I had to create a fd=new FormData() object and use the [.append()][1] method before sending it through axios to my Django API, otherwise I receive a 400 error.
In my backend the profile image is related through a OneToOne relationship to the user model. Therefore it is serialized as a nested object and expects this for the put request to work.
All changes to the state within the frontend are done with the this.setState method. I believe important part is the handleSubmit method at the end.
First my axios put request:
export const PutUser=(data)=>(dispatch,getState)=>{                                                                                                                                                                                                                                                                                                                                                                                                                                           
    dispatch({type: AUTH_USER_LOADING});                                                                                                                                                                                                 
    const token=getState().auth.token;                                                                                                                                                                                                                       
    axios(                                                                                                                                                                                                                                                   
    {                                                                                                                                                                                                                                                        
    ¦ method:'put',                                                                                                                                                                                                                                          
    ¦ url:`https://<xyz>/api/account/user/`,                                                                                                                                                                                           
    ¦ data:data,                                                                                                                                                                                                                                             
    ¦ headers:{                                                                                                                                                                                                                                              
    ¦ ¦ Authorization: 'Token '+token||null,                                                                                                                                                                                                                 
    ¦ ¦ 'Content-Type': 'multipart/form-data',                                                                                                                                                                                                               
    ¦ }                                                                                                                                                                                                                                                      
    })                                                                                                                                                                                                                                                       
    ¦ .then(response=>{                                                                                                                                                                                                                                      
    ¦ ¦ dispatch({                                                                                                                                                                                                                                           
    ¦ ¦ ¦ type: AUTH_USER_PUT,                                                                                                                                                                                                                               
    ¦ ¦ ¦ payload: response.data,                                                                                                                                                                                                                            
    ¦ ¦ });                                                                                                                                                                                                                                                  
    ¦ })                                                                                                                                                                                                                                                     
    ¦ .catch(err=>{                                                                                                                                                                                                                                          
    ¦ ¦ dispatch({                                                                                                                                                                                                                                           
    ¦ ¦ ¦ type:AUTH_USER_PUT_ERROR,                                                                                                                                                                                                                          
    ¦ ¦ ¦ payload: err,                                                                                                                                                                                                                                      
    ¦ ¦ });                                                                                                                                                                                                                                                  
    ¦ })                                                                                                                                                                                                                                                     
  }      
My handleSubmit method needs to create the following json object, where the image attribute gets replaced by the actual user input:
user:{
username:'charly',
first_name:'charly',
last_name:'brown',
profile:{
image: 'imgurl',
  }
}
Here is my handleSumit method inside the component:
check append
handleSubmit=(e)=>{                                                                                                                                                                                                                                      
¦ e.preventDefault();                                                                                                                                                                                                                                                                                                                                                                                                                  
¦ let fd=new FormData();                                                                                                                                                                                                                                 
¦ fd.append('username',this.state.username);                                                                                                                                                                                                             
¦ fd.append('first_name',this.state.first_name);                                                                                                                                                                                                         
¦ fd.append('last_name',this.state.last_name);                                                                                                                                                                                                                                                                                                                                                                                                                  
¦ if(this.state.image!=null){fd.append('profile.image',this.state.image, this.state.image.name)};                                                                                                                                                                                                                                                                                                                                                        
¦ this.props.PutUser(fd);                                                                                                                                                                                                                                
};