Benign monoclonal expansion of CD8+ lymphocytes in HIV infection.

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.

Monoclonal Epstein-Barr virus-related lymphoproliferative disorder following adult acute lymphoblastic leukaemia.

A 31-year-old patient in remission of acute lymphoblastic leukaemia (ALL), receiving oral maintenance chemotherapy (6-mercaptopurine, methotrexate (MTX), cyclophosphamide), developed a monoclonal, Epstein-Barr virus (EBV)-related lymphoproliferative disorder (LPD). Treatment consisted of excisional biopsy and the discontinuation of maintenance chemotherapy. To our knowledge, this is the first such report in an adult. The histological similarity to previous reports of 'lymphomatoid granulomatosis' following paediatric ALL suggests that they are the same disease. MTX may play a central role in the development of LPD in this setting. Although it is a rare complication of ALL, EBV-related LPD should be considered in patients who develop lymphadenopathy.

Ploidy as a prognostic indicator in oesophageal squamous carcinoma and its relationship to various histological criteria.

One hundred surgically resected squamous cell carcinomas of the oesophagus were studied retrospectively to assess the significance of DNA aneuploidy as determined by flow cytometry using paraffin-embedded tissue. DNA aneuploidy was not an independent prognostic indicator but was found to be associated with tumour necrosis and host/tumour interface fibrosis. When tumours confined to submucosa or muscle wall were assessed, diploid tumours had a poorer survival rate than DNA aneuploid tumours. Other histological variables studied were tumour differentiation, depth of infiltration, glandular and small cell differentiation, lymphatic and vascular spread and host inflammatory response. These failed to show any significant association with ploidy.