Effective, Long-Term, Neutrophil Depletion Using a Murinized Anti-Ly-6G 1A8 Antibody

Abstract

Neutrophils are crucial innate immune cells but also play key roles in various diseases, such as cancer, where they can perform both pro- and anti-tumorigenic functions. To study the function of neutrophils in vivo, these cells are often depleted using Ly-6G or Gr-1 depleting antibodies or genetic “knockout” models. However, these methods have several limitations, being only partially effective, effective for a short term, and lacking specificity or the ability to conditionally deplete neutrophils. Here, we describe the use of a novel murinized Ly-6G (1A8) antibody. The murinized Ly-6G antibody is of the mouse IgG2a isotype, which is the only isotype that can bind all murine Fcγ receptors and C1q and is, therefore, able to activate antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent phagocytosis (ADCP) and complement-dependent cytotoxicity (CDC) pathways. We show that this mouse-Ly-6G antibody shows efficient, long-term, and near-complete (>90%) neutrophil depletion in the peripheral blood of C57Bl6/J, Balb/c, NXG and SCID mice for up to at least four weeks, using a standardized neutrophil depletion strategy. In addition, we show that neutrophils are efficiently depleted in the blood and tumor tissue of IMR32 tumor-bearing SCID mice, analyzed six weeks after the start of the treatment.

VapC12 ribonuclease toxin modulates host immune response during Mycobacterium tuberculosis infection

“…As neutrophils are an abundant component of the innate immune system, their highly inflammatory actions have potentially severe consequences for host tissues ( 43 ). When the regulatory mechanisms responsible for clearing apoptotic neutrophils are compromised or if the underlying infection cannot be resolved, the actions of neutrophils may turn detrimental to the host ( 44 , 45 ). As previously reported, neutrophils depletion can be achieved by the administration of 1A8 antibody ( 45 ).…”

“…When the regulatory mechanisms responsible for clearing apoptotic neutrophils are compromised or if the underlying infection cannot be resolved, the actions of neutrophils may turn detrimental to the host ( 44 , 45 ). As previously reported, neutrophils depletion can be achieved by the administration of 1A8 antibody ( 45 ). To confirm the role of neutrophils in ▵ vapC12 induced hypervirulent phenotype we infected groups of C57BL/6 mice, with either 1A8 antibody or their isotype control ( Figure 6A ).…”

β-Lapachone promotes the recruitment and polarization of tumor-associated neutrophils (TANs) toward an antitumor (N1) phenotype in NQO1-positive cancers

“… 43 , 44 Furthermore, blockade of Ly6G using a neutralizing antibody (clone 1A8) treatment has been found to decrease neutrophil tissue infiltration and impair their response to injury. 45 , 46 To assess the antitumor activity of β-Lap under conditions of neutrophil deficiency, we used an anti-Ly6G antibody to deplete neutrophils in C57BL/6 WT mice bearing subcutaneous MC38, TC-1 and EO771 tumors, as well as in BALB/c WT mice bearing 4T1 tumors. Mice were treated with a vehicle (20% HPβCD), β-Lap, anti-Ly6G antibody (clone 1A8), or a combination of β-Lap and anti-Ly6G antibody every other day for a total of four treatments, and tumor volume was measured to evaluate the antitumor activity.…”

Enhancing IgA-mediated neutrophil cytotoxicity against neuroblastoma by CD47 blockade

“…http://jitc.bmj.com/ Open access intraperitoneally three times a week at a dose of 100 µg per mouse. 40 Treatment was started from day 4 and was given intraperitoneally. IgG ch14.18 was administered once a week at a dosage of 5 mg/kg, IgA ch14.18 three times a week at 25 mg/kg.…”