ABSTRACT
Acute kidney injury (AKI) is common in critically ill patients. Diuretics are used without any evidence demonstrating a beneficial effect on renal function. The objective of the present study is to determine the incidence of AKI in an intensive care unit (ICU) and if there is an association between the use of furosemide and the development of AKI. The study involved a hospital cohort in which 344 patients were consecutively enrolled from January 2010 to January 2011. A total of 132 patients (75 females and 57 males, average age 64 years) remained for analysis. Most exclusions were related to ICU discharge in the first 24 h. Laboratory, sociodemographic and clinical data were collected until the development of AKI, medical discharge or patient death. The incidence of AKI was 55% (95%CI = 46-64). The predictors of AKI found by univariate analysis were septic shock: OR = 3.12, 95%CI = 1.36-7.14; use of furosemide: OR = 3.27, 95%CI = 1.57-6.80, and age: OR = 1.02 (95%CI = 1.00-1.04). Analysis of the subgroup of patients with septic shock showed that the odds ratio of furosemide was 5.5 (95%CI = 1.16-26.02) for development of AKI. Age, use of furosemide, and septic shock were predictors of AKI in critically ill patients. Use of furosemide in the subgroup of patients with sepsis/septic shock increased (68.4%) the chance of development of AKI when compared to the sample as a whole (43.9%).
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Acute Kidney Injury/chemically induced , Diuretics/adverse effects , Furosemide/adverse effects , Shock, Septic/complications , Acute Kidney Injury/complications , Critical Illness , Intensive Care Units , Length of Stay , Prognosis , Risk FactorsABSTRACT
Toxoplasmosis is a devastating opportunistic infection that can affect immunocompromised patients such as cord blood transplantation (CBT) recipients. The clinical characteristics of 4 toxoplasmosis CBT patients treated at our institution are reviewed, together with 5 cases collected from the literature. The rate of toxoplasmosis in our hospital was 6% in CBT recipients and 0.2% in other types of allogeneic hematopoietic stem cell transplantation (P < 0.001). Five patients (56%) presented disseminated toxoplasmosis and 4 patients (44%) had localized infection in the central nervous system. In 5 of the 9 patients considered (56%), cytomegalovirus viral replication had been detected before the clinical onset of toxoplasmosis. Seven patients (78%) had previously developed graft-versus-host disease. All patients who exhibited disseminated disease died due to Toxoplasma infection. Pre-transplant serology was positive in 1 patient, negative in 3 patients, and not performed in another. Only 1 of these 5 patients with disseminated disease had received Toxoplasma prophylaxis with cotrimoxazole. It could be concluded that mortality in CBT patients with disseminated toxoplasmosis is unacceptably high. The negative results of serology in the majority of these cases, and its unspecific clinical presentation, makes diagnosis exceedingly difficult. Better diagnostic tests and prophylaxis strategy are needed in CBT recipients.
Subject(s)
Cord Blood Stem Cell Transplantation/adverse effects , Opportunistic Infections/epidemiology , Toxoplasma/isolation & purification , Toxoplasmosis/epidemiology , Adolescent , Adult , Child , Cytomegalovirus Infections/complications , Cytomegalovirus Infections/epidemiology , Female , Graft vs Host Disease/epidemiology , Humans , Male , Middle Aged , Opportunistic Infections/mortality , Opportunistic Infections/parasitology , Toxoplasma/genetics , Toxoplasmosis/mortality , Toxoplasmosis/parasitology , Young AdultABSTRACT
Acute kidney injury (AKI) is common in critically ill patients. Diuretics are used without any evidence demonstrating a beneficial effect on renal function. The objective of the present study is to determine the incidence of AKI in an intensive care unit (ICU) and if there is an association between the use of furosemide and the development of AKI. The study involved a hospital cohort in which 344 patients were consecutively enrolled from January 2010 to January 2011. A total of 132 patients (75 females and 57 males, average age 64 years) remained for analysis. Most exclusions were related to ICU discharge in the first 24 h. Laboratory, sociodemographic and clinical data were collected until the development of AKI, medical discharge or patient death. The incidence of AKI was 55% (95%CI = 46-64). The predictors of AKI found by univariate analysis were septic shock: OR = 3.12, 95%CI = 1.36-7.14; use of furosemide: OR = 3.27, 95%CI = 1.57-6.80, and age: OR = 1.02 (95%CI = 1.00-1.04). Analysis of the subgroup of patients with septic shock showed that the odds ratio of furosemide was 5.5 (95%CI = 1.16-26.02) for development of AKI. Age, use of furosemide, and septic shock were predictors of AKI in critically ill patients. Use of furosemide in the subgroup of patients with sepsis/septic shock increased (68.4%) the chance of development of AKI when compared to the sample as a whole (43.9%).
Subject(s)
Acute Kidney Injury/chemically induced , Diuretics/adverse effects , Furosemide/adverse effects , Shock, Septic/complications , Acute Kidney Injury/complications , Aged , Critical Illness , Female , Humans , Intensive Care Units , Length of Stay , Male , Middle Aged , Prognosis , Risk FactorsABSTRACT
Low severity of GVHD, substantial graft vs tumor (GVT) and slow development of protective immunity are well-documented features of cord blood transplants (CBT). We have evaluated the immune reconstitution of adult recipients of single-unit CBT supported by the coinfusion of third party donor (TPD) mobilized hematopoietic stem cells (MHSC), a procedure-'dual CB/TPD-MHSC transplant'-that results in early recovery of circulating granulocytes, high rates of CB engraftment and full chimerism. Cumulative recovery of natural killer and B cells at or above the median values of normal controls were 1.0 and 0.76 by the sixth and ninth months. Recovery of T cells was much slower, naive cells lagging behind those of memory and effector (committed) immunophenotypes. Serial analyses of signal joint TCR excision circles showed a general pattern of very low levels by the third month after CBT, followed by recovery to levels persistently similar or higher than those observed before transplantation and in normal controls. Our results are consistent with the clinical observations of substantial GVT effect together with low incidence of serious GVHD and slow development of protective immunity and suggest that thymic function contributes substantially to the recovery of T-cell populations in adults receiving dual CB/TPD-MHSC transplants.
Subject(s)
Cord Blood Stem Cell Transplantation/methods , Hematologic Neoplasms/surgery , Hematopoietic Stem Cell Transplantation/methods , Adult , Disease-Free Survival , Female , Graft Survival/immunology , Graft vs Host Disease/immunology , Hematologic Neoplasms/immunology , Hematopoietic Stem Cell Mobilization , Histocompatibility Testing , Humans , Kaplan-Meier Estimate , Living Donors , Lymphocyte Activation/immunology , Male , Middle Aged , Transplantation Conditioning , Transplantation Immunology , Young AdultABSTRACT
This open label clinical study provides updated evaluation of the strategy of single unit cord blood transplants (CBTs) with co-infusion of third-party donor (TPD) mobilized hematopoietic stem cells (MHSC). Fifty-five adults with high-risk hematological malignancies, median age 34 years (16-60 years) and weight 70 kg (43-95 kg), received CBTs (median 2.39 x 10(7) total nucleated cell (TNC) per kg and 0.11 x 10(6) CD34+ per kg) and TPD-MHSC (median 2.4 x 10(6) CD34+ per kg and 3.2 x 10(3) CD3+ per kg). Median time to ANC and to CB-ANC >0.5 x 10(9)/l as well as to full CB-chimerism was 10, 21 and 44 days, with maximum cumulative incidences (MCI) of 0.96, 0.95 and 0.91. Median time to unsupported platelets >20 x 10(9)/l was 32 days (MCI 0.78). MCI for grades I-IV and III-IV acute GVHD (aGVHD) were 0.62 and 0.11; 12 of 41 patients (29%) who are at risk developed chronic GVHD, becoming severely extensive in three patients. Relapses occurred in seven patients (MCI=0.17). The main causes of morbi-mortality were post-engraftment infections. CMV reactivations were the most frequent, their incidence declining after the fourth month. Five-year overall survival and disease-free survival (Kaplan-Meier) were 56 % and 47% (63% and 54% for patients Subject(s)
Cord Blood Stem Cell Transplantation
, Hematopoietic Stem Cell Transplantation
, Tissue Donors
, Adolescent
, Adult
, Cord Blood Stem Cell Transplantation/adverse effects
, Cord Blood Stem Cell Transplantation/mortality
, Female
, Graft vs Host Disease/etiology
, Hematopoietic Stem Cell Mobilization
, Hematopoietic Stem Cell Transplantation/adverse effects
, Hematopoietic Stem Cell Transplantation/mortality
, Histocompatibility Testing
, Humans
, Male
, Middle Aged
Subject(s)
Chagas Disease/transmission , Cord Blood Stem Cell Transplantation/adverse effects , Leukemia, Myeloid/therapy , Adult , Benzimidazoles/therapeutic use , Chagas Disease/drug therapy , Fatal Outcome , Graft vs Host Disease/prevention & control , Humans , Immunosuppressive Agents/therapeutic use , MaleABSTRACT
El anticuerpo monoclonal humano H24 fue obtenido de un ratón transgénico portador de los genes para IgM/kappa/lambda humanos, tras ser inmunizado con la línea celular humana U937. H24 es un anticuerpo completamente humano de isotipo IgM/lambda que reconoce específicamente a una proteína de 80 kDa expresada en granulocitos y monocitos humanos, pero ausente en linfocitos en reposo, hematíes, plaquetas o células progenitoras de médula ósea. El anticuerpo monoclonal H24 reconoce a todas las leucemias mieloides (tanto agudas como crónicas) y síndromes mielodisplásicos analizados, siendo capaz de lisar específicamente a las células en presencia de complemento de conejo. Es interesante destacar que H24 no reconoce leucemias de células B tanto agudas, como linfocíticas crónicas o de células plasmáticas, pero sin embargo se une a células de nódulo linfoide de pacientes con linfoma no Hodgking (NHL) CD5-. Así, este anticuerpo parece ser específico de granulocitos, monocitos y células CD5- de NHL, lo que le hace ser un candidato de potencial utilidad clínica en el tratamiento de procesos linfoproliferativos malignos como leucemias mieloides y algunos linfomas no Hodgking (AU)
Subject(s)
Animals , Mice , Antibodies, Monoclonal/immunology , CD5 Antigens/immunology , Lymphoma, Non-Hodgkin/immunology , Lymphoproliferative Disorders/immunology , Mice, Transgenic/immunology , Flow Cytometry , Enzyme-Linked Immunosorbent AssayABSTRACT
Here we compare human monoclonal antibody (MAb) production from mouse strains that carry disruptions of their endogenous mouse IgH/IgK loci and harbor human IgM + Igkappa(BABkappa) or human IgM + Igkappa + IgA transloci (BABkappa,lambda). We found that whereas both strains proved effective for the isolation of antigen-specific IgM antibodies, many of the IgM MAbs elicited from BABkappa comprise human mu chains that are associated with mouse lambda chains. In contrast, BABkappa,lambda mice gave rise to fully functional, polymeric human IgM antibodies comprising both human IgH and human IgL chains. Therefore, the inclusion of a human Iglambda translocus (in addition to the human IgH + Igkappa transloci) not only diminishes problems of endogenous mouse Iglambda expression but also provides a strain of mice that yields fully human MAbs to a wide range of antigens, as witnessed by the isolation of MAbs to human blood cells, tumor cell lines, and an immunoglobulin idiotype.
Subject(s)
Antibodies, Monoclonal/biosynthesis , Antibodies, Monoclonal/genetics , Immunoglobulin M/biosynthesis , Immunoglobulin M/genetics , Immunoglobulin kappa-Chains/biosynthesis , Immunoglobulin kappa-Chains/genetics , Animals , Antibodies, Monoclonal/immunology , Gene Expression Regulation/immunology , Humans , Hybridomas/immunology , Hybridomas/physiology , Immunoglobulin M/immunology , Immunoglobulin kappa-Chains/immunology , Mice , Mice, Mutant Strains , Mice, Transgenic , Monocytes/immunology , Monocytes/physiology , Reproducibility of Results , Sensitivity and Specificity , Species Specificity , Spleen/immunologyABSTRACT
Intravenous infusion of gammaglobulins (IVIG) is one of the treatments of choice in patients with type II mixed cryoglobulinemia (MC). We describe the case of a patient with MC who suffered an adverse generalised reaction with severe cutaneous vasculitis accompanied by a sudden increase in cryocrit levels shortly after being treated with IVIG. When the same gammaglobulin preparation was added in vitro to a sample of the patient's serum, a strong increment in cryoglobulin precipitation and depletion of the monoclonal IgM peak resulted. We suggest that this simple method of studying the displacement of the precipitation reaction could help to predict the outcome of treatment and must be performed before starting IVIG in patients with MC.
Subject(s)
Cryoglobulinemia/therapy , Immunoglobulins, Intravenous/adverse effects , Vasculitis, Leukocytoclastic, Cutaneous/etiology , Adult , Female , Humans , Immunoglobulins, Intravenous/therapeutic useABSTRACT
The number of infused cells is a very important factor in cord blood transplant (CBT) engraftment. Prior ex vivo expansion of aliquots of transplanted cord blood (CB) units is being investigated as a procedure to increase engraftment potential, but results are difficult to evaluate due to a lack of markers for assessing the contribution of expanded cells. We transplanted five patients, infusing the best available CB unit and cells from a second donor simultaneously. In two patients, these cells were obtained from another frozen CB unit by CD34(+)positive selection and culture expansion; the other three patients received uncultured highly purified haploidentical CD34(+) cells. The first two patients had DNA from the culture expanded CB cells detected only for a few days around day +11 when the absolute neutrophil count (ANC) was >200/microl; thereafter and when the ANC was <500/microl, only donor DNA from the uncultured CB was detected. For the other three patients, DNA analysis showed early and transient granulocyte engraftment of haploidentical cells, progressively replaced by the CB-derived granulocytes. We concluded that: (1) simultaneous infusion of lymphocyte-depleted HLA highly mismatched haematopoietic progenitor cells has not produced unfavourable effects for CBT; (2) the double transplant model is suitable for evaluating the engraftment potential of ex vivocultured CB cells in the clinical setting; (3) the culture conditions used did not result in early recovery of ANC; and (4) co-transplantation of purified uncultured HLA haploidentical CD34(+) cells may reduce the time of neutropenia following CBT.
Subject(s)
Fetal Blood/cytology , Graft Rejection/genetics , Haplotypes/genetics , Hematopoietic Stem Cell Transplantation/methods , Neutrophils/cytology , Neutrophils/metabolism , Nuclear Family , Polymorphism, Genetic/genetics , Acute Disease , Adult , Cell Separation/methods , Cells, Cultured , Female , Graft Rejection/immunology , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Leukemia, Myeloid/genetics , Leukemia, Myeloid/therapy , Male , Middle Aged , Transplantation Chimera/geneticsABSTRACT
One of the central questions in developmental biology is that of how one cell can give rise to all specialized cell types and organs in the organism. Within the embryo, all tissues are composed of cells derived from one or more of the three germ layers, the ectoderm, the mesoderm, and the endoderm. Understanding the molecular events that underlie both the specification and patterning of the germ layers has been a long-standing interest for developmental biologists. Recent years have seen a rapid advancement in the elucidation of the molecular players implicated in patterning the vertebrate embryo. In this review, we will focus solely on the ventral and posterior fate acquisition in the ventral-lateral domains of the pregastrula embryo. We will address the embryonic origins of various tissues and will present embryological and experimental evidence to illustrate how "classically defined" ventral and posterior structures develop in all three germ layers. We will discuss the status of our current knowledge by focusing on the African frog Xenopus laevis, although we will also gather evidence from other vertebrates, where available. In particular, genetic studies in the zebrafish and mouse have been very informative in addressing the requirement for individual genes in these processes. The amphibian system has enjoyed great interest since the early days of experimental embryology, and constitutes the best understood system in terms of early patterning signals and axis specification. We want to draw interest to the embryological origins of cells that will develop into what we have collectively termed "posterior" and "ventral" cells/tissues, and we will address the involvement of the major signaling pathways implicated in posterior/ventral fate specification. Particular emphasis is given as to how these signaling pathways are integrated during early development for the specification of posterior and ventral fates.
Subject(s)
Embryonic and Fetal Development , Activins , Animals , Endoderm/physiology , Fibroblast Growth Factors/physiology , Humans , Inhibins/physiology , Mesoderm/physiologyABSTRACT
Fibroblast growth factor homologous factors (FHFs) have been implicated in limb and nervous system development. In this paper we describe the expression of the cFHF-4 gene during chicken craniofacial development. cFHF-4 is expressed in the mesenchyme of the frontonasal process, and in the mesenchyme and ectoderm of the mandibular processes. The expression of cFHF-4 and other genes implicated in facial patterning have been analyzed in talpid(2) embryos or in the presence of exogenous retinoic acid. Talpid(2) mutants show abnormal patterns of gene expression, including up-regulation of cFHF-4 in the developing face, which correlate with defects in cartilage formation. By contrast, expression of cFHF-4 in the developing face is strongly downregulated by teratogenic doses of all-trans retinoic acid in a dose-dependent manner. Low levels of retinoic acid that produce distal upper beak truncations do not affect cShh, c-Patched-1, or c-Bmp-2 expression in the face, but downregulate cFHF-4 in the frontonasal process.
Subject(s)
Facial Bones/embryology , Fibroblast Growth Factors/genetics , Skull/embryology , Animals , Chick Embryo , Craniofacial Abnormalities/embryology , Craniofacial Abnormalities/genetics , Craniofacial Abnormalities/metabolism , Facial Bones/metabolism , Gene Expression Regulation, Developmental/drug effects , In Situ Hybridization , Mutation , Signal Transduction , Skull/metabolism , Tretinoin/metabolism , Tretinoin/pharmacologyABSTRACT
Fibroblast growth factor homologous factors (FHFs) have been implicated in limb and nervous system development. In this paper we describe the expression of the cFHF-4 gene during early chicken development. cFHF-4 is expressed in the paraxial mesoderm, lateral ridge, and, most prominently, in the posterior-dorsal side of the base of each limb bud. The expression pattern of cFHF-4 at the base of the limbs is not altered by tissue grafts containing the zone of polarizing activity (ZPA), by implants of Shh-expressing cells, or by implants of beads containing retinoic acid, nor does it depend on the distal growth of the limb as it is not altered in limb buds that are surgically truncated. In three chicken mutants affecting limb patterning - talpid(2), limbless, and wingless - altered patterns of cFHF-4 expression are correlated with abnormal nerve plexus formation and altered patterns of limb bud innervation. Similarly, ectopic expression of cFHF-4 is correlated with a local induction of limb-like innervation patterns when beads containing FGF-2 are implanted in the flank. In these experiments, both ectopic innervation and ectopic expression of cFHF-4 in the flank were observed regardless of the size of the FGF-2-induced outgrowths. By contrast, ectopic expression of Shh and HoxD13 are seen only in the larger FGF-2-induced outgrowths. Taken together, these data suggest that cFHF-4 regulates or is coregulated with early events related to innervation at the base of the limbs.
Subject(s)
Embryo, Nonmammalian/embryology , Extremities/embryology , Fibroblast Growth Factors/physiology , Gene Expression Regulation, Developmental , Animals , Chick Embryo , Embryo, Nonmammalian/physiology , Extremities/physiologyABSTRACT
A 48-year-old patient with IgA k multiple myeloma received a BMT from his HLA-matched sibling. After transplantation, the disease relapsed. Melphalan therapy followed by reinfusion of haemopoietic blood stem cells collected from the patient led to the improvement of the clinical status, although mixed chimerism and an elevated serum IgA persisted. Successful donor immunisation against an immunogenic preparation of the recipient monoclonal protein was performed before the infusion of donor T lymphocytes (DLI) into the patient. Ten weeks after the lymphocyte infusions, no monoclonal band was evidenced and donor complete chimerism was detected. The patient did not develop GVHD. Once complete remission was achieved, the idiotype vaccine was administered to the patient. Nineteen months after DLI, the patient remains in remission. Bone Marrow Transplantation (2000).
Subject(s)
Blood Donors , Immunization , Immunoglobulin A/immunology , Immunoglobulin Idiotypes/immunology , Immunoglobulin kappa-Chains/immunology , Immunotherapy, Adoptive , Lymphocyte Transfusion , Multiple Myeloma/therapy , Myeloma Proteins/immunology , Salvage Therapy , T-Lymphocytes/transplantation , Antineoplastic Agents, Alkylating/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Marrow Transplantation , Chimera , Combined Modality Therapy , Dexamethasone/administration & dosage , Doxorubicin/administration & dosage , Graft Survival , Humans , Male , Melphalan/therapeutic use , Middle Aged , Multiple Myeloma/drug therapy , Multiple Myeloma/immunology , Remission Induction , Vincristine/administration & dosageABSTRACT
Fibroblast growth factor (FGF) homologous factors-1, -2, -3, and -4 (FHFs 1-4; also referred to as FGFs 11-14) comprise a separate branch of the FGF family and have been implicated in the development of the nervous system and limbs. We report here the characterization of multiple isoforms of FHF-1, -2, -3, and -4 which are generated through the use of alternative start sites of transcription and splicing of one or more of a series of alternative 5'-exons. Several isoforms show different subcellular distributions when expressed in transfected tissue culture cells, and the corresponding differentially spliced transcripts show distinct expression patterns in developing and adult mouse tissues. Together with the evolutionary conservation of the FHF isoforms among human, mouse, and chicken, these data indicate that alternative promoter use and differential splicing are important regulatory processes in controlling the activities of this subfamily of FGFs.
Subject(s)
Alternative Splicing , Fibroblast Growth Factors/genetics , Growth Substances/genetics , Promoter Regions, Genetic , Protein Isoforms/genetics , Amino Acid Sequence , Animals , Base Sequence , DNA Primers , Gene Expression Regulation, Developmental , Growth Substances/metabolism , Humans , In Situ Hybridization , Mice , Molecular Sequence Data , Sequence Homology, Amino Acid , Subcellular Fractions/metabolismABSTRACT
PURPOSE: To detect and quantify by flow cytometry (FC) PNH clones in paroxysmal nocturnal haemoglobinuria (PNH) and aplastic anaemia (AA) patients. PATIENTS AND METHODS: We have performed a flow cytometric analysis to determine the granulocyte expression of CD55 and CD59 from 29 patients with AA and 11 patients with PNH. RESULTS: In the 11 PNH patients the study showed 58 +/- 34% and 56 +/- 32% (mean +/- SD) CD55(-) y CD59(-) granulocytes. A good correlation was found between the results of FC and haemolysis. The follow-up study showed PNH clone progression in one case and stability in 5 cases. Among 11 AA patients studied at diagnosis, two presented a population of CD55(-) granulocytes (14% and 48%) with CD59 normal, this defect disappeared in both patients after immunosuppressive therapy. The FC study revealed PNH clones in 7 cases among the 26 analyzed after treatment (23 with ATG and/or CyA), in 3 cases with negative Ham's test (in two this became positive 6 and 12 months later). The mean values obtained in these 7 patients with PNH-AA syndrome were 26 +/- 15% y 36 +/- 30% (mean +/- SD) CD55(-) and CD59(-) granulocytes. The median time from diagnosis to detection of PNH phenomenon was 83 months. In the follow-up study, 4 cases had stability, one case had a decrease and one a progression of the abnormal clone. In a retrospective analysis, among the 7 patients with PNH-AA syndrome, 5 had a partial response after the initial treatment. CONCLUSIONS: The FC on granulocytes is a useful method to diagnose and characterize PNH. This test is good for early detection of PNH clones in AA patients at initial diagnosis and in long term survivors. In both diseases it permits measuring the extent of the abnormal clone and its follow up. The extent of the defect is more related to haemolysis than the haematopoietic deficiency. PNH development seems to be more frequent in AA patients with incomplete response after immunosuppressive therapy and in some cases the defect could be latent at the time of diagnosis.
Subject(s)
CD55 Antigens/analysis , CD59 Antigens/analysis , Clone Cells/pathology , Flow Cytometry , Granulocytes/pathology , Hemoglobinuria, Paroxysmal/blood , Adult , Anemia, Aplastic/blood , Anemia, Aplastic/etiology , Anemia, Aplastic/pathology , Antilymphocyte Serum/therapeutic use , Cyclosporine/therapeutic use , Female , Hemoglobinuria , Hemoglobinuria, Paroxysmal/complications , Hemoglobinuria, Paroxysmal/drug therapy , Hemoglobinuria, Paroxysmal/pathology , Hemolysis , Humans , Immunosuppressive Agents/therapeutic use , Male , Middle Aged , T-LymphocytesABSTRACT
Members of the fibroblast growth factor (FGF) family have been identified as signaling molecules in a variety of developmental processes, including important roles in limb bud initiation, growth and patterning. This paper reports the cloning and characterization of the chicken orthologues of fibroblast growth factor homologous factors-1 and -2 (cFHF-1/cFGF-12 and cFHF-2/cFGF-13, respectively). We also describe the identification of a novel, conserved isoform of FHF-2 in chickens and mammals. This isoform arises by alternative splicing of the first exon of the FHF-2 gene and is predicted to encode a polypeptide with a distinct amino-terminus. Whole-mount in situ hybridization reveals restricted domains of expression of cFHF-1 and cFHF-2 in the developing neural tube, peripheral sensory ganglia and limb buds, and shows that the two cFHF-2 transcript isoforms are present in non-overlapping spatial distributions in the neural tube and adjacent structures. In the developing limbs, cFHF-1 is confined to the posterior mesoderm in an area that encompasses the zone of polarizing activity and cFHF-2 is confined to the distal anterior mesoderm in a region that largely overlaps the progress zone. Ectopic cFHF-2 expression is induced adjacent to grafts of cells expressing Sonic Hedgehog and the zone of cFHF-2 expression is expanded in talpid2 embryos. In the absence of the apical ectodermal ridge or in wingless or limbless mutant embryos, expression of cFHF-1 and cFHF-2 is lost from the limb bud. A role for cFHF-2 in the patterning and growth of skeletal elements is implied by the observation that engraftment of developing limb buds with QT6 cells expressing a cFHF-2 isoform that is normally expressed in the limb leads to a variety of morphological defects. Finally, we show that a secreted version of cFHF-2 activates the expression of HoxD13, HoxD11, Fgf-4 and BMP-2 ectopically, consistent with cFHF-2 playing a role in anterior-posterior patterning of the limb.
Subject(s)
Alternative Splicing/genetics , Extremities/growth & development , Fibroblast Growth Factor 2/genetics , Fibroblast Growth Factors , Gene Expression Regulation, Developmental/genetics , Growth Substances/genetics , Peptides , Trans-Activators , Amino Acid Sequence , Animals , Bone Morphogenetic Proteins/genetics , Chick Embryo , Cloning, Molecular , Extremities/embryology , Fibroblast Growth Factor 1 , Genes, Homeobox/genetics , Growth Substances/chemistry , Hedgehog Proteins , In Situ Hybridization , Limb Deformities, Congenital/genetics , Molecular Sequence Data , Mutation/genetics , Proteins/genetics , RNA, Messenger/analysis , Sequence Homology, Amino Acid , Tissue TransplantationABSTRACT
Epstein-Barr virus associated lymphoproliferative disease after autologous bone marrow transplantation (ABMT) has rarely been reported. We report a case of B-cell lymphoma following ABMT for T-acute lymphoblastic leukaemia; bone marrow was purged in vitro with monoclonal antibodies to remove T cells. Immunoglobulin and T-cell receptor gene rearrangement studies were used to demonstrate clonality and to show that this patient developed a second neoplasm after ABMT. EBV proteins and genome (type A) were present in post-transplantation lymphoma, suggesting a causative role in its development.