative results in the context of the study. This negative reaction indicates that the anti-Le^b is validated because its expected interaction with the Lewis substance did not occur—thus supporting the assertion that anti-Le^b antibody is indeed present and functioning as confirmed by the inhibition study.