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1.
Clin Oncol (R Coll Radiol) ; 33(3): 172-180, 2021 03.
Article in English | MEDLINE | ID: mdl-33214044

ABSTRACT

AIMS: The safety and efficacy of stereotactic body radiotherapy (SBRT) in localised prostate cancer are now established through phase III randomised trials. Its utility in node-positive prostate cancer is restricted due to a lack of controlled studies specifically addressing this subgroup. Herein we report the safety and efficacy of SBRT in this subgroup. MATERIALS AND METHODS: In total, 60 patients treated with SBRT to prostate and pelvis were analysed. All patients received neoadjuvant androgen deprivation therapy for at least 6 months and long-term adjuvant hormonal therapy (70% medical and 30% surgical). All patients were treated with daily image-guided rotational intensity-modulated radiotherapy. The dose delivered to the prostate and gross node was 35-37.5 Gy and 25 Gy in five fractions to the elective pelvic nodal region on alternate days. Acute and late toxicities were graded as per Radiation Therapy Oncology Group common toxicity criteria. RESULTS: Forty-one (68%) patients had a Gleason score ≥8. The median prostate-specific antigen level at diagnosis was 39 ng/ml. Twenty (33%) patients had common iliac nodal uptake on initial prostate-specific membrane antigen positron emission tomography-computed tomography. After the median follow-up of 30 months, no acute or late Radiation Therapy Oncology Group grade ≥3 gastrointestinal toxicity was noted. Acute grade 2 genitourinary and gastrointestinal toxicities were 8.3% and 11.7%, respectively. Late grade 2 genitourinary and gastrointestinal toxicities were 3.3% and 8.3%, respectively. Late grade 3 genitourinary toxicity was seen in two (3.3%) patients. Three-year overall survival and biochemical failure-free survival was 89% and 77%, respectively. CONCLUSION: SBRT to the prostate and pelvis is safe and efficacious in node-positive prostate cancer even with common iliac nodal involvement (stage M1a).


Subject(s)
Prostatic Neoplasms , Radiotherapy, Intensity-Modulated , Androgen Antagonists , Humans , Male , Neoplasm Grading , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/radiotherapy , Radiation Dose Hypofractionation , Radiosurgery/adverse effects , Radiotherapy, Intensity-Modulated/adverse effects , Treatment Outcome
2.
Am J Transplant ; 16(1): 221-34, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26227106

ABSTRACT

We previously described early results of a nonchimeric operational tolerance protocol in human leukocyte antigen (HLA)-identical living donor renal transplants and now update these results. Recipients given alemtuzumab, tacrolimus/MPA with early sirolimus conversion were multiply infused with donor hematopoietic CD34(+) stem cells. Immunosuppression was withdrawn by 24 months. Twelve months later, operational tolerance was confirmed by rejection-free transplant biopsies. Five of the first eight enrollees were initially tolerant 1 year off immunosuppression. Biopsies of three others after total withdrawal showed Banff 1A acute cellular rejection without renal dysfunction. With longer follow-up including 5-year posttransplant biopsies, four of the five tolerant recipients remain without rejection while one developed Banff 1A without renal dysfunction. We now add seven new subjects (two operationally tolerant), and demonstrate time-dependent increases of circulating CD4(+) CD25(+++) CD127(-) FOXP3(+) Tregs versus losses of Tregs in nontolerant subjects (p < 0.001). Gene expression signatures, developed using global RNA expression profiling of sequential whole blood and protocol biopsy samples, were highly associative with operational tolerance as early as 1 year posttransplant. The blood signature was validated by an external Immune Tolerance Network data set. Our approach to nonchimeric operational HLA-identical tolerance reveals association with Treg immunophenotypes and serial gene expression profiles.


Subject(s)
Biomarkers/analysis , HLA Antigens/genetics , HLA Antigens/immunology , Kidney Failure, Chronic/immunology , Kidney Transplantation , Transplantation Chimera/immunology , Transplantation Tolerance/immunology , Adult , Aged , Female , Follow-Up Studies , Gene Expression Profiling , Genomics/methods , Glomerular Filtration Rate , Graft Survival , Histocompatibility , Humans , Immunophenotyping , Kidney Failure, Chronic/genetics , Kidney Failure, Chronic/surgery , Kidney Function Tests , Male , Middle Aged , Prognosis , Retrospective Studies , Risk Factors , Transplantation Chimera/genetics
3.
Tissue Antigens ; 69 Suppl 1: 123-4, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17445184

ABSTRACT

Killer cell immunoglobulin-like receptors (KIR) on natural killer cells mediate killing by recognizing class I presentation of peptides by infected or oncogenic cells. KIR differences in stem cell transplants have been implicated in increased graft vs host disease. Human leukocyte antigen (HLA)-matched-related kidney recipients have the best graft survival as compared to one haplotype-matched recipients. These HLA-identical transplant pairs may be ideal for studying minor HLA antigens and KIR polymorphic differences and their relation to graft function. We have studied KIR polymorphism in recipients and donor pairs of HLA-matched sibling kidney transplants to demonstrate differences in genotype as related to long-term graft function and/or chronic rejection. We employed a KIR genotyping kit (Dynal, Brown Deer, WI), that uses sequence-specific priming by PCR to identify 19 alleles for genotypes in 12 donor/recipient (D/R) pairs at least 1 year posttransplant. There were two pairs that had different alleles in the recipient that were not found in the donor. One pair had different alleles found in the donor that were not present in the recipient. Two pairs had difference in alleles in both the donor and recipient. Seven of the 12 pairs had the same KIR genotype. Eight of the 12 pairs (both donor and recipient) exhibited a haplotype with 2DL2+ and 2DS2+. Four of the 12 exhibited a haplotype 2DL2- and 2DS2-. Three out of four of these recipients had increased creatinine levels and at least one graded rejection episode. One of these three has lost their graft. In conclusion, the genotyping of HLA-matched sibling kidney transplant D/R pairs demonstrates that there may be an association of higher risk for poor graft function when both genotypes lack 2DL2 and 2DS2.


Subject(s)
Graft Survival/genetics , Graft vs Host Disease/etiology , HLA Antigens/genetics , Hematopoietic Stem Cell Transplantation/methods , Receptors, Immunologic/genetics , Genotype , HLA Antigens/metabolism , Hematopoietic Stem Cell Transplantation/mortality , Histocompatibility Testing , Humans , Killer Cells, Natural/immunology , Neoplasm Recurrence, Local/genetics , Receptors, Immunologic/deficiency , Receptors, Immunologic/immunology , Receptors, KIR , Siblings
4.
Transplant Proc ; 37(2): 1375-8, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15848725

ABSTRACT

A number of recent reports in clinical and experimental intestinal transplantation have suggested that the donor lymphocytes present in and around the gastrointestinal system are potent mediators of graft-versus-host (GvH) reactivity and that GvH responses may contribute to posttransplant morbidity. Therefore, we have tested the proliferative and cytotoxic capabilities of gut-associated lymphocytes from cadaveric donors obtained prerevascularization (pre-r) and about 6 hours postrevascularization (post-r) in recipients pretreated with Campath-1H antibody (alemtuzumab). Mixed lymphocyte reactions (MLR) were performed with lymphoid cells isolated from intestinal epithelial mucosa, lamina propria, and lymph nodes. The pre-r lymphocytes responded strongly to both the recipient and third-party alloantigenic stimulating cells. However, similar preparations from the post-r samples responded in MLR at significantly lower levels (P < .01). This post-r decrease in responsiveness was not observed in similar lymphocyte samples obtained from donors of recipients not treated with Campath-1H. Both the pre-r and post-r samples had similar flow cytometric profiles, suggesting that there was no receptor loss in these lymphoid tissues by the short-term 6-hour exposure to Campath-1H given to the recipient. Conversely, in preliminary experiments where the donor were treated with Campath-1H, it was observed that very few lymphocytes could be obtained from intestinal tissues (n = 3). These results suggested that Campath-1H treatment of the recipient could bring about a drastic reduction in an otherwise strong GvH reactivity by the donor intestinal immune cells.


Subject(s)
Antibodies, Monoclonal/immunology , Antibodies, Neoplasm/immunology , Intestinal Mucosa/immunology , Intestines/transplantation , Isoantibodies/immunology , Lymphocytes/immunology , Tissue Donors , Alemtuzumab , Antibodies, Monoclonal, Humanized , Antirheumatic Agents/immunology , Cadaver , Flow Cytometry , Humans , Intestinal Mucosa/transplantation , Lymph Nodes/immunology , Lymphocyte Activation , Lymphocyte Culture Test, Mixed , Lymphocytes/drug effects
9.
Transplantation ; 70(12): 1675-82, 2000 Dec 27.
Article in English | MEDLINE | ID: mdl-11152096

ABSTRACT

BACKGROUND: Even though a number of transplant centers have adopted donor-specific bone marrow cell (DBMC) infusions to enhance donor cell chimerism, to date there has been no direct evidence linking chimerism with tolerance induction in human organ transplant recipients. METHODS: Cells of donor phenotype were isolated 1 year postoperatively from the peripheral blood lymphocytes and iliac crest bone marrow of 11 living-related-donor (LRD) renal transplant recipients, who had received perioperative donor bone marrow cell infusions. These recipient-derived donor (RdD) cells were characterized phenotypically by flow cytometric analysis and functionally as modulators in mixed lymphocyte reaction (MLR) and cell-mediated lympholysis (CML) assays. RESULTS: The yield of RdD cells ranged from 0.1 to O.9% of the starting material with the majority being TcRalphabeta, CD3 positive T cells, a substantial percentage of which coexpressed CD28. At 1 year posttransplant almost 50% of the LRD-kidney/DBMC recipients tested so far exhibited donor-specific unresponsiveness in MLR (7/17) and CML (6/13) reactions and this trend was further enhanced at 23 years. In the recipients with residual positive antidonor immune responses, the RdD cells inhibited recipient antidonor MLR and CML responses significantly more strongly than freshly isolated and similarly treated iliac crest bone marrow cells from the donor. RdD cells also inhibited the MLR of the recipient to third party allogeneic stimulator cells; however, this nonspecific effect was significantly weaker than specific inhibition. We also established long-term bone marrow cultures stimulated every 2 weeks with irradiated alogeneic feeder cells, that had similar functional properties thus possibly providing us with an in vitro correlate the RdD cells. CONCLUSIONS: These results clearly support the notion that the infused donor cells play a positive role in the induction and/or maintenance of transplant tolerance.


Subject(s)
Bone Marrow Transplantation , Chimera/immunology , Kidney Transplantation/immunology , Kidney Transplantation/methods , Bone Marrow Transplantation/immunology , Cell Separation , Cells, Cultured , Cytotoxicity, Immunologic , Graft Survival/immunology , Humans , In Vitro Techniques , Living Donors , Lymphocyte Culture Test, Mixed , Transplantation Tolerance , Transplantation, Homologous
10.
Transplantation ; 70(12): 1752-60, 2000 Dec 27.
Article in English | MEDLINE | ID: mdl-11152108

ABSTRACT

BACKGROUND: The identity of the cells in the human bone marrow that function as effective regulators of in vitro and possibly in vivo cellular immune responses is not well established. METHODS: Cell subpopulations were isolated from cadaver donor vertebral-body bone marrow cells (DBMC) by using immuno-magnetic microbeads and were tested as inhibitors (modulators) in cell-mediated lympholysis (CML) and mixed lymphocyte reaction (MLR) responses of normal peripheral blood lymphocytes stimulated with irradiated cadaver donor spleen cells. RESULTS: Compared with spleen cells as controls, un-irradiated T-cell depleted DBMC inhibited both the MLR and CML responses of allogeneic responder cells in a dose dependent manner (as in our previous reports). The inhibition was also mediated by a number of purified subpopulations including pluripotent CD34+ stem cells, and their CD34 negative early progeny of both lymphoid and myeloid lineages. These included DBMC enriched for non-T-cell lymphoid precursors (NT-LP/DBMC; i.e., DBMC depleted of CD3, CD15, and glycophorin-A positive cells) and DBMC positively selected for CD38+, CD2+, CD5+, and CD1+ lymphoid cells (all were depleted of CD3+ cells) as well as CD33+ (but CD15 negative) myeloid precursors. However, positively selected CD19+ B-cells and CD15+ myeloid cells did not inhibit the MLR and CML responses. The NT-LP/DBMC that had been repeatedly stimulated with irradiated allogeneic peripheral blood lymphocytes caused the strongest inhibition of the MLR and CML responses of the same allogeneic cells with 200 times fewer modulator cells needed than uncultured DBMC (P<0.001). Flow cytometric analysis revealed that majority of cells in these cell lines had become CD3+ TcR-alphabeta+ CD4+ and CD28+ cells. CONCLUSION: A variety of less differentiated cells of various lineages residing in the human bone marrow are immunoregulatory in vitro. Among them, there is at least one subset that can undergo differentiation in vitro into regulatory T cells that can be maintained in long-term cultures.


Subject(s)
Bone Marrow Cells/classification , Bone Marrow Cells/immunology , Bone Marrow Transplantation/immunology , Immunity, Cellular , Isoantigens , Antigens, CD34/immunology , B-Lymphocytes/immunology , Bone Marrow Cells/cytology , Cell Differentiation , Cells, Cultured , Cytotoxicity, Immunologic , Granulocytes/immunology , Hematopoietic Stem Cells/classification , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/immunology , Humans , In Vitro Techniques , Lymphocyte Culture Test, Mixed , T-Lymphocytes/classification , T-Lymphocytes/cytology , T-Lymphocytes/immunology , Tissue Donors , Transplantation Tolerance , Transplantation, Homologous
11.
Transplantation ; 68(8): 1172-80, 1999 Oct 27.
Article in English | MEDLINE | ID: mdl-10551647

ABSTRACT

BACKGROUND: The cascade of immunological effects brought about by donor bone marrow cell (DBMC) infusions to induce allograft acceptance in clinical transplantation is not fully understood. Aside from acting as immune responding and regulatory cells, the infused DBMC also may sensitize the recipient to the donor antigens. METHODS: To analyze this stimulatory activity of DBMC, in vitro mixed lymphocyte cultures (MLC) and cell-mediated lymphocytotoxicity (CML) culture systems analogous to the transplant model with DBMC infusion were used. RESULTS: When responding peripheral blood lymphocytes (PBL) from normal volunteers were placed in culture with suspensions of Ficoll-purified, T cell-depleted, un-irradiated allogeneic DBMC (NT-DBMC), a reaction was seen in both MLC and CML. However, when compared to allogeneic spleen cells as stimulating cells, the responses to NT-DBMC were of markedly lower magnitude and were not seen when the NT-DBMC was irradiated (3000 R). When responding PBL were stimulated with either NT-DBMC that had been previously cultured with irradiated cells from the responders for 1 week (activated NT-DBMC), NT-DBMC further depleted of CD15+ and glycophorin A-positive cells (NT-LP/DBMC), or purified CD34+ and CD2+ DBMC subsets, stronger lymphoproliferative and cytotoxic responses were observed. Moreover, these responses were not abrogated by irradiation of the stimulating DBMC subpopulations. Depletion of antigen-presenting cells by positive selection of CD3+ cells from the responding PBL abrogated MLC and CML reactivity, even when purified NT-LP/DBMC, the most stimulatory cells, were used. This latter observation was in contrast to the responses seen with cultures containing allogeneic stimulating spleen cell populations. This indicated the requirement for indirect alloantigen presentation, i.e., the failure of these DBMC to stimulate by direct alloantigen presentation. NT-DBMC was able to stimulate responding PBL in secondary MLC and CML responses with an equivalent magnitude, irrespective of whether the stimulators were spleen cells or NT-DBMC. Finally, the MLC and CML responses were inhibited by tacrolimus (FK506), mycophenolic acid (MPA), and cyclosporine (CsA) in a dose dependent manner, in contrast to previously observed refractoriness of DBMC preparations to these agents if DBMC was tested as responder cells or in modulatory assays. CONCLUSIONS: These results indicate that DBMC are able to function as effective in vitro stimulators, but only by indirect antigen presentation, and that the immune responses mediated by them can be down-regulated by their own inherent suppressive nature, an effect that can be enhanced by the presence of immunosuppressive drugs.


Subject(s)
Bone Marrow Cells/immunology , Bone Marrow Transplantation , Tissue Donors , Transplantation Conditioning , Antibody Formation/physiology , Bone Marrow Cells/drug effects , Bone Marrow Cells/physiology , Cadaver , Cytotoxicity, Immunologic , Humans , Immunosuppressive Agents/pharmacology , In Vitro Techniques , Lymphocyte Culture Test, Mixed , Lymphocytes/physiology , Organ Transplantation , Spleen/cytology , Transplantation, Homologous
12.
Hum Immunol ; 60(12): 1281-8, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10626743

ABSTRACT

The aims of this study were to assess the effect of donor bone marrow infusion on the reactivity of recipient peripheral blood lymphocytes (PBL) to mitogen and to donor and third-party cells after primary liver allotransplantation and to identify any correlation between altered immunoreactivity and HLA mismatches, occurrence of rejection, and immunosuppression. The immunoreactivity of recipient PBL toward frozen donor splenocytes was evaluated in mixed lymphocyte culture (MLC) (n = 29) and cell-mediated lympholysis (CML) (n = 27) assays in time intervals ranging from 0.7 to 27 months after transplant. Overall, the mean anti-donor MLC stimulation index (SI) fell from 25.6 +/- 5.2 preoperatively to 4.8 +/- 1.7 after transplantation (p < 0.002), with 14 out of 29 (48.3%) patients developing donor-specific MLC hyporeactivity. HLA class II mismatches were significantly associated with recipient post-transplant immune profile (p < 0.05): MLC donor specific hyporesponsiveness was observed in 70%, versus 37% of patients who shared a class II antigen, versus those that did not. Of the control group, 61.1% developed donor-specific nonreactivity versus 27.2% in the donor bone marrow cells (DBMC) group (p = 0.02). Donor-specific CML hyporeactivity was observed after transplantation, independent of DBMC infusion, with mean percentage values of pre- and post-transplant donor-specific lysis of 22.4% +/- 4.1% versus 3.1% +/- 1.6%, p = 0.0004, respectively. Our results suggest that DBMC infusion favors development of nonspecific MLC hyporesponsiveness to donor and third-party alloantigen, with maintenance of reactivity to mitogen and no additional effect on T-cell cytotoxicity.


Subject(s)
Bone Marrow Transplantation/immunology , Liver Transplantation/immunology , Bone Marrow Cells/immunology , Cell Division , Cells, Cultured , Graft Rejection , HLA-DR Antigens/immunology , Humans , Immunosuppression Therapy , Lymphocyte Culture Test, Mixed , Lymphocytes/cytology , Lymphocytes/immunology , T-Lymphocytes, Cytotoxic/immunology , Transplantation, Homologous/immunology
13.
J Neurol Neurosurg Psychiatry ; 65(1): 115-8, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9667572

ABSTRACT

Thirty two poor grade patients (grade 3, 20 patients and grade 4, 12 patients) with tuberculous meningitis and hydrocephalus were prospectively studied to evaluate the response to external ventricular drainage in predicting outcome after shunt surgery. All grade 3 patients underwent a shunt procedure irrespective of their response to external ventricular drainage, and an attempt was made to correlate the immediate response to external ventricular drainage to their long term outcome. Patients in grade 4 underwent shunt surgery only if there was clinical improvement by at least one grade after external ventricular drainage. Follow up (mean 23.1 months) was available for 30 patients (93%). Of the 20 patients in grade 3, seven underwent shunt surgery directly, 13 after an external ventricular drainage. In the group which underwent drainage, the immediate clinical response was improvement in six, no change in six, and death in one. Long term improvement or death occurred almost equally in all the subgroups. The immediate response to external ventricular drainage was not predictive of the long term outcome in grade 3 patients. All 12 patients in grade 4 underwent an external ventricular drainage and only one improved. The rest continued to deteriorate and succumbed to the disease. Grade at admission was the single most important predictor of good outcome (p=0.002) and severity of hydrocephalus had an adverse impact on outcome (p=0.04). The rest of the variables studied (age, duration of illness, duration of altered sensorium, CSF cell count, and CSF protein concentrations) had no effect on long term outcome. All patients in grade 3 should be given the benefit of shunt surgery without a trial of external ventricular drainage. However, patients in grade 4 should undergo an external ventricular drainage in view of the high mortality in this group.


Subject(s)
Hydrocephalus/surgery , Tuberculosis, Meningeal/surgery , Ventriculoperitoneal Shunt , Adolescent , Adult , Child , Child, Preschool , Drainage , Female , Follow-Up Studies , Humans , Hydrocephalus/mortality , Infant , Male , Neurologic Examination , Prospective Studies , Survival Rate , Tuberculosis, Meningeal/mortality
15.
Transplantation ; 65(7): 947-55, 1998 Apr 15.
Article in English | MEDLINE | ID: mdl-9565100

ABSTRACT

BACKGROUND: The cascade of immunological effects brought about by donor bone marrow cell (DBMC) infusions in human organ transplantation, especially in the context of continuous pharmacologic immunosuppression, is not fully understood. Yet, in inbred rodents and even primates, administration of specific bone marrow cells has caused a state of acquired immunologic tolerance. METHODS: In vitro mixed lymphocyte culture (MLC) and cell-mediated lympholysis (CML) culture systems were used to compare the responding and regulatory properties of DBMC and individual bone marrow cell subsets versus spleen cells in the presence or absence of pharmacologic immunosuppression. RESULTS: In the absence of immunosuppressive drugs, the DBMC proliferated in MLC and in response to phytohemagglutinin, but to a lower magnitude than donor spleen cells. In CML assays, DBMC failed to function as cytotoxic cells. Removal of both CD3+ and CD34+ cells together (not just singly) had to occur for complete abrogation of the proliferative response of DBMC evoked in the presence of allogeneic stimulating cells. Testing several experimental variables using flow cytometric analysis led to the conclusion that when purified DBMC CD34+ cells were placed in coculture with irradiated allogeneic peripheral blood mononuclear cells, such CD34+ cells give rise both to CD3- TCRalphabeta+ as well as to dimly staining CD3+ TCRalphabeta+ cells. Low pharmacologic concentrations of tacrolimus/cyclosporine (CsA) and mycophenolic acid (MPA) singly or in combination had no effect on the spontaneous proliferation of DBMC and had significantly less inhibitory activity on MLC responses of DBMC and its purified CD3+ or CD34+ subpopulations, compared with the responses of spleen cells. Moreover, the previously described regulatory effects of DBMC on the MLC responses of peripheral blood or splenic responding cells were not inhibited by these immunosuppressive drugs. CONCLUSIONS: Taken together, these results support the notion that in vitro DBMC subpopulations, which proliferate as responding cells in co-culture with x-irradiated allogeneic cells and which cause regulatory effects when added as a third component to MLC reactions, seem to be culture-generated lymphoid cell lineage(s) progeny of CD34+ cells. This possibly includes unique CD3+ "primitive" (dimly staining) T cells, which are not as inhibited in their function by tacrolimus/CsA and MPA, as are postthymic (splenic) T cells.


Subject(s)
Bone Marrow Cells/drug effects , Bone Marrow Cells/immunology , Bone Marrow Transplantation/immunology , Immunosuppressive Agents/pharmacology , Antigens, CD34/immunology , Cadaver , Cell Differentiation/physiology , Cell Division/physiology , Humans , Immunity, Cellular/drug effects , Immunity, Cellular/immunology , Lymphocyte Activation/drug effects , Lymphocyte Activation/immunology , T-Lymphocytes/immunology , Tissue Donors
16.
Br J Neurosurg ; 12(5): 448-51, 1998 Oct.
Article in English | MEDLINE | ID: mdl-10070451

ABSTRACT

Focal amyloidosis (amyloidoma) involving the vertebral spine without an underlying systemic disorder is rare. Only six cases been reported in the literature so far, one involving the cervical spine, the rest occurring in the thoracic region. We present a patient with amyloidoma involving the thoracic spine and describe the magnetic resonance imaging features of this condition.


Subject(s)
Amyloidosis/diagnosis , Magnetic Resonance Imaging/methods , Spinal Diseases/diagnosis , Biopsy, Needle/methods , Humans , Male , Middle Aged , Radiography, Interventional , Thoracic Vertebrae , Tomography, X-Ray Computed
17.
Transplantation ; 63(5): 686-92, 1997 Mar 15.
Article in English | MEDLINE | ID: mdl-9075839

ABSTRACT

BACKGROUND: In order to evaluate whether immunoregulatory mechanisms are brought about by human donor bone marrow cell infusions accompanying organ transplantation, we established in vitro culture systems analogous to the transplant model. METHODS: Cell-mediated lympholysis (CML) and mixed lymphocyte culture (MLC) responses of peripheral blood lymphocytes or spleen cells stimulated with irradiated cadaver donor spleen cells in the presence of specific donor vertebral-body bone marrow cell (DBMC) modulators were tested. RESULTS: When compared with spleen cells as modulator controls, DBMC inhibited both the proliferative and cytotoxic responses in a dose-dependent manner. Use of unirradiated and T cell-depleted DBMC was required for detection of the inhibitory activity. Furthermore, DBMC had to be added within the first 2 days after the initiation of the cultures for the down-regulation of CML (MLC) to occur. The down-regulation of MLC responses could not be shown to be antigen (donor) specific. Physical separation of DBMC from the responder-stimulator cells using the transwell system abrogated modulation of the CML (and MLC) reactions, suggesting the requirement of cell-cell contact for modulatory effect. The inhibitory activity by DBMC could not be overcome by addition of up to 200 U/ml of exogenous recombinant interleukin 2 to the cultures. However, it could be abrogated by restimulation with donor spleen cells, indicating that donor reactive cells were not deleted by DBMC in short-term cultures. CONCLUSIONS: These results showed a regulatory role for DBMC in cellular immune responses against donor cell alloantigens, supporting the rationale for DBMC for facilitating clinical allograft acceptance.


Subject(s)
Bone Marrow Transplantation/immunology , Bone Marrow/immunology , Bone Marrow Cells , Cell Adhesion , Down-Regulation , Humans , Immunity, Cellular , Kinetics
18.
Neurol India ; 45(1): 31-33, 1997.
Article in English | MEDLINE | ID: mdl-29509157

ABSTRACT

Primary leptomeningeal melanoma presenting as a lesion in the region of the pineal gland is rare. The MRI characteristic of this interesting condition is described and its value in studying spread or other foci is emphasized.

19.
Neurol India ; 45(1): 46-47, 1997.
Article in English | MEDLINE | ID: mdl-29509163
20.
Neuroradiology ; 38(5): 468-9, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8837096

ABSTRACT

Retained surgical sponge is an uncommon complication in neurosurgical practice. We report two patients with retained surgical gauze and describe the clinical presentation and the characteristics of the foreign body on MRI.


Subject(s)
Foreign Bodies/diagnosis , Magnetic Resonance Imaging , Surgical Sponges , Adult , Central Nervous System , Female , Humans , Male , Neck/diagnostic imaging , Radiography, Thoracic
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