geiercr2.jpg (105383 bytes) Dr Steve Geier - Ph.D. Duke University

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Dr Geier is a member of the Department of Microbiology and Immunology. He works at the Center for Cancer Treatment and Research at Richland Memorial Hospital. This hospital is the major teaching hospital associated with the Medical School

Bone marrow and solid organ transplantation are increasingly successful due to advances in many areas. These include HLA matching, immunosuppression to minimize rejection, growth factors, surgical techniques, and organ procurement, preservation, and processing. A better understanding of the immunobiology of transplants is needed to design more specific and effective procedures. The characterization and control of cells, factors, receptors and determinants in graft rejection, involves both basic and clinically applied research. Bone marrow transplantation is being used to replace damaged or defective stem cells, introduce genes, and to increase the effectiveness of cancer treatments by allowing high dose therapies, which destroy more cancer cells, but also stem cells. My research is on: improving HLA matching and immune function post transplant and the characterization and control of immune cells in donor marrow: The selective removal of anti-recipient immune cells in donor marrow, to minimize rejection of the recipient, but leave cells which can help protect against infections. The characterization and expansion of protective immune cells to destroy residual cancer cells or pathogens. The introduction of genes which provide control of donor immune cells.

PUBLICATION

Geier SS, Zeff RA, McGoven DM, Rajan TV, Nathenson SG: An Approach to the study of structure-function relationships of MHC class I molecules: Isolation and serologic characterization of H-2Kb Somatic cell variants. J Immunol 137:1239, 1986.

Summary

Somatic cell variants expressing an altered antigenic form of the H-2Kb

molecule were isolated for the purpose of performing structure-function analysis of a Class I MHC molecule. Over 25 independently isolated variants were derived from an Abelson virus transformed pre B-cell line (R8) by mutagenesis with ethyl methane sulfonate (EMS) or ethyl nitrosourea (ENU). Negative selection was performed by complement-dependent cyto-toxicity with anti-H-2Kb monoclonal antibodies subsequently followed by positive selection to separate the H-2Kb surface negative variants from structural variants. Biochemical characterization of a random selection of e independent variants indicated that the variant H-2K2 molecule was present in normal amounts in lysates, and unchanged in size. Cytofluorometric analysis using a panel of seven monoclonal antibodies against h-2Kb indicated that all the variants had lost one or more alloantigenic determinants (monoclonal antibody binding sites). For these variants, the pattern o f monoclonal antibody loss of recognition suggested that antibody defined alloantigenic determinants appear to be discretely localized to a single domain, either the or 2 domain, for the H-2Kb molecule. In contrast, CRL recognition of the Kb molecule of these variants depends on involvement of both 1 and 2 domains.

PUBLICATION

Ajitkumar P., Geier S.S., Kesari K.V., Borriello F., Nakagaw M., Bluestone J.A., Saper M.A., Wiley D.C., Nathenson S.G. Evidence the multiple residues on both the a-Helices of the class I MHC molecule are simultaneously recognized by the T cell receptor. Cell 54:47-56, 1988.

Summary

Single amino acid substitutions at nine different positions on the H-2Kb molecules from in vitro mutagenized, immunologically altered, somatic cell variants were correlated with their patterns of recognition by monoclonal antibodies (MAbs) and allogeneic cytotoxic T lymphocyte (CTL) clones. While MAbs were found to detect spatially discrete, domain-specific sites, CTLs interacted simultaneously with multiple residues on the 1 and 2 domains of the Kb molecule. The computer graphic three-dimensional Kb model structure showed that, of the seven CTL-specific residues analyzed, six residues were located on the -helical regions of the two domains. Every CTL clone was found to interact with a distinct pattern of residues composed of a specific subset of the CTL-specific residues.

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Coffman T., Geier S.S., Ibrahim S., Griffiths R., Spurney, Smithies O., Koller B.H., Sanfilippo F. Improved renal function in mouse kidney allografts lacking MHC class I antigens. J Immunol 151:425-435, 1993.

Summary

The immunological responses that lead to rejection of organ and tissue transplants are triggered by the recognition of proteins encoded within the MHC. The relative contributions of responses directed toward MHC class I compared with class II in the loss of functional integrity of vascularized organ grafts have been difficult to define. The recent development of technologies which allow the generation of mice in which specific genes have been altered by gene targeting offers a new approach to addressing this question. We examined the rejection of kidney allografts from mice lacking native MHC class 1 Ag. These mice were obtained from embryonic stem cells in which the 2 microglobulin (2m) gene had been disrupted by homologous recombination. We found a significant improvement in function of renal allografts MHC class I-deficient donors compared with allografts donors with normal MHC class I expression. Surprisingly, the improved function of the MHC class I deficient grafts was not associated with differences in mononuclear inflammatory cell infiltration of these grafts nor in differences in alloreactive proliferative or cytotoxic T cell responses. However, we did find differences in alloantibody response between the groups. Recipients of control allografts produced antibodies against both donor MHC class In and II, whereas recipients of MHC class I-deficient grafts formed alloantibodies primarily against donor MHC class II Ag. These studies confirm that immune responses directed toward donor MHC class I alloantigens contribute to kidney transplant dysfunction in this model. Also, these findings suggest that, at least for renal transplant, genetic manipulations which reduce MHC class I expression may be effective in overcoming some of the effects of MHC incompatibility.

PUBLICATION

Lamb, L.S., Gee, A.P., Parrish, R.S., Lee, C., Walker, M., Geier, S., Harris, G., Pati, A., Godder, K., Henslee-Downey, P.J. Acute rejection of marrow grafts in patients transplanted from a partially mismatched related donor: clinical and immunologic characteristics. Bone Marrow Transplant. 17:1031-1027, 1996.

Summary

Bone marrow transplantation (BMT) from a partially mismatched related donor (PMRD) provides a treatment option for patients lacking a matched sibling donor. T lymphocyte depletion of the graft reduces the risk of severe graft-versus-host disease, but may increase the risk of graft failure. We evaluated the pattern of acute graft rejection in eight patients receiving PMRD BMT with respect to the conditioning therapy, diagnosis, age, and sex of donor and recipient, degree of HLA mismatch, and peripheral blood immunopheno-type at the time of graft failure. All grafts were partially depleted of T lymphocytes. Marrow grafts infused into patients who experienced acute rejections did not differ significantly in nucleated cell dose, degree of lymphocyte depletion, T cell dose, or CFU-GM/kg infused, from those received by 31 patients who showed durable engraftment. In three of four patients who rejected their grafts, and had sufficient peripheral blood cells for immunophenotyping, a CD3+CD+ T lymphocyte phenotype was predominant at the time of acute rejection. In one patient rejection was associated with a predominant population of CD3+CD4+ T lymphocytes. Rejection was significantly associated with chronic myelogeneous leukemia and in patients mismatched by more than two antigens.

PUBLICATION

Geier SJ, Algate PA, Carlberg K, Flowers D, Friedman C, Trask B, Rohrschneider LR The human SHIP gene is differentially expressed in cell lineages of the bone marrow and blood. Blood 1997 Mar 15;89(6):1876-85

The macrophage colony-stimulating factor receptor and several other hematopoietic growth factor receptors induce the tyrosine phosphorylation of a 145- to 150-kD protein in murine cells. We have previously cloned a cDNA for the murine 150-kD protein, SHIP, and found that it encodes a unique signaling intermediate that binds the SHC PTB domain through at least one tyrosine phosphorylated (NPXY) site in the carboxyl-terminal region. SHIP also contains several potential SH3 domain-binding sites, an SH2 domain for binding other tyrosine phosphorylated proteins, and an enzymatic activity that removes the phosphate from the 5 position of phosphatidylinositol 3,4,5-phosphate or from inositol 1,3,4,5-phosphate. SHIP has a negative effect on cell growth and therefore loss or modification may have profound effects on hematopoietic cell development. In this study, we have cloned a cDNA for human SHIP and examined mRNA and protein expression of SHIP and related species in bone marrow and blood cells. Flow cytometry indicates that at least 74% of immature CD34+ cells express SHIP cross-reacting protein species, whereas within the more mature population of CD33+ cells, only 10% of cells have similar expression. The majority of T cells react positively with the anti-SHIP antibodies, but significantly fewer B cells are positive. Immunoblotting detects up to seven different cross-reacting SHIP species, with peripheral blood mononuclear cells exhibiting primarily a 100-kD protein and a CD34+ acute myeloblastic leukemia expressing mainly 130-kD and 145-kD forms of SHIP. Overall, these results indicate that there is an enormous diversity in the size of SHIP or SHIP-related mRNA and protein species. Furthermore, the expression of these protein species changes according to both the developmental stage and differentiated lineage of the mature blood cell.

PUBLICATION

Henslee-Downey PJ, Abhyankar SH, Parrish RS, Pati AR, Godder KT, Neglia WJ, Goon-Johnson KS, Geier SS, Lee CG, Gee AP Use of partially mismatched related donors extends access to allogeneic marrow transplant. Blood 1997 May 15;89(10):3864-72

Most patients requiring allogeneic bone marrow transplant (allo-BMT) do not have an HLA-matched sibling donor. A phenotypically matched unrelated donor graft has been made available for approximately 50% of Caucasians and less than 10% of ethnic and racial minorities in need. However, almost all patients have a readily
available partially mismatched related donor (PMRD). We summarize our experience with 72 patients who ranged from 1 to 50 years of age (median, 16 years) and
who were recipients of a PMRD allo-BMT from haploidentical family members following conditioning therapy using total body irradiation (TBI) and multiagent,
high-dose chemotherapy. T-cell depletion and post-BMT immunosuppression were combined for graft-versus-host disease (GVHD) prophylaxis. The probability of
engraftment was 0.88 at 32 days. Six of 10 patients who failed to engraft achieved engraftment after secondary transplant. Grade II to IV acute GVHD was seen in 9 of 58 (16%) evaluable patients; extensive chronic GVHD was seen in 4 of 48 (8%) evaluable patients. There was a statistically significant difference in 2-year survival probability between low-risk and high-risk patients (0.55 v 0.27, P = .048). Prognostic factors that affected outcomes in multivariate analysis were (1) a lower TBI dose and 3-antigen rejection mismatch decreased stable engraftment (P = .005 and P = .002, respectively); (2) a higher T-cell dose increased acute GVHD (P = .058); (3) a higher TBI dose increased chronic GVHD (P = .016); and (4) a high-risk disease category increased treatment failure from relapse or death (P = .037). A PMRD transplant can be performed with acceptable rates of graft failure and GVHD. Using sequential immunomodulation, the disease status at the time of transplant is the only prognostic factor significantly associated with long-term successful outcome after PMRD allo-BMT. When allogeneic rather than autologous BMT is indicated, progression in disease status before transplant can be avoided using a PMRD with equal inclusion of all ethnic or racial groups.

 

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Godder KT, Abhyankar SH, Lamb LS, Best RG, Geier SS, Pati AR, Gee AP, Henslee-Downey PJ Donor leukocyte infusion for treatment of graft rejection post partially mismatched related donor bone marrow transplant. Bone Marrow Transplant 1998 Jul;22(1):111-3


Graft rejection following bone marrow transplantation is more common in patients who receive their grafts from alternative donors and whose marrow is T cell depleted. Rejection in these patients is mediated by persistent host cells that interfere with successful establishment of donor-derived hematopoietic recovery. We describe a patient with chronic myelogenous leukemia in accelerated phase who rejected a T cell-depleted bone marrow graft, 2 months following partially mismatched related donor bone marrow transplant. Unmanipulated peripheral blood donor leukocyte infusion, without additional chemotherapy or immunosuppressive therapy resulted in complete hematopoietic recovery. Cytogenetics and RFLP demonstrated hematopoietic donor chimerism. The patient did not develop graft-versus-host disease.


PUBLICATION

Lamb LS Jr, Gee AP, Henslee-Downey PJ, Geier SS, Hazlett L, Pati AR, Godder K, Abhyankar SA, Turner MW, Lee C, Harris WG, Parrish RS Phenotypic and functional reconstitution of peripheral blood lymphocytes following T cell-depleted bone marrow transplantation from partially mismatched related donors. Bone Marrow Transplant 1998 Mar;21(5):461-71

Myeloablative chemotherapy followed by transplantation of a T cell-depleted bone marrow graft from a partially mismatched related donor provides a potentially curative option for patients with leukemia and other disorders of hematopoiesis, although the patient is faced with a period of sustained immunodeficiency as well as pharmacologic immunosuppression as a result of prophylaxis against graft-versus-host disease. Thirty patients who received one to three antigen T cell-depleted mismatched grafts were evaluated for immune reconstitution. The percentage and numbers of cells expressing lymphocyte subset antigens were determined by flow cytometry at 14, 28, 60, 100, 180, 270 and 365 days post-BMT and at 6 month intervals thereafter. Lymphocyte reconstitution was characterized by the early appearance of natural killer cells and a low percentage of both T and B cells. During the first year after BMT, the number of NK cells remained constant while T and B cells gradually returned to normal numbers and proportions. Response to the lymphocyte mitogen phytohemagglutinin returned to normal over the course of 2 years, while the response to concanavalin A was slightly depressed and the response to pokeweed mitogen became supranormal at about 1.5 years and continued to increase. These data suggest the need for long-term immunophenotypic monitoring as well as prolonged infection surveillance and prophylaxis.

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