PT  - JOURNAL ARTICLE
AU  - Smith, Penelope R
AU  - Cavenagh, Jamie D
AU  - Milne, Tim
AU  - Howe, Denise
AU  - Wilkes, Susanna J
AU  - Sinnott, Paul
AU  - Forster, Greta E
AU  - Helbert, Matthew
TI  - Benign monoclonal expansion of CD8+ lymphocytes in HIV infection
AID  - 10.1136/jcp.53.3.177
DP  - 2000 Mar 01
TA  - Journal of Clinical Pathology
PG  - 177--181
VI  - 53
IP  - 3
4099  - http://jcp.bmj.com/content/53/3/177.short
4100  - http://jcp.bmj.com/content/53/3/177.full
SO  - J Clin Pathol2000 Mar 01; 53
AB  - Background—A transient expansion of the CD8+ T cell pool normally occurs in the early phase of HIV infection. Persistent expansion of this pool is observed in two related settings: diffuse infiltrative lymphocytosis syndrome (DILS) and HIV associated CD8+ lymphocytosis syndrome. Aim—To investigate a group of HIV infected patients with CD8+ lymphocytosis syndrome with particular emphasis on whether monoclonality was present. Methods—A group of 18 patients with HIV-1 infection and persistent circulating CD8+ lymphocytosis was compared with 21 HIV positive controls. Serum samples were tested for antinuclear antibodies, antibodies to extractable nuclear antigens, immunoglobulin levels, paraproteins, human T lymphotropic virus type 1 (HTLV-1), Epstein-Barr virus, and cytomegalovirus serology. Lymphocyte phenotyping and HLA-DR typing was performed, and T cell receptor (TCR) gene rearrangement studies used to identify monoclonal populations of T cells. CD4+ and CD8+ subsets of peripheral blood lymphocytes were purified to determine whether CD8+ populations inhibited HIV replication in autologous CD4+ cells. Results—A subgroup of patients with HIV-1 infection was found to have expanded populations of CD8+ T cell large granular lymphocytes persisting for 6 to 30 months. The consensus immunophenotype was CD4− CD8+ DRhigh CD11a+ CD11c+ CD16− CD28± CD56− CD57+, consistent with typical T cell large granular lymphocytes expressing cellular activation markers. Despite the finding of monoclonal TCR gene usage in five of 18 patients, there is evidence that the CD8+ expansions are reactive populations capable of mediating non-cytotoxic inhibition of HIV replication. Conclusions—A subgroup of HIV positive patients has CD8+ lymphocytosis, but despite the frequent occurrence of monoclonal TCR gene usage there is evidence that this represents an immune response to viral infection rather than a malignant disorder.