Analysis and comparison of clinicohematological parameters and molecular and cytogenetic response of two Bcr/Abl fusion transcripts

Different forms of p210 are produced by alternative splicing, namely b2a2 and b3a2. There have been many contrasting data establishing a relationship between the two Bcr/Abl transcripts and platelet counts and also response to treatment. However, the data published to date have been on a small group of patients. The aim of the present study was to determine whether there was any difference between clinical and hematological parameters at diagnosis between the two Bcr/Abl fusion transcripts in our population, and whether the two transcripts responded differently or similarly to imatinib treatment. RT-PCR was performed in 202 cases for detection of Bcr/Abl transcripts in newly diagnosed chronic myelogenous leukemia cases in one year. The two transcripts were compared and correlated with clinical, hematological and FISH data and with response to treatment. A total of 138 cases were of b3a2 and 64 were of b2a2 transcript. There was no correlation between the hematological parameters and the type of transcript. There was a significant association of blast crisis with b2a2, especially with myeloid blast crisis. When compared to FISH results, 10% of b3a2 were found to have a significant association with 5'Abl deletion as compared to 3% of b2a2. On analyzing the therapeutic response, we did not find any difference between the two transcripts. In conclusion, our findings confirm that the b3a2 type transcript is not significantly associated with thrombocytosis, that the short transcript, b2a2, occurs with acute phase, i.e., blast crisis, and that there is no difference in treatment response between the two transcripts. However, further studies are required to understand the molecular pathways involved in the Bcr/Abl mechanism.

Role of different valence states of chromium in the elicitation of allergic contact dermatitis

Chromium, a known contact sensitizer, is present at high levels in certain detergent bars (40-50 p.p.m.) sold in India. A concern was whether chromium present in such detergent bars could sensitize users or their use lead to the elicitation of allergic contact dermatitis. Chromium present in detergent bars was analyzed for its valence state. It was found to be trivalent [Cr (III)] and not hexavalent [Cr (VI)]. An elicitation test on normal volunteers, as well as on volunteers who were sensitive to chromium, was carried out to determine the elicitation potential of chromium (III) in the bars. Of the 48 volunteers who completed the study, 30 did not show any positive response to either potassium dichromate, the positive control, or the detergent bar containing chromium (III). 18 volunteers who were identified as chromium-sensitive showed a positive response to potassium dichromate but not to the detergent bar containing trivalent chromium. This study clearly showed that the detergent bar with 40-50 p.p.m. of trivalent chromium did not elicit any allergic contact dermatitis even in individuals known to be chromium-sensitive. Hexavalent chromium (potassium dichromate) did however, elicit allergic contact dermatitis in these subjects.

Susceptibility of diamond back moth, Plutella xylostella (L) to entomopathogenic nematodes

Eight entomopathogenic nematode species / strains, Steinernema glaseri (steiner), S. carpocapsae (Weiser), S. feltiae (Filipjev), Steinernema sp. Ecomax strain, Heterorhabditis bacteriophora (Pioner), Heterorhabditis sp. Ecomax strain, two locally isolated strains called as JFC and TFC were tested against the final instar larvae of diamond back moth, Plutella xylostella (L.). All nematodes were found pathogenic. However, H. bacteriophora was adjudged the most pathogenic amongst the test nematodes on the basis of LD50 (9.16 IJS/larva), LT50 (43.26 hr), Lex T50 (3.24 hr) and the propagation potential (average of 271.42 IJS/mg) on the host body weight.

The past, present, and future of direct-to-consumer prescription drug advertising

Since the first experiences with direct-to-consumer (DTC) prescription drug advertising in the early 1980s, pharmaceutical marketers, government regulators, researchers, health practitioners, and consumers have been both perplexed and intrigued by this practice. As experience with DTC advertising has expanded, so has knowledge and understanding of its risks and rewards. This article discusses important issues in DTC advertising, such as the effects it may have on the patient-practitioner relationship, the diffusion and adoption of new drugs, prices, and competition. It also discusses the future of DTC advertising.

T cell autoimmunity in Ig transgenic mice

Autoantibodies directed at a diverse group of proteins of the U1/Sm ribonucleoprotein (snRNP) are characteristic of systemic lupus erythematosus and are found in the MRL murine model of this disease. This study examines the role of transgenic B lymphocytes in the regulation of autoreactive T cells to the snRNP autoantigen. Transgenic mice were developed bearing an Ig heavy chain gene specific for the D protein component of murine snRNP. B lymphocytes in these mice are neither deleted nor anergic and are of an immature (heat-stable Aghigh) phenotype. T lymphocytes from anti-snRNP transgenic mice were examined using a recombinant form of the D protein of the murine snRNP complex. Our results revealed that transgenic anti-snRNP B cell APCs stimulated CD4 T cells from wild-type C57BL/6 and MRL lpr/lpr mice, while nonspecific APCs failed to stimulate CD4 T cells. This study demonstrates that autoreactive T cells are not deleted from wild-type mice, although their activation is facilitated by autoantigen-specific APCs. The snRNP-reactive T cells in C57BL/6 transgenic mice are tolerized, in contrast to those T cells from MRL lpr/lpr transgenic mice. These studies implicate a role for autoreactive B lymphocytes in the in vivo activation and/or diversification of autoreactive T cells.

Retroperitoneal extraosseous osteosarcoma. A case report and review of literature

Extraosseous osteogenic sarcoma is a rare and highly malignant neoplasm. A 57 year old male patient presented with a mass in the abdomen involving the left lumber region. The ultrasound and computerized tomography (CT) scan showed a large mass arising from upper pole of the left kidney. Left radical nephrectomy was performed in April 1995. Histopathology report revealed a high grade extraosseous osteogenic sarcoma. Patient was disease free for 23 months. Although the prognosis is grave, aggressive surgical treatment with adjuvant therapy helps in prolonging the survival.

Sezary cells with hairy projections

A case of sezary syndrome where the sezary cells showed cytoplasmic hairy projections is reported. The patient had typical exfoliative erythematous dermatitis, high white cell count, atypical lymphocytes of T-phenotype with folded nuclei and bone marrow involvement. The ultra structure study showed cerebriform nucleus and cytoplasmic projections.

Ultrastructural, cell culture and karyotype study of bone marrow in a patient with congenital dyserythropoietic anaemia (CDA)-type III presenting with recurrent still-births

A 28 year old female patients presented with refractory anaemia since childhood and recurrent still-births at 28-30 weeks of gestation. One still-born child was hydropic at birth. Bone marrow showed characteristic morphological changes of congenital dyserythropoietic anaemia (CDA)-Type III. Electron microscopy showed disruption of the nuclear membrane, spongy appearance of nuclei, stacks of microtubules in intermediate normoblasts and myelin figures in erythroid cells. In vitro culture and karyotype data from the bone marrow of the patient is presented. Recurrent still-births in association with congenital dyserythropoietic anaemia has rarely been reported in the literature.

CD40L is important for induction of, but not response to, costimulatory activity. ICAM-1 as the second costimulatory molecule rapidly up-regulated by CD40L

The CD40 ligand (CD40L):CD40 interaction plays an important role in the activation of both T and B cells. However, the mechanisms by which this interaction is involved in activation of T cells is still unclear. Here we show that CD40L is not essential for T cell response to TCR engagement if the APC have costimulatory activity, although it is essential for T cell-mediated induction of such costimulatory activity. To determine the molecular basis of this activity, we have produced three mAbs that appear to recognize the costimulatory molecules rapidly induced by CD40L. Two of them recognize CD44H, which we showed to have CD28-independent costimulatory activity for T cells. The molecule recognized by the remaining mAb is hereby identified as ICAM-1. Furthermore, ICAM-1-mediated costimulation is likely to serve for a function similar to that mediated by the B7:CD28 interaction, as targeted mutation of CD28 renders T cell responses to Con A more dependent on ICAM-1.

CD40L is important for induction of, but not response to, costimulatory activity. ICAM-1 as the second costimulatory molecule rapidly up-regulated by CD40L

The CD40 ligand (CD40L):CD40 interaction plays an important role in the activation of both T and B cells. However, the mechanisms by which this interaction is involved in activation of T cells is still unclear. Here we show that CD40L is not essential for T cell response to TCR engagement if the APC have costimulatory activity, although it is essential for T cell-mediated induction of such costimulatory activity. To determine the molecular basis of this activity, we have produced three mAbs that appear to recognize the costimulatory molecules rapidly induced by CD40L. Two of them recognize CD44H, which we showed to have CD28-independent costimulatory activity for T cells. The molecule recognized by the remaining mAb is hereby identified as ICAM-1. Furthermore, ICAM-1-mediated costimulation is likely to serve for a function similar to that mediated by the B7:CD28 interaction, as targeted mutation of CD28 renders T cell responses to Con A more dependent on ICAM-1.

Identification of a costimulatory molecule rapidly induced by CD40L as CD44H

The interaction between CD40 ligand and CD40 is critical for activation of T and B cells in vivo. We have recently demonstrated that this interaction rapidly induces a novel costimulatory activity distinct from B7 and independent of CD28. To study the molecular basis of the costimulatory activity, we have produced a novel monoclonal antibody, TM-1, that binds an 85-kilodalton costimulatory molecule rapidly induced by CD40L. Expression cloning reveals that TM-1 binds CD44H. CD44H expressed on Chinese hamster ovary cells has potent costimulatory activity for clonal expansion of T cells isolated from both wild-type mice and these with a targeted mutation of CD28. Thus, CD44H costimulates T cell proliferation by a CD28-independent mechanism. These results revealed that CD44H is a costimulatory molecule rapidly induced by CD40L.

Rapid induction of a novel costimulatory activity on B cells by CD40 ligand

BACKGROUND

T cells and B cells communicate by direct cell--cell interaction that is crucial to the functioning of the immune system. It is well established that the interaction between B-cell-expressed CD40 and T-cell-expressed CD40 ligand (CD40L) is critical for T-cell-dependent antibody responses, but the role of this interaction in T-cell responses is less clear. In this study, we have used mice with targeted mutations in the genes encoding CD40L or CD28 to investigate how the CD40-CD40L interaction induces on B cells a costimulatory activity that acts in addition to antigen to trigger T-cell growth.

RESULTS

We show that T cells from Cd40L-deficient mice induce a substantially reduced costimulatory activity on B cells compared to wild-type T cells, particularly at early time points. Surprisingly, T cells, from CD40L-deficient mice induce similar levels of B7-1 and B7-2 as do wild-type T cells. We further show that the CD40L-mediated induction of costimulatory activity precedes the induction of B7-1, B7-2 and the heat-stable antigen (HSA). CD4 T cells isolated from the CD28-deficient mice can receive costimulatory activity from CD40L-induced B cells, demonstrating that the induced molecules can costimulate T cells by a CD28-independent mechanism. We have generated a novel monoclonal antibody that inhibits the CD40L-induced costimulatory activity. Expression of the epitope detected by this monoclonal antibody correlates with the induction of the costimulatory activity, and the molecule recognized by the monoclonal antibody is a single chain of around 85 kDa, distinct from B7-1, B7-2, ICAM-1, ICAM-2, ICAM-3, HSA CD5, integrin and 4-1BB ligand.

CONCLUSIONS

Our results demonstrate that CD40L is both necessary and sufficient for rapid, T-cell-mediated induction of costimulatory activity on B cells. This costimulatory activity is distinct from B7-1 and B7-2, and is independent of CD28.

Immunophenotype and ultrastructural studies in blast crisis of chronic myeloid leukemia

Thirty-four patients with chronic myeloid leukemia in blast crisis (CML-BC) were evaluated for lineage differentiation with immunological markers and the presence of ultrastructural peroxidase. Eighteen (52.9%) were found to have myeloid blast crisis. Cytochemically, myeloperoxidase (MPO) could be detected only in six patients on light microscopy while in the remaining 12 patients, myeloid differentiation was confirmed only by demonstration of MPO either at ultrastructural level or by the reactivity with anti myeloperoxidase (anti MPO) antibody. Six (17.6%) had lymphoid blast crisis as identified by lymphoid specific markers (CD19; CD10; CD7; CD4) along with the absence of myeloid markers. Heterogenous blast cell populations with mixed lineage differentiation were seen in 4 (11.7%) patients. These cases showed both lymphoid (CD19, CD10) and myeloid (anti MPO and ultrastructural MPO) characteristics. A single case of megakaryoblastic blast crisis was identified with positivity for CD41 and CD42 along with the presence of platelet peroxidase at the ultrastructural level. Five cases (14%) of CML blast crisis remained unclassifiable. These results suggest that blast crisis in CML show an arrest of differentiation at an early stage when compared to de novo acute leukemias. This is particularly evident from the fact that MPO could only be demonstrated ultrastructurally or with anti MPO antibody in the majority of patients with myeloid differentiation. It is expected that utilisation of molecular studies including immunoglobulin and T-cell receptor gene rearrangement and m-RNA expression for myeloperoxidase will provide a better insight into the level of differentiation for the presently unclassifiable cases of CML-blast crisis.

Selective processing of exogenous antigens by antigen-presenting cells with deleted MHC genes

Recently, APCs expressing genes for the alpha- and beta-chains of MHC class II, but not other proteins encoded in the MHC class II locus, have been found to be defective in processing proteins by the MHC class II Ag presentation pathway. Ag presentation of hen egg OVA has been examined in one of these cell lines, T2.Ak. OVA was processed normally by T2.Ak when compared with OVA processed by T1.Ak, a cell line that expresses the MHC genes missing in T2.Ak. By contrast, native hen egg lysozyme (HEL) was not presented as Ag by T2.Ak, which is in agreement with earlier results. Digestion with thiol proteases is important for Ag processing of HEL. We therefore analyzed the expression of these enzymes in T1.Ak and T2.Ak by using a reagent that specifically radiolabels thiol proteases. In these experiments, the repertoire of proteases expressed in the microsomes of T1.Ak was found to be distinct from the repertoire expressed by T2.Ak. Finally, in in vitro digestion experiments, the group of thiol proteases active in T1.Ak microsomes digested HEL differently from the group identified in T2.Ak. These results provide evidence that the defect in Ag presentation that is encoded by MHC genes and manifests itself in defective processing of HEL is not absolute. Further, the mutation in T2.Ak coincides with altered activities of thiol proteases, a class of enzymes involved in processing exogenous Ags.

Selective processing of exogenous antigens by antigen-presenting cells with deleted MHC genes

Recently, APCs expressing genes for the alpha- and beta-chains of MHC class II, but not other proteins encoded in the MHC class II locus, have been found to be defective in processing proteins by the MHC class II Ag presentation pathway. Ag presentation of hen egg OVA has been examined in one of these cell lines, T2.Ak. OVA was processed normally by T2.Ak when compared with OVA processed by T1.Ak, a cell line that expresses the MHC genes missing in T2.Ak. By contrast, native hen egg lysozyme (HEL) was not presented as Ag by T2.Ak, which is in agreement with earlier results. Digestion with thiol proteases is important for Ag processing of HEL. We therefore analyzed the expression of these enzymes in T1.Ak and T2.Ak by using a reagent that specifically radiolabels thiol proteases. In these experiments, the repertoire of proteases expressed in the microsomes of T1.Ak was found to be distinct from the repertoire expressed by T2.Ak. Finally, in in vitro digestion experiments, the group of thiol proteases active in T1.Ak microsomes digested HEL differently from the group identified in T2.Ak. These results provide evidence that the defect in Ag presentation that is encoded by MHC genes and manifests itself in defective processing of HEL is not absolute. Further, the mutation in T2.Ak coincides with altered activities of thiol proteases, a class of enzymes involved in processing exogenous Ags.

Active management of high-risk pregnancy

Sixty patients with previous stillbirths were given active antepartum, intrapartum and early postnatal care. A majority (75%) had a history of repeated stillbirths, and responsible pathology was detected in 55% of the cases. In the present pregnancy, 90% of the patients suffered complications, each of which was diagnosed and treated. Most of the group were hospitalized. Tests for serial urinary estrogens were done for 75% of the women. Other special assessments of maturity with amniotic fluid, oxytocin challenges and fetal monitoring were carried out in selected cases. After confirming maturity and degree of antepartum stress, labor was induced when appropriate. There was liberal recourse to cesarean section (18.3%), but no maternal mortality. Overall fetal salvage was 75%.

Morphine analgesia and its modification by drugs altering serotonin (5-HT) and dopamine levels in the brain

Morphine analgesia in mice was significantly potentiated by pretreatment with 5-hydroxytryptophan (5-HTP), especially with higher dose of morphine. Morphine analgesia was antagonised by reserpine. With l-dopa it was antogonised when the dose of morphine was minimal but with increased dosage of morphine, there was no significant effect.