Immunohistochemical detection of retroviral-P15E-related material in carcinomas of the head and neck

A Systematic Review of Expression and Immunogenicity of Human Endogenous Retroviral Proteins in Cancer and Discussion of Therapeutic Approaches

Human endogenous retroviruses (HERVs) are remnants of ancient retroviral infections that have become fixed in the human genome. While HERV genes are typically silenced in healthy somatic cells, there are numerous reports of HERV transcription and translation across a wide spectrum of cancers, while T and B cell responses against HERV proteins have been detected in cancer patients. This review systematically categorizes the published evidence on the expression of and adaptive immune response against specific HERVs in distinct cancer types. A systematic literature search was performed using Medical Search Headings (MeSH) in the PubMed/Medline database. Papers were included if they described the translational activity of HERVs. We present multiple tables that pair the protein expression of specific HERVs and cancer types with information on the quality of the evidence. We find that HERV-K is the most investigated HERV. HERV-W (syncytin-1) is the second-most investigated, while other HERVs have received less attention. From a therapeutic perspective, HERV-K and HERV-E are the only HERVs with experimental demonstration of effective targeted therapies, but unspecific approaches using antiviral and demethylating agents in combination with chemo- and immunotherapies have also been investigated.

Cancer Associated Endogenous Retroviruses: Ideal Immune Targets for Adenovirus-Based Immunotherapy

Cancer is a major challenge in our societies, according to the World Health Organization (WHO) about 1/6 deaths were cancer related in 2018 and it is considered the second leading cause of death globally. Immunotherapies have changed the paradigm of oncologic treatment for several cancers where the field had fallen short in providing competent therapies. Despite the improvement, broadly acting and highly effective therapies capable of eliminating or preventing human cancers with insufficient mutated antigens are still missing. Adenoviral vector-based vaccines are a successful tool in the treatment of various diseases including cancer; however, their success has been limited. In this review we discuss the potential of adenovirus as therapeutic tools and the current developments to use them against cancer. More specifically, we examine how to use them to target endogenous retroviruses (ERVs). ERVs, comprising 8% of the human genome, have been detected in several cancers, while they remain silent in healthy tissues. Their low immunogenicity together with their immunosuppressive capacity aid cancer to escape immunosurveillance. In that regard, virus-like-vaccine (VLV) technology, combining adenoviral vectors and virus-like-particles (VLPs), can be ideal to target ERVs and elicit B-cell responses, as well as CD8⁺ and CD4⁺ T-cells responses.

Covalent linking of proteins and cytokines to suture: Enhancing the immune response of head and neck cancer patients

BACKGROUND

The immune system of advanced stage head and neck cancer patients is frequently suppressed. Poor immune function has been correlated with poor clinical outcome. Immunotherapeutic strategies have been previously attempted in an effort to enhance immune function and improve survival. Previous studies have shown surgical suture can be transformed into an immune stimulant capable of activating the T lymphocytes of cancer patients. The development of a process for covalently linking proteins and cytokines to suture could have enormous potential for the in vivo manipulation of the immune system.

HYPOTHESIS

We hypothesize proteins and cytokines can be covalently linked to surgical suture while preserving their functional properties.

STUDY DESIGN

Prospective study testing normal donor and head and neck squamous cell carcinoma (HNSCC) patient lymphocytes.

METHOD

Polyester suture was acid hydrolyzed followed by reacting with 1-ethyl-3(-3-dimethylamino propyl carbodiimide) (EDAC) to create a suture-EDAC intermediate. Next, selected proteins (horseradish peroxidase [HRP] or bovine serum albumin [BSA]) or cytokines (interleukin [IL]-2 or interferon [IFN]-gamma) were reacted with the suture-EDAC intermediate to test the covalent linkage of the selected protein or cytokine to suture. Functional activity of the linked proteins was measured spectrophotometrically. The linking of cytokines to suture was tested by stimulating normal donor peripheral blood lymphocytes (PBL) or HNSCC patients' lymphocytes. The functional activity was confirmed by proliferation, enzyme linked immunoadsorbent assay (ELISA), and phenotype expression of T cells. RESULTS The conditions for optimally linking a protein to polyester suture were defined using HRP as a model protein. HRP retained its enzymatic activity. The optimal conditions for linking IL-2 or IFN-gamma were defined. The covalently linked cytokines retained their immune enhancing properties for stimulating PBL and lymph node lymphocytes (LNL) from HNSCC patients to proliferate, generate a TH1 immunologic profile of cytokines (IL-2, IL-12, IFN-gamma), and stimulate T lymphocytes.

CONCLUSION

This is the first report to demonstrate that cytokines can be covalently linked to surgical sutures and retain their immune-stimulating properties. Proteins linked to suture also retained their enzymatic activity. The clinical implications of functionally active cytokines or proteins linked to surgical suture may be very significant in the future for manipulating the immune system in vivo or enhancing wound healing.

Plattenepithelkarzinome des Kopf-Hals-Bereichs

Biologic therapies able to induce or up-regulate anti-tumor immune responses could represent a complementary approach to improve the conventional treatment of squamous cell carcinomas of the head and neck (SCCHN). Patients with SCCHN are frequently immunocompromised due to the elimination and dysfunction of critical immune effector cells. Therefore, it might be necessary to restore these immune functions to allow for the generation of effective anti-tumor host responses. Simultaneously, to prevent tumor escape from immunological recognition and destruction, it might also be necessary to alter antigenic and immunogenic attributes of the malignant cells. The present overview summarizes general aspects, historical data, and recent advances in the field of immunotherapy of SCCHN, including non-specific immune stimulation, transfer of immunocompetent cells, gene therapy, use of monoclonal antibodies, and anti-cancer vaccines.

Targeting the immune system: novel therapeutic approaches in squamous cell carcinoma of the head and neck

Despite advances in surgery, radiotherapy, and chemotherapy, the overall survival rates for patients with squamous cell carcinoma of the head and neck (SCCHN) have not changed over the last decades. Clearly, novel therapeutic strategies are needed for this cancer, which is highly immunosuppressive. Therefore, biologic therapies able to induce and/or up-regulate antitumor immune responses could represent a complementary approach to conventional treatments. Because patients with SCCHN are frequently immunocompromised due to the elimination or dysfunction of critical effector cells of the immune system, it might be necessary to restore these immune functions to allow for the generation of more effective antitumor host responses. Simultaneously, to prevent tumor escape, it might be necessary to alter attributes of the malignant cells. The present review summarizes recent advances in the field of immunotherapy of SCCHN, including techniques of nonspecific immune stimulation, the use of monoclonal antibodies, advances in adoptive immunotherapy and genetic engineering, as well as anticancer vaccines. These biologic therapies, alone or in combination with conventional treatment, are likely to develop into useful future treatment options for patients with SCCHN.

Immunotherapy with monoclonal antibodies directed against the immunosuppressive domain of p15E inhibits tumour growth

Immunosuppressive retrovirus-related proteins, like p15E, are involved in tumour-associated immunosuppression. In the present study we investigated whether such proteins could be used as targets in tumour immunotherapy using MoAbs. Immunotherapy was performed in mice inoculated with the Rauscher virus-transformed myeloid cell line RMB-1. RMB-1 cells express retroviral antigens at their cell surface. In order to obtain constant serum titres of MoAbs over a prolonged period of time during therapy, anti-p15E antibody-producing hybridoma cells were encapsulated in alginate and injected intraperitoneally in tumour-bearing mice. Using this technique, serum antibody titres of 50-100 micrograms/ml were obtained, which remained constant over a period of at least 3 weeks. Therapy experiments were performed using anti-p15E antibodies 19F8, which recognizes both cell surface-associated as well as circulating p15E, and ER-IS5, which did not react with surface-bound p15E beyond background, but which neutralizes circulating p15E. Inoculation of alginates containing anti-p15E hybridoma cell lines in RMB-1 tumour-bearing mice showed inhibition of tumour cell growth. In survival experiments, 19F8 cured eight of 23 tumour-bearing mice. The p15E neutralizing antibody ER-IS5 caused a significant longer survival, but therapy with this MoAb alone was not sufficient to cure the animals of the RMB-1 tumour.

Proliferation of hematopoietic cell lines induced by a soluble factor derived from human squamous cell carcinomas of the head and neck

The supernatant of a cell line of squamous cell carcinoma of the head and neck (SCCHN), PCI-50, was previously shown to induce activation, promote proliferation and increase antitumor cytotoxicity of freshly purified human natural killer (NK) cells and CD4+ T lymphocytes [Arch Otolaryngol Head Neck Surg (1994) in press]. This supernatant was found also to promote the growth of a variety of hematopoietic cell lines, including Jurkat, THP-1, K562, NK-92 or Epstein-Barr-virus-transformed B cell lines. The Jurkat cell line was selected as a reporter cell in an 18-h proliferation assay established to measure the growth-promoting activity of PCI-50 supernatant. The presence of soluble tumor-derived factors able to induce proliferation of Jurkat cells was demonstrated in the supernatant produced by several other SCCHN cell lines but not in that produced by a gastric cancer cell line (HR) or renal cell carcinoma line (5117G8). The growth-promoting PCI-50 supernatant was shown to contain 28 +/- 0.5 pg/ml interleukin-6 (IL-6) in vitro but was negative for interferon gamma, IL-1, IL-2, IL-4, tumor necrosis factor alpha, granulocyte/macrophage-colony-stimulating factor and IL-12. The addition of any of these recombinant cytokines to Jurkat cell cultures did not significantly promote growth, while PCI-50 supernatant was consistently growth-stimulatory. This supernatant neither enhanced intracellular Ca2+ concentration in Jurkat cells nor induced up-regulation of activation antigens on the cell surface, although it supported growth of Jurkat cells in the absence of IL-2. The growth-promoting activity in the PCI-50 supernatant was acid-labile at pH 2 for 4 h, heat-resistant at 96 degrees C for 1 h and sensitive to treatments with trypsin and pepsin. Preincubation of the PCI-50 producer cells with tunicamycin or cyclohexamide reduced the level of growth-promoting activity in the supernatant. A partial purification of this activity was achieved using Amicon filtration, chromatography on concanavalin-A-Sepharose and then a hydroxyapatite column and high-pressure liquid chromatography gel filtration. The partially purified glycoprotein had a molecular mass of 50-70 kDa, as determined by gel filtration.

PCR and reverse dot hybridization for the detection of endogenous retroviral transcripts

Two degenerated oligonucleotide primers, known to amplify a fragment of the pol gene in all retroviruses tested so far have been used to amplify pol related sequences from human genomic DNA. Cloning and sequencing these fragments confirm a retroviral relationship for most of them and define 96 groups on the basis of their internal similarity. 96 pol fragments were probed with PCR amplified cDNA in reverse dot hybridization to investigate pol related transcripts. PCR amplified genomic DNA served as a control for contamination of genomic DNA in the RNA preparations. Isopycnic centrifugation in cesium trifluoroacetate yielded RNA with the lowest possible amounts of contaminating DNA. This technique is a powerful and a well-controlled tool for the detection of endogenous retroviral transcripts and may be helpful for investigating the involvement of endogenous retroviruses in various diseases.

Comparison of retroviral p15E-related factors and interferon alpha in head and neck cancer

Head and neck squamous cell carcinomas (HNscc) produce low-molecular-mass factors (low-M(r) factors, M(r) < or = 25,000), which are antigenically related to the immunosuppressive retroviral transmembrane envelope protein p15E. These P15E-related tumour factors are thought to be responsible for some immunological impairments found in these patients (particularly the defective monocyte chemotaxis). A sequential and functional homology has been reported to exist between a bioactive fragment of interferon alpha (IFN alpha) and the putative immunosuppressive region of retroviral p15E (CKS-17). In this study we investigated (a) a possible functional and structural relationship between p15E and IFN alpha, and (b) the presence of and the relationship between p15E-related low-M(r) factors and IFN alpha in HNscc patients. We report the following results. (a) Recombinant human (rhu) IFN alpha was able to inhibit monocyte chemotaxis. (b) The anti-p15E antibodies crossreacted with rhuIFN alpha in a dot-blot technique; however, the anti-IFN alpha antibodies did not crossreact with disrupted murine leukaemia virus (p15E source). (c) Low-M(r) factors (n = 8-11) prepared from the sera of HNscc patients, which inhibit the monocyte chemotactic responsiveness, could be adsorbed by the anti-p15E antibodies as well as by the anti-IFN alpha antibodies. However, the abilities of the factors to adsorb to the two categories of antibodies (namely, anti-p15E and anti-IFN alpha) did not correlate. (d) Immunohistochemically we found IFN alpha-related epitopes, in almost all HNscc specimens studied (17/18), in locations distinctive from those of p15E-related factors. The anti-IFN alpha antibodies used in this study mainly reacted with basal epithelial cells close to the basal membrane, the prickle and granular cells of the squamous cell carcinomas. The anti-p15E antibodies mainly reacted with corneal layers, the granular and prickle cells, and did not react with basal epithelial cells. Our findings suggest that the immunosuppressive factors produced by HNscc cells are heterogeneous and p15E- and/or IFN alpha-related.

Macrophage and dendritic cell infiltration in head and neck squamous-cell carcinoma; an immunohistochemical study

A study was undertaken to help us reach a better understanding of the tumor-infiltrating pattern of lymphoid cells and in particular of monocyte-derived cells, namely the CD68+, acid-phosphatase-expressing scavenger macrophages and the MHC-class-II- and S100-antigen-presenting dendritic cells in head and neck squamous-cell carcinoma. In the stroma of the tumors distinctive small fields of lymphocytes were found, the T cell areas of these fields being intermingled with dendritic cells. Intra-epithelial dendritic cell infiltration was low. The infiltrative pattern of macrophages was similar to patterns described in earlier studies with substantial stromal invasion and inconsistent intra-epithelial invasion, but small granuloma-like structures of CD68+ macrophage-like cells, found in the stroma of tumors, have not been reported before. The histochemical localization of the tumor-infiltrated dendritic cells and macrophages supports the view that the former cells are involved in the sensitization to tumor antigens, whereas the latter cells are involved in tumor cytotoxicity/scavenging of tumor cell debris. Although it has been shown in the past that transmembranal (TM) factors (p15E-like factors) present in the serum and tumor of patients with cancer of the head and neck have suppressive effects on monocyte/macrophage/dendritic cell function, a relationship between the intensity of epithelial staining for TM factors and the infiltrative pattern of monocytes/macrophages/dendritic cells could not be demonstrated.

Dysfunction of monocytes and dendritic cells in patients with premature ovarian failure

PROBLEM

Due to the presence of ovarian antibodies it has been suggested that premature ovarian failure (POF) belongs to the autoimmune endocrinopathies. Monocytes and the monocyte-derived dendritic cells play a prominent role in the initial stages of endocrine autoimmune reactions: the accumulation of monocytes/dendritic cells and the clustering of dendritic cells in endocrine organs is one of the first phenomena of an autoimmune endocrinopathy.

METHOD

This report describes a study on (1) the chemotactic responsiveness of blood monocytes, and (2) the cluster capability of blood dendritic cells in POF patients. The monocyte chemotaxis was determined using the cell's capability to polarize (changes in shape determined by light microscopy) under the influence of the chemoattractant, N-formyl-methionyl-leucyl-phenylalanine (fMLP). The cluster capability of dendritic cells was tested by allowing the dendritic cells to form aggregates with allogenic lymphocytes in vitro.

RESULTS

The blood monocytes of 46% of a total of 28 POF patients showed a decreased fMLP induced monocyte polarization in comparison to healthy control values. None of the young female controls (N = 28) and postmenopausal women (N = 17), showed such a defective monocyte polarization. The blood dendritic cells of 36% of the POF patients showed a decreased cluster capability. Defects in monocyte polarization and dendritic cell clustering were not affected by therapies aimed at changes in the estrogen levels or gonadotropin levels of the patients [using estrogen substitution therapy, gonadotropin-releasing hormone (GnRH) analog, follicle-stimulating hormone (FSH)].

CONCLUSIONS

A redistribution of active monocytes and of active dendritic cells from the peripheral blood to the ovaries may be the cause of the described abnormalities. Since similar abnormalities in monocyte function and dendritic cell function have been described in Graves' disease and type I diabetes, the data strengthen the view that POF is one of the endocrine autoimmune diseases.

The presence of immunosuppressive 'p15E-like' factors in the serum and urine of patients suffering from malign and benign breast tumours

Certain types of tumours are capable of producing factors inhibiting mononuclear phagocyte chemotaxis which may contribute to defects in immunosurveillance. In head and neck cancer these factors are said to be related to the retroviral protein p15E. This study examines the presence of p15E-like factors in serum and urine of patients with malign and benign breast tumours. Thirty patients with breast cancer, 29 patients with benign breast masses, and 28 healthy controls were tested blindly with the monocyte polarization assay, using N-formyl-methionyl-leucylphenylalanine as chemo-attractant. The low molecular weight fractions prepared of sera of the malign tumour patients inhibited the monocyte polarization significantly (mean inhibition 34%, s.d. = 12) compared with those of benign tumour patients (15%, s.d. = 7) and of controls (14%, s.d. = 6). The observed inhibitory effects on the monocyte polarization could be compensated by MoAbs reactive to p15E-related antigens. The mean difference between the polarization inhibition with and without anti-p15E adsorption (the 'p15E-like factor-induced inhibition') was 25% (s.d. = 13) in the breast cancer group, compared with 7% (s.d. = 5) in the benign tumour patients and 5% (s.d. = 4) in the healthy control group. Surgical removal of the tumours resulted in a restoration of the monocyte polarization in 20/23 (87%) patients of the breast cancer group. Results testing preoperative urine samples correlated well with those of corresponding sera. These data give additional support to the concept that tumour-derived p15E-like factors are responsible for the inhibitory effect on monocyte chemotaxis in breast cancer patients, and that these factors can be found in serum as well as in urine.

Expression of a suppressive p15E-related epitope in colorectal and gastric cancer

mRNA for the suppressive epitope of p15E was found to be present in 24 of 30 samples of human colorectal cancer and in all four specimens of gastric cancer. mRNA for p15E was seldom seen in nonmalignant colonic or gastric mucosa but, when present, was associated with inflammatory or pre-malignant conditions of the digestive tract. Synthetic peptides derived from the conserved p15E sequence were found to suppress some aspects of the immune response implicated in anti-tumour activity. These data suggest that a p15E-related material with immunomodulatory properties is elaborated within human tumours, either by the tumour itself or as a normal component of the endogenous anti-tumour reaction.

Retroviral p15E-related serum factors and recurrence of head and neck cancer

Surgical removal of head and neck squamous cell carcinoma (HNSCC) restores the defective monocyte polarization found in patients with HNSCC. Since HNSCC contain p15E-like low molecular weight factors < 25 kD (LMWF) capable of suppressing N-formyl-methionyl-leucylphenylalanine (fMLP)-induced monocyte polarization, it is likely that HNSCC removal eradicates the production site of p15E-like factors. This report describes a prospective follow-up study on the levels of bioactive p15E-like serum factors for a period of 2 years in nine patients with HNSCC who had no recurrence and 11 patients with HNSCC who showed residual or recurrent disease after treatment. In the group of patients without recurrent disease p15E-like bioactivity gradually decreased and eventually became negative. In patients with recurrent/residual disease p15E-like bioactivity remained high or even became positive before or at the time of diagnosing tumour recurrence. This study strongly supports the concept that HNSCC tumours are the production site of p15E-like immuno-suppressive factors and indicates that serum p15E-like factors may be used for future studies on early serum markers for recurrent/residual disease developing in the first year after treatment.

Depressed monocyte polarization and clustering of dendritic cells in patients with head and neck cancer: in vitro restoration of this immunosuppression by thymic hormones

The in vitro restoring effects of a thymic hormone preparation, TP-1, on defective monocyte and dendritic cell function in patients with head and neck squamous cell carcinoma (HNSCC) have been examined. The N-formylmethionyl-leucyl-phenylalanine (fMLF)-induced polarization of monocytes isolated from the peripheral blood was significantly lower (a mean of 19%) than the polarization of monocytes isolated from healthy controls (a mean of 33%). After the in vitro addition of TP-1 this defective polarization was improved to the normal value of 33% polarized monocytes. The capability of dendritic cells prepared from the blood to form cellular clusters with allogeneic cells was impaired in 26/44 patients. In vitro addition of TP-1 again had restoring effects. The original defective dendritic cell clustering of 97 clusters/six microscopic fields (mean) was improved to a value of 121 clusters. The defects in monocyte polarization and clustering of dendritic cells could be ascribed to the presence in serum of a tumor-derived low-molecular-mass factor low-M(r) factor; < 25 kDa) sharing structural homology with p15E, the capsular protein of murine and feline leukemogenic retroviruses. The incubation of low-M(r) factor from the serum of HNSCC patients with healthy donor monocytes resulted in a significantly higher inhibition of fMLF-induced monocyte polarization than did incubation with control low-M(r) factor (a mean of 42 versus 16% inhibition). This suppressive effect of patient low-M(r) factor was abrogated with a mixture of two monoclonal antibodies against p15E as well as with TP-1. The observations here reported on the in vitro effects of TP-1 on depressed monocyte and dendritic cell function in HNSCC have provided one of the rationales for a TP-1 therapeutic pilot trial recently started in HNSCC patients.

Defects in monocyte polarization and dendritic cell clustering in patients with Graves' disease. A putative role for a non-specific immunoregulatory factor related to retroviral p15E

A depressed chemotactic responsiveness of monocytes and a depressed cluster capability of dendritic cells have been found in diseases such as chronic purulent infections of the respiratory tract and in various types of malignancies. These impairments in monocyte and dendritic cell function could be ascribed to the action of a low molecular weight factor (LMWF; less than 25 kDa) circulating in the serum of the patients. The factor, which seems to be a non-specific immunoregulatory factor, shares a structural homology with p15E, the capsular protein of murine and feline leukaemogenic retroviruses. In order to study the chemotactic responsiveness of monocytes and the cluster capability of dendritic cells of Graves' patients, monocytes were isolated from the peripheral blood and dendritic cells were prepared from these peripheral blood monocytes by exposure to metrizamide. Monocytes were studied for their chemotactic responsiveness measuring their capability to polarize (morphological changes determined by light microscopy) after stimulation with the chemoattractant fMLP. Dendritic cells were studied for their capability to form clusters with allogeneic lymphocytes. A defective fMLP-induced monocyte polarization was found (16 vs 37% in healthy controls), whereas the dendritic cells showed a defective clustering (60 clusters vs 151 clusters in healthy controls). The effect of fractions of less than 25 kDa prepared from the serum of Graves' patients on healthy donor monocytes and dendritic cells was studied to test the presence of p15E-like factors. The serum fractions had a significant inhibitory effect on monocyte polarization and dendritic cell clustering.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunosuppressive retroviral-related factors in sera of patients with head and neck cancer

The chemotactic responsiveness of mononuclear phagocytes has often been found defective in patients with various malignancies. We have previously reported a defective chemotactic responsiveness in patients with head and neck cancer. Low-molecular-weight factors (LMWFs) have been isolated from tumors and can be held responsible for the inhibitory effect on monocyte chemotactic responsiveness. It is an intriguing new finding that these LMWFs can be neutralized by antibodies reactive to P15E, a structural envelope protein of murine leukemia retroviruses. In this report we describe a relatively easy and rapid method for the detection of immunosuppressive P15E-like factors in the sera of patients with head and neck cancer. The test is based on the monocyte polarization assay. Although only nine head and neck cancer patients were included in this study, the findings indicate that the test might be of value for clinical application. An early detection of a recurrence after treatment might be possible by the finding of a reappearance of the P15E-like factors in patients' sera during follow-up.

Beneficial effects of the thymic hormone preparation thymostimulin in patients with defects in cell-mediated immunity and chronic purulent rhinosinusitis. A double-blind cross-over trial on improvements in monocyte polarization and clinical effects

Twenty patients with chronic purulent rhinosinusitis were treated with TP-1 (Serono; 1 mg/kg body weight), in a double-blind cross-over trial. TP-1 was administered by daily i.m. injections for the first 14 days followed by two injections/week for 6 further weeks. The patients were immunologically special in that they had defects in their cell-mediated immune system. Fourteen showed a decreased chemotactic responsiveness of their peripheral blood monocytes as measured in the polarization assay. This defective function can probably be ascribed to the presence in serum of low molecular weight factors (LMWFs; less than 25 kD). As reported earlier, this factor shows a structural homology to the envelope protein of murine and feline leukaemia virus (P15E). Thirteen patients showed a defective delayed-type hypersensitivity (DTH) skin test reactivity towards candidin and/or streptokinase-streptodornase (Sk/Sd) antigen, 14 had a defective MIF production from their peripheral blood lymphocytes towards candidin, Sk/Sd and/or Haemophilus influenzae antigen. Eighteen patients completed the TP-1 trial and showed clinical improvements: 12 out of 15 were feeling better during TP-1 therapy and the nasal mucosa showed on inspection absent mucopurulent secretion in 13 patients. Positive bacterial culture rates for the nose decreased from 14 out of 16 to five out of 15. Placebo treatment had no significant effects. The clinical improvements were accompanied by a better performance of the cell-mediated immune system; the most significant effects were recorded in the monocyte polarization assay. The suppressive P15E-like LMWFs in serum clearly decreased during TP-1 treatment. In vitro TP-1 neutralized the immunosuppressive effect of the LMWFs. The restoring effects of TP-1 on monocyte polarization and its neutralizing activity of P15E-like LMWFs could explain the beneficial effects of thymic hormone treatment reported in adults with clinical signs of immunodeficiency in the presence of a full T cell repertoire.

Immunoscintigraphy in laryngeal and pharyngeal carcinomas using indium-111 labelled monoclonal antibody

Localization of primary tumors, metastases or recurrences in 13 consecutive patients with histological verification of squamous cell or adenocarcinoma was determined with radioimmunoscintigraphy using monoclonal radiolabelled anti-CEA-antibody. In 12 of the 13 cases, immunohistochemical stainings were positive for CEA. Correct radioimmunoscintigraphic localization was obtained in 15 of the 19 surgically verified tumor sites. There were two positive scintigraphic findings which could not be verified during one year follow-up. The CEA serum concentrations were with one exception normal in all patients, showing that the serum CEA level does not predict the possible benefit from anti-CEA radioimmunoscintigraphy.