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F G Kroese

Publications and source records attributed to F G Kroese.

At least 19 recordsLinked to original sources
PubMed1995

Role of environmental antigen in the development of IgG+ cells in the bursa of fabricius.

IgG+ cells were detected in the bursa of Fabricius after hatching by immunofluorescence staining of single cells and immunohistologic studies using mAb anti-Ig gamma-heavy chain. The frequency of IgG+ cells in the bursa increased rapidly immediately after hatching. In histologic studies, most of the IgG+ cells were found in the medullary areas of the bursal follicle. Isolation of the bursa from the gut by bursal duct ligation before hatching suppressed the development of IgG+ cells in the bursa after hatching. In addition, administration of Ags into the bursal lumen just before bursal duct ligation caused a significant increase of IgG+ cells in the bursa compared with the isolated bursa. However, parenteral administration of Ags had no effect on the frequency of IgG+ cells in the isolated and normal bursa. These results suggest that Ags in the bursa are a prerequisite for the development of IgG+ cells in the bursa. Although the majority of IgG+ bursal cells were IgM+ IgG+ double-positive cells, sorted Bu1+ bursal cells, which contained 99.9% of IgG+ cells but not plasma cells, synthesized de novo IgM but little or no IgG. Therefore, it is likely that surface IgG on the bursal cells is not produced locally, but is trapped by IgM+ bursal cells. We speculate that Ags derived from the bursal lumen form immune complexes within the bursa, which are subsequently trapped on the surface of IgM+ bursal cells mediated either by Fc-receptors, C3 receptors, or surface Ig.

Animals↗
PubMed1995

Identification and kinetics of two recently bone marrow-derived B cell populations in peripheral lymphoid tissues.

In rats, the glycoprotein Thy-1 is expressed on recently bone marrow (BM)-generated B cells but not on mature recirculating follicular (RF) B cells. Here we demonstrate that Thy-1+ B cells consist of two phenotypically distinct, but developmentally related, populations: a population of newly formed (NF) B cells (IgMbr-IgDdu) that give rise to the second, less immature, Thy-1+ population of so-called early recirculating follicular (ERF) B cells (Thy-1+IgMduIgDbr) cells. These cells ultimately develop to RF-B cells (Thy-1-IgMbrIgDdu). Kinetic studies reveal that in absolute numbers per day most cells die at the transition of NF-B cells in the BM and those in the periphery: less cells die at later stages of B cell differentiation. Given the notion that this cell loss is not random, we speculate that NF-B cells and ERF-B cells may represent crucial steps during peripheral B cell development and their selection. Identification of their unique phenotype makes it possible to evaluate their roles in development of the antibody repertoire.

Animals↗
PubMed1994

MRC OX19 recognizes the rat CD5 surface glycoprotein, but does not provide evidence for a population of CD5bright B cells.

To clone the rat CD5 gene we first produced two rat CD5 probes. The probes were obtained by polymerase chain reaction (PCR) on rat genomic DNA using primers designed on conserved regions between mouse and human CD5. The screening of a rat cDNA library at high stringency using these probes resulted in a 1.5-kb positive clone. The DNA sequence of this clone confirmed its CD5 nature, but the clone appeared to lack part of the 5' and part of the 3' end. These missing 5' and 3' ends were obtained by PCR on rat thymus RNA. By ligating these PCR products to the original 1.5-kb CDM8 clone, a full-length rat CD5 gene was constructed. The full-length clone showed high identity with mouse and human CD5; however, at the 5' site of the gene a region of 36 nucleotides is present which is not seen in either mouse or human CD5. We have evidence that this sequence is a normal constituent of the rat CD5 gene: first, it is in frame with the rest of the CD5 coding sequence; second, it does not contain a stop codon; and third, it is also present in the CD5 gene of other rat strains. We transfected the full-length CD5 construct in COS cells and demonstrated that indeed the CD5 protein is recognized by MRC OX19. Although we showed that CD5 mRNA is present in rat B cells, extensive flow cytometry analysis using MRC OX19 as antibody failed to detect B cells expressing significant levels of CD5 on their cell surface compared to other B cells in any tissue or cell suspension tested from a variety of rat strains. This is in contrast with the mouse where a distinct population of B cells (B-1a cells) can be found expressing more CD5 than the other B cells. Either B-1 cells are not present in rats or CD5 is not the right phenotypic marker for rat B-1 cells. It still remains to be investigated whether a population of B cells with functions similar to those of murine B-1 cells is present in rats.

Amino Acid Sequence↗
PubMed1994

B cells specific for bromelain-treated erythrocytes are not derived from adult rat bone marrow.

As part of an evolutionary layered hematopoietic system, the B lymphocyte compartment consists of different lineages of B lymphocytes, which evolve sequentially during ontogeny. In mice, there is ample evidence for the existence of at least two lineages, a layer of B-1 cells (Ly-1 B cells) and the evolutionary more advanced layer consisting of conventional B cells. In a previous study we were unable to detect B-1 cells in the rat as determined by phenotypic markers. Here we studied the possible existence of putative B-1 cells in the rat based on some functional and developmental characteristics as have been described for mouse B-1 cells. We show that B cells secreting antibodies that recognize bromelain-treated mouse red blood cells (BrMRBC) can be identified in rat spleen, whereas these cells (in contrast to DNP-specific B cells) are virtually absent in lethally X-irradiated and bone marrow (BM) reconstituted animals. The number of anti-rMRBC-secreting B cells could not be restored to control levels by reconstitution with fetal liver cells or by cotransfer of 10(7) cells from peritoneal cavity, lymph node or Peyer's patches or up to 2 x 10(8) splenocytes. Although our findings thus suggest that B-1 cells (or B-1 like cells) may be present in rats, formal proof for the existence of such a lineage in rats awaits definition of these cells at the progenitor level.

Animals↗
PubMed1993

Kinetics of peritoneal B-1a cells (CD5 B cells) in young adult mice.

In the mouse, conventional B cells are continuously generated from precursor cells located in the bone marrow (BM), whereas the small subset of B-1 cells (formerly called Ly-1 B cells) constitute a self-replenishing population of cells. Here we studied the kinetics of murine peritoneal B-1a cells (i.e. B-1 cells expressing CD5). The actual number of B-1a cells in the peritoneal cavity that are proliferating, as detected by metaphase arrest and S-phase index, was below detection level, indicating that these cells do not divide significantly at this anatomical location. To establish the life-span of B-1a cells we used long-term administration of 5-bromo-2'-deoxyuridine in combination with three-color immunocytology on cytospin preparations. The renewal rate of peritoneal B-1a cells was 1.3% per day representing a 50% renewal time of 38 days. Splenic B cells and popliteal lymph node B cells (predominantly conventional B cells) showed an almost identical renewal rate of 1.1% per day. The data show that peripheral B cells from various lymphoid tissues and locations do not differ significantly in their renewal capacity, even though there are differences in their developmental origin.

Animals↗
PubMed1993

Evidence that intestinal IgA plasma cells in mu, kappa transgenic mice are derived from B-1 (Ly-1 B) cells.

B6-Sp6 transgenic mice carry fully rearranged (BALB/c-derived, Igh-Ca allotype) mu heavy chain and kappa light chain transgenes, specific for trinitrophenyl, on a C57BL background (Igh-Cb allotype). FACS analyses show that the majority of B cells in peripheral lymphoid organs and bone marrow (BM) express transgenic IgM exclusively. A small proportion of the B cells, however, express endogenous IgM, usually concomitant with transgenic IgM. Three criteria establish that the endogenous IgM expressing B cells belong to the B-1 cell lineage. (i) Endogenous IgM expressing B cells in B6-Sp6 mice have the same localization pattern as B-1 cells from normal animals: they are enriched in the peritoneal cavity. (ii) The endogenous IgM+ B cells have the phenotype of B-1 cells: the endogenous IgM+ peritoneal B cells express Mac-1 (CD11b) and low levels of IgD, and most also express CD5 (Ly-1). (iii) B6-Sp6 BM poorly reconstitutes endogenous IgM+ B cells, just as adult BM from normal mice poorly reconstitutes B-1 cells. In contrast, B cells which only express the transgene are readily reconstituted by B6-Sp6 BM. The few endogenous IgM+ cells in the B6-Sp6 BM recipients are located in the peritoneal cavity and have the phenotype of B-1b cells (previously the Ly-1 B sister population), which are known to be reconstituted by adult BM. Two-color immunofluorescence staining of tissue sections from the gut and from isolated gut lamina propria cells shows the presence of many IgA containing cells, about one-third of which simultaneously express cytoplasmic (transgenic) IgM. The C-region of this IgA is produced by endogenous C alpha genes, because the transgene encodes only for C mu. Furthermore, the majority of gut IgA containing cells do not express the idiotype of the transgene, indicating that most of the gut IgA cells are encoded by endogenous VH genes and thus the result of an isotype switch from endogenous IgM expressing B cells. Since the endogenous IgM+ cells are B-1 cells (both B-1a and B-1b), the data strongly indicate that the intestinal IgA plasma cells also belong to the B-1 cell lineage.

Animals↗
PubMed1993

Kinetics of B cell subpopulations in peripheral lymphoid tissues: evidence for the presence of phenotypically distinct short-lived and long-lived B cell subsets.

A small proportion of the sIg+ B lymphocytes in peripheral lymphoid organs [22% in spleen and 6% in lymph node (LN)] in rat carries the Thy-1 antigen. These Thy-1+ B cells represent newly formed bone marrow (BM) derived (or immature) B cells. In this study we investigated the kinetic behavior of Thy-1+ and Thy-1- B cells in various lymphoid tissues. The renewal rates of these B cells in young adult rats were determined by continuous administration of 5-bromo-2-deoxyuridine (BrdU) for up to 6 weeks. At several time intervals, Thy-1+ and Thy-1- B cell subpopulations in BM, blood, spleen and popliteal LN were analyzed for the presence of incorporated BrdU, using three-color immunocytology on cytospin preparations. In all tissues studied, the Thy-1+ B cells were rapidly renewed with a rate that varied between 58% (BM) and 22% (LN) per day. Virtually all Thy-1+ B cells were labeled by BrdU within a period of 8-16 days, indicating that all these cells are relatively short-lived. By contrast, the replacement of Thy-1- B cells in these tissues was 30-40 times lower, and ranged between 2.0 and 0.8% per day. In absolute numbers we estimate that 57 million Thy-1+ B cells are renewed per day in the BM whereas only 10 million Thy-1- B cells are replaced in the pool of long-lived peripheral B cells. This implicates a cell loss of 80% at the transition of the Thy-1+ to the Thy-1- B cell stage. The few B cells that actually become incorporated into the pool of mature B cells are most probably selected on the basis of the specificity of their sIg.

Animals↗
PubMed1992

The extent of clonal structure in different lymphoid organs.

To gain insight into the clonal organization of lymphoid organs, we studied the distribution in situ of donor-derived cells in near-physiological chimeras. We introduced RT7b fetal liver cells into nonirradiated congenic RT7a neonatal rats. The chimerism 6-20 wk after injection ranged from 0.3 to 20%. The numbers of cell clones simultaneously contributing to cell generation in a particular histological feature were deduced from the variance in donor cell distribution. In bone marrow and thymus, donor-derived lymphoid cells were found scattered among host cells, indicating a high mobility of cells. In bone marrow, donor cells were evenly distributed over the entire marrow, even at low chimerism. This indicates that leukopoiesis is maintained by the proliferation of many clones. In the thymus, the various lobules showed different quantities of donor-derived lymphoid cells. Mathematical analysis of these differences indicated that 17-18 cell division cycles occur in the cortex. In spleen, the distribution of donor-derived cells over the germinal centers indicated that 5 d after antigenic stimulation, germinal centers develop oligoclonally. The main conclusions of this work are that (a) bone marrow and thymus are highly polyclonal; (b) 17-18 divisions occur between prothymocyte and mature T cell; and (c) lymphoid cells disperse rapidly while proliferating and differentiating.

Animals↗
PubMed1992

Immunohistological characterization of proximal colonic lymphoid tissue in the rat.

Proximal colonic lymphoid tissue (PCLT) is a lymphoid structure located in the proximal colon of the mouse and the rat. In the present investigation we studied the immunomorphology and cytology of PCLT in the rat. We also studied sites of lymphocyte proliferation using the BrdU-anti BrdU technique. Results demonstrated no evident phenotypical differences between the lymphocyte populations of PCLT and either jejunal or ileal Peyer's patches (PP). The majority of the lymphocytes within PCLT were B cells localized in follicles, which were separated from each other by interfollicular T cell areas. Germinal centers (GC), containing ED5+ follicular dendritic cells, are found within PCLT follicles. The T cell areas contained both MHC Class II+ interdigitating cells and high endothelial venules. Studies using BrdU-anti BrdU indicated that lymphocyte proliferation within PCLT takes place mainly in germinal centers. Together the data show that the organization, lymphoid constituents, and sites of lymphocyte production are very similar in PCLT and PP. We therefore conclude that PCLT in the rat is not a Bursa equivalent, but more likely a PP with some special characteristics.

Animals↗
PubMed1992

The evolution of immune memory and germinal centers.

Antibody responses in homoiothermic and poikilothermic vertebrates are significantly different in their heterogeneity and affinity range, and in the speed of the secondary response following repeated antigenic stimulation. This article presents the hypothesis that the evolutionary development of unique lymphoid structures, the germinal centers, in combination with the development of a distinct B-cell lineage, is a determining feature of these differences.

Animals↗
PubMed1991

The expression of B cell surface receptors. III. The murine low-affinity IgE Fc receptor is not expressed on Ly 1 or 'Ly 1-like' B cells.

The distribution of IgE FcR (Fc epsilon R)-positive and -negative B cells was examined in normal adult mice. Using three-color flow cytometry, the expression of the Fc epsilon R was analyzed on various B-cell subsets present in the peritoneum and spleen. The results demonstrate that in the peritoneal cavity, the Fc epsilon R is not expressed on the large majority of Ly 1+ B cells and Ly 1-, Mac 1+ sister B cells. The receptor is present, however, on the small number of conventional B cells residing in the peritoneum. Although interleukin 4 (IL-4) can increase the levels of the Fc epsilon R on conventional B cells, incubation of Ly 1 and sister B cells with IL-4 did not result in the expression of the Fc epsilon R. When examining B cells present in the spleen, a small subset of B cells was consistently found to be Fc epsilon R-. These Fc epsilon R- cells were IgM-bright, IgD-dull and largely Ly 1- and Mac 1-negative. Staining of splenic tissue sections revealed that the Fc epsilon R- B cells were primarily localized to the marginal zones, whereas the Fc epsilon R+ B cells were found in the follicles. Taken together, the results indicate that the Fc epsilon R may be a useful marker in delineating the various B-cell subsets. In the peritoneum, the Fc epsilon R appears to discriminate conventional B cells from those of the Ly 1/sister lineage, and in the spleen it is likely to distinguish resting follicular B cells from Ly 1/sister and marginal zone B cells.

Animals↗