To clarify whether mantle cell lymphomas (MCLs) are related to naive pre-germinal center B cells (expressing nonmutated rearranged VH genes) or to germinal center-derived memory B cells (expressing mutated rearranged V” genes), clonal IgH gene rearrangements using DNA from six MCLs were polymerase chain reaction (PCR)-amplified and analyzed for the presence of somatic mutations. For comparison,...

Lysosome-rich particles prepared from adult rat testes but not from liver released large amounts of various lysosomal enzymes into the supernatant medium when they were incubated at 37” at physiological PH. Evidence was presented that the thermally sensitive lysosomes were present in advanced germinal cells but not in spermatogonia. Lysosomal rich particles isolated from regressed testes, obtai...

Primary immunization with the T-cell-dependent antigen (4-hydroxy-3-nitrophenyl)acetyl (NP) coupled to human serum albumin results in the development of two pathways of B-cell development, the extrafollicular pathway and the germinal center pathway. Soluble, deaggregated NP-human serum albumin injected before immunization results in a marked diminution of clonable higher-affinity antibody-formi...

Rates of Mu transposon insertions and excisions are both high in late somatic cells of maize. In contrast, although high rates of insertions are observed in germinal cells, germinal excisions are recovered only rarely. Plants doubly homozygous for deletion alleles of rad51A1 and rad51A2 do not encode functional RAD51 protein (RAD51-). Approximately 1% of the gametes from RAD51+ plants that carr...

The products of the Rag1 and Rag2 genes drive genomic V(D)J rearrangements that assemble functional immunoglobulin and T cell antigen receptor genes. Expression of the Rag genes has been thought to be limited to developmentally immature lymphocyte populations that in normal adult animals are primarily restricted to the bone marrow and thymus. Abundant RAG1 and RAG2 protein and messenger RNA was...

The germinal center (GC) reactions are critical for the production of high-affinity antibodies that comprise protective humoral response elicited by infection or vaccination. GCs initiated through interaction B cells with T follicular helper (Tfh) cells. While transcriptional regulation Tfh differentiation has been studied in great detail, impact micro RNAs (miRNAs) on development and stability...

Translocations involving the BCL-6 gene are common in the diffuse large cell subtype of non-Hodgkin's lymphoma. Invariably, the BCL-6 coding region is intact, but its 5' untranslated region is replaced with sequences from the translocation partner. The present study shows that BCL-6 expression is regulated in lymphocytes during mitogenic stimulation. Resting B and T lymphocytes contain high lev...

BACKGROUND Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disease (PTLD) encompasses a histologically broad range of lesions, arising from the expanded pool of EBV-infected B cells in the immunocompromised host. Identification of the precise cellular origin of these tumours could clarify their pathogenesis. METHODS Of 13 cases of EBV-positive cases of PTLD characteris...

Precise identification of the male germinal stem cell population is important for their practical use in programs dedicated to the integration of exogenous genetic material in testicular tissues. In the present study, our aim was to identify germinal cell populations in the testes of pubertal and adult cockerels based on the detection of the nuclear DNA content by fluorescence-activated cell so...

Chemokine receptors on T cells are frequently categorized as functioning either in immune system homeostasis within lymphoid organs, or in peripheral inflammation. CXCR3 is in the latter category and is reported to be expressed selectively on Th1 cells. We found that CXCR3 was expressed in vivo on newly activated tonsillar CD4(+) T cells. Using CD4(+) T cells from cord blood, we found that CXCR...