Does PRRT with standard activities of 177Lu-octreotate really achieve relevant somatostatin receptor saturation in target tumor lesions?: insights from intra-therapeutic receptor imaging in patients with metastatic gastroenteropancreatic neuroendocrine tumors

Twenty plantain crop fields were sampled to identify Meloidogyne spp. in Tierralta and Valencia municipalities. Ten soil and root samples per field were taken to obtain the nematodes. Meloidogyne species classification was based on the perineal pattern of the female, shape of the stylet in females, males and juveniles (J2), and shape and number of rings on the cephalic region in J2 and males. Stylet length and dorsal oesophageal gland (DOG) on males, females and J2, body length, tail and hyaline tail region in J2 were measured to identify the specie of root-knot nematode. Meloidogyne spp. were found in 80% of the fields in Valencia, and 60% of the field in Tierralta. M. incognita and M. arenaria were detected. M. incognita was the most frequent species throughout the sampled area. Mixtures of both species were found in both municipalities. This is the first report of mixed M. incognita and M. arenaria associated to plantain crop in Colombia.Veinte cultivos de plátano fueron muestreados en los municipios de Tierralta y Valencia para identificar las especies de Meloidogyne asociadas a este cultivo. Diez muestras de suelos y raíces fueron colectadas en cada de los lotes, las cuales fueron usadas para la obtención de los nemátodos. La clasificación de las especies se basó en las características morfológicas (patrón perineal de las hembras, forma del estilete de hembras, machos y juveniles (J2); forma y número de anillos de la región cefálica de J2 y machos) y morfométricas (longitud del estilete y la distancia de la base del estilete a la desembocadura de la glándula dorsal (D.G.O) de hembras, machos y J2; longitud del cuerpo, la cola y la región hialina de los J2. En el 80% de las fincas en Valencia se detectó la presencia de estos nematodos, mientras que el 60% de los predios en Tierralta fueron positivos para los mismos. Las especies encontradas fueron Meloidogyne incognita y M. arenaria. De estas, M. incognita fue la más frecuente detectada en la zona productora de plátano en los dos municipios. Mezcla de especies fueron detectadas en ambos municipios. Se reporta por primera vez en Colombia las especies M. incognita y M. arenaria, así como la mezcla de las mismas asociadas al cultivo de plátano

An IL12-IL2-antibody fusion protein targeting Hodgkin's lymphoma cells potentiates activation of NK and T cells for an anti-tumor attack.

Successful immunotherapy of Hodgkin's disease is so far hampered by the striking unresponsiveness of lymphoma infiltrating immune cells. To mobilize both adoptive and innate immune cells for an anti-tumor attack we fused the pro-inflammatory cytokines IL2 and IL12 to an anti-CD30 scFv antibody in a dual cytokine fusion protein to accumulate both cytokines at the malignant CD30(+) Hodgkin/Reed-Sternberg cells in the lymphoma lesion. The tumor-targeted IL12-IL2 fusion protein was superior in activating resting T cells to amplify and secrete pro-inflammatory cytokines compared to targeted IL2 or IL12 alone. NK cells were also activated by the dual cytokine protein to secrete IFN-γ and to lyse target cells. The tumor-targeted IL12-IL2, when applied by i.v. injection to immune-competent mice with established antigen-positive tumors, accumulated at the tumor site and induced tumor regression. Data demonstrate that simultaneous targeting of two cytokines in a spatial and temporal simultaneous fashion to pre-defined tissues is feasible by a dual-cytokine antibody fusion protein. In the case of IL12 and IL2, this produced superior anti-tumor efficacy implying the strategy to muster a broader immune cell response in the combat against cancer

Figure 4. Biodistribution of HRS3-scFv-IL12 and HRS3-scFv-Fc-IL12 fusion proteins.

<p>HRS3-scFv-IL12 and HRS3-scFv-Fc-IL12 fusion proteins were purified and labeled with ¹³¹I as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044482#s4" target="_blank">Materials and Methods</a>. SCID mice were s.c. transplanted with CD30⁺ L540cy Hodgkin's lymphoma cells (2×10⁷/animal) and animals with established tumors (>0.5 cm³) were intravenously injected with ¹³¹I -labeled fusion proteins. Animals were sacrificed after 24 h, 48 h and 72 h (HRS3-scFv-IL12: 4 mice/group; HRS3-scFv-Fc-IL12: 3 mice/group), respectively, organs were recovered and tissue retention of radioactivity (%) was determined as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044482#s4" target="_blank">Materials and Methods</a>.</p

Response and long-term control of bone metastases after peptide receptor radionuclide therapy with (177)Lu-octreotate

Peptide receptor radionuclide therapy (PRRT) is an efficient treatment for gastroenteropancreatic neuroendocrine tumors (GEP NETs), with outstanding overall response rates and survival. However, little is known about the particular efficacy regarding bone metastasis (BM)

Biodistribution of HRS3-scFv-IL12 fusion protein.

1<p>Values represent the mean percentage of injected dose per g tissue (n = 4 mice).</p><p>doi:10.1371/journal.pone.0044482.t001</p

Figure 3. Antigen-specific binding of antibody targeted IL-2 and IL12 fusion proteins.

<p>(A) Equimolar amounts of the scFv-Fc fusion proteins were incubated in serial dilutions in micro-titer plates coated with the anti-idiotypic mAb 9G10 which binds to the HRS3 scFv antibody targeting domain of the fusion proteins. For control, same amounts of human IgG1 were added. Bound fusion proteins were detected by an anti-IgG1 antibody directed towards the Fc spacer domain. A representative experiment out of three is shown. (B) CD30⁺ L540cy Hodgkin's lymphoma cells were incubated with serial dilutions of the anti-CD30-Fc fusion proteins or of IgG1 for control. Bound proteins were detected by a PE-conjugated F(ab)₂ goat anti-human IgG1 antibody. Cells were analyzed by flow cytometry and the mean fluorescence intensity (MFI) was determined. A representative experiment out of three is shown. (C) Equimolar amounts of purified HRS3-scFv-IL12 and HRS3-scFv-Fc-IL12 fusion proteins, respectively, or (D) of HRS3-scFv-IL2 and HRS3-scFv-Fc-IL2 fusion proteins, respectively, were incubated in CD30 coated microtiter plates in the presence of increasing amounts of soluble CD30. Bound proteins were detected by biotinylated anti-IL12 (C) or anti-IL2 (D) antibodies and streptavidin-conjugated POD. Binding inhibition was determined as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044482#s4" target="_blank">Materials and Methods</a>. An experiment out of two with similar results is shown.</p