Biomedical subjects

Kevin N Heller

Publications and source records attributed to Kevin N Heller.

3 recordsLinked to original sources

PubMed2006

Distinct memory CD4+ T-cell subsets mediate immune recognition of Epstein Barr virus nuclear antigen 1 in healthy virus carriers.

CD4+ T cells, specific for transforming latent infection with the Epstein Barr virus (EBV), consistently recognize the nuclear antigen 1 of EBV (EBNA1). EBNA1-specific effector CD4+ T cells are primarily T-helper 1 (TH1) polarized. Here we show that most healthy EBV carriers have such IFN-secreting EBNA1-specific CD4+ T cells at a frequency of 0.03% of circulating CD4+ T cells. In addition, healthy carriers have a large pool of CD4+ T cells that proliferated in response to EBNA1 and consisted of distinct memory-cell subsets. Despite continuous antigen presence due to persistent EBV infection, half of the proliferating EBNA1-specific CD4+ T cells belonged to the central-memory compartment (TCM). The remaining EBNA1-specific CD4+ T cells displayed an effector-memory phenotype (TEM), of which a minority rapidly secreted IFN upon stimulation with EBNA1. Based on chemokine receptor analysis, all EBNA1-specific TCM CD4+ T cells were TH1 committed. Our results suggest that protective immune control of chronic infections, like EBV, includes a substantial reservoir of TCM CD4+ TH1 precursors, which continuously fuels TH1-polarized effector cells.

Antigens, Viral↗

PubMed2006

Virus-specific CD4+ T cells: ready for direct attack.

CD4+ T cells are classically thought to orchestrate adaptive immune responses. But recent studies demonstrate that they can also kill infected cells directly. A new paper shows that highly efficient processing of Epstein Barr virus (EBV) glycoproteins for presentation on MHC class II makes virus-transformed B cells susceptible to lysis by CD4+ T cells. Thus, antiviral vaccines should aim to stimulate both helper and cytolytic CD4+ T cells.

Animals↗

PubMed2004

Primary follicular lymphoma of the testis: excellent outcome following surgical resection without adjuvant chemotherapy.

The authors report a case of follicular lymphoma of the testis in a 3-year-old boy. Follicular lymphoma of childhood is rare, accounting for less than 5% of all non-Hodgkin lymphomas in the pediatric population. Children with follicular NHL have typically been described as presenting with localized disease, with a preponderance of male patients. The authors conducted a comprehensive review of the literature and found that this patient is the only child reported to have localized follicular lymphoma of the testis successfully treated without systemic chemotherapy. In all previously reported cases, a favorable outcome was seen following surgical resection and chemotherapy. This patient has remained disease-free for more than 2 years after surgical resection alone. The successful outcome in this case following surgical resection, without postoperative adjuvant chemotherapy, suggests that localized follicular non-Hodgkin lymphoma in children may not be associated with occult systemic disease and that subsequent chemotherapy may not be necessary for cure.

Biomarkers, Tumor↗