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Tumor stem cells or cancer initiating cells are tumor cells that can regenerate a recurring tumor or a metastasis. A variety of cell surface and other markers have been associated with identification and characterization of tumor stem cells. We investigated the expression of a number of these putative stem cell markers (CD15, CD24, CD44, CD133, CD166, CD326, PgP, and aldehyde dehydrogenase) in the NCI60 tumor panel. A spectrally compatible set of labeled antibodies was designed to enable simultaneous evaluation of six markers (CD44, CD24, CD133, CD166, CD326 (EpCAM), and PgP, and forward (FSC) and side scatter (SSC). Marker expression patterns were analyzed by multiple component analysis and correlated with clonogeneic potential of cell lines (2D colony formation assay, anchorage independent colony formation in soft agar assay). Additionally sphere formation in suspension culture and the capacity of cell lines to form tumors in vivo upon injection with matrigel was assessed for colon cancer cell lines. Analysis of expression of single markers and co-expression of up to 6 markers demonstrated that all stem cell markers investigated are expressed in cell lines of the NCI-60 panel. Patterns of co-expression of these markers as defined by multiple component analysis tracked primarily with tumor type, but individual patterns were also observed to occur in multiple tumor types. In the breast cancer panel the patterns of co-expression segregated with the known molecular sub-types (basal, luminal, normal-like) of the tumor cell lines. Cells from colonosphere cultures generated from the colon tumor panel using serum-free, growth factor supplemented medium showed subtly different co-expression patterns. Both sphere-derived and bulk cultured colon tumor cells were highly tumorigenic in NOD/SCID mice and tumor formation was observed following inoculation of 10-100 cells. Only two out of seven of the colonosphere derived cell populations had enhanced tumor initiating ability, but did not share differences in stem cell marker display with respect to the unselected bulk cultures. Furthermore, marker expression patterns did not significantly correlate with in vitro colony formation (2D culture, soft agar). Our results demonstrate a high degree of complexity and heterogeneity in tumor stem cell marker display that can be influenced by culture conditions and relates to the histological classification of tumors rather than to the clonogenic potential of cells in cell lines of the NCI60 panel. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3372.

Cancer growth and metastasis involve an active interaction between primary tumor cells and the tumor's microenvironment, which consists of fibroblasts, vascular cells and inflammatory cells. Such interactions between the cancer and the cells within the microenvironment induce differential expression of genes that act to foster the growth, invasion and spread of tumor cells. This study utilizes pair-wise primary cultures of fibroblasts from normal and cancerous human endometrial tissues of the same patients to investigate the potential factors in the tumor microenvironment and their role in carcinogenesis. Both microRNA and mRNA profiling were performed on paired normal and cancer fibroblasts. SatB2 emerged as a promising candidate when its expression was shown to be significantly increased in fibroblasts surrounding the tumor tissues in all but one patients tested (n=8). Further investigation documented that SatB2 is a target for miR31, via 2 binding sites located within the SATB2 3’ UTR region. In concordance, miR31 is down-regulated in tumor fibroblasts, which further implicates the potential role of SatB2 in promoting a favorable environment for tumors. Ectopic expression of SATB2 in normal fibroblasts does not affect the growth rate of an endometrial cancer cell line (EC-1) in co-culture experiments; however, it did increase the motility of EC-1 cells towards these fibroblasts by multiple folds in both in vitro migration and invasion assays. A reduction of SATB2 expression in cancer activated fibroblasts (CAFs) by shRNA attenuated the migratory ability of EC-1 cells, further supporting the role of SatB2 in tumor aggression. Our observations also indicated that the conditioned media from CAFs were sufficient to induce the motility changes in the EC-1 cells. We believe the elucidation of SatB2 pathway(s) will assist in uncovering the intricate connections between tumors and their microenvironments, leading to new targets for treating tumor progression. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1423.

• In recent years, the morbidity, mortality, and long-term survival of patients undergoing surgery for periampullary adenocarcinoma have improved. These changes have prompted us to reoperate on patients who have previously undergone pancreatobiliary surgery, many of whom were initially considered to have unresectable lesions. From 1979 to 1990, 38 patients with pancreatic and 17 patients with nonpancreatic periampullary adenocarcinoma underwent reexploratory surgery at The Johns Hopkins Hospital, Baltimore, Md. Thirty-three (60%) of these 55 patients had resection at the time of second laparotomy. Of the 46 patients undergoing reexploratory surgery with an intent to resect, the overall resection rate was 72% (33), 64% (16/25) for pancreatic and 100% for nonpancreatic periampullary adenocarcinoma. Postoperative complications occurred in 21 patients (38%), but only one patient (2%) died following surgery. Mean survivals from reexploratory surgery were 6.9 months for the 22 patients with pancreatic cancer undergoing palliative surgery, 20.5 months for the 16 patients with resectable pancreatic cancer, and 33.0 months for the 17 patients with nonpancreatic periampullary adenocarcinoma undergoing resection. We conclude that in carefully selected patients, reoperative surgery for periampullary cancer (1) provides a significant resection rate, (2) can be performed safely, and (3) offers a chance for long-term survival. ( Arch Surg. 1991;126:1205-1212)

We have demonstrated in an anti-Ia serum the presence of specific antibodies reacting with T cells, as well as with B cells, using a highly sensitive dye exclusion test. This antiserum reacts with both spleen and lymph node in a characteristic biphasic titration curve killing up to 70% of these cells. It also reacts with cortisone-resistant thymocytes. The A.TH-α-A.TL serum can be absorbed with spleen, lymph node, cortisone-resistant thymus, or normal thymus cells. Further in vivo absorptions in BALB/c nude cannot remove all of the cytotoxic activity for normal BALB lymph node lymphocytes, while completely removing the activity for nude cells. A Thy-1 positive cell line derived from a C57Br leukemia is reactive with this anti-Ia serum.

Biodegradable starch microspheres, 40 μm in diameter, were administered through hepatic arterial catheters in 16 subjects with primary and metastatic liver tumors. These microspheres temporarily obstruct blood flow at the precapillary arteriole (microcirculation) level. Our study was undertaken to determine whether such occlusion would enhance hepatic deposition of, and thereby decrease systemic exposure to, simultaneously administered hepatic arterial mitomycin C (mito). When mito (10 mg/m2 over 1 min) was given with 90 × 106 microspheres (10 subjects), there was a 17% to 70% reduction in systemic mito exposure. When mito (10 mg/m2 over 1 min) was given with 36 × 106 microspheres (six subjects), there was a 15% to 60% reduction in systemic exposure, which may correlate with dose-dependent shunting (8% to 29%) through the liver to the lung (and hence to the systemic circulation), attributed to the starch microspheres. No life-threatening myelosuppression was noted; hepatic toxicity consisted of transient pain and elevation of liver enzymes. Clinical Pharmacology and Therapeutics (1983) 34, 259–265; doi:10.1038/clpt.1983.163

Genes mapping in the I region of the H-2 complex control a system of lymphocyte alloantigens (Ia) which are expressed on a subpopulation of T cells and on most B cells. Specific anti-Ia serum in the presence of rabbit complement removed the splenic T-cell subpopulation responsive to Con-A, but did not affect the response to phytohemagglutinin (PHA) or Leucoagglutinin. Antibodies specific for Ia, H-2K, or H-2D membrane antigens were used without complement to pretreat spleen cells. These antibody pretreated cells responded normally to Con-A and PHA.

Five-day continuous intraperitoneal (ip) infusions of 5-fluorouracil (FU) were injected into five patients as part of a phase 1 clinical pharmacology study. They received 20 courses through a totally implanted catheter/injection port system. Six courses are evaluable for kinetic parameters and all courses are evaluable for toxicity. In each course a 2 to 3 log FU concentration differential in favor of the peritoneal cavity was achieved and maintained. Steady-state venous plasma FU concentrations averaged 0.34 µM, whereas steady-state ip FU concentrations averaged 697 µM. Mean total body clearance (TBC) in these patients was 18.4 l/min and mean permeability-area (PA) product for diffusion from the peritoneum was 13.7 ml/min. Mean TBC of 20 l/min with ip FU infusion was observed in one patient who also received a 24-hr IV FU infusion for comparison. The TBC during the later infusion was 5.9 l/min. In this patient, calculations indicate 75% extraction of drug during the passage from the peritoneum to the systemic circulation, presumably representing in large part hepatic extraction of FU taken into the portal venous circulation. Ip constant infusion and bolus kinetics were compared in one patient. TBC for the ip bolus was 14.3 l/min, which was approximately half of the TBC of 29.5 l/min determined during the 5-day constant ip infusion. Thus constant ip infusion of FU (1 gm/day) can provide an improved regional advantage over bolus ip FU because of an increased TBC. Toxicity was acceptable in all courses. Dose limiting toxicity was regional, namely moderate chemical peritonitis seen in two of the five patients on repeated courses. There was no myelosuppression, alopecia, nausea, or vomiting. There were no infectious complications. The only patient with measurable disease had an objective response in hepatic metastases from gastric cancer. The implanted device was well tolerated and facilitated peritoneal fluid sampling. Clinical Pharmacology and Therapeutics (1984) 35, 83–89; doi:10.1038/clpt.1984.12

Allogeneic Con A induced suppressor cells differing in the I and S region but not H -2 K or H -2 D regions were as efficient as syngeneic cells in suppressing the secondary IgM and IgG response to burro erythrocytes. Con A activated suppressor cells were not sensitive to anti-Ia serum and complement. However, if the spleen cell population was treated with anti-Ia serum and complement before stimulation with Con A, suppressor cells were not generated.

Starch microspheres 40 micrometers in diameter, which are rapidly degraded by serum amylase, have been administered through hepatic arterial catheters to five patients with primary and metastatic liver cancer to determine whether (1) arterial blood flow through the liver could be temporarily blocked, and (2) such occlusion at the level of the arteriolar capillary bed would enhance regional uptake and catabolism and decrease systemic exposure to simultaneously administered hepatic arterial bischlorethylnitrosourea (BCNU). It was possible with 10 ml of microspheres (9 X 10(6) microspheres/ml) injected into the hepatic artery to transiently (for 15-30 minutes) reduce hepatic flow by 80-100% in the five patients. When BCNU (50 mg/m2 in one minute) was given with microspheres there was a 30-90% reduction in systemic nitrosourea exposure and in peak levels. No myelosuppression was noted and hepatic toxicity consisted of acute pain due to BCNU and 1.5-2.0 fold transient enzyme elevations. One patient with cholangiocarcinoma showed a partial response lasting three months; three patients had stable disease and one patient with colon carcinoma had progressive disease. Thus, this pilot study suggests that concurrent intra-arterial microspheres and BCNU may have the potential to improve selective regional drug effect with marked diminution in systemic toxicity.

We have shown that the Ia determinants expressed on nylon wool-purified T lymphocytes reactive to concanavalin A (Con A) in serum-free media are coded in a single I subregion of the H-2 gene complex. This region, I-J, is defined by two pairs of intra-H-2 recombinant haplotypes: H-2t3, H-2t4 and H-2i3, H-2i5, carried by B10.HTT, B10.S(9R), B10.A(3R), AND B10.A(5R), respectively. No activity against Con A-reactive T cells has been detected in any antiserum that was produced in strain combinations which shared a common I-J region. This suggests that Ia antigens expressed on Con A-reactive T cells are restricted to the I-J subregion.

The primary in vitro antibody response to TNP-Ficoll was found to be under H-2-restricted Ir gene control. Strains B10(H-2b), B10.A(H-2a), and B10.S(9R) (H-2t4) were consistently low responders while strains D2.GD(H-2g2), B10.GD(H-2g2), and B10.S(H-2s) were high responders. The in vitro TNP-Ficoll response in congenic recombinant and F1 hybrid mice demonstrated the requirement for complementation of two independent Ir genes. One Ir gene mapped in or to the left of the I-A subregion with high responder alleles being s or d. The second Ir gene mapped to the right of the I-E subregion and required b or s alleles for complementation. These results were further supported by the ability to block the TNP-Ficoll response by appropriate anti-Ia serum pretreatment of the antigen-presenting macrophages. When a structurally different polysaccharide antigen TNP-dextran was used, an identical pattern of restriction was observed.

Ninety-three patients with biopsy-proven colorectal cancer metastatic to the liver were treated with hepatic arterial infusion of 5-fluorodeoxyuridine (FUDR). There were 52 men and 41 women (median age, 60 years). Forty-two patients (45%) had failed prior systemic chemotherapy. Catheters were operatively placed and multiple catheters were used if dictated by hepatic arterial anatomy in order to obtain perfusion of the entire liver. The drug was delivered by a totally implanted INFUSAID model 400 pump and patients received cyclic therapy consisting of 2 weeks of 0.3 mg/kg/d FUDR alternating with 2 weeks of saline. Patients with extrahepatic tumor or patients whose hepatic tumor failed to respond to FUDR were given a 30 minute intraarterial infusion of mitomycin C, 15 mg/m2, every 6 to 8 weeks in addition to FUDR. Fifty of the 93 evaluable patients presented with metastatic tumor confined to the liver. Of these 50 patients, 83% demonstrated a significant reduction in tumor size with a median duration of response of 13 months and a median survival of 25 months from diagnosis of liver metastases. Twenty-four of these 50 patients remain alive. Forty-three patients presented with extrahepatic metastases in addition to their liver tumor, and 74% had a response with a median duration of 6 months and a median survival of 14 months. Only six patients of those presenting with extrahepatic tumor remain alive. None of the 93 patients died solely of uncontrolled liver tumor, and only 9 died as a result of uncontrolled liver metastases and disseminated extrahepatic tumor. The duration of survival for both groups was determined by the uncontrolled progression of extrahepatic tumor. In patients with metastatic colorectal cancer involving only the liver, hepatic arterial FUDR alone and with the addition of mitomycin C provided excellent control of hepatic tumor. Survival appeared to be prolonged in this uncontrolled study.

Large numbers of maternal lymphocytes are present in breast milk. We asked whether exposure of an infant to maternal lymphocytes during the process of breast feeding would have an effect on the subsequent reactivity of a patient to a maternal-donor related renal transplant. We studied the posttransplant course of 55 patients who had received a primary maternal-donor transplant. Twenty-seven recipients had been breast-fed during infancy and 28 recipients had not been breast-fed. A history of breast feeding was associated with a more favorable posttransplant course as measured by the percentage of patients who had no rejection episodes during the first posttransplant year (P less than or equal to .006). The one-year graft function rate for breast-fed recipients was 82%; this was statistically significantly better than the 57% measured for non-breast-fed recipients (P less than or equal to .05). Statistical significance of differences between groups was not attained when results were evaluated over a five-year interval. A difference between breast-fed and non-breast-fed recipients was not apparent when we evaluated a somewhat smaller group of patients who had received a paternal donor transplant. From these observations we conclude that the process of breast feeding during infancy may result in a measurable immunologic benefit to the recipient of a subsequent maternal-donor related renal transplant.

Cultures of bone marrow stem cells, grown in the presence of L-cell-conditioned medium, were harvested on successive days to determine the expression of Ia antigens and the acquisition of Ir4 gene-regulated antigen presentation. I-A subregion antigen expression was detected by an indirect radiobinding assay (RBA) as early as day 3 and reached maximal binding at day 7, before declining with additional time in culture. Indirect immunofluorescence (IIF) demonstrated 20% Ia+ cells on day 3 of culture and peaked at 60% on day 7 before declining with continued incubation. A mixed lymphocyte reaction (MLR) across an I region difference was used to assess the kinetics of bone-marrow-derived macrophage ( BMDM ) Ia expression. Maximal stimulation occurred with BMDM stimulator cells obtained from 5-9-day cultures. To investigate the acquisition of Ir gene function, BMDM harvested after various days in culture were used to reconstitute the T cell proliferative response to poly Glu60Ala30Tyr10 (GAT). The ability of BMDM to present GAT was detected after day 5, increased to maximal levels on day 7, and then declined with weak proliferative responses obtained using day 12 BMDM . The presentation of GAT by BMDM was inhibited by monoclonal anti-Ia. 17 antibody. Thus, the acquisition of Ir gene function by BMDM was found to parallel the expression of Ia molecules. Additional experiments were performed to determine whether treatment of BMDM at day 7 with lymphokines or beta-interferon could extend Ia antigen expression. Whereas treatment of day 7 BMDM cultures with Con-A-stimulated rat splenocyte supernatants extended and augmented Ia expression for an additional three days, beta-interferon treatment did not result in augmentation or extension of Ia antigen expression.

A primary leiomyosarcoma of skin was studied by light and electron microscopy and by histochemistry. Systematic evaluation of the entire neoplasm suggested that a single biopsy sample would show little cellular pleomorphism but could vary considerably in number of mitoses per mm2. Electron microscopy revealed a high degree of cytologic differentiation. Strong myosin ATPase activity and negative demonstrations for hydrolytic enzymes suggest a diagnostic profile which will clearly separate this neoplasm from malignant fibrous histiocytoma. High mitoses counts, the conventional criterion for malignancy of non-cutaneous smooth muscle tumors, may not be appropriately applied to primary leiomyosarcomas arising in the dermis. The findings in this case and a critical review of the literature suggest that reliable criteria for diagnosis of primary cutaneous leiomyosarcoma by light microscopy remain to be established.

Antigen-presenting macrophages (M phi) were derived from day 7 cultures of bone marrow stem cells using L cell conditioned medium. The adherent bone marrow-derived macrophages (BMM phi) were 100% esterase-positive, 95% positive for C3 receptors, 93% positive for Fc receptors, and 95% actively phagocytic. Indirect immunofluorescence using anti-Ia monoclonal antibodies resulted in 60% Ia-positive BMM phi on day 7 of stem cell culture. BMM phi could stimulate mixed lymphocyte reaction (MLR) proliferation across an I-A subregion difference, but not across I-J subregion differences. This contrasted with splenic M phi which stimulated MLR proliferation across both an I-A and I-J subregion difference. The apparent lack of I-J subregion determinants on BMM phi correlated with their ability to function as antigen-presenting cells. In these experiments, BMM phi effectively reconstituted the trinitrophenyl-specific IgM plaque-forming cell (PFC) response of B cells but not the primary burro red blood cell (BRBC)-specific IgM-PFC response of M phi-depleted spleen cells. When BMM phi were added to BRBC-primed T and B cells, they reconstituted the secondary IgG PFC response to levels obtained using splenic M phi. These experiments relate the differential expression of H-21 region determinants on antigen-presenting cells with their functional capacity.

The ability of an organism to distinguish self from nonself is determined by a cluster of genes located in the major histocompatibility complex. Recent advances in molecular genetics and cellular immunology have begun to elucidate the mechanisms responsible for immune response regulation. In this review article, the genetic organization of the murine and human major histocompatibility complexes and the manner by which their gene products modulate immune responsiveness are discussed.

The histologic features of a malignant clear cell acrospiroma were those of infiltrative local growth, frequent mitoses and angiolymphatic invasion. The histochemical and ultrastructural findings were similar to those reported for benign clear cell acrospriomas. Amputation of the leg and regional node dissection were required for clinical control. Evaluation of this case and review of the literature suggests that the malignant clear cell acrospiroma often behaves in an aggressive manner and frequently metastasizes. As a consequence, thereapeutic strategies should be appropriately planned.

Specific anti-Ia serum in combination with rabbit complement removed the B lymphocyte population normally responsive to LPS mitogenic stimulation. Significant inhibition of this proliferative response was also obtained by brief periods of cell pretreatment with anti-Ia antibodies, but not with specific anti-H-2K antibodies. The population of splenic B cells resistant to anti-Thy-1.2 serum and complement was blocked in a very similar manner by anti-Ia serum, but not by anti-H-2 serum.

Specific antisera were used for the purification of thymus dependent and thymus independent or bursa equivalent lymphoid cells in the mouse. Spleen cells from mice immune to sheep erythrocytes, a thymus dependent antigen, or to E. coli 055:B5 lipopolysaccharide, a thymus independent antigen, were treated with anti-θ (C3H) serum or anti-MBLA serum and complement prior to their adoptive transfer into lethally irradiated syngeneic recipients. Syngeneic thymocytes, bone marrow cells, or spleen cells from nonimmune donors were appropriately added to antiserum treated cells prior to transfer. The secondary response to these antigens was assayed in recipient spleens six days after cell transfer. The kinetics of the primary response to SRBC was investigated as to its effect on origin of specific hyper-reactive T or B lymphoid cells. The adoptive response to CPS originated in the B lymphoid cell population. Immunologic memory to CPS was demonstrated in recipients of immune cells, compared to recipients of normal cells, by a five fold increase in antibody forming cells. The IgM and IgG adoptive immune response to high doses of SRBC depended upon an increased number of specifically hyper-reactive T-lymphoid cells to facilitate cooperation between T and B lymphocytes. High doses of SRBC initially stimulated T cell memory but at 42 days after priming an increased number of specifically hyper-reactive B lymphoid cells were present.

Mouse antiserums prepared against Ia antigens, which are products of I (immune response) region genes of the H-2 complex, can inhibit both primary (immunoglobulin M) and secondary (immunoglobulin G) immune responses in vitro by mouse spleen cultures to heterologous erythrocytes. Antiserums directed specifically at products of either the H-2K or H-2D loci have no effect on this response.

Analysis of the immune response of a panel of intra-I-region recombinant mouse strains to LDH-B and MOPC-173 demonstrated that B10.ASR7 (H-2as3) and B10.BASR1 (H-2as4) failed to mount T-cell-proliferative responses to MOPC-173 and LDH-B, respectively. To localize the level of the immune response defect in the B10.BASR1 strain, B10.BASR1 macrophages were shown to be incapable of presenting LDH-B to immune responder B10.ASR7 T cells. These results were confirmed using alloreactivity-depleted and (B10.ASR7 X B10.BASR1)F1 immune T cells. Failure of these strains to respond was shown not to be the result of T cell suppression, because cyclophosphamide and anti-Lyt-2.2-plus-complement treatments did not restore responsiveness. Furthermore, B10.BASR1 macrophages were incapable of educating naive responder T cells in vitro to LDH-B--however, naive nonresponder B10.BASR1 T cells could be educated by responder macrophages to LDH-B in vitro. These results suggest that the failure of B10.BASR1 to respond to LDH-B reflects a defect at the macrophage-T cell interaction level, perhaps related to expression of unique I-A molecules created by intra-I-region recombinatorial events.

The concept of regional chemotherapy for metastatic and primary liver cancer has been widely tested since its introduction in the 1950s [1–18]. From these numerous reports it was clear that the potential for success, as measured by improved survival, was dependent upon overcoming a number of technical problems. These technical problems significantly limited the duration of regional drug delivery [4–6, 10–18]. Early in 1979, we had the opportunity to adapt a totally implantable drug delivery system (Infusaid, Corporation, Norwood, MA.) for hepatic artery chemotherapy [19–23], Over the past five years we have implanted this device in over 200 patients [23–27]. Based on this experience, a number of critical technical axioms appear paramount to successful treatment. Clearly, the most important of these observations has been the necessity for attaining total liver perfusion and the importance of avoiding extrahepatic perfusion.

Genetic restrictions operative in macrophage-T-cell interactions have been shown to reside in the I region of the mouse H-2 major histocompatibility complex (1). To date, only four immunoprecipitable I region products have been identified, Aα, Aβ, Eα, and Eβ (Ae). However, these existing α-β chain combinations do not generate sufficient numbers of immunoregulatory determinants to account for previously described patterns of Ir-gene restriction. Therefore, we have begun to probe for I-region products of the central portion of this complex using intra-I-region recombinant mouse strains and nominal antigens that appear to be controlled by Ir genes in this central region. In this paper, we describe the genetic and serological separation of the Ir-genes controlling the T-cell proliferative responses to LDH-B and MOPC-173 and discuss the implications of these results.

A model for hepatic arterial chemotherapy studies using large dogs and an implantable infusion pump has been developed. Using this technique near complete perfusion (greater than 90%) of the liver can be achieved in vivo as determined by hepatic arterial perfusion scintigraphy with technitium 99m macroaggregated albumin. The system is reliable and has been in use for a total of 1353 days (mean of 104 days, range 52-239) in 13 dogs. Pump implantation causes no apparent acute liver damage based on pre- and post-operative alkaline phosphatase and serum glutamic-pyruvic transaminase determinations and does not affect the general mobility or behavior of the animals. Careful placement of the catheter and attention to the physicochemical properties of the solutions loaded are factors contributing to the success of the model. The model permits comprehensive preclinical pharmacokinetic and toxicologic studies of new or preexistent chemotherapeutic agents in the same device that will be used for later administration in human subjects. By providing the means to examine and develop new treatment modalities, it enables the design of even more potent cytotoxic therapy directed into the tumor vascular bed.

Negative regulation of the immune response is mediated by distinct subpopulations of T lymphocytes (1–6). Current information suggests that at least three separate suppressor Tcells (Ts) and their respective mediators (TsF) are involved in a defined sequence of events. While the mechanisms by which these TsF effect suppression remain unclear, it is important to note that many of the described TsF not only contain an I-J major histocompatibility complex (MHC) determinant but must react with an MHC-controlled gene product on an acceptor cell.

Pneumonia developed in 33 of 266 renal transplant recipients while they were receiving immunosuppressive therapy. Clinical factors were compared for patients with pneumonia and the control group of 220 transplant recipients without pneumonia. The diagnosis was usually established roentgenographically. Most cases of pneumonia were of bacterial origin and occurred within three months after transplantation. Pneumonia occurring during the first two postoperative weeks had no fatal outcomes. Patients with pneumonia occurring three to 12 weeks after transplantation had significantly greater leukopenia (P less than .05) and more therapy for allograft rejection (P less than .01) than the control group. Cases of fungal pneumonia developed later, were preceded by rejection, and had a poor prognosis. The mortality was 51.5% for all cases of pneumonia. Early diagnosis, prompt administration of specific antimicrobial agents, and immediate cessation of immunosuppressive therapy should improve the survival rate.

Three fibrous histiocytomas, primary in skin, were studied by light and electron microscopy and by frozen section histochemistry. The term malignant was applied to cutaneous tumors which demonstrated aggressive multinodular local growth, including angioinvasion and/or extension into bone, muscle, and fascia. Metastases were not found. Strongly positive reactions for hydrolytic enzymes, particularly acid phosphatase will help differentiate malignant fibrous histiocytoma from most other primary soft tissue malignancies of skin. Electron microscopic studies reaffirm the presence of both histiocyte-like and fibroblast-like cells. Langerhans' granules were not identified. Primary malignant fibrous histiocytoma of skin may have a prognosis superior to homologous tumors arising in deeper soft tissue and the retroperitoneum.

Tc-99m-MAA hepatic arterial perfusion scintigraphy ( HAPS ) using a totally implanted drug delivery system was employed for hepatic arterial chemotherapy in 147 patients (335 studies). Complete perfusion of the involved liver was seen in 88% of patients initially [more so in those with normal hepatic vascular anatomy (93%) than those with vascular variants (79%)] and remained good on follow-up. In 67 consecutive patients (95 studies), arteriovenous shunting to the lung ranged from 0.4 to 32% (mean, 6.2% +/- 4.1 S.D.). Uptake at the tip of the catheter was increased in 20% of patients, but good perfusion was usually maintained. A significant decrease in hepatic and/or extrahepatic perfusion associated with a "hot spot" at the tip of the catheter indicated hepatic arterial thrombosis. Extrahepatic perfusion was seen in 14% of cases, usually in the distribution of the stomach, small bowel, and spleen. Significant symptoms of drug toxicity were seen in 70% of patients with extrahepatic perfusion, compared to 19% of those without it.

Genes located in the I region of the H-2 complex control a system of lymphocyte alloantigens (Ia) which are expressed on subpopulations of T and B cells. Specific anti-Ia serum plus rabbit complement removed the B-lymphocyte population responsive to the mitogen LPS and the subpopulation of T cells responsive to Con-A. Lymphocytes sensitive to PHA or leucoagglutinin were not removed by anti-Ia serum and complement. Significant inhibition of the proliferative response to LPS was also obtained by brief periods of cell pretreatment with anti-Ia antibodies without complement. This inhibition was specific with the appropriate anti-Ia serum and did not occur with anti-H-2K sera or when cells of a different I region were pretreated.

Genetic restrictions operative in macrophage-T cell interactions have been shown to reside in the I region of the mouse H-2 major histocompatibility complex (1,2). Previous experiments to determine the role of Ia antigens in macrophage-T cell interactions have used macrophage isolated from spleen or peritoneum, preparations which contain a heterogeneous population of macrophage (3–5). It has been shown that only macrophage populations which express Ia are capable of presenting antigens to immune cells (4,5). Therefore, the use of a macrophage preparation homogeneously expressing I subregion antigens would afford a valuable opportunity to examine the role of Ia antigens in the regulation of the immune response. The use of murine bone marrow derived macrophage (BMDM) as a homogeneous source of antigen-presenting cells has been described by our laboratory (6). This present study characterized the MBDM for the expression of H-2I region gene products.

Adherent splenic macrophages contain a subpopulation which expresses an Ia determinant. This Ia positive accessory cell is required for the development of a primary in-vitro antibody response to a T cell dependent antigen by murine lymphoid cells. Genes controlling Ia antigen(s) on this subset of functional macrophages map to the I-J and I-E subregions. Antibodies specific for the I-J subregion determinant (s) are also capable of blocking the function of macrophages in the in-vitro humoral response.

Publisher Summary The H-2 gene complex is a part of the IXth linkage group on the 17th chromosome of the mouse. The complex is comprised of five regions, denoted in order from the centromeric end, K, I, S, G, and D. Cell-bound and soluble molecules reactive directly or indirectly with anti-Ia-sera involved in a number of immune phenomena. The function of the I region is very complex. This complexity reflects either multiple products of multiple I region genes, each with a distinct role and reactive with a distinct population of anti-la antibodies, or diverse manifestations of a very few Ia-reactive gene products, which play a very central role in immune processes. Ia antigens are predominantly expressed on lymphoid cells. Among the lymphoid cells, Ia antigens are most readily detected on B cells. The chapter discusses the ability of anti-la sera to block the mitogenic responses of lymphocytes or to eliminate mitogen-sensitive lymphoid cell populations.

Mononuclear phagocytes exert a major regulatory influence on many lymphocyte functions, including antibody production, lymphocyte proliferation, and the production of lymphokines (reviewed in Reference 1). Highly suppressive macrophages can be induced in mice by injection of a variety of agents such as C. parvum, BCG and pyran copolymer. Such in vivo stimulation concomitantly enhances macrophage tumoricidal activity in vitro and this observation led to the belief that a common activation mechanism underlay both functions (2–3). Unstimulated peritoneal macrophages also express suppressor activity (2,4) and low but significant levels of tumoricidal activity (5). This “natural” cytotoxicity can be highly enhanced by in vitro expo-sure to lymphokines, interferons, bacterial endotoxins and other substances (6–8). in vitro modulation of macrophage suppression with the same agents that enhance tumoricidal activity would help verify the hypothesis of a common regulation for the two activities. We now summarize our recent observations on the possibility of distinguishing the mechanism of regulation of macrophage cytotoxicity from that controlling suppression.

We and others have shown that treatment of antigen presenting cells with alloantiserum restricted to the I-A subregion inhibits their ability to present the terpolymer GAT to immune T cells (1–3). The inhibition is independent of complement and antiserum recognizing other H-21 subregions has no effect (Figure 1). These results have been interpreted to suggest that anti I-A antibodies mask the Ia antigen (Ir gene product) and, thus, block the T cell receptor(s) from recognizing either Ir gene product and specific antigen in complex or separately (4).

The Committee on Issues of the Association for Academic Surgery surveyed the Association's membership, surgical department chairmen, and university hospital emergency department directors as to their attitudes about the role of surgeons and emergency medicine specialists in emergency care. Major differences in attitudes exist between surgeons and nonsurgeons regarding the surgeon's role in the emergency department. Although surgeons want to preserve a dominant role in emergency care, they have little interest in being in charge of emergency wards on a day to day basis. Emergency medicine specialists have a tendency to function independently, even to the point of independently performing emergency surgical procedures. In emergency departments led by nonsurgeons there is decreased participation of surgical house staff in the resuscitation of the critically injured patients. This may result in inadequate training of surgical residents in acute trauma care and ultimately result in lowered overall standards of care in critically ill patients. An important question is whether surgeons can continue to abdicate their present reponsibilities in the emergency ward and yet maintain their essential role in the preoperative care of the emergency patient.

A totally implanted system for improved central venous access has been investigated in 20 patients with cancer (six with solid tumors, four with leukemia, and 10 with lymphomas) who were treated with aggressive chemotherapy regimens and who lacked peripheral venous sites. The system is implanted using local anesthesia and consists of a subcutaneous injection port connected to a Silastic catheter threaded through the subclavian vein into the superior vena cava. Injections and continuous infusions (for up to three weeks) of virtually all classes of antineoplastic agents, antibiotics, blood components, and intravenous solutions were administered through the system. The system was filled with heparinized saline and not otherwise flushed between uses. The system has remained functional for periods exceeding 450 days (mean 235 days). There was no significant local irritation and no system became infected. None of 18 large-bore catheters (0.63 mm lumen) became occluded (seven to 300 days), whereas five of six small-bore catheters (0.38 mm lumen) became occluded (90 to 420 days). Three of the occluded systems were replaced. Acceptance has been excellent, and patients have had no impediment to normal activities. This system appears to be an alternate means of safe and reliable central venous access with improved convenience and cosmetic acceptability.

Intraarterial infusion chemotherapy has not been widely accepted for the treatment of head and neck cancer due to the high rate of complications it involves. To avoid these complications, a totally implantable infusion pump has been developed to achieve continuous low-level drug delivery for long periods of time. The pump is implanted in a subcutaneous pocket and connected to a permanent, indwelling, arterial catheter. It can be repeatedly refilled with chemotherapeutic agents by hypodermic needle injection through the skin and through a self-sealing septum located at the entry to the pump. Refilling the pump recharges an inexhaustible power source for the next delivery cycle. Preliminary results suggest that long term intraarterial infusion chemotherapy for the treatment of head and neck cancer is practical for outpatients.

Efforts in our laboratory to establish probes for defining new recombinatorial events demonstrated that the primary in vitro immune response to the TI-2 antigen TNP-Ficoll was under strict Ir-gene regulation. Further investigation indicated that the response was controlled by two complementing loci, the first located in the I-A subregion with high responder alleles s, d, and k, and a second located in or to the right of the I-E subregion where the b and. s alleles resulted in high responder animals. High responder alleles must be present at both loci to produce a high responder phenotype. Results of these experiments are shown in Table I.