Journal selection is not simply a search for the highest impact factor. A well-matched journal reaches readers who care about the specific question your study answers. An ambitious target may be reasonable, but prestige alone says little about whether the editors consider the work appropriate for their audience.
Start with scope and readership. Does the journal publish the kind of immunology question you investigate? Does it accept your article type? Look at recent papers—not just the journal's broad description—to see how closely their questions, evidence and level of mechanistic detail resemble your manuscript.
Next consider practical requirements: word and figure limits, data policies, publishing model, article-processing charges and submission documents. Check these against the journal's current official instructions. A journal can be an excellent scientific fit yet an impractical choice because of cost, format or an essential policy requirement.
A useful shortlist includes several journals and one honest reason for each choice. Record the fit with your central finding, the intended readership and the largest possible obstacle. You can then discuss the trade-offs with co-authors before spending time adapting the manuscript.
No adviser can promise that a journal will accept or review a paper. What good selection support can do is make the decision transparent, based on the published evidence and journal requirements rather than wishful thinking.