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Reactive lymphocytes show a range of morphologic features. Reactive lymphocytes with immunoblast-like morphology are large cells with high nuclear-cytoplasmic ratios, condensed chromatin, and deeply basophilic cytoplasm. Another type of reactive lymphocyte has less condensed chromatin and abundant, pale blue cytoplasm that may appear to "hug" adjacent red blood cells. These cells are also called Downey type II cells. They can be seen in a variety of conditions, but are often increased in infectious mononucleosis due to EBV infection.