To my knowledge, a xenograft will only be accepted into a mouse with compromised immune system or if implanted into an part of the mouse shielded from immune responses - such as for subcapsular kidney implantation.

Immune deficient mouse lines each have certain immune components. For example, athymic nude mice still have some immune cell components relatively intact, including NK cells, macrophages, B cells, granulocytes, and dendridic cells.

Immune deficient NOD/SCID mice can be manipulated to have their immune system partially 'humanized' by irradiation of pups followed by implantation of human blood or bone marrow cells - not all immune cell populations are restored - in particular certain T cell populations will be absent.

Xenografts are important for determining the tumor responses to therapy, and are especially useful in orthotopic models. However, to understand the immune biology of a tumor type, syngenic tumor models are still very important. There are many excellent syngenic tumor models for various tumor types, including some that have disease progression patterns similar to that seen in human patients. It is important to carefuly match the tumor background to the background of the host mouse, remembering that mouse populations show genetic drift over time. This drift causes divergence between tumor cell lines and the mouse line it was derived from as well as between mouse populations from different breeding colonies. This genetic change over time can be a source of unexpected immune responses to tumors assumed to be syngenic- so watch out for unexpected regressions in controls. More than 5% spontaneous regression in the controls should be a warning that something unexpected is happening.

Geneticaly engineered mice can also be used to provide a platform for studying cancers arising from certain known mutations, and can be useful in development of immune strategies for altering the course of disease progression.

TC-1 tumors in immunocompetent Balb/c mice work great because they recruit CD4+ Tregs, tumor associated macrophages and other negative regulatory cells intratumorally from about day 6 post implant on. This makes the system well suited for studying treatments with immunomodulatory effects. The T cell restricted antigens expressed by the tumors are well published.

The system noted above is not a xenograft, but may suit your purpose depending on what that is, perhaps as a screen.

To my knowledge, a xenograft will only be accepted into a mouse with compromised immune system or if implanted into an part of the mouse shielded from immune responses - such as for subcapsular kidney implantation.

Immune deficient mouse lines each have certain immune components. For example, athymic nude mice still have some immune cell components relatively intact, including NK cells, macrophages, B cells, granulocytes, and dendridic cells.

Immune deficient NOD/SCID mice can be manipulated to have their immune system partially 'humanized' by irradiation of pups followed by implantation of human blood or bone marrow cells - not all immune cell populations are restored - in particular certain T cell populations will be absent.

Xenografts are important for determining the tumor responses to therapy, and are especially useful in orthotopic models. However, to understand the immune biology of a tumor type, syngenic tumor models are still very important. There are many excellent syngenic tumor models for various tumor types, including some that have disease progression patterns similar to that seen in human patients. It is important to carefuly match the tumor background to the background of the host mouse, remembering that mouse populations show genetic drift over time. This drift causes divergence between tumor cell lines and the mouse line it was derived from as well as between mouse populations from different breeding colonies. This genetic change over time can be a source of unexpected immune responses to tumors assumed to be syngenic- so watch out for unexpected regressions in controls. More than 5% spontaneous regression in the controls should be a warning that something unexpected is happening.

Geneticaly engineered mice can also be used to provide a platform for studying cancers arising from certain known mutations, and can be useful in development of immune strategies for altering the course of disease progression.

A xenograft is, by definition, transplantation of cells or tissue across species. For the tumor not to be rejected by the host immune system as foreign, the host must be immunocompromised. Therefore studying cancer-specific immune response using xenografts really isn't informative. Also, xenografts in immunocompromised animals rarely metastasize, which further restricts their urility. I think we spend far too much effort studying primary tumor models and not nearly enough studying metastasis. It is metastasis that kills most cancer patients, and therapies that shrink primary tumors (which in real life usually are surgically excised) often are ineffective against metastatic tumors.

To learn about the immune response to cancer it is necessary to use an immunocompetent host, which means using syngeneic mouse tumors in a mouse host. Karen Rockwell above has excellent comments about drift and spontaneous regression in controls.

Another approach is to use genetically engineered mouse (GEM) models. Richmond and Su (2008, PMC2562196) published an excellent critique of the GEM approach, pointing out some pitfalls that are not normally considered.

The problem with models is they often simplify the complexity of human cancers out of existence. This complexity is an essential feature of the disease, and designing models that eliminate that then end up as I term them, "playing games with models." In this I include engineering the model to be susceptible to the therapy.

I use NOD/SCID mice to study a xenograft cancer model for DFTD. In order to study immune system responses I must partially reconstitute their immune system with splenocytes from Balb/C mice. Do not use splenocytes from C57/BL6 as these will result in GVH rejection

Generally if you're trying to examine the interactions between a tumor and the immune system it is preferable to have a syngeneic host (i.e a humanized mouse for a xenograft with human cells). Currently there are several routes to at least partially inducing a human immune system in mice, and these can be used for the evaluation of certain immune-based treatments (see http://altogenlabs.com/xenograft-models/lung-cancer-xenograft/ll2-xenograft-model/).