Large negative lymph nodes - a surrogate for immune activation in rectal cancer patients?

AIM: The size of regional, tumor draining lymph nodes without metastasis (LNneg) found in rectal cancer resection specimens varies and seems to be related to patient survival. Yet, the histopathological features influencing LNneg size in rectal cancer have not been studied in detail. Our pilot study focused on investigating the relationship between lymph node (LN) size and LNneg microarchitecture in rectal cancer (RC) resection specimens. METHOD: In this retrospective cohort study, resection specimens from 146 RC patients, treated with either surgery alone (n = 29) or neoadjuvant therapy followed by resection (n = 117), were included in the study. Histology of LNnegs was reviewed to establish number of lymphoid follicles and presence of intranodal fat. Longest long axis and area of each LN were measured digitally. RESULTS: 1830 LNnegs were measured. The microarchitecture was analyzed in a subset of 680 LNnegs. 153 (22.5 %) LNnegs contained intranodal fat. After neoadjuvant treatment, presence of intranodal fat was related to smaller LNneg area (median (range) area of LNneg without intranodal fat: 4.51 mm2 (0.15-46.89 mm2), with intranodal fat: 3.46 mm2 (0.12-27.22 mm2), p = 0.048). A higher number of lymphoid follicles was related to a larger LNneg area in both patient groups (p < 0.001). CONCLUSION: Our pilot data suggest that in rectal cancer the presence of large regional LNnegs may reflect increased immune activation due to tumor related antigens. Further studies are warranted to investigate whether histologically visible microarchitectural features of LNnegs such as lymphoid follicles translate to particular features in radiological images and hence could potentially help to identify LNneg with more certainty at the time of pre-treatment disease staging.

Inactivation of lipid enveloped viruses by octanoic Acid treatment of immunoglobulin solution.

Inactivation of lipid enveloped viruses by treatment with octanoic acid has been investigated for three intravenous immunoglobulin preparations, using Human Immunodeficiency Virus, Bovine Viral Diarrhoea Virus, Sindbis Virus and Pseudorabies Virus as test viruses. At a concentration of 7.45 g octanoic acid per kg solution complete inactivation of lipid enveloped viruses to below detectable level (>5.36, >4.68, >6.25 and >5.55 log(10), respectively) was achieved within the first minutes of treatment. Octanoic acid treatment as described here, has been demonstrated as an effective and rapid virus inactivation procedure, which shows high robustness at the tested ranges of temperature, pH and protein content of the test material. However, pH must be considered as a critical parameter of treatment, as octanoic acid fails to inactivate lipid coated viruses at basic pH. At suitable conditions, e.g. pH<6.0 and a concentration of >3.7 g/kg, octanoic acid treatment gives reliable and highly effective inactivation of lipid enveloped viruses.

Anti-CD16/CD30 bispecific antibody treatment for Hodgkin's disease: role of infusion schedule and costimulation with cytokines.

The natural killer cell-activating anti-CD16/CD30 bispecific monoclonal antibody (BiMAb) had shown efficacy in a Phase I/II trial of refractory Hodgkin's disease (HD). To gain additional information on clinical efficacy and to investigate the effects of different application schedules and the concomitant application of cytokines, we performed a second randomized pilot trial using this BiMAb in patients with refractory HD. Patients received 4 x 25 mg HRS-3/A9 either as a continuous infusion for 4 days or as a 1-h infusion every other day. In case of an objective response, retreatment was attempted after 4 weeks; in case of stable disease (SD), a second course was given after prestimulation with interleukin 2 and followed by granulocyte macrophage colony-stimulating factor s.c. A total of 16 heavily pretreated patients received one to four BiMAb courses. Overall, we observed one complete remission and three partial remissions lasting 5-9 months (three of four of these responses occurred after continuous BiMAb infusion) and four cases of SD for 3 to >6 months. Interleukin 2 pretreatment before the second BiMAb course resulted in a significant increase of circulating natural killer cells in all five patients treated. This coincided with the conversion of two cases of SD into one complete remission and one partial remission. HRS-3/A9-related side effects consisted of mild fever in only six patients. In summary, this second trial confirmed the antitumor efficacy of this BiMAb against HD and the minor toxicity of this BiMAb. Coadministration of cytokines might contribute to an augmented antitumor activity, and additional clinical trials are warranted to optimize this novel treatment modality.

Treatment of refractory Hodgkin's disease with an anti-CD16/CD30 bispecific antibody.

Fifteen patients with refractory Hodgkin's disease were treated in a phase I/II trial with the natural killer (NK)-cell-activating bispecific monoclonal antibody HRS-3/A9, which is directed against the Fc(gamma)-receptor III (CD16 antigen) and the Hodgkin's-associated CD30 antigen, respectively. Median counts of NK cells and of all lymphocyte subsets were considerably decreased in the patients before therapy. HRS-3/A9 was administered 4 times every 3 to 4 days, starting with 1 mg/m2. The treatment was well tolerated, and the maximum tolerated dose was not reached at 64 mg/m2, the highest dose administered because of the limited amounts of HRS-3/A9 available. Side effects were rare and consisted of fever, pain in involved lymph nodes, and a maculopapulous rash. A total of 9 patients developed human antimouse Ig antibodies, and 4 patients developed an allergic reaction after attempted retreatment. A total of 1 complete and 1 partial remission (lasting 6 and 3 months, respectively) [corrected], 3 minor responses (1 to 11+ months), and 1 mixed response were achieved. There was no clear-cut dose-side effect or dose-response correlation. Our results encourage further clinical trials with this novel immunotherapeutic approach and emphasize the necessity to reduce the immunogenicity of the murine bispecific antibodies.

Improvement of virus safety of a S/D-treated factor VIII concentrate by additional dry heat treatment at 100 degrees C.

In order to increase the virus safety of a solvent/detergent-treated Factor VIII concentrate in regard to non-lipid coated viruses and to respond to the continuous discussion about reports on hepatitis A transmission by Factor VIII preparations, we have investigated the effect of a terminal dry heat treatment (30 min 100 degrees C) on HAV and various other viruses. By this treatment Hepatitis A virus was inactivated below detectable level after a few minutes (> 5.3 log10). Other RNA viruses such as the Human Immunodeficiency Virus (> 6.6 log10), bovine viral diarrhoea virus (> 6.6 log10) and vesicular stomatitis virus (> 5.8 log10) were also inactivated below detectable level. Pseudo rabies virus and reovirus Type 3 are inactivated by 5.7 and > 6.0 log10, respectively. SV40 and bovine parvo virus showed significant resistance to dry heat treatment. We conclude that the involvement of two strong virus inactivation steps, acting by different mechanisms, improves the virus safety of Factor VIII concentrates without destroying the Factor VIII activity. Moreover, the terminal 100 degrees C heat treatment for 30 min represents an effective measure to inactivate non-lipid enveloped viruses, in particular hepatitis A, which is resistant to solvent/detergent treatment.