What specifications and prices are available for in-stock tumor tissue microarrays covering multiple cancer types?

The common specifications of spot multi-cancer chips are 48, 60, 80, 100 cases, etc., the dot diameter is 1.0/1 .5/2.0 mm, and the repetition points are mostly duplicate or triplicate. The new antibody IHC validation recommends a model with a repeat point of 2.0 mm to avoid false negatives due to tumor heterogeneity. The price cannot be given a fixed number. Generally, the unit price of a single sheet of small specifications is high, and the whole box or multiple sheets will be low. You need to inquire according to the number of cases, point diameter, repeat points, and whether there is cancer. Arrival in stock usually takes 3-7 business days and often includes detachable tablets.

When selecting a model, don't just look at the number of cases. First obtain the dot array image and annotations to confirm whether it includes the subtypes you care about: for lung cancer, distinguish adenocarcinoma from squamous cell carcinoma; for breast cancer, there are different grades or molecular subtypes; for colorectal cancer, focus on stage and degree of differentiation. Models with paired adjacent normal or normal controls are more suitable for evaluating antibody specificity, and the normal spots should preferably be immediately adjacent to the tumor spots to facilitate signal comparison in the same field of view. Request the HE staining and fixation conditions for that catalog number to confirm the integrity of the tissue microarray spots.

It is recommended to first purchase 1-2 small-sized products for pilot experiments, but antigen retrieval, antibody dilution, and chromogenic development time should be kept constant. Upon arrival, first check for cracks, tissue detachment, or wrinkles; if needed, bake the slides at 60°C before staining. Even with the same catalog number, different lots may show background differences due to wax block aging or varying storage conditions. Do not directly apply the absolute H-score from the pilot experiment to the large sample; negative/positive controls should be re-established in the large sample.

After the small specification pre-test, the large specification can be supplemented, and the batch consistency cannot be verbally confirmed. This can be done: the supplier is required to lock the source of the same donor wax block, or to prepare small- and large-size chips on the same batch of recipient wax blocks at the same time; if only different batch numbers can be used, the pre-test slice and dot matrix can be retained. After the latter batch arrives, 5-10 overlapping samples are selected for IHC. Compare the signal strength and distribution trend, and adjust the score cutoff when the difference is large.