A new chimeric recombinant antibody for improved neutrophil depletion in vivo
Understanding neutrophil behavior is central to advancing research in infection, inflammation, and cancer. As first responders in the immune system, neutrophils play a pivotal role in disease progression. However, studying them in live models has long been limited by the challenge of depleting them effectively without affecting other immune cells or animal welfare.
This challenge inspired a collaboration between Dr. Emilie Stolarczyk, Scientific Lead for Immunology and Infectious Diseases at Abcam, and Dr. Tatyana Chtanova, Head of the Tumour Immunology Laboratory at UNSW Sydney and the Garvan Institute. Combining expertise in antibody engineering and in vivo immune cell dynamics, they developed a refined tool: a chimeric recombinant anti-Ly6G antibody for targeted neutrophil depletion.
Why neutrophil depletion matters
Neutrophils influence everything from wound healing to tumor progression. To study their function, researchers often use antibodies targeting Ly6G, a surface marker specific to neutrophils. The commonly used rat IgG2a anti-Ly6G [1A8] antibody, despite its specificity, has a short half-life in mice, requiring frequent dosing and raising concerns about animal stress and data variability.
A smarter solution: Murinized chimeric antibodies
To overcome these limitations, the team engineered murinized versions of the anti-Ly6G [1A8] clone – mouse IgG2a and IgG2c – to improve compatibility with mouse immune systems. These versions reduce anti-rat immune responses and extend the duration of neutrophil depletion.
The mouse IgG2c anti-Ly6G [1A8]stands out for its sustained performance in C57BL/6 mice, a common strain in immunology research.
What the data shows
In comparative studies using BigRed/CatchupIVM-red mice, the mouse IgG2c anti-Ly6G antibody outperformed both the rat IgG2a anti-Ly6G and anti-Gr-1 (targeting monocytes, neutrophils, and subsets of macrophages) antibodies. Neutrophil depletion remained robust 48 hours post-injection, while the rat antibody showed early rebound. Notably, residual neutrophils in the IgG2c group had lower Ly6G expression, indicating they were newly generated, offering researchers deeper insight into neutrophil turnover.
Benefits for researchers and animal welfare
This new antibody reduces the need for frequent injections, minimizing animal stress and improving experimental consistency. It also enables longer-term studies in chronic inflammation, cancer, and infection models – making it a valuable addition to the immunologist’s toolkit.
Designed for flexibility
With both IgG2a and IgG2c formats available, researchers can select the version best suited to their mouse strain, ensuring optimal performance and minimizing immune interference.
A tool for modern immunology
The mouse IgG2c anti-Ly6G [1A8] is more than an upgrade – it’s a thoughtfully engineered solution that supports better science and better animal care. By enabling sustained, specific neutrophil depletion, it empowers researchers to explore immune dynamics with greater precision and confidence.
Related resources
References
1. Stackowicz, J., Jönsson, F. & Reber, L.L. Mouse models and tools for the in vivo study of neutrophils. Front. Immunol. 10, 3130 (2020).
2. Fleming, T.J., Fleming, M.L. & Malek, T.R. Selective expression of Ly-6G on myeloid lineage cells in mouse bone marrow. J. Immunol. 151, 2399–2408 (1993).
3. Yam, A.O. et al. Neutrophil conversion to a tumor-killing phenotype underpins effective microbial therapy. Cancer Res. 83, 1315–1328 (2023).
4. Deniset, J.F. et al. Splenic Ly6G^high^ mature and Ly6G^int^ immature neutrophils contribute to eradication of S. pneumoniae. J. Exp. Med. 214, 1333–1350 (2017).