This defect is specific to the B-cell lineage because other lymphocyte populations appear to be normal.

The use of flowcytometry to understand the in vitro effects of cytokine stimulation makes one's task easier as studies can be carried out on mixed lymphocyte populations.

In AIDS patients, perhaps the most important factor with respect to treatment is the use of highly active anti-retroviral therapy (HAART), which affects the CD4+ lymphocyte population and the level of immunosuppression.

Interestingly, TTP was induced by LPS in vivo more slowly (after 4 hours vs 1-2 hours) and to a lesser degree in the lymphocyte population than in neutrophils or monocytes.

Recent research demonstrates that reduction of lymphocyte populations can impair cognition in mice, and that restoration of lymphocytes restores cognitive abilities.

In a subset of 23 cases, cluster analysis using Paint-a-gate software (BD) was done to correlate the size of the different lymphocyte populations with the phenotypically aberrant T-cell clusters.

T cells are unique among the lymphocyte populations in their ability to further specialize as mature cells and become yet more mature.

However subsequently, cytokine and cytokine receptor expression ensue, and the cytokines ultimately drive the clonal expansion and functional differentiation of the antigen-selected lymphocyte populations.

This experimental approach was also used to investigate other lymphocyte populations, including "natural killer" cells.

The lymphocyte population consists of T cells (CD4 and CD8 positive 75%), B cells and NK cells ( 25% combined).