Ibrutinib does not impact CCR7-mediated homeostatic migration in T-cells from chronic lymphocytic leukemia patients

Bruton’s tyrosine kinase inhibitor ibrutinib has significantly changed treatment landscape in chronic lymphocytic leukemia (CLL). Growing evidence supports ibrutinib to work beyond the effect on tumor cells by means of, for example, restoring functionality of the T-cell compartment and increasing circulating T-cell numbers. Recent evidence suggests T-cell enhanced expansion, rather than increased egress from secondary lymphoid organs (SLO), as a root cause for ibrutinib-induced lymphocytosis. However, whether the latter physiological change is also a consequence of a forced retention in blood remains undisclosed. Since CCR7 is the main chemokine receptor taking over the homing of T-cells from peripheral compartments to lymph nodes and other SLO, we aimed to investigate the impact of ibrutinib on CCR7 functionality in T-cells. To this end, we documented receptor expression in T-cells from a large cohort of ibrutinib-treated CLL patients, and performed different in vivo and in vitro migration models. Overall, our data confirm that CCR7 expression or receptor-mediated migration in CLL T-cells is not affected by ibrutinib. Furthermore, it does not modulate CCR7-driven homing nor nodal interstitial migration. Together, our results support that ibrutinib-induced CLL T-cell accumulation in the blood stream is not derived from an impairment of CCR7-driven recirculation between the SLO and bloodstream, and therefore T-cell expansion is the most plausible causeA.M.-J. was partially financed by Alfonso Martín Escudero Foundation. The other authors received no grants for this wor

CCR7 as a novel therapeutic target in t-cell PROLYMPHOCYTIC leukemia

T-cell prolymphocytic leukemia (T-PLL) is a poor prognostic disease with very limited options of efficient therapies. Most patients are refractory to chemotherapies and despite high response rates after alemtuzumab, virtually all patients relapse. Therefore, there is an unmet medical need for novel therapies in T-PLL. As the chemokine receptor CCR7 is a molecule expressed in a wide range of malignancies and relevant in many tumor processes, the present study addressed the biologic role of this receptor in T-PLL. Furthermore, we elucidated the mechanisms of action mediated by an anti-CCR7 monoclonal antibody (mAb) and evaluated whether its anti-tumor activity would warrant development towards clinical applications in T-PLL. Our results demonstrate that CCR7 is a prognostic biomarker for overall survival in T-PLL patients and a functional receptor involved in the migration, invasion, and survival of leukemic cells. Targeting CCR7 with a mAb inhibited ligand-mediated signaling pathways and induced tumor cell killing in primary samples. In addition, directing antibodies against CCR7 was highly effective in T-cell leukemia xenograft models. Together, these findings make CCR7 an attractive molecule for novel mAb-based therapeutic applications in T-PLL, a disease where recent drug screen efforts and studies addressing new compounds have focused on chemotherapy or small molecules.Peer reviewe

Deregulated cellular circuits driving immunoglobulins and complement consumption associate with the severity of COVID-19 patients

SARS-CoV-2 infection causes an abrupt response by the host immune system, which is largely responsible for the outcome of COVID-19. We investigated whether the specific immune responses in the peripheral blood of 276 patients were associated with the severity and progression of COVID-19. At admission, dramatic lymphopenia of T, B, and NK cells is associated with severity. Conversely, the proportion of B cells, plasmablasts, circulating follicular helper T cells (cTfh) and CD56–CD16+ NK-cells increased. Regarding humoral immunity, levels of IgM, IgA, and IgG were unaffected, but when degrees of severity were considered, IgG was lower in severe patients. Compared to healthy donors, complement C3 and C4 protein levels were higher in mild and moderate, but not in severe patients, while the activation peptide of C5 (C5a) increased from the admission in every patient, regardless of their severity. Moreover, total IgG, the IgG1 and IgG3 isotypes, and C4 decreased from day 0 to day 10 in patients who were hospitalized for more than two weeks, but not in patients who were discharged earlier. Our study provides important clues to understand the immune response observed in COVID-19 patients, associating severity with an imbalanced humoral response, and identifying new targets for therapeutic interventionThe study was funded by grants SAF2017- 82886-R to FS-M from the Ministerio de Economía y Competitividad, and from “La Caixa Banking Foundation” (HR17-00016) to FS-M. Grant PI018/01163 to CMC and grant PI19/00549 to AA were funded by Fondo de Investigaciones Sanitarias, Ministerio de Sanidad y Consumo, Spain. SAF2017-82886-R, PI018/01163 and PI19/00549 grants were also co-funded by European Regional Development Fund, ERDF/FEDER. This work has been funded by grants Fondo Supera COVID (CRUE-Banco de Santander) to FSM, and “Ayuda Covid 2019” from Comunidad de Madri

Caracterización del efecto de ibrutinib en la expresión y funcionalidad del receptor CCR7 en leucemia linfocítica crónica y en la actividad antitumoral de CAP-100, el primer anticuerpo terapéutico contra CCR7

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Bioquímica. Fecha de Lectura: 15-07-2022Esta tesis tiene embargado el acceso al texto completo hasta el 15-01-2024El tratamiento de la leucemia linfocítica crónica (LLC) está dominado en la actualidad por el uso de ibrutinib, el primer inhibidor de la tirosina quinasa de Bruton (BTKi). Sin embargo, el número de pacientes que recaen o no responden a ibrutinib es cada vez mayor y se hacen necesarias dianas y estrategias terapéuticas alternativas. CAP-100 es un anticuerpo terapéutico nuevo dirigido contra el receptor de quimiocinas homeostático CCR7, que se encuentra sobreexpresado en las células leucémicas de LLC-B, dirigiéndolas a ganglio linfático (GL) y participando de manera fundamental en la biología de la enfermedad. Estudios previos realizados en un número limitado de muestras sugerían que ibrutinib inducía la pérdida de expresión de CCR7 en la superficie de las células de LLC-B, sin profundizar en aspectos funcionales. Dado que CAP-100 será evaluado en ensayos clínicos en pacientes que habrán recibido ibrutinib como terapia previa, como primer objetivo quisimos investigar en una cohorte mucho mayor el impacto del inhibidor en la expresión y funcionalidad de CCR7, así como en la actividad terapéutica de CAP-100. Por otro lado, aunque es sabido que ibrutinib induce linfocitosis T en pacientes de LLC, los mecanismos subyacentes han sido sólo parcialmente descritos a nivel de la salida de linfocitos T (LT) de órganos linfoides secundarios (OLS) a sangre periférica (SP). Dado que la linfocitosis puede ser debida también a un efecto en la entrada desde SP a GL, como segundo objetivo nos propusimos estudiar el impacto de ibrutinib en la homeostasis T mediada por CCR7. Nuestros datos confirman que ibrutinib promueve una moderada disminución de la expresión de CCR7 en la superficie de las células de LLC-B, aunque no tiene aparentemente un efecto en la migración quimiotáctica mediada por CCR7. Además, las células de LLC-B mantienen niveles de expresión de CCR7 apropiados para la terapia con CAP-100, que demostró una completa inhibición de la migración inducida por CCR7 y una potente citotoxicidad, tanto en pacientes en tratamiento con ibrutinib como en aquellos refractarios. Por otro lado, ibrutinib no modula la expresión de CCR7 en LT ni afecta a la quimiotaxis guiada por el receptor, la migración intersticial o la entrada a GL, descartando así que la linfocitosis T sea ocasionada por un efecto en el eje CCR7 y/o una entrada alterada a GL. En resumen, nuestros resultados descartan el eje CCR7 como diana relevante en el efecto terapéutico de ibrutinib y validan CAP-100 como alternativa para pacientes en tratamiento actual o en recaída con ibrutinib. Así mismo, confirman que CAP-100 e ibrutinib tienen mecanismos de acción complementarios, no solapantes, que apoyan una terapia combinada donde CAP-100 prevendría el acceso de las células de LLC-B a los nichos de los G

Ibrutinib Does Not Impact CCR7-Mediated Homeostatic Migration in T-Cells from Chronic Lymphocytic Leukemia Patients

Bruton’s tyrosine kinase inhibitor ibrutinib has significantly changed treatment landscape in chronic lymphocytic leukemia (CLL). Growing evidence supports ibrutinib to work beyond the effect on tumor cells by means of, for example, restoring functionality of the T-cell compartment and increasing circulating T-cell numbers. Recent evidence suggests T-cell enhanced expansion, rather than increased egress from secondary lymphoid organs (SLO), as a root cause for ibrutinib-induced lymphocytosis. However, whether the latter physiological change is also a consequence of a forced retention in blood remains undisclosed. Since CCR7 is the main chemokine receptor taking over the homing of T-cells from peripheral compartments to lymph nodes and other SLO, we aimed to investigate the impact of ibrutinib on CCR7 functionality in T-cells. To this end, we documented receptor expression in T-cells from a large cohort of ibrutinib-treated CLL patients, and performed different in vivo and in vitro migration models. Overall, our data confirm that CCR7 expression or receptor-mediated migration in CLL T-cells is not affected by ibrutinib. Furthermore, it does not modulate CCR7-driven homing nor nodal interstitial migration. Together, our results support that ibrutinib-induced CLL T-cell accumulation in the blood stream is not derived from an impairment of CCR7-driven recirculation between the SLO and bloodstream, and therefore T-cell expansion is the most plausible cause