Differential recognition of murine tumor-associated oncofetal transplantation antigen and individually specific tumor transplantation antigens by syngeneic cloned BALB/c and RFM mouse T cells.

We have previously demonstrated in several species that sarcomas, lymphomas, and carcinomas express a common Ag that cross-reacts with midgestation fetal cells. We also produced a mAb to that protein and characterized it as a 44-kDa glycoprotein. The cross-reactive immunity induced by immunization with tumor or fetal cells expressing the oncofetal Ag (OFA) can be adoptively transferred with cell populations containing T lymphocytes. The experiments discussed within this paper describe the establishment and characterization of two types of T lymphocytes induced by immunization with syngeneic tumor cells in two mouse strains. We find that five of the eight cloned T cells derived from spleens of BALB/c mice that had been immunized with MCA1315 fibrosarcoma cells are specific for an Ag shared by MCA1315 and MCA1321 cells. The other three clones are specific for an Ag present on MCA1315 but not on MCA1321. Also, none of the clones were reactive with the BALB/c plasmacytoma MOPC-315, which does not express OFA. We also find that 75% of the RFM T cell clones from spleens of RFM mice immune to the RFM thymoma 5T show a 5T-specific proliferative response. One of the four clones, however, responds to both 4T and 5T RFM thymoma cells. The BALB/c and RFM cross-reactive clones specifically respond to purified 44-kDa OFA derived from MCA1315 fibrosarcoma cells in the presence of syngeneic irradiated spleen cells and IL-2. All of the clones from both strains of mice, be they tumor-specific transplantation Ag specific or OFA specific, are CD4+, CD3+, alpha beta TCR+ T cells that secrete IFN-gamma on Ag stimulation.

44-kd oncofetal transplantation antigen in rodent and human fetal cells. Implications of recrudescence in human and rodent cancers.

OBJECTIVE: This article summarizes the phase-specific nature of a cell surface, 44-kd tumor-associated transplantation antigen glycoprotein expressed during early and middle gestation in a portion of rodent and human fetal cells during normal fetal tissue development and illustrates how this glycoprotein is consistently recrudesced in primary and established human squamous cell carcinomas and other human and rodent tumors. The oncofetal antigen was not detectable in any human or rodent term fetal tissue or normal adult tissues tested. The tumor-associated transplantation antigen was tumor specific, yet not germ-line specific (expressed in lymphomas, sarcomas, and carcinomas) in human or rodent cancers. Rodent model tumor studies have shown 44-kd oncofetal antigen can act as a tumor-associated autoantigen of potential use in cancer detection and therapy. DESIGN: The oncofetal antigen was detected by immunogenicity, flow cytometry, and Western blotting in syngeneic rodent tumor recipients and by the last two methods in humans with progressive cancer. Syngeneically derived mouse monoclonal antibody (MoAb 115) was used to identify 44-kd oncofetal antigen. Early to middle gestation, oncofetal antigen-positive, mouse embryo/fetal cells used to stimulate the hybridoma were tested for immunogenicity as a tumor-associated transplantation antigen in syngeneic hosts. SETTING AND PATIENTS: Patients presenting with head and neck squamous cell carcinoma (N = 25) and other carcinomas at the University of South Alabama Medical Center, Mobile, underwent a biopsy, and the tumors were mechanically dispersed and were then tested for oncofetal antigen expression directly in flow cytometry. The tumors were also cultured and tested as squamous carcinoma cell lines. Growing squamous carcinoma cells and uncultured tumor cells were stained with MoAb 115 or control MoAb. Extracts of the cells were banded by electrophoresis in gels, Western blotted, and reacted with MoAbs and enzyme-linked immunosorbent assay second antibody. Time-mated mouse fetus and human fetal cells were also stained with MoAb 115 or control antibody and analyzed in the flow cytometer. RESULTS: Eight- to 13-day mouse fetal cells conferred protection against syngeneic tumor challenge. Term 18- to 21-day fetal or neonate or adult mouse cells were nonprotective. All head and neck squamous cell carcinomas tested expressed 44-kd oncofetal antigen by flow cytometric analysis and in Western blots as did ATCC cell lines of these tumors, whereas normal control tissues were negative. Second trimester human fetal cells were 44-kd oncofetal antigen positive. A large spectrum of rodent sarcomas and lymphomas express the OFA. CONCLUSIONS: Shared 44-kd oncofetal antigen OFA offers promise as a tumor detection marker in human squamous cell carcinoma and other human carcinoma development, and syngeneic mouse tumors are good model systems to explore oncofetal antigen antigenicity.

Expression of 44-kilodalton oncofetal antigen as a premalignancy marker in X irradiation-induced murine T-cell lymphoma.

BACKGROUND: Oncofetal antigens (OFAs) are found on the surface of murine and human midgestation fetal cells, in human and rodent tumor tissues, and on human and rodent tumor and embryonic cell lines but not in normal neonatal or adult human and rodent tissue. PURPOSE: The usefulness of OFA as an early indicator of lymphoma development was evaluated. METHODS: With the use of monoclonal antibody directed against a 44-kd glycoprotein, cells from the thymus and spleen of RFM/UnCr mice receiving whole-body, split-dose x irradiation (1.75 Gy once a week for 4 weeks) or cells from these organs from control (nonirradiated) mice were analyzed for the presence of OFA in the flow cytometer and in limited intrathymic transplant. RESULTS: OFA was detected on thymocytes from 75% of irradiated mice by 2 months after treatment, reflecting eventual lymphoma development in the irradiated controls by flow cytometry and in intrathymic transplant. In general, the number of thymuses expressing OFA and the percentage of OFA+ cells increased with time after irradiation. By 4 months, OFA+ splenocytes were present, but only in mice possessing OFA+ thymocytes. Serially tested, irradiated RFM mice that never expressed OFA in the thymus reflected the percentage of irradiated RFM/UnCr mice that never developed lymphomas. This observation was also made in irradiated C57BL/6N mice, which attests to the tumor specificity of OFA expression. Spleen immunoglobulin-positive cells were decreased, while CD4+ and CD8+ cells were greatly increased. Indirect evidence of CD4/CD8 expression on OFA+ splenocytes suggests that the newly forming lymphomas were of immature T-cell origin. Major histocompatibility antigen expression did not vary significantly. Histopathologic examination revealed radiation-induced lymphomas in OFA-positive tissues characterized by a monomorphic population of large blastic immature lymphoid cells. CONCLUSION: The early expression of OFA in radiation-induced oncogenesis was established. IMPLICATIONS: OFA expression significantly preceded clear histologic evidence of malignant T cells or clinical lymphoma in irradiated RFM/UnCr mice that went on to develop T-cell lymphomas.

Differential expression of class I major histocompatibility complex determinants by lymphoblastic leukemia-lymphoma cell lines.

Two T-cell lines (XR11-4T and XR11-5T), established from radiation-induced, murine lymphoblastic lymphomas, were examined for the expression of class I major histocompatibility complex antigen and tumor induction. These cell lines expressed class I private determinants, H-2.9 and H-2.26, but not the monomorphic determinant defined by monoclonal antibody M1/42. Both cell lines produced tumors in syngeneic and allogeneic hosts. The monomorphic determinant could be demonstrated on both cell lines following growth in allogeneic (BALB/c mice) but not in syngeneic (RFM mice) hosts. The re-expressed determinant present on cells following growth in allogeneic mice was not of host origin. Thus, tumorigenic x irradiation may differentially affect the expression of class I major histocompatibility complex determinants.

Human squamous cell carcinoma lines express oncofetal 44-kD polypeptide defined by monoclonal antibody to mouse fetus.

Most primary human carcinomas uniformly express an oncofetal epitope which has not been demonstrated previously in established human carcinoma cell lines. We successfully derived several low-passage cell lines of human squamous cell carcinoma (SCC) from head and neck tumors using an in vitro adaptation procedure, characterized these lines, and examined them for expression of a 44-kilodalton (kD) polypeptide (PP) oncofetal antigen (OFA) at the cell surface. Newly established an in vitro-passaged SCC cells retained characteristic microvilli, numerous desmosomes and tonofilaments, abundant rough endoplasmic reticulum, osmophilic keratohyaline granules, and other features of the primary SCC cells. These new cell lines and two long-term, established SCC lines (FaDu and Detroit 562) displayed OFA at the cell surface, as determined by flow cytometry using monoclonal antibody (MoAb) 115. While the FaDu and Detroit 562 lines exhibited aneuploidy during flow cytometric analysis, the new, low-passage SCC lines that we developed remained diploid as were the primary SCC cells from which they were derived. We propose that the expression of a 44-kD OFA is a common feature of human SCC. This marker may prove useful in the detection and treatment of these tumors.

Radiation-induced lymphoblastic lymphomas/leukemias and sarcomas of mice express conserved, immunogenic 44-kilodalton oncofetal antigen.

X-ray-induced, lymphoblastic, T-cell lymphoma/leukemias from irradiated RF mice were observed to uniformly expressed a 44-kd oncofetal antigen (OFA). The OFA polypeptide was detected by flow cytometry, affinity column SDS-PAGE analysis, and immunoblotting with monoclonal antibody (MAb) 115 prepared against syngeneic mouse fetus. X-ray and ultraviolet (UV) induced murine fibrosarcoma cell lines, used as classic models in radiation biology, were also found to express the OFA, which suggested that the 44-kd OFA was a general transformation marker of tumors. Adult mouse thymocytes and other adult tissues expressed no OFA. The 44-kd polypeptide was located at the surface membrane of the tumors examined. In contrast to other reports, lymphoblastic lymphoma cell lines expressed the OFA as a cross-protective, rather than an individually-specific, tumor-associated transplantation antigen. Pronase treatment removed OFA from the surface of living lymphoma cells, whereas collagenase, neuraminidase, and hyaluronidase did not. The OFA was rapidly reexpressed upon culture of the pronase-treated cells. Taken together, these results suggest that the 44-kd OFA polypeptide described here may provide a useful cell surface marker for future radiation carcinogenesis studies. MAb 115 is a promising reagent for detecting tumor-associated 44-kd OFA, for assessing immunoregulatory perturbations to the OFA caused by radiation damage and for investigating the immunopathology of OFA-associated radiation damage.

Lymphocyte kinetics in acute uremia: redistribution of circulating lymphocytes to the bone marrow.

The mechanism(s) responsible for the peripheral blood lymphocytopenia found in uremia was investigated. Inbred Magnum guinea pigs were made uremic by ureteral ligation, and 1 day later injected with chromium (Cr)51-labeled syngeneic lymphocytes intravenously. 1 day later, the animals were sacrificed and organs counted for radioactivity. Sham-operated animals served as controls. Radioactivity in the lung and liver was the same or greater in the sham-operated animals than in uremic animals. In the blood and spleen, radioactivity was slightly higher in the uremic animals, while in the long bones this was significantly higher. In uremia therefore, there appears to be a redistribution of circulating lymphocytes to the bone marrow. The resultant lymphocytopenia may play a role in the immunologic incompetence seen in uremia.