Browsing by Subject "Lymphoid Tissue"

Now showing 1 - 3 of 3

Open Access
In situ studies of the primary immune response to (4-hydroxy-3-nitrophenyl)acetyl. II. A common clonal origin for periarteriolar lymphoid sheath-associated foci and germinal centers.
(J Exp Med, 1992-09-01) Jacob, J; Kelsoe, G
In the genetically restricted response that follows immunization with (4-hydroxy-3-nitrophenyl)acetyl coupled to protein carriers, two distinct populations of B cells are observed in the spleens of C57BL/6 mice. By 48 h postimmunization, foci of antigen-binding B cells appear along the periphery of the periarteriolar lymphoid sheaths. These foci expand to contain large numbers of antibody-forming cells that neither bind the lectin, peanut agglutinin, nor mutate the rearranged immunoglobulin variable region loci. Germinal centers containing peanut agglutinin-positive B cells can be observed by 96-120 h after immunization. Although specific for the immunizing hapten, these B cells do not produce substantial amounts of antibody, but are the population that undergoes somatic hypermutation and affinity-driven selection. Both focus and germinal center populations are pauciclonal, founded, on average, by three or fewer B lymphocytes. Despite the highly specialized roles of the focus (early antibody production) and germinal center (higher affinity memory cells) B cell populations, analysis of VH to D to JH joins in neighboring foci and germinal centers demonstrate that these B cell populations have a common clonal origin.
Open Access
Molecular characteristics of mantle cell lymphoma presenting with clonal plasma cell component.
(The American journal of surgical pathology, 2011-02) Visco, Carlo; Hoeller, Sylvia; Malik, Jeffrey T; Xu-Monette, Zijun Y; Wiggins, Michele L; Liu, Jessica; Sanger, Warren G; Liu, Zhongfeng; Chang, Julie; Ranheim, Erik A; Gradowski, Joel F; Serrano, Sergio; Wang, Huan-You; Liu, Qingquan; Dave, Sandeep; Olsen, Brian; Gascoyne, Randy D; Campo, Elias; Swerdlow, Steven H; Chan, Wing C; Tzankov, Alexander; Young, Ken H
The normal counterparts of mantle cell lymphoma (MCL) are naive, quiescent B cells that have not been processed through the germinal center (GC). For this reason, although lymphomas arising from GC or post-GC B cells often exhibit plasmacytic differentiation, MCL rarely presents with plasmacytic features. Seven cases of MCL with a monotypic plasma cell (PC) population were collected from 6 centers and were studied by immunohistochemistry, fluorescence immunophenotyping and interphase cytogenetics as a tool for the investigation of neoplasms analysis, capillary gel electrophoresis, and restriction fragment length polymorphism of immunoglobulin heavy chain analysis of microdissections of each of the MCL and PC populations to assess their clonal relationship. The clinical presentation was rather unusual compared with typical MCL, with 2 cases arising from the extranodal soft tissues of the head. All MCL cases were morphologically and immunohistochemically typical, bearing the t(11;14)(q13;q32). In all cases, the PC population was clonal. In 5 of the 7 cases, the MCL and PC clones showed identical restriction fragments, indicating a common clonal origin of the neoplastic population. The 2 cases with clonal diversity denoted the coexistence of 2 different tumors in a composite lymphoma/PC neoplasm. Our findings suggest that MCL can present with a PC component that is often clonally related to the lymphoma, representing a rare but unique biological variant of this tumor.
Open Access
SIV-induced terminally differentiated adaptive NK cells in lymph nodes associated with enhanced MHC-E restricted activity.
(Nature communications, 2021-02-24) Huot, Nicolas; Rascle, Philippe; Petitdemange, Caroline; Contreras, Vanessa; Stürzel, Christina M; Baquero, Eduard; Harper, Justin L; Passaes, Caroline; Legendre, Rachel; Varet, Hugo; Madec, Yoann; Sauermann, Ulrike; Stahl-Hennig, Christiane; Nattermann, Jacob; Saez-Cirion, Asier; Le Grand, Roger; Keith Reeves, R; Paiardini, Mirko; Kirchhoff, Frank; Jacquelin, Beatrice; Müller-Trutwin, Michaela
Natural killer (NK) cells play a critical understudied role during HIV infection in tissues. In a natural host of SIV, the African green monkey (AGM), NK cells mediate a strong control of SIVagm infection in secondary lymphoid tissues. We demonstrate that SIVagm infection induces the expansion of terminally differentiated NKG2a^low NK cells in secondary lymphoid organs displaying an adaptive transcriptional profile and increased MHC-E-restricted cytotoxicity in response to SIV Env peptides while expressing little IFN-γ. Such NK cell differentiation was lacking in SIVmac-infected macaques. Adaptive NK cells displayed no increased NKG2C expression. This study reveals a previously unknown profile of NK cell adaptation to a viral infection, thus accelerating strategies toward NK-cell directed therapies and viral control in tissues.