CD4, ichorbio, ICH1042

Our team has carried out deep research in the published scientific literature to identify papers and reports using ICH1042 and followed up by extraction and validation of the available data to assess its performance according to pAbmAbs rating criteria.
ICH1042 (GK1.5) is a low-endotoxin rat monoclonal anti-mouse CD4 produced by ichorbio. The antibody is most often used as a blocking/depleting reagent in vivo or in functional assays. In the literature (e.g., Cao et al., J Nanobiotechnology 2023), it was applied as a blocking antibody against CD4+ T cells and shown to be effective in that context. Manufacturer QC data support purity and low endotoxin, but there is limited independent validation of this exact product across multiple applications.
The Cao et al. paper mentions ICH1042 only in the Methods list (used as a blocking antibody) and does not provide lot numbers, dilution, titration curves, representative gating plots showing blocking efficiency, or knockout/negative tissue controls that would demonstrate high-confidence specificity in multiple applications.
We did not find a broad set of independent peer-reviewed papers that publish detailed antibody validation (dilution series, western blots showing single band, KO/knockdown controls, or comparative staining panels) specifically for the ichorbio ICH1042 product beyond its use as a blocking reagent in Cao et al.
The clone GK1.5 itself (GK1.5 anti-CD4) is a widely used clone (sold by multiple vendors) and has a long history as a CD4 depleting/blocking reagent in mice.
In summary, our four star rating is strongly influenced by clone history repeatedly showing functional CD4+ T-cell blockade. Works as expected, but additional independent studies with ichorbio’s formulation would strengthen confidence. We therefore highly encourage other scientists to share their observations.