Association of Baseline Tumor-Specific Neoantigens and CD8+ T-Cell Infiltration With Immune-Related Adverse Events Secondary to Immune Checkpoint Inhibitors

PURPOSE

Recent evidence has shown that higher tumor mutational burden strongly correlates with an increased risk of immune-related adverse events (irAEs). By using an integrated multiomics approach, we further studied the association between relevant tumor immune microenvironment (TIME) features and irAEs.

METHODS

Leveraging the US Food and Drug Administration Adverse Event Reporting System, we extracted cases of suspected irAEs to calculate the reporting odds ratios (RORs) of irAEs for cancers treated with immune checkpoint inhibitors (ICIs). TIME features for 32 cancer types were calculated on the basis of the cancer genomic atlas cohorts and indirectly correlated with each cancer's ROR for irAEs. A separate ICI-treated cohort of non-small-cell lung cancer (NSCLC) was used to evaluate the correlation between tissue-based immune markers (CD8+, PD-1/L1+, FOXP3+, tumor-infiltrating lymphocytes [TILs]) and irAE occurrence.

RESULTS

The analysis of 32 cancers and 33 TIME features demonstrated a significant association between irAE RORs and the median number of base insertions and deletions (INDEL), neoantigens (r = 0.72), single-nucleotide variant neoantigens (r = 0.67), and CD8+ T-cell fraction (r = 0.51). A bivariate model using the median number of INDEL neoantigens and CD8 T-cell fraction had the highest accuracy in predicting RORs (adjusted r2 = 0.52, P = .002). Immunoprofile assessment of 156 patients with NSCLC revealed a strong trend for higher baseline median CD8+ T cells within patients' tumors who experienced any grade irAEs. Using machine learning, an expanded ICI-treated NSCLC cohort (n = 378) further showed a treatment duration-independent association of an increased proportion of high TIL (>median) in patients with irAEs (59.7% v 44%, P = .005). This was confirmed by using the Fine-Gray competing risk approach, demonstrating higher baseline TIL density (>median) associated with a higher cumulative incidence of irAEs (P = .028).

CONCLUSION

Our findings highlight a potential role for TIME features, specifically INDEL neoantigens and baseline-immune infiltration, in enabling optimal irAE risk stratification of patients.

An Orally Administered Nonpathogenic Attenuated Vaccine Virus Can Be Used to Control SARS-CoV-2 Infection: A Complementary Plan B to COVID-19 Vaccination

Background

Coronavirus disease 2019 (COVID-19) vaccination has substantially altered the course of the pandemic, saving tens of millions of lives globally. The problem is that despite such spectacular results, vaccination alone will not be able to control the COVID-19 pandemic because of the rapid evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) even in vaccinated human populations. Therefore, the development of a post-infection, broad-based, orally administered antiviral therapy that would complement vaccination efforts is urgently needed.

Methodology

The so-called viral superinfection therapy (SIT) administers a nonpathogenic attenuated double-stranded RNA (dsRNA) vaccine virus drug candidate, the infectious bursal disease virus serotype R903/78 (IBDV-R903/78) that activates the interferon (IFN) genes, which are the natural, antiviral defense system of host cells.

Results

Here we present two cases of properly vaccinated (with BNT162b2-Pfizer) and booster-dosed COVID-19 patients with vaccine breakthrough infections whose disease duration was shortened to a few days by oral SIT.

Conclusions

SIT has already been demonstrated to be safe and effective against five different families of viruses, hepatitis A virus, hepatitis B virus, hepatitis C virus, SARS-CoV-2, and herpes zoster virus. The R903/78 drug candidate is simple to manufacture and easy to administer in an outpatient setting. The expected cost of SIT will be affordable even in resource-limited countries.

A clinically validated, broadly active, oral viral superinfection therapy could mitigate symptoms in early-stage COVID-19 patients

More than 200 viruses infect humans but drugs are available for fewer than ten. To narrow the gap between 'bugs and drugs', a paradigm shift is required. The "one drug, one bug" approach should be supplemented by the "one drug, multiple bugs" strategy such that the host is targeted rather than the virus. The revolutionary viral superinfection therapy (SIT) activates the antiviral interferon gene natural defense system of host cells from within by an attenuated infectious bursal disease virus (IBDV) that releases its double-stranded RNA (dsRNA) cargo inside the cells. An attenuated IBDV vaccine strain has resolved hepatitis A virus infection (HAV) in marmoset monkeys and hepatitis B and C virus infections (HBV/HCV) in 42 patients with acute HBV or HCV. SIT was also safe and effective in four hepatically decompensated, chronically infected HBV and HCV patients. The proof-of-principle of SIT was demonstrated first in a 43-year-old male patient with COVID-19. Three doses of IBDV (3x106 IU) alleviated most of his COVID-19 symptoms, even the sense of smell returned within a week. Two additional COVID-19 patients responded similarly to oral treatment with IBDV. Furthermore, a severe herpes zoster ophthalmicus with orbital edema was healed within few days by combination of acyclovir and 7 doses IBDV (7x106 IU). IBDV is simple to manufacture and will be affordable even in resource limited settings. Acid resistant IBDV can be orally administered in an outpatient setting providing the greatest ease of dosing and the highest chance of patient compliance. Under an Emergency Use Authorization, the broad-based IBDV drug candidate could be tested immediately in clinical trials and rapidly distributed to millions of early-stage patients with COVID-19. The German Paul Ehrlich Institute supports such a phase I safety study for persons acutely infected with SARS‑CoV-2. An expert team of the US National Institutes of Health-sponsored ACTIV public-private partnership came to the conclusion that the IBDV drug candidate shows merit as a potential treatment for COVID-19 and an FDA approved clinical trial is in the pipelines in Los Angeles.

Healing of Severe Herpes Zoster Ophthalmicus Within a Few Days: An Autobiographical Case Report

Herpes zoster (shingles) is caused by the herpes zoster virus and is characterized by pain and unilateral vesicular rash that typically affects one dermatome. Symptoms tend to resolve over 10-15 days. This case report describes the 75-year-old author’s herpes zoster ophthalmicus (HZO) accompanied by severe orbital edema. The upper eyelid and the proximal nasal area were also affected. The author felt an intermittent throbbing pain in more than three dermatomes including the frontal, orbital, temporal, and occipital/nuchal areas. Since the prodromal and erythematous phase started with atypical signs, conventional acyclovir treatment was administered only 96 hours after the appearance of the first symptoms. Acyclovir treatment was therefore complemented with the experimental viral superinfection therapy (SIT). Superinfection is a host-directed therapy, during which the non-pathogenic avian live-attenuated infectious bursal disease virus (IBDV) vaccine delivers its double-stranded RNA (dsRNA) cargo to host cells and activates their natural antiviral interferon (IFN) gene defense system from within. Most symptoms resolved within five days. Given the author's advanced age of 75 years, such speedy recovery is unlikely to be explained by the belated acyclovir treatment alone.

Therapeutic Exploitation of Viral Interference

Viral interference, originally, referred to a state of temporary immunity, is a state whereby infection with a virus limits replication or production of a second infecting virus. However, replication of a second virus could also be dominant over the first virus. In fact, dominance can alternate between the two viruses. Expression of type I interferon genes is many times upregulated in infected epithelial cells. Since the interferon system can control most, if not all, virus infections in the absence of adaptive immunity, it was proposed that viral induction of a nonspecific localized temporary state of immunity may provide a strategy to control viral infections. Clinical observations also support such a theory, which gave credence to the development of superinfection therapy (SIT). SIT is an innovative therapeutic approach where a non-pathogenic virus is used to infect patients harboring a pathogenic virus. For the functional cure of persistent viral infections and for the development of broad- spectrum antivirals against emerging viruses a paradigm shift was recently proposed. Instead of the virus, the therapy should be directed at the host. Such a host-directed-therapy (HDT) strategy could be the activation of endogenous innate immune response via toll-like receptors (TLRs). Superinfection therapy is such a host-directed-therapy, which has been validated in patients infected with two completely different viruses, the hepatitis B (DNA), and hepatitis C (RNA) viruses. SIT exerts post-infection interference via the constant presence of an attenuated non-pathogenic avian double- stranded (ds) RNA viral vector which boosts the endogenous innate (IFN) response. SIT could, therefore, be developed into a biological platform for a new "one drug, multiple bugs" broad-spectrum antiviral treatment approach.

Complete Remission of Vocal Cord Cancer Treated With Low-Dose Ipilimumab Plus Nivolumab Combined With Interleukin-2 and Hyperthermia

We present a 44-year-old male patient, exposed to tobacco smoke and alcohol, with a locally advanced, multiple recurrent squamous cell carcinoma (SCC) of the vocal cord who had undergone resection four times. The patient rejected the mutilating surgery or radiation therapy due to the expected severe lifelong consequences. Instead, the patient opted for complex immunotherapy combining low doses of checkpoint inhibitors ipilimumab-nivolumab (0.3 and 0.5 mg/kg, respectively) with fever-inducing interleukin-2 (IL-2) and hyperthermia, which induced complete remission (CR). Restaging with MRI and laryngoscopy demonstrated lasting remission ongoing now for two years. The fact that this patient is free of any cancer-related signs or symptoms raises the possibility of a long-lasting remission even after the fourth recurrence of a locally advanced squamous cell vocal cord cancer by the induction of therapeutic fever combined with a safe low-dose ipilimumab plus nivolumab therapy to endorse T-cell function.

Low-dose ipilimumab plus nivolumab combined with IL-2 and hyperthermia in cancer patients with advanced disease: exploratory findings of a case series of 131 stage IV cancers - a retrospective study of a single institution

The 3-year overall survival (OS) rate of patients with previously treated or untreated stage III or IV melanoma has by now reached 63% using ipilimumab and nivolumab therapy. However, immune-related adverse events (irAEs) of grade 3 or 4 occurred in 59% of patients leading to discontinuation of therapy in 24.5% of patients and one death. Therapy with checkpoint inhibitors could be safer and more effective in combination with hyperthermia and fever inducing therapies. We conducted a retrospective analysis to test the safety and efficacy of a new combination immune therapy in 131 unselected stage IV solid cancer patients with 23 different histological types of cancer who exhausted all conventional treatments. Treatment consisted of locoregional- and whole-body hyperthermia, individually dose adapted interleukin 2 (IL-2) combined with low-dose ipilimumab (0.3 mg/kg) plus nivolumab (0.5 mg/kg). The objective response rate (ORR) was 31.3%, progression-free survival (PFS) was 10 months, survival probabilities at 6 months was 86.7% (95% CI, 81.0–92.8%), at 9 months was 73.5% (95% CI, 66.2–81.7%), at 12 months was 66.5% (95% CI, 58.6–75.4%), while at 24 months survival was 36.6% (95% CI:28.2%; 47.3%). irAEs of World Health Organization (WHO) Toxicity Scale grade 1, 2, 3, and 4 were observed in 23.66%, 16.03%, 6.11%, and 2.29% of patients, respectively. Our results suggest that the irAEs profile of the combined treatment is safer than that of the established protocols without compromising efficacy.

Significant association between tumor mutational burden and immune-related adverse events during immune checkpoint inhibition therapies

More than 2000 immuno-oncology agents are being tested or are in use as a result of the cancer immunotherapy revolution. Manipulation of co-inhibitory receptors has achieved tumor eradication in a minority of patients, but widespread immune-related adverse events (irAEs) compromised tolerance to healthy self-tissues in the majority. We have proposed that a major mechanism of irAEs is similar to a graft-versus-malignancy effect of graft-versus-host disease. To verify our hypothesis, we retrieved post-marketing data of adverse events from the U.S. Food and Drug Administration Adverse Event Reporting System. A significant positive correlation was revealed in 7677 patients between the reporting odds ratio of irAEs during immune checkpoint inhibitor therapy and the corresponding tumor mutational burden across 19 cancer types. These results can be interpreted to mean that the ICI drugs unleashed T cells against “altered-self,” self, and tumors resulting in better overall survival.

Exploiting autoimmunity unleashed by low-dose immune checkpoint blockade to treat advanced cancer

As a result of the cancer immunotherapy revolution, more than 2000 immuno-oncology agents are currently being tested or are in use to improve responses. Not unexpectedly, the 2018 Nobel Prize in Physiology or Medicine was awarded to James P. Allison and Tasuku Honjo for their development of cancer therapy by the blockade of co-inhibitory signals. Unfortunately, manipulation of the co-inhibitory receptors has also resulted in a safety issue: widespread iatrogenic immune-related adverse events (irAEs). Autoimmunity is emerging as the nemesis of immunotherapy. Originally, it was assumed that CTLA-4 blockade selectively targets T cells relevant to the antitumour immune response. However, an uncontrolled pan T cell activation was induced compromising tolerance to healthy self-tissues. The irAEs are very similar to that of a chronic graft-versus-host-disease (GVHD) reaction following allogeneic bone marrow transplantation (BMT). We hypothesized that ipilimumab induced a graft-versus-malignancy (GVM) effect, which eradicated metastatic melanoma in a minority of patients, but also involved an auto-GVHD reaction that resulted in widespread autoimmunity in the majority. Therefore, we argued for a profound theoretical point against the consensus of experts. The task is not to desperately put the genie back in the bottle by immune-suppressive treatments, but instead to harness the autoimmune forces. In this way, the same goal could be achieved by an antibody as by the adoptive transfer of alloreactive donor lymphocytes, but without severe GVHD. The proof-of-principle of a low-dose-combination immune checkpoint therapy, consisting only of approved drugs and treatments, was demonstrated in 111 stage IV cancer patients.

Complete Clinical Remission of Stage IV Triple-Negative Breast Cancer Lung Metastasis Administering Low-Dose Immune Checkpoint Blockade in Combination With Hyperthermia and Interleukin-2

The prognosis of triple-negative breast cancer with metastases after chemotherapy remains dismal. We report the case of a 50-year-old female with first disease recurrence at the axillary lymph node and, later on, bilateral pulmonary metastases with severe shortness of breath. The patient received low-dose immune checkpoint blockade (concurrent nivolumab and ipilimumab) weekly over 3 weeks with regional hyperthermia 3 times a week, followed by systemic fever-range hyperthermia induced by interleukin-2 for 5 days. She went into complete remission of her pulmonary metastases with transient WHO I-II diarrhea and skin rash. The patient remained alive for 27 months after the start of treatment, with recurrence of metastases as a sternal mass, and up to 3 cm pleural metastases. This exceptional response should instigate further research efforts with this protocol, which consists only of approved drugs and treatments.

Post-infection viral superinfection technology could treat HBV and HCV patients with unmet needs

Background

Viral hepatitis deaths from acute infection, cirrhosis, and liver cancer have risen from the tenth to the seventh leading cause of death worldwide between 1990 and 2013. Even in the oral direct acting antiviral (DAA) agent era there are still large numbers of patients with unmet needs. Medications approved for treatment of chronic hepatitis B virus (HBV) infection do not eradicate HBV often requiring treatment for life associated with risks of adverse reactions, drug resistance, nonadherence, and increased cost. Although DAAs increased virologic cure rates well over 90% in all hepatitis C virus (HCV) genotypes, HCV infection still cannot be cured in a small but significant minority of patients. While most of the medical issues of HCV treatment have been solved, the current costs of DAAs are prohibitive.

Results

The post-infection viral superinfection treatment (SIT) platform technology has been clinically proven to be safe and effective to resolve acute and persistent viral infections in 42 HBV and HCV patients (20 HBV, 22 HCV), and in 4 decompensated patients (2 HBV, 2 HCV). SIT employs a non-pathogenic avian double stranded RNA (dsRNA) virus, a potent activator of antiviral gene responses. Unexpectedly, SIT is active against unrelated DNA (HBV) and RNA (HCV) viruses. SIT does not require lifelong therapy, which is a major advantage considering present HBV treatments. The new viral drug candidate (R903/78) is homogeneously produced by reverse genetics in Vero cells. R903/78 has exceptional pH and temperature stability and also excellent long-term stability; therefore, it can be orally administered, stored and shipped without freezing. Since R903/78 is easy to stockpile, the post-infection SIT could also alleviate the logistic hurdles of surge capacity in vaccine production during viral pandemics.

Conclusion

To help large number of HBV and HCV patients with unmet needs, broad-spectrum antiviral drugs effective against whole classes of viruses are urgently needed. The innovative SIT technological platform will be a great additional armament to conquer viral hepatitis, which is still a major cause of death and disability worldwide.

Anti-CTLA-4 therapy may have mechanisms similar to those occurring in inherited human CTLA4 haploinsufficiency

The inhibitory anti-CTLA-4 antibody, ipilimumab, dramatically improved survival in a subgroup of metastatic melanoma patients. The majority, however, suffered autoimmune-related adverse events (irAEs), sometimes pathognomonic of acute graft-versus-host-disease (GVHD). This implies that the CTLA-4 blockade is not tumor specific. We make a risky but testable prediction: anti-CTLA-4 therapy may have mechanism similar to that occurring in inherited human CTLA-4 haploinsufficiency. If so, a therapeutic paradigm shift is required. The task is not desperately trying to put the genie back in the bottle by immune-suppressive treatments, but harnessing the immense forces liberated by the anti-CTLA-4 antibody blockade by pretargeting or dose adjustment.

Control of minimal residual cancer by low dose ipilimumab activating autologous anti-tumor immunity

In this perspective article, we address the controversy regarding the safety-efficacy issue in ipilimumab trials. While the CTLA-4 blockade interrupted T-cell pathways responsible for immune down-regulation and mediated regression of established malignant tumors in a minority of patients, this has to be weighed against the immune related adverse events (irAEs) suffered by the majority. Based on two groundbreaking but neglected proof-of-principle papers that demonstrated augmented graft-vs.-malignancy (GVM) effect that reversed the relapse of malignancy without worsening the graft-vs.-host disease (GVHD) by a CTLA-4 blockade, here we suggest a therapeutic paradigm shift, which may help break the impasse and resolve this timely issue in oncology.

Outcome of an advanced anaplastic astrocytoma patient treated with Newcastle disease viral (NDV) oncolytic therapy

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Background: Oncolytic viruses are increasingly recognized for their potential promise of lasting impact on our cancer treatment repertoire. The use of attenuated Newcastle Disease Virus (NDV) against cancer was pioneered more than 40 years ago by Laszlo Csatary, a Virginia physician, who died March 20, 2012 at age 88. In 1968, Csatary used attenuated NDV as a cancer treatment. NDV, an RNA virus, shows tumor selectivity in its replication behavior in mammalian cells, including humans. Methods: A.G., a 14-year-old boy, presented in September 1994 with a large left fronto-temporal mass. The tumor was debulked and he then received 56 Gy of radiation to the brain. Pathology indicated the tumor was a glioblastoma multiforme (GBM). By November1995 there was local recurrence. Despite various chemotherapies, the cancer progressed. In May 1996 patient started on attenuated intravenous NDV in Budapest, Hungary. This was the only agent he received for the next 8 years. Results: There was progressive shrinkage of the GBM resulting in complete disappearance at 1 year. The patient remains well with no evidence of tumor 16 years after the start of NDV. Conclusions: NDV was able to eradicate GBM in this seemingly hopeless situation and merits further evaluation in this and other cancers.

Interesting possibilities to improve the safety of ipilimumab

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Background: The problem of the ipilimumab therapy is that a common molecular target (CTLA-4 receptor) is expressed on the targeted and non-targeted T cells, respectively. We suggest that the frequency of immune-related adverse events can be reduced by treating conditions in which the number of the targeted cells is larger than the non-targeted ones and/or by improving the accuracy of the targeting. Methods: The first approach was tested in a phase I clinical trial in patients with relapsed malignancy following allogeneic hematopoietic stem cell transplantation. An ipilimumab blockade was used against CTLA-4 positive allogeneic T cells (responding patients had greater than 80% donor T-cell chimerism). The graft-versus-malignancy (GVM) effects were augmented without a significant impact on graft-versus-host disease (GVHD). A feasible approach could also be pretargeting that has been worked out for radioimmunodetection and radioimmunotherapy. To this end we suggest a testable thought experiment for the treatment of chronic lymphocytic leukemia (CLL). First a streptavidin (StAv) modified anti-CD19 mAb is administered, which is followed by the subsequent delivery of biotin labeled anti-CTLA-4 mAb. The latter endows T cells with the ability to travel to tumor sites without prematurely succumbing to apoptosis, while streptavidin’s ultra-high affinity for biotin (10-15M) ensures a tight bond to the biotin labeled anti-CTLA-4. Results: Using the law of mass action we calculated that above 1 mg/L ipilimumab concentration (i.e. about 5 mg/patient ~70kg) more than 80% of anti-CD19-StAv sensitized B cells will have been bound to anti-CTLA-4-biotin sensitized T cells. Conclusions: This way, the forces of the immune system liberated by the anti-CTLA-4 antibody blockade could be focused with laser sharp accuracy on CLL cells without collateral damage to normal host cells. One should note that 0.3 mg/kg ipilimumab alone already caused mild autoimmunity.

Interesting possibilities to improve the safety and efficacy of ipilimumab (Yervoy)

As predicted, an anti-CTLA-4 mAb (ipilimumab) on binding to T lymphocytes breaks down immune-tolerance. Thereby, it was hoped, tumor-specific-T cells would be freed for a sustained attack on cancer cells. Data on ipilimumab treatment in 1498 patients with advanced melanoma (in 14 phase I-III trials) has shown immune-related adverse events (irAEs) in 64.2% of the patients consistent with tolerance breakdown. However, there is no evidence that the antitumor effects via a CTLA-4 blockade are attributable to T cells specifically targeting tumor cells. In fact, several trials indicate a possible correlation between grade 3 and 4 irAEs with clinical efficacy of ipilimumab; tumor regression may be associated with autoimmunity development. Therefore, we suggest a new treatment paradigm. The non-tumor specific pan-lymphocytic activation should be exploited by a 'pretargeting' approach proven successful in radioimmunodetection and radioimmunotherapy. First, an anti-tumor mAb conjugated with streptavidin (StAv) should be administered to be followed by the delivery of biotin-labeled anti-CTLA-4 mAb. This schedule has the virtue of endowing T cells with the ability to travel to tumor sites without prematurely succumbing to apoptosis, while streptavidin's ultra-high affinity for biotin (K(D), 10⁻¹⁵ M) ensures capturing all T cells binding biotin labeled anti-CTLA-4. Using the law of mass action, we calculated that following administration of ipilimumab at >1 mg/L concentration (∼5 mg per patient ∼70 kgbw), the immense forces of the immune system liberated by the anti-CTLA-4 antibody blockade would then be focused with laser sharp accuracy on tumor cells without collateral damage to normal host cells.

Ipilimumab (Yervoy) and the TGN1412 catastrophe

The development of the anti-CTLA-4 antibody (ipilimumab; marketed as Yervoy) immune regulatory therapy was based on the premise that "Abrogation of the function of CTLA-4 would permit CD28 to function unopposed and might swing the balance in favor of immune stimulation, tolerance breakdown and tumor eradication…" (Weber, 2009). By now, the vast majority of data collected from more than 4000 patients proves that this prediction was entirely correct. Paradoxically, the successful blockade of immune checkpoints raises the question whether an anti-CTLA-4 antibody could ever become an important therapy against cancer. T cells lost their ability to discriminate between self and non-self. Thus, tolerance to self tissues was broken in ∼70% of the patients. In the recent industry-sponsored phase III clinical trial of ipilimumab, 147 (38.7%) of the patients experienced severe adverse events and 6.8% suffered dose-limiting events (8.4%, in the ipilimumab-alone group). There were 14 deaths related to the study drugs and 7 of these were associated with immune-related adverse events. In contrast, the complete response rate was only 0.2%, in one patient out of 403 who received ipilimumab plus a peptide vaccine. Promoters of ipilimumab appear to be unmindful of the clinical trial catastrophe in London. Then, a humanized "superagonist" anti-CD28 monoclonal antibody, TGN1412, which "preferentially" activated regulatory T cells, at a higher dose, also activated all CD28 positive T cells. This precipitated a "cytokine storm" leading to life-threatening multiple organ failure in the six healthy human volunteers. Neither anti-CD28 nor anti-CTLA-4 therapies rely on antigen-specificity. Both release free antibody into the body against common molecular targets that are expressed on the targeted as well as on the non-targeted T cells. At lower antibody doses specific T cells are preferentially activated. With increasing antibody dose, however, the kinetics of the interaction is pushed in favor of widespread non-specific T cell expansion. Using the law of mass action we calculated that the vast majority of the CTLA-4 receptors on all activated T cells (including melanoma specific T cells) in the phase III clinical trial of ipilimumab will have been saturated. This would explain the runaway immune response observed. The conclusions drawn by the authors of the ipilimumab trial paper could bear an independent inspection and reassessment concerning the validation of the blockade of immune checkpoints as an important therapeutic strategy against cancer.

Beneficial treatment of patients with advanced cancer using a Newcastle disease virus vaccine (MTH-68/H)

Newcastle Disease Virus Vaccine (MTH-68/H) was administered to patients suffering from advanced neoplastic diseases after non-efficient tumor-destructive treatment. Case reports of selected patients suggest promising effects of this treatment. A prospectively-randomized clinical study (phase III; in accordance with Good Clinical Practice, GCP) was proposed to confirm these results and is currently under consideration.

Inhibition of the classical activation pathway of complement-mediated lysis by monoclonal antibodies to complement components C3c and C3d

Eight epitope-mapped monoclonal antibodies (MoAbs) to complement component C3d and five to complement component C3c were investigated to determine whether they could inhibit the classical activation pathway of complement-mediated lysis (CML) by using blood group AB red cells sensitized by A or B MoAbs. Three IgM C3d MoAbs and one IgG1 C3c MoAb were able to inhibit CML in a dose-dependent manner. In the presence of excess complement, no inhibition was observed. The greatest inhibition was observed with two high-affinity IgM antibodies that were specific for epitope 1 on the C3d component. Some inhibition was observed with a high-affinity IgM antibody specific for epitope 3 of the C3d component and also with a lower-affinity IgG antibody specific for epitope 1 of the C3c component. The results indicate that some complement MoAbs have the capacity to distinguish between conformationally and/or functionally different forms of red cell-bound C3.

EBV-related cytotoxicity of Fc receptor negative T lymphocytes separated from the blood of infectious mononucleosis patients

Epstein-Barr virus (EBV) related specific killing was demonstrated previously in the T cell enriched subpopulations of blood lymphocytes of IM patients. In the present work we demonstrate that the cytotoxic cells belong to the Fc negative T subset. T cells in the blood of IM patients can be divided in 2 categories, 1 Fc positive with non discriminative cytotoxicity and the other, Fc negative with selective cytotoxicity against EBV genome carrying lymphoblastoid cell lines.

Search for disease-related cytotoxicity in mammary tumor patients

Blood lymphocytes from benign and malignant mammary tumor patients ahd healthy blood donors were tested for cytotoxicity against monolayer cell lines, including two which were derived from breast carcinomas. Generally, the T subset was not cytotoxic, and if so this was not restricted to the relevant cell lines. In accordance with previous results 'null' cells were most efficient in the seemingly non-selective cytotoxicity.